United States Pharmacopeia Methods Selected Methods for High-Performance Liquid Chromatography Presented by Vydac / The Separations Group, Inc. 17434 Mojave Street Hesperia, CA 92345 USA Telephone: 760-244-6107 Toll-free : 1-800-247-0924 Facsimile: USA 760-244-1984
The United States Pharmacopeia The first United States Pharmacopoeial Convention met in 1820 and the Convention met thereafter every ten years until 1970, when the schedule was increased to every five years. A Compendium of assays and test procedures is now published every five years with supplements as needed during the five year period. The current Compendium is US Pharmacopeia 23 / National Formulary 18, adopted in 1995. The mission statement of the US Pharmacopeia. The United States Pharmacopeia promotes the public health by establishing and disseminating officially recognized standards of quality and authoritative information for the use of medicine and related articles by health care professionals, patients and consumers. Many USP methods use high-performance liquid chromatography (HPLC) as an assay method. The USP allows latitude in the choice of the HPLC column used to perform approved methods by defining the column as to the packing material which it contains. USP 23 - NF 18 defines 33 column packings used in the methods described in the compendium (USP 23 / NF 18, Pages 2024-2025). Vydac offers HPLC columns that are suitable for a large portion of the methods using HPLC which are listed in the USP 23 - NF 18 including: Type Description Vydac Columns L1 Octadecyl silane chemically bonded to porous silica or 201HS, 3, 5 and 10 µm ceramic microparticles, 3 to 10 µm in diameter. 218TP, 5 and 10 µm L7 Octyl silane chemically bonded to totally porous silica 208HS, 3, 5 and 10 µm microparticles, 5 to 10 µm in diameter. 208TP, 5 and 10 µm L11 Phenyl groups chemically bonded to porous silica 219TP, 5 and 10 µm particles, 5 to 10 µm in diameter. L26 Butyl silane chemically bonded to totally porous silica 214TP, 5 and 10 µm particles, 5 to 10 µm in diameter. The methods shown in this booklet represent only a small fraction of those using HPLC and for which Vydac HPLC columns can be used. Please contact Vydac for additional information regarding the use of Vydac HPLC columns for USP method assays. Table of Contents Page 1 Page 2 Page 3 Page 4 Page 5 Page 6 Page 7 Page 8 Page 9 Page 10 Back Cover The U.S. Pharmacopeia Description of HPLC packings Vydac HPLC columns Acetaminophen, aspirin and caffeine capsules Acyclovir Ampicillin Naproxen tablets Penicillin V Sulfisoxazole Acetyl Pharmacopeia methods specifying Vydac HPLC columns Vydac HPLC columns for U.S. Pharmacopeia methods Descriptions Ordering information Page 1
Vydac is one of a few manufacturers of high quality synthetic HPLC-grade silica. Manufactured in two porosities - 90 Å HS silica and 300 Å TP silica - high purity synthetic silica particles bonded using the best available bonding chemistries constitute the latest in HPLC column technologies. Vydac HS reverse-phase columns are only the latest in a long line of HPLC column developments over the past twenty-five years of which Vydac has been a part. Vydac HS columns show negligible peak asymmetry when chromatographing basic compounds (Figure 1) and represent a clear advance over columns developed even a few years ago. These columns not only meet the requirements for UPS L1 (201HS) and L7 (208HS) packings but also offer opportunities for performance improvements by using small particle (3µ) versions of the traditional 5µ analytical columns. This permits much higher