Monitoring of benzylpenicillin in ovine milk by HPLC.
A method for determination in vivo of the benzylpenicillin residues in ovine milk at low levels was described. Two groups of Sardinian breed sheep were treated with a dose of penicillin G sodium salt by intramammary infusion and intramuscular administration respectively. The residues were detected by isocratic HPLC method of the extract obtained from a previous cleanup procedure. Linear calibration plots were obtained over a large concentration range of 1 mg ml-1 -10 ng ml-1, with correlation coefficients greater than 0.998. Recoveries between 78.6 and 87.3% were obtained. Limit of detection (LOD) and limit of determination (LOQ) were 2.6 and 8.8 ng ml-1 respectively. This method would be useful for routine monitoring of penicillin G residues in ovine dairy milk.
Istituto di Analitica Farmaceutica, Facoltà di Farmacia, Università degli Studi di Sassari, Italy. anfarm@ssmain.uniss.it
G
G
Boatto
R
R
Cerri
A
A
Pau
M
M
Palomba
G
G
Pintore
M G
MG
Denti
D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D008892:Milk / Q000737:chemistry*; D010400:Penicillin G / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012756:Sheep; D013056:Spectrophotometry, Ultraviolet
D010400:Penicillin G