Single-Bacterium Diagnosis via Terahertz Near-Field Dielectric Nanoimaging
Jie Zhou, Xiaoqiuyan Zhang, Xingxing Xu, Yuanpei Wei, Tianyu Zhang, Fu Tang, Yanyu Wei, Yubin Gong, Xuequan Chen, Tianwu Wang, Yunxia Wang, Marc Lamy de la Chapelle, Jianjun Li, Xiang Zhao, Weiling Fu, Min Hu
Abstract
Single-bacterium diagnostic methods with unprecedented precision and rapid turnaround times are promising tools for facilitating the transition from empirical treatment to personalized anti-infection treatment. Terahertz (THz) radiation, a cutting-edge technology for identifying pathogens, enables the label-free and non-destructive detection of intermolecular vibrational modes and bacterial dielectric properties. However, this individual dielectric property-based detection and the mismatched spatial resolution are limited for the single-bacterium identification of various species of pathogens. Here, we demonstrate a single-bacterium THz dielectric nanoimaging (STDN) strategy by customized THz scattering-type scanning near-field optical microscopy. The THz nanoimages of bacteria are explained and confirmed by theoretical modeling and near-field measurement. By synchronously tracking the bacterial intrinsic dielectric property and extrinsic morphology, the strategy achieved 99.3% and 91.6% accuracy in species identification and antibiotic susceptibility testing with the trained classifier within 2 hours. This proof-of-concept STDN strategy may propel precise bacterial infection management and help to counteract antibiotic resistance.