sample throughput without compromising quantitation or resolution. High resolution separations of a wide variety of pharmaceutical compounds are routine (Figure 2). Pharmaceutical Analysis Vydac HPLC Columns Vydac 300 Å pore reverse-phase packings (TP products) are respected in the bioseparations and biotechnology fields as the premier columns for the reverse-phase analysis and purification of proteins and peptides. Vydac TP columns are not only specified for several USP methods for polypeptide analysis, they have shown superior results for compounds that are difficult to analyze using small pore packings (see Penicillin V, Page 6). Vydac offers TP columns that meet USP definitions of L1 (218TP), L7 (208TP), L11 (219TP) and L26 (214TP) packings. Figure 1. Analysis of basic compounds Column: 201HS54 (C 18, 5µ small pore, 4.6 x 250 mm) Eluent: 30:70 water:acn Flow rate: 1.0 ml/min Sample: methyl paraben ethyl paraben N,N-dimethylaniline 10 min Figure 2. Rapid analysis of pharmaceuticals Column: 208HS3410 (C 8, 3µ small pore, 4.6 x 250 mm) Eluent: 15-60% ACN in water over 10 minutes Flow rate: 1.5 ml/min Sample: 1. barbital 2. phenacemide 3. ethotoin 4. phenobarbital 5. phensuximide 6. mephenytoin 7. carbamazepine 8. methsuximide 9. diazepam 1 2 3 4 5 6 7 8 9 10 min Page 2
US Pharmacopeia XXIII Acetaminophen, aspirin and caffeine capsules Acetaminophen, aspirin and caffeine capsules: Analgesic Method: "The liquid chromatograph is equipped with a 275 nm detector and a 4.6 mm x 10 cm column that contains 5 µm packing L1, (L1 packings are defined as "octadecyl silane chemically bonded to porous silica or ceramic microparticles, 3 to 10 µm in diameter") and is maintained at 45 (+/-) 1 degrees. The flow rate is about 2 ml per minute. Chromatograph the standard preparation, and record the responses as directed under procedure: the tailing factor for each analyte peak is not more than 1.2, the resolution, R, between any of the analyte and internal standard peaks is not less than 1.4... " (USP XXII-NF XVII, Page 16) Summary: The US Pharmacopeia method involves dissolving a portion of several acetaminophen / aspirin / caffeine capsules in methanol/acetic acid and analysis by HPLC. Analysis of the Standard preparation (figure at right) shows that the Vydac 201HS5415 column met the criteria for the HPLC columns to be used in this method, except for the length of 15 cm. Analyte tailing factors were below the method maximum of 1.2 for all three analyte peaks: acetaminophen - 1.19; caffeine - 1.15; aspirin - 1.12. Resolution between the four peaks - three analyte peaks and the benzoic acid internal standard - were all greater than the method minimum of 1.4: acetaminophen/caffeine - 4.3; caffeine/aspirin - 10.2; aspirin/benzoic acid - 3.6. Conclusion: Vydac 201HS5415 columns meet the criteria for the HPLC columns to be used in this method and offer high resolution analysis and quantitation of acetaminophen, aspirin and caffeine. Column: 201HS5415 (C 18, 5 micron small pore,.46 x 15 cm) Eluent: water:methanol:glacial acetic acid (69:28:3) Flow rate: 2.0 ml/min Sample: acetaminophen, aspirin, caffeine (100 µg/ml) and benzoic acid (600 µg/ml) Injection: 10 microliters Detection: UV absorbance at 275 nm Temperature: 45 degrees C. acetaminophen HO NHCOCH 3 caffeine O N O N N N aspirin COOH OCO benzoic acid 0 1 2 3 4 5 min Performance Improvements... For in-process, formulations and other applications. State-of-the-art three micron L1 HPLC columns, such as the Vydac 201HS3410, offer improved performance and reduced analysis time compared to the five