Discrimination of selected species of pathogenic bacteria using near-infrared Raman spectroscopy and principal components analysis

Autor: de Siqueira e Oliveira, Fernanda S., Giana, Hector E., Silveira, Landulfo
Zdroj: Proceedings of SPIE; February 2012, Vol. 8214 Issue: 1 p821409-821409-7
Abstrakt: It has been proposed a method based on Raman spectroscopy for identification of different microorganisms involved in bacterial urinary tract infections. Spectra were collected from different bacterial colonies (Gram negative: E. coli, K. pneumoniae, P. mirabilis, P. aeruginosa, E. cloacaeand Gram positive: S. aureusand Enterococcussp.), grown in culture medium (Agar), using a Raman spectrometer with a fiber Raman probe (830 nm). Colonies were scraped from Agar surface placed in an aluminum foil for Raman measurements. After pre-processing, spectra were submitted to a Principal Component Analysis and Mahalanobis distance (PCA/MD) discrimination algorithm. It has been found that the mean Raman spectra of different bacterial species show similar bands, being the S. aureuswell characterized by strong bands related to carotenoids. PCA/MD could discriminate Gram positive bacteria with sensitivity and specificity of 100% and Gram negative bacteria with good sensitivity and high specificity.
Databáze: Supplemental Index