1 Int. J. Electrochem. Sci., 9 (2014) International Journal of ELECTROCHEMICAL SCIENCE Beads Based Electrochemical Assay for Detection of Hemagglutinin Labeled by Two Different Types of Cadmium Quantum Dots Ludmila Krejcova 1, David Hynek 1,2, Roman Guran 1,2, Petr Michalek 1,2, Amitava Moulick 1,2, Pavel Kopel 1,2, Katerina Tmejova 1,2, Nguien Viet Hoai 1,2, Vojtech Adam 1,2, Jaromir Hubalek 1,2, Jindrich Kynicky 3, Rene Kizek 1,2* 1 Department of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University in Brno, Zemedelska 1, CZ Brno, Czech Republic, European Union 2 Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, CZ Brno, Czech Republic, European Union 3 Karel Englis College, Sujanovo nam. 356/1, CZ , Brno, Czech Republic, European Union * Received: 18 January 2014 / Accepted: 17 March 2014 / Published: 14 April 2014 In this study it is described beads based isolation assay terminated by electrochemical analysis of hemagglutinin (HA) using two different cadmium quantum dots (QDs) labelled as CdS and CdTe. The two steps assay was suggested as the first step was the automatic isolation of HA labelled by Cd QDs using glycan modified paramagnetic particles (MPs), and the second one was the electrochemical detection of HA-QDs complex by voltammetry, particularly, adsorptive transfer technique coupled with differential pulse voltammetry Brdicka reaction was used for detection of HA and differential pulse anodic stripping voltammetry was used for detection of Cd. Both methods were optimized. Suggested assay can be used for the subtyping and quantification of HA. Keywords: Voltammetry; Paramagnetic Particles; Influenza Hemagglutinin; Influenza Vaccine; Quantum Dots; 1. INTRODUCTION One of the great treat of humanity across the history is pandemic occurrence. 21 st century, which is marked by increasing globalization, airplane transport together with population growth, multiplies this risk . Influenza belongs to the most dangerous due to high rateof mutation of surface s influenza antigens as hemagglutinin (HA) and neuraminidase (NA) . Influenza viruses are pathogens capable of continuously evading immune response. Accumulation of mutations in the
2 Int. J. Electrochem. Sci., Vol. 9, antigenic sites is called the antigenic drift [3,4]. In circulating influenza viruses this antigenic drift is a major process, which accumulates mutations of the antibody binding sites of receptor proteins and enables the virus to evade recognition by hosts antibodies, which often translates into periodic epidemics of influenza [3,5]. HA and NA play opposite roles in interaction of virus with host cell receptor . HA initiates the infection and binds sialic acid receptor. NA eliminates sialic acid from host cell receptor, which HA bound and allows the release of new replicated virions . There have been identified 9 subtypes of NA (1-9) and 16 subtypes of HA (1-16). All known subtypes (HxNy) are found in birds, but many subtypes are endemic in humans, cats, dogs, horses, ferrets and wheals [8-10]. There are several experts that believe that only influenza A viruses of the A/H1, A/H2, and A/H3 subtypes can cause pandemics, as no other virus subtypes are known to cause pandemics in the past . There were three great pandemic in the last century. The first one Spanish flu (H1N1, 1918), which was considered as the biggest one with 50 million victims , and it was followed by two others, but moderate pandemics: Asian Flu (H2N2, 1957) and Hong-Kong flu (H3N2, 1968) . However, based on historical records, most influenza experts agree with one thing that there will likely be future pandemics, of unknown severity [14,15]. The influenza A virus that will most probably cause the next influenza pandemic is a highly debated topic in virology . To the influenza spread, a flexible vaccination WHO s program, based on periodic production of novel versions of vaccine, is adapted to the actually prevalent stain(s) . HA is considered to be the main target for antibodies upon vaccination or native infection and is the key component of the vaccine. Quantitative and qualitative analysis of HA is crucial-point before the vaccine is placed to the market. Therefore, suitable tools for this purpose are still searched for. Separation of magnetic-bead-labelled biomolecules (or cells) from a liquid solution is well documented and widely practiced application today and is extremely important in process engineering . Paramagnetic particles (MPs) are considered as the unique isolation tool with broad spectrum of features (easy handling by the magnet, well modified surfaces and large surface to small size) [18,19]. In this study we used streptavidin modified MPs for binding biotinylated glycan due to streptavidinbiotin affinity. This step was followed by linkage of Cd QDs labelled vaccine hemagglutinin to glycan modified MPs. End point of isolation was electrochemical analysis of both HA-QDs complexes. Two different techniques of differential pulse voltammetry (DPV) were used. 2. EXPERIMENTAL PART 2.1. Chemicals Tris(2-carboxyethyl)phosphine (TCEP) was from Molecular Probes (Oregon, USA). Co(NH 3 ) 6 Cl 3 and other chemicals were purchased in ACS purity from Sigma Aldrich (Sigma-Aldrich, USA) unless indicated otherwise. Stock solutions were prepared with ACS water. ph value was measured using inolab Level 3 (Wissenschaftlich-Technische Werkstatten GmbH; Weilheim, Germany). Deionised water underwent demineralization by reverse osmosis using Aqua Osmotic 02 (Aqua Osmotic, Tisnov, Czech Republic) and was subsequently purified using Millipore RG (MiliQ
3 Int. J. Electrochem. Sci., Vol. 9, water, 18 MΏ, Millipore Corp., USA). Deionised water was used for rinsing, washing and preparation of buffers Hemagglutinin As the standards of HA of Influenza A and B types, influenza vaccine Vaxigrip (Sanofi Pasteur, France), which contains inactivated and split virions of the following strands: A/California/7/2009 (H1N1)-derived strain used NYMC X-179A, A/Perth/16/2009 (H3N2)-like strain used NYMC X-187 derived from A/Victoria/210/2009 and B/Brisbane/60/2008, was used. Strains were propagated in fertilised hens eggs from healthy chicken flocks. Vaxigrip contains 15 micrograms of all of three HA per 0.5 ml Quantum dots Preparation of CdS quantum dots CdS quantum dots (QDs) were prepared using a slightly modified version of the published method . Cadmium nitrate tetrahydrate Cd(NO 3 ) 2 4H 2 O (0.1 mm) was dissolved in ACS water (25 ml). 3-mercaptopropionic acid (35 µl, 0.4 mm) was slowly added to the stirred solution. Afterwards, the ph was adjusted to 9.11 with 1 M NH 3 (1.5 ml). Sodium sulphide monohydrate Na 2 S 9H 2 O (0.1 mm) in ACS water was poured into the solution while vigorously stirring. The acquired yellow solution was stirred for 1 h. Prepared CdS-quantum dots were stored in the dark at 4 ºC Preparation of CdTe quantum dots CdTe QDs were prepared according to slightly modified method published by Duan et al. . Briefly, cadmium acetate dihydrate Cd(OAc) 2 2H 2 O ( g) was dissolved in ACS water (44 ml) and 100 mg of trisodium citrate dihydrate was added with stirring. Solution of g Na 2 TeO 3 in 1.25 ml of water was poured into the first solution followed by 3-mercaptopropionic acid (100 µl, 1.14 mm). Afterwards, solid NaBH 4 (50 mg) was added with vigorous stirring and hydrogen evolution was observed, followed by colour change of solution to slightly yellow. After 30 min of stirring, 2 ml of solution was heated in glass vial in Multiwave 3000 Microwave Reaction System (Anton Paar, Graz, Austria) using rotor 64MG5. Reaction conditions were as it follows: power 300 W, 120 ºC and time 18 min. Obtained CdTe QDs were stored in dark at 4 ºC Labelling of HA from Vaxigrip by QDs Vaxigrip (500 µl containing of 45 µg HA) was reduced and washed with water (5 x 400 µl) on an Amicon 3k centrifugal filter device (Millipore, Massachusetts, USA) and mixed with a solution of prepared QDs (500 µl). This mixture was shaken for 24 h at room temperature (Biosan Orbital