micron columns commonly used. Vydac 201HS3410 columns reduce analysis time from seven to less than four minutes and exceed the method resolution and analyte peak tailing requirements. Column: 201HS3410 (C 18, 3 micron small pore,.46 x 10 cm) Eluent: water:methanol:glacial acetic acid (69:28:3) Flow rate: 2.0 ml/min Sample: acetaminophen, aspirin, caffeine (100 µg/ml) and benzoic acid (600 µg/ml) Injection: 10 microliters Detection: UV absorbance at 275 nm Temperature: 45 degrees C. acetaminophen caffeine aspirin benzoic acid 0 1 2 3 4 min Page 3
US Pharmacopeia XXIII Acyclovir Acyclovir: Antiviral Method: "The liquid chromatograph is equipped with a 254 nm detector and a 4.2 mm x 30 cm column that contains packing L1 (L1 packings are defined as "octadecyl silane chemically bonded to porous silica or ceramic micro-particles, 3 to 10 µm in diameter"). The flow rate is about 3 ml per minute. Chromatograph the Standard preparation, and record the peak responses as directed under procedure: The resolution, R, between the acyclovir and guanine peaks is not less than 2.0, the tailing factor for the analyte peak is not more than 2... " (USP XXII-NF XVII, Supplement 6, Page 2790) Summary: The US Pharmacopeia method for the analysis of acyclovir involves the dissolution of acyclovir in sodium hydroxide and subsequent HPLC analysis. In analysis of the Resolution standard (figure at right), the Vydac 201HS54 column met the criteria for the HPLC columns to be used in this method, with slightly different dimensions, with a resolution of 10.5. This exceeds the resolution of 2.0 specified in the method. Acyclovir had a tailing factor of 1.25, less than the 2.0 maximum specified in the method. Conclusion: Vydac 201HS54 columns offer high resolution analysis and quantitation of acyclovir. Column: 201HS54 (C 18, 5 micron small pore,.46 x 25 cm) Eluent: water:glacial acetic acid (99.9:0.1) Flow rate: 3.0 ml/min Sample: acyclovir (100 µg/ml) and guanine (14.2 µg/ml) Injection: 10 microliters guanine acyclovir O N HN N H2N N CH2OCH2CH2OH 0 1 2 3 4 5 6 7 8 9 min Performance Improvements... For in-process, formulations and other applications. State-of-the-art three micron L1 HPLC columns, such as the Vydac 201HS3405, offer improved performance and reduced analysis time compared to the five micron column used above. The 201HS3405 column, with retention characteristics similar to the 201HS54 column, gives real time analysis under USP conditions - except for particle size and column length - and exceeds the method requirements with a resolution of 3.5 and a tailing factor of 1.4. Analysis time is reduced from seven minutes to about two minutes. Column: 201HS3405 (C 18, 3 micron small pore,.46 x 5 cm) Eluent: water:glacial acetic acid (99.9:0.1) Flow rate: 3.0 ml/min Sample: acyclovir (100 µg/ml) and guanine (14.2 µg/ml) Injection: 10 microliters guanine acyclovir 0 1 2 3 min Page 4
US Pharmacopeia XXIII Ampicillin Ampicillin: Antibiotic Method: "The liquid chromatograph is equipped with a 254 nm detector and a 4 mm x 5 cm pre-column containing 5-10 - µm packing L1 (L1 packings are defined as "octadecyl silane chemically bonded to porous silica or ceramic micro-particles, 3 to 10 µm in diameter"), and a 4 mm x 30 cm analytical column containing 5-10 µm packing L1. The flow rate is about 2 ml per minute. Chromatograph the resolution solution, and record the peak responses as directed under procedure: the resolution, R, between the caffeine and ampicillin peaks is not less than 2.0... " (USP XXII-NF XVII, Page 87) Summary: The US Pharmacopeia method for the