The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 23, 1993
Filed:
Jun. 03, 1991
Kirk C Chen, Seattle, WA (US);
Other;
Abstract
A novel colorimetric method for beta-lactamase assay and its applications are disclosed. The novel assay method for beta-lactamase is based on the discovery described in this invention. The chromophore formed by oxidation of either the N-alkyl derivative of p-phenylenediamine or the 3,3',5,5'-tetraalkyl derivative of benzidine can be decolorized by the open beta-lactam ring end product resulting from the hydrolysis of a penicillin in the presence of a mercury-containing compound. The same chromophore can be decolorized by the open beta-lactam ring end product resulting from the hydrolysis of a cephalosporin in either the presence or the absence of the mercury-containing compound. None of the intact beta-lactam antibiotics can decolorize the chromophore in either the presence or the absence of the mercury-containing compound. The final concentration of the mercury-containing compound in the decolorization mixture ranges from approximately 0.005 mM to approximately 3 mM, and the pH of the decolorization mixture ranges from 3.5 to 8.0. Additional applications derived from coupling this novel assay method to methods in the art include: a method for specific detection of microbial beta-lactamases; a method for simultaneous detection of microbial cytochrome c oxidase systems and penicillinases, and its application to simultaneous presumptive identification of Neisseria gonorrhoeae in urethral exudates, and differentiation of the infecting gonococci into penicillinase-producing N. gonorrhoeae and non-penicillinase-producing N. gonorrhoeae; and a simultaneous assay method for peroxidase and penicillinase.