4 Int. J. Electrochem. Sci., Vol. 9, Shaker OS-10, Biosan Ltd. Riga, Latvia). The volume of solution was reduced to 100 µl on an Amicon Ultra 3k, diluted with water and washed 5 times using centrifuge 5417R (Eppendorf, Hamburg, Germany). The washed sample was diluted to 1 ml with ACS water and used for measurements Characterization of vaxi HA, CdTe and CdS, HA-CdS and HA-CdTe complex by electrochemical analysis Characterization of hemagglutinin by AdT DPV Characterization of HA and its complex with quantum dots by adsorptive transfer technique coupled with differential pulse voltammetry (AdT DPV) were performed with a 663 VA Stand instrument (Metrohm, Herisau, Switzerland), which was equipped with a standard cell consisting of three electrodes, a cooled sample holder and a measurement cell set at 4 C (Julabo F25, JulaboDE, Seelbach, Germany). The three-electrode system was consisted of a hanging mercury drop electrode (HMDE) with a drop area of 0.4 mm 2 as the working electrode, an Ag/AgCl/3M KCl reference electrode and a platinum electrode acting as the auxiliary. Software GPES 4.9 was used for data analysis. The analysed samples were deoxygenated prior to measurement by purging with argon ( %) saturated with water for 120 s. Brdicka supporting electrolyte containing 1 mm Co(NH 3 ) 6 Cl 3 and 1M ammonia buffer (NH 3 (aq) + NH 4 Cl, ph = 9.6) was used. The supporting electrolyte was exchanged after each analysis. The parameters of the measurement were as follows: initial potential of -0.7 V; end potential of V; modulation time s; time interval 0.2 s; step potential V; modulation amplitude 0.025V sample volume: 5 µl. Time of accumulation was optimized Detection of cadmium by DPASV Cd in QDs itself and Cd from HA-QDs complexes were detected by differential pulse anodic stripping voltammetry (DPASV). All of measurements were performed using a 663 VA Stand (Metrohm), equipped with a standard cell with three electrodes. The three electrode system was consists of a hanging mercury drop electrode (HMDE) with a drop area of 0.4 mm 2 as the working electrode, an Ag/AgCl/3M KCl reference electrode and a glassy carbon acting as the auxiliary electrode. GPES 4.9 software was employed for data processing. The analysed samples were deoxygenated prior to measurements by purging with argon (99.999%). Acetate buffer (0.2 M CH 3 COONa + CH 3 COOH, ph 5) was used as a supporting electrolyte. The supporting electrolyte was replaced after each analysis. The parameters of the measurement were as follows: purging time 100 s; deposition potential V; equilibration time 2 s; modulation time s; interval time 0.2 s; initial potential V; end potential -0.4 V; step potential V; modulation amplitude V; sample volume: 5 µl; volume of measurement cell: 1000 μl (5 μl of sample; 995 μl acetate buffer). Time of accumulation was optimized.
5 Int. J. Electrochem. Sci., Vol. 9, Characterization of vaxi HA, HA-CdS and HA-CdTe complex by gel electrophoresis Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) was performed using Mini Protean Tetra apparatus with gel dimension of cm (Bio-Rad, USA). First 12.5% (m/v) running, then 5% (m/v) stacking gel was poured. The gel was prepared from 30% (m/v) acrylamide stock solution with 1 % (m/v) bisacrylamide. The polymerization of the running or stacking gels was performed at room temperature for 30 min. Prior to analysis the samples were mixed with reducing sample buffer in a 2:1 ratio. The samples were incubated at 93 C for 3 min, and then the sample was loaded onto a gel. For determination of the molecular mass, the protein ladder Precision plus protein standards from Biorad was used. The electrophoresis was run at 150 V for 1 h at laboratory temperature (23 C) (Power Basic, Biorad USA) in tris-glycine buffer (0.025 M Trizmabase, 0.19 M glycine and 3.5 mm SDS, ph = 8.3). Then the gels were stained Coomassie-blue. The procedure of rapid Coomassie-blue staining was adopted from Wong et al.  Robotic pippeting station Computer controlled automated pipetting station, ep-motion 5075 (Eppendorf, Germany) was used for automated sample handling prior to electrochemical analysis. Transfer was ensured by a robotic arm with pipetting adaptors (TS50, TS300) and a gripper for platform transport (TG-T), placed on A1 position. Tips were placed in positions A3 (eptips 300) and A2 (eptips 50). At position A4 Thermomixer was located. At position B1, module reservoir for washing solutions and waste were placed. Position C1 was thermostated (Epthermoadapter PCR96). A thermorack for 24 x ml microtubes (Position B3) was used to store working solutions. For sample preparation 96-well PCR plate with a maximal well volume of 200 μl was used. After separation, the magnetic particles were forced apart using a Promega magnetic pad (Promega, USA). The program sequence was edited and the station was controlled in peditor 4.0 (Eppendorf) Isolation of HA-QDs complexes by glycan modified paramagnetic particles Streptavidin Dynabeads M-270 were purchased from Life Technologies (Carlsbad, California, USA). Biotinylated multivalent-glycan ( [Neu5Acα2-3Galβ1-3GlcNAcβ1-PAA-biotin]) was supplied from GlycoTech (Gaithersburg, MD, USA). Vaxigrip (HA) was purchased from Sanofi Pasteur (France). As the standard of HA, recombinant HA from H3N2 Influenza-A Virus Brisbane 10/07 (Prospecbio, Israel) was used. The first step of isolation was the pipetting of 10 μl of streptavidin Dynabeads M-270 to microplates PCR 96 (Eppendorf, Germany), and then the plate was transferred to a magnet. Stored solution was aspirated from the MPs and MPs were washed three times with 100 μl of phosphate buffer (0.3 M, ph 7.4, made from NaH 2 PO 4 and Na 2 HPO 4 ). Thereafter 20 μl of biotinylated glycan were added to each of the wells and incubated (30 min, 25 C, 400 rpm). After incubation, the sample was washed three times with phosphate buffer (0.3 M, ph 7.4). Subsequently 20 μl of HA-QDs was added. Mixture in each well was further incubated (400 rpm) and washed threetimes with 100 μl of phosphate buffer (0.3 M, ph 7.4). In the last step, 35 μl of phosphate buffer (0.3