analysis of ampicillin involves dissolution of ampicillin in potassium phosphate / acetic acid and subsequent HPLC analysis. In the analysis of the resolution solution (figure at right), the Vydac 201HS54 column met the criteria for HPLC columns to be used in this method, with slightly different dimensions, with a resolution of 15.3, exceeding the resolution of 2.0 specified in the method. Conclusion: Vydac 201HS54 columns offer high performance analysis and quantitation of ampicillin. Column: 201HS54 (C 18, 5 micron small pore,.46 x 25 cm) Eluent: water:acetonitrile : 1 M KH 2 PO 4 : 1 N acetic acid (909:80:10:1) Flow rate: 2.0 ml/min Sample: ampicillin (1 mg/ml) and caffeine (.12 mg/ml) Injection: 20 microliters ampicillin COOH O N H C CONH H S H NH2 caffeine 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 min Performance Alternatives... Large pore, polymerically bonded C 18 columns (Vydac 218TP54) give good resolution and peak shape for the ampicillin and caffeine Resolution standard (figure at right) and result in a rapid analysis of ampicillin. The 218TP54 column had a resolution factor of 3.5, exceeding the method resolution requirement of 2.0 while reducing analysis time from fifteen minutes to five minutes. Column: 218TP54 (C 18, 5 micron large pore,.46 x 25 cm) Eluent: water:acetonitrile:1 M KH 2 PO 4 :1 N acetic acid (909:80:10:1) Flow rate: 2.0 ml/min Sample: ampicillin (1 mg/ml) and caffeine (.12 mg/ml) Injection: 20 microliters caffeine ampicillin 0 1 2 3 4 5 min Page 5
US Pharmacopeia XXIII Naproxen tablets Naproxen tablets: Non-steroidal anti-inflammatory Method: "The liquid chromatograph is equipped with a 254 nm detector and a 4.6 mm x 15 cm column that contains 5-µm packing L1 (L1 packings are defined as "octadecyl silane chemically bonded to porous silica or ceramic micro-particles, 3 to 10 µm in diameter"). The flow rate is about 1.2 ml per minute. Chromatograph the standard preparation, and record the peak responses as directed under procedure: the column efficiency, determined from the analyte peak, is not less than 4000 theoretical plates..., the resolution between the analyte and internal standard peaks is not less than 11.5... " (USP XXII-NF XVII, Page 918) Summary: The US Pharmacopeia method for the analysis of naproxen tablets requires the dissolution of a number of tablets in water/acetonitrile and subsequent HPLC analysis. Analysis of the Standard preparation (figure at right) shows that the Vydac 218TP54 column, with a naproxen theoretical plate count of 11,500, exceeded the method requirements of 4000 theoretical plates, however it fell slightly short of the resolution requirement of 11.5 with a resolution of 11.1. Conclusion: Vydac 218TP54 columns offer high resolution analysis and quantitation of naproxen with excellent peak shape, although resolution is just slightly less than method requirements. Column: 218TP54 (C 18, 5 micron large pore,.46 x 25 cm) Eluent: water:methanol:glacial acetic acid (49:50:1) Flow rate: 1.2 ml/min Sample: naproxen (25 µg/ml) and butyrophenone (0.01 µg/ml) Injection: 20 microliters CH 3O butyrophenone naproxen CH 3 CHCOOH 0 1 2 3 4 5 6 min Performance Alternatives... Vydac 201HS5415 columns, widely used for pharmaceutical analysis, give good peak shape and efficiency for naproxen and butyrophenone (figure at right), however resolution is somewhat reduced at R = 6.6. Naproxen peak efficiency is 4250 theoretical plates. Column: 201HS5415 (C 18, 5 micron small pore,.46 x 15 cm) Eluent: water:methanol:glacial acetic acid (49:50:1) Flow rate: 1.2 ml/min Sample: naproxen (25 µg/ml) and butyrophenone (0.01 µg/ml) Injection: 20 microliters butyrophenone naproxen 0 1 2 3 4 5 min Page 6
