title: Chromatographic separation and chemical analysis of polymers formed by penicillin G.
abstract: To elucidate the chemical structures of penicillin polymers that may elicit an allergic reaction, a 25% aqueous solution of penicillin G potassium was kept standing in the dark at room temperature for 14 days and was then separated by gel filtration chromatography on Sephadex G-25. The fractions of Kav 0.0-0.3, 0.3-0.55 and 0.55-0.75 were designated fractions A, B and C, respectively. Chemical and spectral data indicated that fractions A and B had almost similar chemical structures, but differed in molecular weight. They consisted of equimolar phenylacetyl and thiazolidine moieties and showed a C:N:S ratio almost equal to that of penicillin G. Their degrees of polymerization were 10 for A and 3.2 for B. Comparison of 1H NMR and IR spectra and thin-layer chromatographic RF values with those of authentic standards showed that the main components of fraction C were N- formylpenicillamine , benzylpenilloic acid, benzylpenicilloic acid and benzylpenillic acid.
mesh_terms: D000485:Allergens; D002850:Chromatography, Gel / Q000379:methods; D002855:Chromatography, Thin Layer / Q000379:methods; D003624:Darkness; D004355:Drug Stability; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D010400:Penicillin G / Q000302:isolation & purification / Q000633:toxicity*; D011108:Polymers / Q000302:isolation & purification*; D013055:Spectrophotometry, Infrared / Q000379:methods
chemical_list: D000485:Allergens; D011108:Polymers; D010400:Penicillin G