6 Int. J. Electrochem. Sci., Vol. 9, M, ph 7.4) was added followed by the treatment of ultrasound needle (2 min). The plate was transferred to the magnet and the supernatant was analysed using AdT DPV Brdicka raction and DPASV. The effects of time and temperature of glycan HA-QDs complex interaction on the yield of product of isolation were investigated. The detected substances were identified as cadmium (QDs) and influenza antigen (HA from Vaxigrip) Electrochemical analysis of the isolated sample Two different methods of DPV were used for electrochemical detection of isolated complex. For HA determination optimized AdT DPV Brdicka reaction was used. Determination of metal part of HA-QDs complexes were performed by the optimized DPASV in the presence of acetate buffer. All of measurements were performed with a 663 VA Stand instrument (Metrohm, Switzerland) Descriptive statistics Data were processed using MICROSOFT EXCELs (USA) and STATISTICA.CZ Version 8.0 (Czech Republic). The results are expressed as mean ± SD unless noted otherwise. The detection limits (3 signal/noise, S/N) were calculated according to Long and Winefordner , whereas N was expressed as a standard deviation of noise determined in the signal domain unless stated otherwise. 3. RESULTS AND DISCUSSION Recent reports showed that influenza can spread and undergo mutational changes more and more rapidly [24,25] and due to this fact causes illness among humans, or animal-human transmitted zoonosis. Highly pathogenic avian influenza (HPAI) is contagious viral disease affecting poultry with socio-economic impact. It is listed as a notifiable disease by the World Organisation for Animal Health (OIE) and represents a zoonotic threat . The zoonotic outbreak of H7N9 subtype of HPAI that occurred in eastern China in the spring of 2013 resulted in 135 confirmed human cases, of which 44 were lethal . Due to this fact early detection of this virus is highly needed . The detection of the influenza virus is based on a wide range of techniques. Sauter and co-workers described X-ray crystal structures for several complexes between influenza virus hemagglutinin and derivatives of its cell-surface receptor, sialic acid (Neu5Ac) . Gao and co-workers developed a panel with lysates of seasonal influenza virus (H1N1, H3N2 and B), serials of diluted H5N1 virus lysates, and in vitro transcribed H5 hemagglutinin (HA) and an artificial gene RNAs for real-time polymerase chain reaction (RT-PCR) and rrt-pcr quality control assessment . However, these techniques required quite sophisticated equipment. In comparison, the electrochemical detection offers simple, attractive and easy-to-miniaturise alternative [30,31]. Here, we suggested a biosensor, which consists of HA- QDs complex isolation and subsequent electrochemical detection of target molecules [32-37]. In this
7 Int. J. Electrochem. Sci., Vol. 9, case, method for isolation and detection of HA labelled by two different QDs (CdS and CdTe) was designed and implemented Characterization of vaxi HA, CdTe and CdS, HA-CdS and HA-CdTe complex by electrochemical analysis For indirect detection of HA and its signal amplification quantum dots was used as a marker. Two different QDs (CdTe and CdS) were applied and their effect on the isolation process was suggested. Quantum dots (QDs) own many unique optic properties such as high quantum yield, broad absorption spectra, narrow emission spectra, low bleaching and excellent photostability, and for this reason they are widely applied in biomedical imaging. Firstly, both of QDs and its complexes with HA from Vaxigrip were prepared by processes, which were described in Experimental section. Then individual substances: HA (Vaxigrip ) and Cd (CdTe and CdS) and the same substances in complexes (HA-CdTe and HA-CdS) were characterized by voltammetry Characterization of hemagglutinin by AdT DPV For characterization of HA itself and HA in complexes with QDs, AdT DPV Brdicka reaction electrolyte was used. The main principle of AdT technique is based on an accumulation of target molecules onto the electrode surface from low volume and transfer of an electrode with adsorbed target molecules to the pure supporting electrolyte, where no interferences is present . AdT DPV Brdicka reaction was utilized for detection of HA-QDs complex previously [39,40]. The reaction mechanism is based on the catalytic evolution of hydrogen on mercury electrode from protein containing SH groups in Brdicka solution. Typical voltammograms of HA and HA in complexes were compared in the Figs. 1A and 1B. Four peaks (X, Y, RS2Co, and Cat2 ) were detected and characterized in the obtained voltammograms. We were interested in two peaks that appeared only in HA-QDs complexes: peak X and peak Y. Peak Y was observed in both of complexes (HA-CdS and HA-CdTe) in same position (-1.09 ± 0.02 V). The difference was determined in position of peak X. In HA-CdS voltammogram peak X was detected at potential ± 0.02 V. In HA-CdTe complex peak X was found at slightly negative potential (-1.05 ± 0.02 V). Our next interest was focused on peak Cat2 corresponding to the presence of SH moieties, and interaction of HA with QDs by SH moieties in HA structure. During the interaction between HA and QDs, free -SH groups in HA are probably saturated by QDs and this effect causes occurrence of the peaks X and Y as a proof of metal reduction in HA-QDs complexes . For this reason Cat2 peak of HA voltammogram was higher compared to HA-QDs complexes.
8 Int. J. Electrochem. Sci., Vol. 9, Figure 1. Comparison of typical DP voltammograms of HA in HA-QDs complex (solid line) and vaxi HA itself (dashed line) measured by AdT DPV Brdicka reaction for (A) HA-CdS and (B) HA- CdTe. For all measurements AdT DPV was used with parameters as follows: purge time 30 s, initial potential -0.7 V; end potential -1.8 V; accumulation time 120 s; potential step; V; amplitude V. Comparison of typical DP voltammograms of Cd in HA-QDs complex (solid line) and QDs itself (dashed line) measured by DPASV for (C) HA-CdS and (D) HA- CdTe. For Cd peak determination DPASV was used with parameters as follows: initial potential -0.8 V; end potential -0.5 V; deposition potential -0.8 V; equilibration time 5 s; modulation time 0.06 s; time interval 0.2 s; potential step V; modulation amplitude V. (E) Characterization of vaxi HA, HA standard (H3N2), HA-CdTe and HA-CdS complexes, CdTe and CdS quantum dots by SDS-PAGE. Reducing conditions and 10% gel were used Detection of cadmium by DPASV The interaction of QDs with HA was also monitored electrochemically by DPASV in acetate buffer. Our interest was put on Cd peak. Its height and position were detected and differences between Cd peaks (in QDs and HA-QDs) were also described. Differences in position and peak height were described in Figs. 1C and 1D. Cd peak in both QDs is higher and peak potential is more positive compared to Cd peak in HA-QDs complexes. Cd peak position of both QDs is placed at potential ± V, Cd peak of HA-CdS at potential ± V and Cd peak of HA-CdTe at potential ± V.