US Pharmacopeia XXII Penicillin V Penicillin V: Antibiotic Method: "The liquid chromatograph is equipped with a 254 nm detector and a 4 mm x 30 cm column that contains packing L1 (L1 packings are defined as "octadecyl silane chemically bonded to porous silica or ceramic microparticles, 3 to 10 µm in diameter"). The flow rate is about 1 ml per minute. Chromatograph the resolution solution, and record the peak responses as directed under procedure: The relative retention times are about 0.8 for penicillin G and 1.0 for penicillin V, the column efficiency determined from the penicillin V peak is not less than 1800 theoretical plates, and the resolution, R, between the penicillin G and penicillin V peaks is not less than 3.0." (USP XXII-NF XVII, Page 1037) Summary: The US Pharmacopeia method for the analysis of penicillin V involves the dissolution of penicillin V in the mobile phase and subsequent HPLC analysis. Analysis of the Resolution solution (figure below) shows that the Vydac 218TP54 column met the criteria for the HPLC columns to be used in this method - with slightly different dimensions - with a resolution of 4.9 between penicillin G and V, exceeding the method requirement of 3.0. Penicillin V had a measured peak efficiency of 7780 theoretical plates, well above the minimum requirement of 1800 plates. Many HPLC columns produce tailing peaks with penicillin G and V, making quantitation more difficult. Vydac 218TP54 columns give sharp peaks with very high efficiency for these difficult compounds. Conclusion: Vydac 218TP54 columns offer high resolution analysis and quantitation of penicillin V. Column: 218TP54 (C 18, 5 µ large pore silica,.46 x 25 cm) Eluent: water:acetonitrile:glacial acetic acid (64.425:35:.575) Flow rate: 1.0 ml/min Sample: USP Grade penicillin G (2.5 mg/ml) and Penicillin V (2.5 mg/ml) Injection: 10 microliters penicillin G penicillin V O OCH 2CONH H COOH CH N 3 CH 3 S H 0 1 2 3 4 5 6 7 8 9 10 min Page 7
US Pharmacopeia XXII Sulfisoxazole Acetyl Erythromycin estolate and sulfisoxazole acetyl oral suspension: Antibiotic Method: "The liquid chromatograph is equipped with a 254 nm detector and a 4 mm x 30 cm column that contains packing L1 (L1 packings are defined as "octadecyl silane chemically bonded to porous silica or ceramic micro-particles, 3 to 10 µm in diameter"). The flow rate is about 1.2 ml per minute. Chromatograph replicate injections of the standard preparation, and record the peak responses as directed under procedure: the resolution factor between sulfisoxazole and benzanilide is not less than 3.0... " (USP XXII-NF XVII, Supplement 4, Page 2465) Summary: The US Pharmacopeia method for the analysis of Erythromycin estolate and sulfisoxazole acetyl oral suspension involves extraction of the suspension into chloroform and drying, followed by HPLC analysis. Analysis of the Standard preparation (figure at right) shows that the Vydac 201HS54 columns meet the criteria for the HPLC columns to be used in this method, except for slightly different dimensions, with a resolution of 11.1, exceeding the minimum resolution of 3.0 specified in the method. Conclusion: Vydac 201HS54 columns offer high resolution analysis and quantitation of sulfisoxazole acetyl. Column: 201HS54 (C 18, 5 micron small pore,.46 x 25 cm) Eluent: water:acetonitrile (60:40) Flow rate: 1.2 ml/min Sample: sulfisoxazole (1 mg/ml) and benzanilide (.33 mg/ml) Injection: 5 microliters NH2 sulfisoxazole acetyl O SO2NH N benzanilide 