Influences of growth media and culture time on the SERS spectral patterns of three common pathogenic bacteria: A comparative analysis
Abstract
Surface-enhanced Raman spectroscopy (SERS) has emerged as a powerful tool for clinical microorganism identification, offering significant advantages over traditional culture-based methods, including minimal sample requirements, rapid detection, and operational simplicity. However, bacterial SERS spectra are subject to variations due to various experimental factors. To evaluate the influence of two key factors, growth media and culture time, on bacterial SERS spectra, we inoculated three important clinical pathogens, Escherichia coli , Staphylococcus aureus , and Pseudomonas aeruginosa , on three solid growth media (BHI, LB, and TSB) and acquired their SERS spectra at three time points (6 h, 12 h, and 24 h) for analysis. The clear differentiation of SERS spectra in the clustering analysis across various media and time points confirms that both culture time and growth media lead to significant changes of SERS spectra. Using the best-performing convolutional neural network (CNN) models, we achieved a classification accuracy of 98.11 % in distinguishing bacterial species across varying growth media and time points, with an area under the curve (AUC) of 99.76 %. Notably, temporal factor exerted greater impact than media types on SERS spectral signatures because classification accuracy reached 98.30 ± 1.65 % for bacteria collected at identical time points, compared to 91.29 ± 2.31 % under identical media conditions ( p = 0.0128). These findings underscore the critical need for standardized protocols, consistent growth media and culture time, to ensure spectral reproducibility and enhance the reliability of diagnostics in SERS-based microbial identification in medical laboratories.
Document Type
Journal Article
Date of Publication
3-5-2026
Volume
348
PubMed ID
41138611
Publication Title
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy
Publisher
Elsevier
School
Nutrition and Health Innovation Research Institute / School of Medical and Health Sciences
Funders
Research Foundation for Advanced Talents of Guangdong Provincial People's Hospital (KY012023293)
Copyright
subscription content
Comments
Luan, L., Tang, J., Luo, Y., Ru, X., Luo, Y., Yao, Y., Liu, S., Gu, B., & Wang, L. (2025). Influences of growth media and culture time on the SERS spectral patterns of three common pathogenic bacteria: A comparative analysis. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 348. https://doi.org/10.1016/j.saa.2025.127078