9 Int. J. Electrochem. Sci., Vol. 9, Characterization of vaxi HA, HA-CdS and HA-CdTe complex by gel electrophoresis SDS-PAGE was used for characterization of HA (Vaxigrip and H3N2 standard), QDs (CdTe and CdS) and its complexes (HA-CdTe and HA-CdS) as it is shown in Fig. 1E. After Coomassie-blue staining of a gel, there are three bands of the different size corresponding to entire HA, HA1 and HA2 subunits in standard of H3N2. The entire HA (HA 0) protein is band with a molecular weight of 75 kda, two others bands (approx. 50 kda and 25kDa) corresponded to HA1and HA2 subunits. Compared to Vaxigrip HA itself and in complexes with CdTe and CdS QDs, the intensity of bands is lower and position of bands is little shifted. Shift is somewhat larger when we compared H3N2 standard with complexes than comparison with HA Vaxigrip itself. In lines of pure QDs there are no bands corresponded to HA Time of accumulation and calibration curves After that we characterized that we successfully formed HA-QDs complex, we tested the effect of time of accumulation on HA and Cd peak heights of the formed complexes. The influence of time of accumulation on Cd peak in HA-CdS and HA-CdTe complexes is shown in Fig. 2A. In spite of the fact that the peak height was increasing in the whole tested interval, we selected 400 s as the compromise between sensitivity and the time of the analysis. Further, we tested the same parameter for HA detection b AdT DPV Brdcika reaction. Based on the results showed in Fig. 2B it follows that time of accumulation of 120 s was the optimal. Under the optimized parameters, we measured for Cd and HA and both types of QDs calibration curves, which are shown in Figs. 2C and 2D, respectively. All measured dependences were linear within tested concentration interval Optimization of HA-QDs complexes isolation and electrochemical analysis of isolated samples Other authors described HA-glycan interaction as a basic specific connection for influenza virus isolation [43,44]. Comparison of binding of HA to the host cells and construction of biosensors is shown in Fig. 3A. Inspiration of natural targeting of influenza virus is obvious. Isolation of both of HA-QDs complexes were provided by the protocol, described in section 2.8 and according scheme presented in Fig. 3B. Streptavidin modified MPs were used as the platform, to which biotinylated glycan was bounded (Fig. 3B part a). Paramagnetic beads applications require setting particle properties (magnetic behaviour of the beads must be associated with appropriate bead surface modifications in order to allow covalent bonding or simple unspecific adsorption of biomolecules (proteins, antibodies, nucleic acids). Usually, the magnetic beads are tailor made for a specific final application . In the next step there was HA-CdTe and/or HA-CdS complex bounded on the glycan conjugated MPs based on glycan-ha affinity (Fig. 3B part b). Fully automated setup was developed using an automatic pipetting robot as was described in section 2.7. The isolation products were analysed using electrochemical methods (Fig. 3B part c).
10 Int. J. Electrochem. Sci., Vol. 9, Figure 2. Dependence of relative peak height (related to the maximal value) on time of accumulation for (A) Cd peak and (B) HA peak. Dependence of relative peak height (related to the maximal value) on concentration of (C) cadmium and (D) concentration of HA. Red colour was used for HA (HA peak, measured by AdT DPV Brdicka reaction), blue colour was used for Cd (Cd peak, measured by DPASV). Unfilled points (HA-CdS complex), filled points (HA-CdTe complex). The influence of time and temperature on the interaction between glycan and HA-QDs complex and on the yield of the isolated HA labelled by QDs was investigated. We tested six different values of temperatures (5, 25, 35, 45, 55, and 65 C). Changes in Cd and HA peak heights showed increasing dependency related on the increasing temperature, but only to 45 C. Temperature of 45 C was established as the best according to the Cd peak height (Fig. 4A) and HA peak height (Fig. 4B). Further, seven different times of reaction (5, 10, 15, 20, 30, 45 and 60 minutes) and its effect on Cd and HA peaks heights were investigated. The highest effect of reaction time was observed for Cd peak (Fig. 4C) after 20 minutes interaction for both quantum dots. Then the highest effect of reaction time was observed for HA peak (Fig. 4D). As the optimum 30 minutes (HA-CdS) was established, and for isolation of HA-CdTe time of interaction of 20 minutes was selected. If we summarize the results of the optimization, the best conditions were as follows: the reaction temperature 45 C and the reaction time minutes.
11 Int. J. Electrochem. Sci., Vol. 9, Figure 3. (A) Comparison of natural binding of influenza virus to glycan receptor located on the host cell and relation to our isolation procedure. (B) Scheme of fully automated isolation procedure connected with electrochemical detection of HA-QDs complexes. (a) Biotinylated glycan binding to streptavidin modified paramagnetic particles (MPs), (b) HA-QDs complex binding to glycan conjugated MPs, isolation of HA-CdS and/or HA-CdTe followed by ultrasound breaking of MPs-HA-QDs complexes, (c) electrochemical detection of HA and Cd peaks for both HA-QDs complexes by voltammetry. HA peak was measured by differential pulse voltammetry Brdicka reaction coupled with adsorptive transfer technique (AdT DPV) and Cd peak was measured by differential pulse anodic stripping voltammetry (DPASV).
