Oxacillin methods

It was recognized quite some time ago that DTA analysis could be used to deduce the compatibility between a drug substance and its excipients in a formulation. The effect of lubricants on performance was as problematic then as it is now, and DTA proved to be a powerful method in the evaluation of possible incompatibilities. Jacobson and Reier used DTA to study the interaction between various penicillins and stearic acid [17]. For instance, the addition of 5% stearic acid to sodium oxacillin monohydrate completely obliterated the thermal events associated with the antibiotic. Since that time, many workers employed DTA analysis in the study of drug-excipient interactions, although the DTA method has been largely replaced by differential scanning calorimetry technology. 

Antisera to cloxacillin/oxacillin/dicloxacillin and cefuroxime were also produced by similar procedures and successfully utilized in methods for the detection of these antibiotics in milk (34). Unfortunately, a number of other -lactams including aminopenicillins and some cephalosporins were not amenable to this mixed anhydride procedure. Thus, a carrier protein derivatization procedure was used to allow cross-linking of cephalosporins, such as cephataxime that has an acetoxy side chain, to ovalbumin. Because acetoxy groups react readily with the heterocyclic nitrogen atoms, the latter were introduced into ovalbumin through the carbodiimide-mediated derivatization of protein carboxyl groups with amino-methylpyridine (34). 

D Hurtaud, B Delepine, P Sanders. Particle-beam liquid chromatography-mass spectrometry method with negative ion chemical ionization for the confirmation of oxacillin, cloxacillin and dicloxacillin residues in bovine muscle. Analyst 119 2731-2736, 1994. 

BenzylpenicUlin (PCG), phenoxymethylpeniciUin (PCV), oxacillin (MPIPC), cloxaciUin (MCIPC), nafcillin (NFPC), and dicloxacillin (MDIPC), aU of which are representative weakly acidic penicUlins, are widely used as veterinary drugs for livestock. We have reported, in our previous studies, the applicability of sample cleanup with an ion-exchange cartridge, in combination with ion-pair HPLC, for the analysis of ionizable compounds. We therefore applied the same technique to develop an analytical method for the quantitative determination of these residual penicillins in bovine muscle, kidney, and liver. ... 

A. (2004) A comparative evaluation of phenotypic and molecular methods for the detection of oxacillin resistance in coagulase-negative staphylococci. /. Infect. 

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