Method for detecting trace live bacteria on basis of terahertz metamaterial

Abstract

The invention discloses a method for detecting trace live bacteria on the basis of a terahertz metamaterial. The method specifically comprises the steps that bacterial liquid is taken and added into the center of the terahertz metamaterial, and after drying is performed, a transmitted spectrum is measured with a terahertz time-domain spectrometer under the conditions that the temperature is 18 DEG C-25 DEG C and the relative humidity of a detection pool is lower than 2% by adopting a transmission mode, wherein the terahertz metamaterial is composed of a silicon substrate and metal open resonant rings which are periodically arranged on the silicon substrate. According to the method, the trace live bacteria can be quickly detected in an unmarked mode.

Description

technical field [0001] The invention belongs to the field of detection, and in particular relates to a method for detecting trace living bacteria based on a terahertz metamaterial. Background technique [0002] The traditional bacterial detection method is to identify the species according to the morphological and metabolic characteristics of the bacteria after culture. It usually takes several days to obtain the pathogenic species, and some slower-growing bacteria may take longer. Reactions based on nucleic acid amplification technology, such as PCR, can identify pathogenic bacteria types more quickly, but require complex nucleic acid extraction processes and preparation of matching primers in advance. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) can avoid nucleic acid extraction and directly detect pure colonies after culture, but the sensitivity is low, and the sensitivity is only 10 5 -10 6 CFU. More importantly, nucleic...

AI Technical Summary

Problems solved by technology

However, due to the masking effect of strong absorption of intracellular water, most propagule bacteria cannot show specific absorption peaks. The absorption coefficient spectrum is a relatively smooth curve, which can only be identified by numerical value.

Furthermore, due to the length-size mismatch between the terahertz wavelength (300 μm at 1 THz) and the bacterial size (typically 1–2 μm), a low scattering cross-section can result according to the principle of Rayleigh scattering

Therefore, it is necessary to find a way to solve the problem that the terahertz wavelength does not match the size of bacteria

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