Protein Crystals: Water remediation project

Transcription

1 Protein Crystals: Water remediation project Important decisions for the Protein Crystals: Water remediation project decided to move away from Pd2+ due to the lack of environmental interest I am currently analyzing more toxic compounds like Cd2+, Ni2+, Pb2+, As3+,and As5+ Proposed figures what the figures should theoretically look like Mass production of micro-protein crystals produce crystals with µm yields are 0.5 1g /50 ml some problems with protein crystal stability long term <1 week these high yield conditions are at lower protein solubility conditions so I am going to try and cross-link under lower solubility conditions I have found some base conditions that work okay and have about 7 g of ~3 µm crystals to work with Metal loading protocol Got trained on the ICP-AE Trying to develop correct protocol First round of result showed good results with Cd2+ and Ni2+ I saw decent adsorption 2.6 g Cd / kg crystal and 16.8 g Ni / kg crystal Second round of screening Cd2+, Ni2+, Pb2+, As3+,and As5+ was not so fruitful. I did not see any adsorption I did not stir these samples (not enough room in the vortexer) I have ordered a new shaker that has a capacity of 32 test tubes

2 Purposed figures for paper -numbering is to denote the order of data gathering Kinetics 1 st 3 rd Concentration adsorbate Metal loading kinetics As3+ Pb2+ Cd2+ Ni2+ Concentration of NiCl 4 2- in solution Size Difference Time Time 4 th (optional) Width Width Concentration of NiCl 4 2- in solution Aspect Ratio Diffusivity Difference Time a c b c b a (101) (110) These two figures should combine to illustrate that: Because the major pores in lysozyme run parallel with the c-axis the aspect ratio should play a large role in the adsorption kinetics. a c b Length Equilibrium 2 nd Adsorption Isotherm µg adsorbate / kg adsorbent Ni2+ Cd2+ Pb2+ As3+ Initial conc. µg/l adsorbate in solution

3 Mass production of micro-protein crystals I have been able to produce crystals with sizes from µm and yields from 0.5 1g /50 ml Protein crystal stability long term <1 week I think that the problem is that these high yield conditions are at lower protein solubility conditions. I am going to try and cross-link under lower solubility conditions. 7 g of 3 µm of stock crystals <1 aspect ratios so they should give quicker equilibrium times

4 Virus Crystals: 2D array of gold nanoparticles Important decisions for the Virus Crystals: 2D array of gold nanoparticles I would like to move away from the drug delivery project and change to trying to produce 2D array of gold nanoparticles. Project plan schematic of how to produce a 2D array of gold nanoparticles AFM studies It should be possible to image the outer face of a virus crystal and see the individual virons with AFM It should also be possible to image the 2D array of gold nanoparticles on the surface Crystal indexing Because the orientation of the crystal in relation to the substrate will determine the pattern that will form it is critical to correlate the crystal faces to their corresponding miller indices Dr. Lin should be able to provide us with this information

5 Important decisions for the Virus Crystals: 2D array of gold nanoparticles I do not have the time to develop the drug delivery project. I believe that I have the skills or can develop them relatively quickly for the 2D array project The 2D array project would fit better into my thesis The drug delivery project would require more virus than 2D array project Growing the larger porous hexagonal crystals is even more trickier than the BCC Literature Hexagonal Ours: growth time 3-6 months These are the micro batches from the summer Not hexagonal We have had some relative success in growing BCC crystal Uncross-linked BCC Cross-linked

6 Project Plan 2-D array of gold nanoparticles using CPMV crystals as a "mask CPMV Gold substrate Crystals grown on gold surface PEG-SH mono-thiol Dissolve crystal Thiolated exposed surface PEG-SH di-thiol nm Gold substrate Gold nanoparticle PEG-SH di-thiol PEG-SH thiol Gold nanoparticles rotation

7 AFM studies My first AFM images AFM images: dry CPMV on a Mica substrate CPMV This was a test of the difficulties in AFM and if I could see the virus relatively easy. The nice looking spheres in this image were nm wide. I am thinking that since these virons are 30 nm we might have enough horizontal resolution to get close enough to the actual size It should be possible to get an AFM image of the crystal outer face which should be approximately a representation of what is in contact with the surface We should certainly be able to detect if there is a 2D gold array on the surface after processing Cucumber Mosaic Virus ~38 nm Malkin, A. J.; Thorne, R. E., Methods 2004, 34, (3),

8 Crystal indexing Gold substrate Crystals grown on gold surface Because the orientation of the crystal in relation to the substrate will determine the pattern that will form it is critical to correlate the crystal faces to their corresponding miller indices Is this a crystal that has 12 sides and each side is the same rhombus shape What planes are these? I was thinking that all the faces are the {210}. I think that the only way to get 12 equal sides with a BCC crystal would be if h, k, and l are all different and {210} would be the logical choice. Is this correct? Dr. Lin should be able to provide us with this information.