12 Int. J. Electrochem. Sci., Vol. 9, Figure 4. Effect of (A) and (B) temperature, and (C) and (D) reaction time on interaction between HA- QDs complex and MPs modified by glycan. The efficiency was observed by using electrochemical analysis of Cd peak for (A) temperature and (C) reaction time. All measurements of Cd peak were provided by DPASV. The second determined parameter was HA peak height and its affecting by (B) temperature (D) and reaction time. For all measurements of HA peak AdT DPV Brdicka reaction was used. Red colour was used for hemagglutinin, blue colour was used for cadmium. Light shade of individual colour was related to the HA-CdS complex, dark shade of individual colour was related to the HA-CdTe complex. 4. CONCLUSIONS In this study we described method for rapid isolation of influenza HA, which was connected with electrochemical detection of HA labelled with various quantum dots (CdS and CdTe). The whole system was extended by automation of whole isolation protocol. An advantage of this assay is the
13 Int. J. Electrochem. Sci., Vol. 9, ability to provide dual electrochemical detection of products of the isolation as HA or metal part of the complex. The electrochemical detection of metal part of HA-QDs complexes could be more sensitive and suggested method can be considered as a suitable tool for determination of the specific influenza antigen. This method is not applicable only for the antigen of influenza virus but it can be extended for detection of specific proteins of other pathogens or cancer markers [45-50]. ACKNOWLEDGEMENTS Financial support from NanoBioMetalNet CZ.1.07/2.4.00/ is highly acknowledged. The authors wish to express their thanks to Michal Zurek for perfect technical assistance. CONFLICT OF INTEREST: The authors have declared no conflict of interest. References 1. C.-M. Liao and S.-H. You, Stoch. Environ. Res. Risk Assess., 28 (2014) T. N. Athmaram, S. Saraswat, B. Sikarwar, S. K. Verma, A. K. Singh and M. Boopathi, J. Med. Virol., 86 (2014) J. P. Radomski, P. Plonski and W. Zagorski-Ostoja, Mol. Phylogenet. Evol., 70 (2014) I.-B. Lian, H.-D. I. Wu, W.-T. Chang and D.-Y. Chao, Plos One, 9 (2014) L. Stone, R. Olinky and A. Huppert, Nature, 446 (2007) Q. J. Chen, S. P. Huang, J. J. Chen, S. Q. Zhang and Z. Chen, PLoS One, 8 (2013) Y. Abed, A. Pizzorno, X. Bouhy, C. Rheaume and G. Boivin, J. Virol., 88 (2014) K. Ohishi, Aquabiology, 28 (2006) T. W. Vahlenkamp and T. C. Harder, Berliner Munchener Tierarztl. Wochenschr., 119 (2006) J. C. Jones, T. Baranovich, B. M. Marathe, A. F. Danner, J. P. Seiler, J. Franks, E. A. Govorkova, S. Krauss and R. G. Webster, J. Virol., 88 (2014) M. Imai, S. Herfst, E. M. Sorrell, E. J. A. Schrauwen, M. Linster, M. De Graaf, R. A. M. Fouchier and Y. Kawaoka, Virus Res., 178 (2013) A. Gagnon, M. S. Miller, S. A. Hallman, R. Bourbeau, D. A. Herring, D. J. D. Earn and J. Madrenas, PLoS One, 8 (2013) E. Tognotti, Emerg. Infect. Dis., 19 (2013) D. Kobasa, A. Takada, K. Shinya, M. Hatta, P. Halfmann, S. Theriault, H. Suzuki, H. Nishimura, K. Mitamura, N. Sugaya, T. Usui, T. Murata, Y. Maeda, S. Watanabe, M. Suresh, T. Suzuki, Y. Suzuki, H. Feldmann and Y. Kawaoka, Nature, 431 (2004) N. Komadina, J. McVernon, R. Hall and K. Leder, Emerg. Infect. Dis., 20 (2014) B. Brandenburg, W. Koudstaal, J. Goudsmit, V. Klaren, C. Tang, M. V. Bujny, H. Korse, T. Kwaks, J. J. Otterstrom, J. Juraszek, A. M. van Oijen, R. Vogels and R. H. E. Friesen, PLoS One, 8 (2013) M. A. M. Gijs, Microfluid. Nanofluid., 1 (2004) F. Gieseler, H. Gamperl, F. Theophil, I. Stenzel, T. Quecke, H. Ungefroren and H. Lehnert, Cell Biol. Int., 38 (2014) L. P. Li, L. N. Xu, Z. Li, Y. Bai and H. W. Liu, Anal. Bioanal. Chem., 406 (2014) H. Li, W. Y. Shih and W. H. Shih, Ind. Eng. Chem. Res., 46 (2007) 2013.
14 Int. J. Electrochem. Sci., Vol. 9, J. L. Duan, L. X. Song and J. H. Zhan, Nano Res., 2 (2009) C. Wong, S. Sridhara, J. C. A. Bardwell and U. Jakob, Biotechniques, 28 (2000) G. L. Long and J. D. Winefordner, Anal. Chem., 55 (1983) A S. Van Borm, M. Jonges, B. Lambrecht, G. Koch, P. Houdart and T. van den Berg, Transbound. Emerg. Dis., 61 (2014) B. Bett, J. Henning, P. Abdu, I. Okike, J. Poole, J. Young, T. F. Randolph and B. D. Perry, Transbound. Emerg. Dis., 61 (2014) J. D. Gabbard, D. Dlugolenski, D. Van Riel, N. Marshall, S. E. Galloway, E. W. Howerth, P. J. Campbell, C. Jones, S. Johnson, L. Byrd-Leotis, D. A. Steinhauer, T. Kuiken, S. M. Tompkins, R. Tripp, A. C. Lowen and J. Steel, J. Virol., 88 (2014) I. Grabowska, K. Malecka, A. Stachyra, A. Gora-Sochacka, A. Sirko, W. Zagorski-Ostoja, H. Radecka and J. Radecki, Anal. Chem., 85 (2013) N. K. Sauter, G. D. Glick, R. L. Crowther, S. J. Park, M. B. Eisen, J. J. Skehel, J. R. Knowles and D. C. Wiley, Proc. Natl. Acad. Sci. U. S. A., 89 (1992) R. B. Gao, Y. Gao, L. Y. Wen, M. Shao, S. M. Zou, C. G. Li, L. Yang, X. Y. Li, W. Wang and Y. L. Shu, BMC Infect. Dis., 11 (2011) M. Pedrero, S. Campuzano and J. M. Pingarron, Sensors, 9 (2009) L. Krejcova, D. Hynek, V. Adam, J. Hubalek and R. Kizek, Int. J. Electrochem. Sci., 7 (2012) D. Fialova, L. Krejcova, L. Janu, I. Blazkova, O. Krystofova, D. Hynek, P. Kopel, J. Drbohlavova, M. Konecna, M. Vaculovicova, J. Kynicky, J. Hubalek, P. Babula, R. Kizek and V. Adam, Int. J. Electrochem. Sci., 8 (2013) L. Krejcova, D. Huska, D. Hynek, P. Kopel, V. Adam, J. Hubalek, L. Trnkova and R. Kizek, Int. J. Electrochem. Sci., 8 (2013) L. Krejcova, D. Hynek, P. Kopel, M. A. R. Merlos, K. Tmejova, L. Trnkova, V. Adam, J. Hubalek and R. Kizek, Int. J. Electrochem. Sci., 8 (2013) L. Krejcova, L. Nejdl, D. Hynek, S. Krizkova, P. Kopel, V. Adam and R. Kizek, Molecules, 18 (2013) L. Krejcova, L. Nejdl, M. A. Merlos Rodrigo, M. Zurek, M. Matousek, D. Hynek, O. Zitka, P. Kopel, V. Adam and R. Kizek, Biosens. Bioelectron., 54 (2014) P. Sobrova, M. Vaculovicova, J. Hubalek, V. Adam and R. Kizek, Int. J. Mol. Sci., 14 (2013) P. Sobrova, M. Ryvolova, V. Pekarik, J. Hubalek, V. Adam and R. Kizek, Int. J. Electrochem. Sci., 8 (2013) V. Adam, J. Baloun, I. Fabrik, L. Trnkova and R. Kizek, Sensors, 8 (2008) J. Petrlova, D. Potesil, R. Mikelova, O. Blastik, V. Adam, L. Trnkova, F. Jelen, R. Prusa, J. Kukacka and R. Kizek, Electrochim. Acta, 51 (2006) P. Sobrova, L. Vyslouzilova, O. Stepankova, M. Ryvolova, J. Anyz, L. Trnkova, V. Adam, J. Hubalek and R. Kizek, PLoS ONE, 7 (2012) K. Tmejova, D. Hynek, P. Kopel, S. Krizkova, I. Blazkova, L. Trnkova, V. Adam and R. Kizek, Colloid Surf. B-Biointerfaces in press (2014). 43. E. Suenaga, H. Mizuno and K. K. R. Penmetcha, Biosens. Bioelectron., 32 (2012) K. Hatano, K. Matsuoka and D. Terunuma, Chem. Soc. Rev., 42 (2013) J. Drbohlavova, V. Adam, R. Kizek and J. Hubalek, Int. J. Mol. Sci., 10 (2009) M. Ryvolova, J. Chomoucka, L. Janu, J. Drbohlavova, V. Adam, J. Hubalek and R. Kizek, Electrophoresis, 32 (2011) M. Ryvolova, K. Smerkova, J. Chomoucka, J. Hubalek, V. Adam and R. Kizek, Electrophoresis, 34 (2013) S. Skalickova, O. Zitka, L. Nejdl, S. Krizkova, J. Sochor, L. Janu, M. Ryvolova, D. Hynek, J. Zidkova, V. Zidek, V. Adam and R. Kizek, Chromatographia, 76 (2013) 345.
