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Single-molecule optofluidic microsensor with interface whispering gallery modes.

ABSTRACT: Label-free sensors are highly desirable for biological analysis and early-stage disease diagnosis. Optical evanescent sensors have shown extraordinary ability in label-free detection, but their potentials have not been fully exploited because of the weak evanescent field tails at the sensing surfaces. Here, we report an ultrasensitive optofluidic biosensor with interface whispering gallery modes in a microbubble cavity. The interface modes feature both the peak of electromagnetic-field intensity at the sensing surface and high-Q factors even in a small-sized cavity, enabling a detection limit as low as 0.3 pg/cm² The sample consumption can be pushed down to 10 pL due to the intrinsically integrated microfluidic channel. Furthermore, detection of single DNA with 8 kDa molecular weight is realized by the plasmonic-enhanced interface mode.

SUBMITTER: Yu XC

PROVIDER: S-EPMC8832994 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature

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Single-molecule optofluidic microsensor with interface whispering gallery modes.

Yu Xiao-Chong XC Tang Shui-Jing SJ Liu Wenjing W Xu Yinglun Y Gong Qihuang Q Chen You-Ling YL Xiao Yun-Feng YF

Proceedings of the National Academy of Sciences of the United States of America 20220201 6

Label-free sensors are highly desirable for biological analysis and early-stage disease diagnosis. Optical evanescent sensors have shown extraordinary ability in label-free detection, but their potentials have not been fully exploited because of the weak evanescent field tails at the sensing surfaces. Here, we report an ultrasensitive optofluidic biosensor with interface whispering gallery modes in a microbubble cavity. The interface modes feature both the peak of electromagnetic-field intensity ...[more]

PMID: 35115398

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