The impact of zwitterionic surfactants on optode-based nanosensors different fabrication approaches and sensing mechanisms.

In this work, we explored the impact of zwitterionic surfactants, sulfobetaine 16 (SB-16) and a PEG-phospholipid conjugate (DSPE-PEG), on nanosensor performance. We fabricated four sensors (for Na, K, Al, and O) and examined how these surfactants influenced various aspects, including fabrication methods, sensing mechanisms, and the incorporation of nanomaterials. Our results highlighted SB-16's role in enhancing selectivity in ion-exchange sensors (Na and K) while maintaining sensitivity akin to its PEG counterpart. The liquid-liquid extraction based sensors (Al) were unaffected by surfactant choice, while the O sensors that operate collisional quenching exhibited reduced sensitivity with SB-16 when compared to its PEG-based counterpart. Additionally, the SB-16 sensors proved adaptable to different fabrication approaches (SESE - single emulsion solvent evaporation and FNP - flash nanoprecipitation), showcased good cell viability and maintained a functional lifetime of at least five days. Furthermore, the use of quantum dots, we showed that it is possible to incorporate other nanomaterials into the sensing phase of SB-16 sensors. Future investigations could target enhancing the pH stability of zwitterionic surfactants to further advance their applicability in sensor technologies.