15 Int. J. Electrochem. Sci., Vol. 9, P. Sobrova, I. Blazkova, J. Chomoucka, J. Drbohlavova, M. Vaculovicova, P. Kopel, J. Hubalek, R. Kizek and V. Adam, Prion, 7 (2013) M. Stanisavljevic, L. Janu, K. Smerkova, S. Krizkova, N. Pizurova, M. Ryvolova, V. Adam, J. Hubalek and R. Kizek, Chromatographia, 76 (2013) The Authors. Published by ESG (www.electrochemsci.org). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution license (http://creativecommons.org/licenses/by/4.0/).
Int. J. Electrochem. Sci., 8 (2013) 10805-10817 International Journal of ELECTROCHEMICAL SCIENCE www.electrochemsci.org Flow Injection Electrochemical Analysis of Complexes of Influenza Proteins with CdS,
Optimal Conditions for F(ab ) 2 Antibody Fragment Production from Mouse IgG2a Ryan S. Stowers, 1 Jacqueline A. Callihan, 2 James D. Bryers 2 1 Department of Bioengineering, Clemson University, Clemson,
STANDARD OPERATING PROCEDURE Title: Evaluation using Western Blot SOP#: M-103 Version #: 1 Author: R. Saul Date Approved: Feb. 5, 2009 Date Modified: 1. PURPOSE The purpose of this document is to describe
Electronic Supplementary Material (ESI) for Journal of Materials Chemistry A. This journal is The Royal Society of Chemistry 2014 Supporting Information Available Facile synthesis of corallite-like Pt-Pd
Revision No.: ZJ0002 Issue Date: Aug 7 th, 2008 HBV Quantitative Real Time PCR Kit Cat. No.: HD-0002-01 For Use with LightCycler 1.0/LightCycler2.0/LightCycler480 (Roche) Real Time PCR Systems (Pls ignore
Western Blot SOP Protein transfer from SDS-PAGE to nitrocellulose membrane using the Trans-Blot SD cell (Western). Date: 8/16/05, 10/31/05, 2/6/06 Author: N.Oganesyan, R. Kim Edited by: R. Kim Summary:
Western Blot Analysis with Cell Samples Grown in Channel-µ-Slides Polyacrylamide gel electrophoresis (PAGE) and subsequent analyses are common tools in biochemistry and molecular biology. This Application
Amersham High Molecular Weight Calibration Kit for native electrophoresis A lyophilized mixture of five highly purified well-characterized proteins for use in molecular weight estimation under non-denaturing
GE Healthcare Amersham Low Molecular Weight Calibration Kit for SDS Electrophoresis A lyophilized mixture of six highly purified well-characterized proteins for use in molecular weight determination in
EZ-Run Protein Gel Solution EZ-Run Protein Standards EZ-Run Gel Staining Solution Traditional SDS-Page Reagents Protein Electrophoresis protein electrophoresis Introduction Sodium dodecyl sulfate polyacrylamide
ProteoSilver Plus Silver Stain Kit Product Code PROT-SIL2 Store at Room Temperature TECHNICAL BULLETIN Product Description The ProteoSilver Plus Silver Stain Kit is an exceptionally sensitive, MALDI-MS
Western Blotting All steps are carried out at room temperature unless otherwise indicated. Recipes for all solutions highlighted bold are included at the end of the protocol. SDS-PAGE 1. Construct an SDS-PAGE
WHO Prequalification of Diagnostics Programme PUBLIC REPORT Product: Genscreen ULTRA HIV Ag-Ab Number: PQDx 0096-031-00 Abstract Genscreen ULTRA HIV Ag-Ab with product codes 72386 and 72388, manufactured
292PR 01 G-Biosciences 1-800-628-7730 1-314-991-6034 firstname.lastname@example.org A Geno Technology, Inc. (USA) brand name Classic Immunoprecipitation Utilizes Protein A/G Agarose for Antibody Binding (Cat.
