The miniaturisation of biosensors has become crucial because of the great potential for in vivo biomarker detection and disease diagnostics as well as point-of-care testing during public health crises such as the coronavirus disease 2019 pandemic. Prof. Aping Zhang, Management Committee Member of the Photonics Research Institute (PRI), and his team members have invented an ultraminiature optical fiber-tip plasmonic biosensor for label-free biodetection.
This biosensor is based on plasmonic gold nanoparticles (AuNPs) directly printed on the end face of a standard multimode optical fiber in the visible light range. An in-situ precision photoreduction technique has been developed to additively print the micropatterns of size-controlled AuNPs. The AuNPs exhibit distinct localised surface plasmon resonance, the peak wavelength of which provides an ideal spectral signal for label-free biodetection. The fabricated optical fiber-tip plasmonic biosensor can detect not only antibodies, but also the SARS-CoV-2 mimetic DNA sequence at a concentration level of 0.8 pM. This ultraminiature fiber-tip plasmonic biosensor provides a cost-effective biodetection technology for a myriad of applications ranging from point-of-care testing to in vivo diagnosis of stubborn diseases.
The research results mentioned above has been published in the internationally renowned journal Biosensors and Bioelectronics (IF:12.54).
