AUTOMATION OF A TECHNIQUE FOR DETERMINING BACTERIAL SENSITIVITY TO ANTIBIOTICS, VOLUME I.

Abstract

Several hundred bacterial growth curves were generated by the Lindberg-Reese automated instrument for testing sensitivity to antibiotics. The instrument monitors 24-hour growth in liquid media in the presence of graded levels of antibiotics. The curves, computer-plotted from instrument output tapes, reveal numerous details of growth and inhibition for E. coli, Streptococcus faecalis, Staphylococcus aureus, Proteus americanus and Vibrio metschnikovii. Intercomparison showed good reproducibility of fine details, sensitive and characteristic responses to presence of antibiotics, and small but significant effects of inoculum levels. As expected, the nature of the growth medium strongly affected the curve shapes. Further accumulation and analysis of such data should permit prediction of 24-hour minimum inhibitory concentrations from readings after only eight hours. Concepts of instrumentation were developed for the breadboard to be designed and constructed in the next phase and delivered at the end of the program. As compared with (1) the existent research instrument, and (2) the more advanced, originally proposed breadboard, the following principal improvements were visualized: (a) a means of operating continuously, while introducing and removing samples at will; (b) additon of a reference light source for cancelling photomultiplier drift; and (c) a new printout of growth data which is clear and concise and which may eliminate the need for computer processing. (Author)

Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1967
Accession Number
AD0652245

Entities

People

  • Christopher Miller
  • G. Reese
  • L. T. Carleton

Tags

DTIC Thesaurus Topics

  • Anti-Bacterial Agents
  • Automation
  • Bacteria
  • Computers
  • Inhibition
  • Instrumentation
  • Light Sources
  • Measuring Instruments
  • Reproducibility
  • Sensitivity
  • Staphylococcus Aureus
  • Streptococcus

Readers

  • Electronics Engineering
  • Microbial Pathology
  • Systems Analysis and Design