An Up Conversion Optical System Based on Mesoporous Silica Encapsulated Up-converting Nanoparticles Labeled Lateral Flow Immunoassay for Procalcitonin Quantification in Plasma

With the advancing of nanotechnology, nanomaterials based biosensors have been widely developed. Among them, optical biosensors stand out due to the high sensitivity and fast detection. In this paper, we demonstrate an up conversion luminescence (UCL) system based on immunochromatography by using core-shell mesoporous silica encapsulated up-converting nanoparticles (UCNPs@mSiO2) as probes for quantitative detection of Procalcitonin (PCT) in plasma. Compared with other structures, UCNPs@mSiO2 possess both great biocompatibility and strong luminous intensity, which is extremely ideal in immune detection. We further design a portable UCL reader for optical signal collecting and processing. As a result, the UCNPs@mSiO2 based lateral flow system can quantify PCT concentration with a range of 1-200 ng/mL, and the limit of detection is 0.5 ng/mL. We believe this UCL system possesses a promising potential in the monitoring and early diagnosis of infections.