HIS-Select Nickel Affinity Gel Catalog Number P6611 Storage Temperature 2 8 C TECHNICAL BULLETIN Product Description HIS-Select Nickel Affinity Gel is an immobilized metalion affinity chromatography (IMAC)
Viruses Chapter 10: Viruses Lecture Exam #3 Wednesday, November 22 nd (This lecture WILL be on Exam #3) Dr. Amy Rogers Office Hours: MW 9-10 AM Too small to see with a light microscope Visible with electron
Western Blotting: Mini-gels Materials a Protein Extraction Buffer (for callus or kernel), Solution Stock Final Volume Tris-HCl ph 80 1 M 200 mm 20 ml NaCl 4 M 100 mm 25 ml Sucrose 2 M 400 mm 20 ml EDTA
Electronic Supplementary Material (ESI) for ChemComm. This journal is The Royal Society of Chemistry 2016 Supporting Information for Ultrasensitive detection of microbial cells by magnetic focus enhanced
TRI Reagent For processing tissues, cells cultured in monolayer or cell pellets Catalog Number T9424 Store at room temperature. TECHNICAL BULLETIN Product Description TRI Reagent is a quick and convenient
Product Manual QuickTiter FeLV Core Antigen ELISA Kit (FeLV p27) Catalog Numbers VPK-155 96 wells FOR RESEARCH USE ONLY Not for use in diagnostic procedures Introduction Feline leukemia virus (FeLV) is
SDS-PAGE Protocol Mutated from the SDS-PAGE protocol written by the Lord of the Flies Pouring the resolving gel 1. Clean glass plates with soap and water, then with ethanol. Assemble the glass plates and
RealStar HBV PCR Kit 1.0 11/2012 RealStar HBV PCR Kit 1.0 For research use only! (RUO) Product No.: 201003 96 rxns INS-201000-GB-02 Store at -25 C... -15 C November 2012 altona Diagnostics GmbH Mörkenstraße
Product Manual QuickTiter Hepatitis B Surface Antigen (HBsAg) ELISA Kit Catalog Numbers VPK-5004 VPK-5004-5 96 assays 5 x 96 assays FOR RESEARCH USE ONLY Not for use in diagnostic procedures Introduction
HiPer Ion Exchange Chromatography Teaching Kit Product Code: HTC001 Number of experiments that can be performed: 5 Duration of Experiment: Protocol: 5-6 hours Storage Instructions: The kit is stable for
Protein Detection Methods & Western Blots 1.Sodium DodecylSlufate(SDS)-PolyacrylamideGel Electrophoresis (SDS-PAGE) Visualize many proteins at once 2. SDS-PAGE combined with immunoblotting (Western) Visualize
Protocol for Western Blotting Materials Materials used on Day 3 Protease inhibitor stock: 1 μg/μl pepstatin A in DMSO 200 μm leupeptin in OG Buffer 200 mm PMSF: Freshly made. Ex) 34.8 mg PMSF in 1 ml isopropanol
To make Glycerol Stocks of Plasmids ** To be done in the hood and use RNase/DNase free tips** 1. In a 10 ml sterile tube add 3 ml autoclaved LB broth and 1.5 ul antibiotic (@ 100 ug/ul) or 3 ul antibiotic
Electronic Supplementary Material (ESI) for RSC Advances. This journal is The Royal Society of Chemistry 2015 Supporting Information Rational design of Au nanorods assemblies for highly sensitive and selective
The public health risk of influenza in pigs recent insights, key knowledge gaps Prof. Kristien Van Reeth Laboratory of Virology, Faculty of Veterinary Medicine, Ghent University, Belgium H1N1, H3N2 and
Topic J10+11: Molecular-biological methods + Clinical virology I (hepatitis A, B & C, HIV) To study: PCR, ELISA, your own notes from serology reactions Task J10/1: DNA isolation of the etiological agent
#3. Acid - Base Titrations 27 EXPERIMENT 3. ACID-BASE TITRATIONS: DETERMINATION OF CARBONATE BY TITRATION WITH HYDROCHLORIC ACID BACKGROUND Carbonate Equilibria In this experiment a solution of hydrochloric
User Protocol 539551 Rev. 16-September-04 JSW Page 1 of Protein Kinase Assay Kit, Universal Cat. No. 539551 Introduction Protein kinases catalyze the transfer of gamma phosphate from adenosine triphosphate
Electrophoresis and Electroblotting of Proteins The purpose of the next lab exercises will be to study the relative amounts of β-actin in cells of the B-16 melanoma, liver and muscle of mice. Electrophoresis
DEVELOPMENT OF A QUARTZ CRYSTAL MICROBALANCE (QCM) IMMUNOSENSOR TO DETECT POTENTIALLY ALLERGENIC SESAME IN FOOD Fatima Tazeen Husain, Margit Cichna-Markl, Romana Schirhagl and Franz Ludwig Dickert Department
SDS-PAGE and western blot for low molecular weight proteins (2-20kDa) Merav Marom Shamur, Smart Assays Aim: Analysis of low molecular weight proteins by SDS-PAGE and western blot under reducing conditions.
2D gel Protocol 1. Lysis and Protein Extraction from cells Prepare cell lysates with Trizol extraction by following Kathleen Lyons s protocol: AfCS Procedure Protocol PP00000155, Version 1, 05/12/03 (Ref.1).
PROTOCOL Western Blotting Transfer and Detection Procedure 1850 Millrace Drive, Suite 3A Eugene, Oregon 97403 02-11 DESCRIPTION Western Blotting Transfer and Detection Procedure ADDITIONAL MATERIALS REQUIRED
METHOD USED TO EXTRACT TOTAL MUSCLE PROTEIN FOR WESTERN BLOT USING TRIS-EDTA BUFFER* SOLUTIONS FOR SAMPLE EXTRACTION 1. Tris-EDTA Buffer, ph 8.3 1 liter 50 mm Tris 6.06 g 10 mm EDTA 3.72 g Adjust ph to
Avian influenza From Wikipedia, the free encyclopedia This article may require cleanup to meet Wikipedia's quality standards. Please improve this article if you can. (October 2008) Avian influenza, sometimes
Human serum albumin (HSA) nanoparticles stabilized with intermolecular disulfide bonds Wentan Wang, Yanbin Huang*, Shufang Zhao, Ting Shao and Yi Cheng* Department of Chemical Engineering, Tsinghua University,
1 Lab 2 Biochemistry Learning Objectives The lab has the following learning objectives. Investigate the role of double bonding in fatty acids, through models. Developing a calibration curve for a Benedict
Cat. No. CS-330 Amount 1 Kit For in vitro use only. Quality guaranteed for 3 months. Store at 4 C. Application Screen for thermal stability of proteins as a function of the FUNDAMENTAL variables ph and
Electronic Supplementary Material (ESI) for RSC Advances. This journal is The Royal Society of Chemistry 2016 Supporting Information Nanosilver Rainbow: A rapid and facile method to tune different colors
BIOTECHNOLOGY Levels: 11-12 Units of Credit: 1.0 CIP Code: 51.1201 Prerequisite: Biology or Chemistry Skill Certificates: #708 COURSE DESCRIPTION is an exploratory course designed to create an awareness
17 th INTERNATIONAL BIOLOGY OLYMPIAD 9-16 JULY 2006 Río Cuarto República Argentina PRACTICAL TEST 3 Biochemistry Student code: 17 th INTERNATIONAL BIOLOGY OLYMPIAD 9-16 JULY 2006 Río Cuarto República Argentina
Protein Precipitation Protocols Notes: All reagents need to high purity/hplc quality. All tubes used should be new or hand cleaned thoroughly with Micro90 detergent. High quality water needs to be used
Chem 405 Biochemistry Lab I Experiment 2 Quantitation of an unknown protein solution. Introduction: The determination of protein concentration is frequently required in biochemical work. Several methods
Running protein gels and detection of proteins 1. Protein concentration determination using the BIO RAD reagent This assay uses a colour change reaction to give a direct measurement of protein concentration.
