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:
Jul. 04, 1995
Filed:
Aug. 29, 1991
Samuel Schalkowsky, Chevy Chase, MD (US);
Spiral System Instruments, Inc., Bethesda, MD (US);
Abstract
A method for evaluating the comparative effect of growth-affecting substances, such as antimicrobial drugs or antibiotics, on different cultures of microorganisms is disclosed. The cultures are plated on the surface of a culture medium (12), such as agar, in adjacent at least partially separated tracks, such as tracks formed as Archimedes spirals. The cultures may be different concentrations of the same microbe or a test culture and a reference culture. The growth-affecting substances (22) are placed in contact with the culture medium on which the cultures have been plated preferably in the form of disks containing a powdered growth-affecting substance which dissolves and diffuses differentially into the culture medium to produce zones (24) of inhibition of growth extending radially outward from the disk. A comparison of the distance between the disk and the point of inhibition of the tracks of the different cultures which intersect the disk permits direct measurement of the comparative effects of the growth-affecting substance.