Mass spectrometric detection method for microbial drug sensitivity

Abstract

The invention discloses a mass spectrometric detection method for microbial drug sensitivity. The mass spectrometric detection method comprises the following steps: setting an antibiotic treatment group and an antibiotic-free treatment group, incubating and culturing to-be-detected microorganisms by using a culture medium containing antibiotics in the antibiotic treatment group, and incubating and culturing to-be-detected microorganisms by using a culture medium without antibiotics in the antibiotic-free treatment group; respectively adding internal labels into two groups of incubated and cultured samples, then carrying out mass spectrometric detection to obtain spectrograms, respectively calculating the areas under curves of the spectrograms of the antibiotic treatment group and the antibiotic-free treatment group, and calculating RGR; and determining the drug resistance or sensitivity of the to-be-detected microorganisms to the corresponding antibiotics according to the critical point of the RGR value. The mass spectrometric detection method for microbial drug sensitivity does not need to pre-judge the drug resistance mechanism of microorganisms, and is high in sensitivity, short in detection time, free of addition of any isotope, low in cost and simple in test steps.

Description

technical field [0001] The invention relates to the technical field of drug sensitivity detection. More specifically, it relates to a mass spectrometry detection method for microbial drug susceptibility. Background technique [0002] The traditional microbial drug susceptibility test method is to mix live microorganisms and antibiotics in a liquid medium, and then culture them in an automatic heating incubator. The instrument will give a positive alarm according to the turbidity of the liquid medium, that is, there is After the microorganism grows, the turbidity increases. When the turbidity increases to the detection range of the instrument, the instrument can report positive, indicating that the microorganism is resistant to the antibiotic. Otherwise, the instrument does not alarm, indicating that the microorganism does not grow in the medium containing the antibiotic. It means that the microorganisms are sensitive to this kind of antibiotic. The positive alarm time requi...

AI Technical Summary

Problems solved by technology

There are many drug resistance mechanisms of bacteria (including Mycobacterium tuberculosis), and the current MALDI-TOF-MS detection method can only study one of them, and the drug resistance mechanism cannot be judged in advance for samples

Although some drug-resistant enzymes produced can be determined, their molecular weights are too large to be detected by mass spectrometry (mass of some drug-resistant enzymes > 30 000 Da); while research on products requires mass spectrometry to have ultra-high sensitivity in the small molecule range (antibiotics The mass is generally <1000Da), which often requires two types of mass spectrometers to detect large molecules and small molecules at the same time. At present, there is basically no mass spectrometer that can achieve high resolution in the detection range of large molecules and small molecules at the same time

In addition, there are some other methods (such as PCR method) for the study of drug resistance genes of Mycobacterium tuberculosis, which are complex in operation, high in contamination rate, poor in biological safety, and poor in sample throughput.

Images