0 1 2 3 4 5 6 7 8 9 10 11 12 min Performance Improvements... For in-process, formulations and other applications. State-of-the-art three micron L1 HPLC columns, such as the Vydac 201HS3405, offer improved performance and reduced analysis time compared to the five micron column used above. The 201HS3405 column has retention characteristics similar to the 201HS54 column, gives real time analysis under USP conditions - with small particle size and short column length - and still exceeds the method resolution requirement with a resolution of 8.0. Analysis time is reduced from thirteen minutes to about three minutes. Column: 201HS3405 (C 18, 3 micron small pore,.46 x 5 cm) Eluent: water:acetonitrile (60:40) Flow rate: 1.2 ml/min Sample: sulfisoxazole (1 mg/ml) and benzanilide (.33 mg/ml) Injection: 5 microliters sulfisoxazole acetyl benzanilide 0 1 2 3 4 5 min Page 8
US Pharmacopeia XXIII Methods Specifying Vydac HPLC Columns The following USP methods specify a Vydac HPLC column as the primary or secondary column to be used in the method. The data comes from Chromatographic Reagents Used in USP-NF and Pharmacopoeial Forum, second edition, from the United States Pharmacopoeial Convention, Inc. Method Column Specified Type Comments Clomiphene Citrate Vydac 214ATP5 C4 L26 Made with one step end-capping procedure Clomiphene Citrate Tablets: Vydac C4 L26 Doxycycline Vydac C18 L1 Doxycycline Hyclate Vydac C18 L1 Mentions that the L1 packing should be of low acidity Conjugated Estrogens Tablets Vydac 201TP L1 Insulin Vydac 218TP54 L1 Desamido insulin and other insulin related substances Insulin Injection Vydac 218TP54 L1 Insulin Human Vydac 218TP54 L1 Insulin Human Injection Vydac 218TP54 L1 Isophane Insulin Human Suspension Vydac 218TP54 L1 Insulin Human Zinc Suspension Vydac 218TP54 L1 Meclocycline Sulfosalicaylate Vydac 201TP L1 Meclocycline Sulfosalicaylate Cream Vydac 201TP L1 Somatotropin Vydac 214TP54 C4 L26 Triamterene and Hydrochlorothiazide Vydac 201TP L1 Alternative reagent Extended Capsules Triamterene and Hydrochlorothiazide Vydac 201TP L1 Alternative reagent Prompt Capsules Page 9
Vydac HPLC Columns for U.S. Pharmacopeia Methods Column Description USP Material Type 201HS3405 90Å silica, C 18, 3 µm, 4.6 x 50 mm L1 201HS3410 90Å silica, C 18, 3 µm, 4.6 x 100 mm L1 208HS3405 90Å silica, C 8, 3 µm, 4.6 x 50 mm L7 208HS3410 90Å silica, C 8, 3 µm, 4.6 x 100 mm L7 201HS51 90Å silica, C 18, 5 µm, 1.0 x 250 mm L1 208HS51 90Å silica, C 8, 5 µm, 1.0 x 250 mm L7 201HS52 90Å silica, C 18, 5 µm, 2.1 x 250 mm L1 208HS52 90Å silica, C 8, 5 µm, 2.1 x 250 mm L7 201HS54 90Å silica, C 18, 5 µm, 4.6 x 250 mm L1 208HS54 90Å silica, C 8, 5 µm, 4.6 x 250 mm L7 201HS5415 90Å silica, C 18, 5 µm, 4.6 x 150 mm L1 208HS5415 90Å silica, C 8, 5 µm, 4.6 x 150 mm L7 201HS104 90Å silica, C 18, 10 µm, 4.6 x 250 mm L1 218TP54 300 Å silica, C 18, 5 µm, 4.6 x 250 mm L1 214TP54 300 Å silica, C 4, 5 µm, 4.6 x 250 mm L26 208TP54 300 Å silica, C 8, 5 µm, 4.6 x 250 mm L7 219TP54 300 Å silica, Phenyl, 5 µm, 4.6 x 250 mm L11 To order Vydac HPLC columns, please contact Vydac or your local Vydac distributor. Page 10
To order Vydac products or obtain information: contact Vydac by telephone at 1-800-247-0924 or (760) 244-6107. Fax (888) 244-6610 or (760) 244-1984. Email sales@vydac.com. or contact your local Vydac distributor Visit Vydac on the World Wide Web at http://www.vydac.com Copyright 1998, The Separations Group, Hesperia, CA, USA. All rights reserved. Vydac is a registered trademark of The Separations Group. Prices and specifications subject to change without notice.