Abstract
A simplified method of assaying mixtures of ampicillin and cloxacillin is presented. The method consists of cylinder-plate assays of appropriately diluted samples in three assay systems in which: (i) cloxacillin is measured, utilizing agar seeded with a penicillinase-producing Staphylococcus aureus; (ii) ampicillin is measured after the greatest dilution practicable, by use of agar seeded with Sarcina lutea; and (iii) the proportion of activity found in the second assay that remains after treatment with staphylococcal penicillinase is determined on agar seeded with S. lutea. The error was 4% or less when each system was run in quadruplicate, except when there was 10 or more times as much cloxacillin as ampicillin, in which case the greatest error was 12%. Mixtures of methicillin with benzylpenicillin or with ampicillin can also be quantitated by this method.
| Original language | Undefined/Unknown |
|---|---|
| Pages (from-to) | 468-470 |
| Number of pages | 3 |
| Journal | Applied Microbiology |
| Volume | 15 |
| Issue number | 3 |
| State | Published - 1967 |
Keywords
- Ampicillin/an [Analysis]
- Biological Assay
- Cloxacillin/an [Analysis]
- Methicillin/an [Analysis]
- Penicillin G/an [Analysis]
- Penicillinase/me [Metabolism]
- Sarcina/me [Metabolism]
- Staphylococcus/me [Metabolism]