Highly Sensitive Fluorescent pH Microsensors Based on the Ratiometric Dye Pyranine Immobilized on Silica Microparticles

Optical fluorescent pH sensors based on positively charged silica microparticles containing anionic pyranine molecules were developed by using a modified Stöber method with gradual immobilization of ratiometrically pH-sensing during the growth seed particles and an overall positive charge in one-step reaction. The overly pH-sensitive nature is preserved long-term stability ensured shell coating. These cytocompatible ratiometric can be used for sensing tracking applications where each microparticle observed individually due to resolvable size. More information found Communication A. Chandra, L. del Mercato et al. (DOI: 10.1002/chem.202101568).