High-performance liquid chromatographic determination of penicillins by means of automated solid-phase extraction and photochemical degradation with electrochemical detection.
An automated precolumn exchange system for on-line solid-phase extraction (OPS-2) coupled to liquid chromatography with photochemical degradation and electrochemical detection was used for the determination of residual amounts of penicillin G, penicillin V, oxacillin, cloxacillin and dicloxacillin. A 5-10-fold increase in sensitivity was obtained when compared with direct UV detection of penicillins at 225 nm. The system is recommended for samples that have received an immunoaffinity clean-up. Analysis of bovine muscle tissue indicated, however, that this procedure could also be suitable for the determination of penicillin G at its maximum residue limit of 50 micrograms/kg even with conventional solvent partitioning for the first clean-up steps.
Lihl
S
S
Bergische Universität Gesamthochschule Wuppertal, Department of Food Chemistry (FB 9), Germany.
Rehorek
A
A
Petz
M
M
D000818:Animals; D001322:Autoanalysis; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D004563:Electrochemistry; D018482:Muscle, Skeletal / Q000737:chemistry; D010084:Oxidation-Reduction; D010406:Penicillins / Q000032:analysis* / Q000737:chemistry; D010777:Photochemistry; D012997:Solvents; D013056:Spectrophotometry, Ultraviolet
D010406:Penicillins; D012997:Solvents