Continuous Preparation of Semiconducting Polymer Nanoparticles with Varied Sizes for Online Fluorescence Sensing via a Laser-Tailored 3D Microfluidic Chip

Authors：Hu, Ruixuan; Li, Xiaolong; Xu, Jian; Cheng, Ya; Zhang, Min^*; Shi, Guoyue

Source：Analytical Chemistry, 2023, 95(27): 10422-10429.

DOI：10.1021/acs.analchem.3c01779

• NANOPRECIPITATION
• DRUG
• PARTICLES
• MIXERS
• GLASS

Microfluidic chips are in criticaldemand for emerging applicationsin material synthesis and biosensing. Herein, we relied on ultrafastlaser-processing technology to fabricate a three-dimensional (3D)microfluidic chip, in which semiconducting polymer nanoparticles (SPNs)were continuously synthesized with tunable size and SPN-involved onlinefluorescence sensing was implemented. A homogeneous distribution ofSPNs can be readily realized due to the efficient mixing and powerfulvortices of the 3D microfluidic chip, which prevents SPNs from aggregatingthroughout the synthesis process. Moreover, in the optimized conditions,we unveiled unique SPNs with an ultrasmall particle size (<3 nm)and good monodispersity. By integrating with the high-performancefluorescence of SPNs and 3D microfluidic chip, we further developedan online sensing platform for ratiometric fluorescence assays ofH(2)O(2) and oxidase-catalyzed substrates (e.g.,glucose), in which a composite of SPNs and neutral red (NR) (SPNs/NR)was used as the mediator. The limit of detection (LOD) for H2O2 is 0.48 & mu;M, and the LOD for glucose is 3.33 & mu;Mvia the presented platform. This 3D microfluidic synthesis-and-sensingplatform provides a new avenue for the facile production of nanoparticlesand offers exciting prospects in the field of online sensing biomarkers.