FluoroTag FITC Conjugation Kit Product Number FITC1 Storage Temperature 2 8 C TECHNICAL BULLETIN Product Description The FluoroTag FITC Conjugation Kit is suitable for the conjugation of polyclonal and
Instructions for use PCR KIT FOR EXTRACTION OF RNA AND REAL TIME PCR DETECTION KIT FOR HEPATITIS C VIRUS RNA Research Use Only Qualitative Uni Format VBD0798 48 tests valid from: December 2013 Rev11122013
Introduction To Real Time Quantitative PCR (qpcr) SABiosciences, A QIAGEN Company www.sabiosciences.com The Seminar Topics The advantages of qpcr versus conventional PCR Work flow & applications Factors
1 Information The rapid evolution of influenza viruses The influenza-a virus Influenza virus type A (Fig. 1) can occur in different variants. Its genetic information is segmented and consists of 8 separate
KAMIYA BIOMEDICAL COMPANY Mouse C-Peptide I EIA For the quantitative determination of C-Peptide I in mouse plasma, serum and urine. Cat. No. KT-367 For Research Use Only. 1 Rev. 091207 PRODUCT INFORMATION
Protocol for GenomePlex Whole Genome Amplification from Formalin-Fixed Parrafin-Embedded (FFPE) tissue Application Guide... 2 I. Description... 2 II. Product Components... 2 III. Materials to be Supplied
Method for Western Blotting Western Blotting ELECTROPHORESIS Prepare and run an SDS PAGE gel. Select a gel percent which will give the best resolution for the size of antigen being analyzed (if known).
ELISA BIO 110 Lab 1 Immunity and Disease Introduction The principal role of the mammalian immune response is to contain infectious disease agents. This response is mediated by several cellular and molecular
Canine creatine kinase MB isoenzyme (CK-MB)ELISA Kit Catalog No. CSB-E15852c (96T) This immunoassay kit allows for the in vitro quantitative determination of canine CK-MB concentrations in serum and plasma.
Introduction to Agarose Gel Electrophoresis: A Precursor to Cornell Institute for Biology Teacher s lab Author: Jennifer Weiser and Laura Austen Date Created: 2010 Subject: Molecular Biology and Genetics
ab185915 Protein Sumoylation Assay Ultra Kit Instructions for Use For the measuring in vivo protein sumoylation in various samples This product is for research use only and is not intended for diagnostic
Authored by S. Steve Zhou, Ph.D. Microbac Laboratories, Inc., Microbiotest Division The purpose of Viral Clearance evaluation is to assess the capability of a manufacturing production process to inactivate
竞 争 性 分 析 Epitope Mapping 实 验 方 法 ABSTRACT The simplest way to determine whether two monoclonal antibodies bind to distinct sites on a protein antigen is to carry out a competition assay. The assay can
A Reference Measurement System for C-reactive Protein David M. Bunk, Ph.D. Chemical Science and Technology Laboratory National Institute of Standards and Technology Definition of the Measurand: Human C-reactive
In vitro analysis of pri-mirna processing by Drosha-DGCR8 complex (Narry Kim s lab) 1-1. Preparation of radiolabeled pri-mirna transcript The RNA substrate for a cropping reaction can be prepared by in
Essentials of Real Time PCR About Real-Time PCR Assays Real-time Polymerase Chain Reaction (PCR) is the ability to monitor the progress of the PCR as it occurs (i.e., in real time). Data is therefore collected
RayBio Human Fibronectin ELISA Kit Catalog #: ELH-FN1 User Manual Last revised April 15, 2016 Caution: Extraordinarily useful information enclosed ISO 13485 Certified 3607 Parkway Lane, Suite 100 Norcross,
6 Characterization of Casein and Bovine Serum Albumin (BSA) Objectives: A) To separate a mixture of casein and bovine serum albumin B) to characterize these proteins based on their solubilities as a function
Peptide Antibody Production A) Peptide BioSynthesis (http://www.biosyn.com, 800-227-0627) B) Conjugation of peptide to KLH (Imject Maleimide Activated KLH, PIERCE=Thermo #77605, 10 mg) C) Peptide affinity
DNA Separation Methods Chapter 12 DNA molecules After PCR reaction produces many copies of DNA molecules Need a way to separate the DNA molecules from similar sized molecules Only way to genotype samples
HUMAN AGR2 ELISA KIT P a g e 1 HUMAN ANTERIOR GRADIENT 2 (AGR2) ELISA KIT FOR THE QUANTITATIVE DETERMINATION OF HUMAN AGR2 CONCENTRATIONS IN CELL CULTURES, SERUM AND PLASMA. PURCHASE INFORMATION: ELISA
Protein immunoblotting (Western blotting) Dr. Serageldeen A. A. Sultan Lecturer of virology Dept. of Microbiology SVU, Qena, Egypt email@example.com Western blotting -It is an analytical technique used to
Lab 5: DNA Fingerprinting You are about to perform a procedure known as DNA fingerprinting. The data obtained may allow you to determine if the samples of DNA that you will be provided with are from the
is a is a state of the art transfection reagent, specifically designed for the transfer of sirna and mirna into a variety of eukaryotic cell types. is a state of the art transfection reagent, specifically
GS Junior Titanium Series May 2010 (Rev. April 2011) For life science research only. Not for use in diagnostic procedures. 1. WORKFLOW The emulsion-based clonal amplification (empcr amplification) of a
1 RAGE Rotating Field Gel Electrophoresis (RAGE) is a variation on Pulsed Field Gel Electrophoresis (PFGE) and gives similar results. We use equipment that was only briefly marketed by Stratagene, at far
Conductivity measurement on pure water according to the recommendations of the USP Pharmacopoeia USP24-NF19 By Patricia DALMAS, Product Specialist, Radiometer Analytical Pharmaceutical laboratories working
Experiment 2 Purification by Recrystallization Objectives 1) To be able to select an appropriate recrystallizing solvent. 2) To separate and purify acetanilide by recrystallization. 3) To compare the melting
Western Blotting Sive Lab Protocol March 2007 Prepare samples: For zebrafish embryos: Option 1: Take live embryos and put into 1.5 ml tube with E3. Centrifuge gently for 1-2 minutes -yolk lipids will rise
Balancing Act Teacher Information Objectives In this activity, students neutralize a base with an acid. Students determine the point of neutralization of an acid mixed with a base while they: Recognize
Laboratory Procedures Serological detection of avian influenza A(H7N9) virus infections by turkey haemagglutinationinhibition assay 23 May 2013 The WHO Collaborating Center for Reference and Research on
EXPERIMENT 10: Electrical Conductivity Chem 111 INTRODUCTION A. Electrical Conductivity A substance can conduct an electrical current if it is made of positively and negatively charged particles that are