A validated HPLC method for the determination of pyridostigmine bromide, acetaminophen, acetylsalicylic acid and caffeine in rat plasma and urine

• Published in: Journal of pharmaceutical and biomedical analysis 2001-12, Vol.26 (5), p.939-947
• Main Authors: Abu-Qare, Aqel W, Abou-Donia, Mohamed B
• Format: Article
• Language: English
• Subjects: Acetaminophen; Acetaminophen - analysis; Acetaminophen - blood; Acetaminophen - urine; Acetylsalicylic acid; Analysis; Animals; Anti-Inflammatory Agents, Non-Steroidal - analysis; Anti-Inflammatory Agents, Non-Steroidal - blood; Anti-Inflammatory Agents, Non-Steroidal - urine; Aspirin - analysis; Aspirin - blood; Aspirin - urine; Biological and medical sciences; Caffeine; Caffeine - analysis; Caffeine - blood; Caffeine - urine; Calibration; Central Nervous System Stimulants - analysis; Central Nervous System Stimulants - blood; Central Nervous System Stimulants - urine; Chromatography, High Pressure Liquid; General pharmacology; Medical sciences; Pharmacology. Drug treatments; Pyridostigmine bromide; Pyridostigmine Bromide - analysis; Pyridostigmine Bromide - blood; Pyridostigmine Bromide - urine; Rats; Rats, Sprague-Dawley; Reproducibility of Results
• ISSN: 0731-7085; 1873-264X
• DOI: 10.1016/S0731-7085(01)00448-4

A method was developed for the separation and quantification of the anti-nerve agent pyridostgmine bromide (PB;3-dimethylaminocarbonyloxy- N-methyl pyridinium bromide), the analgesic drugs acetaminophen and acetylsalicylic acid, and the stimulant caffeine (3,7-dihydro-1,3,7-trimethyl-1 H-purine-2,6-dione) in rat plasma and urine. The compounds were extracted using C 18 Sep-Pak R cartridges then analyzed by high performance liquid chromatography (HPLC) with reversed phase C 18 column, and UV detection at 280 nm. The compounds were separated using gradient of 1–85% acetonitrile in water (pH 3.0) at a flow rate ranging between 1 and 1.5 ml/min in a period of 14 min. The retention times ranged from 8.8 to 11.5 min. The limits of detection were ranged between 100 and 200 ng/ml, while limits of quantitation were 150–200 ng/ml. Average percentage recovery of five spiked plasma samples were 70.9±9.5, 73.7±9.8, 88.6±9.3, 83.9±7.8, and from urine 69.1±8.5, 74.5±8.7, 85.9±9.8, 83.2±9.3, for pyridostigmine bromide, acetaminophen, acetylsalicylic acid and caffeine, respectively. The relationship between peak areas and concentration was linear over range between 100 and 1000 ng/ml. The resulting chromatograms showed no interfering peaks from endogenous plasma or urine components. This method was applied to analyze these compounds following oral administration in rats.