Synthesis of functionalized polysiloxanes with nonconventional fluorescence and amphiphilicity by thiol-epoxy click reaction

Developing a new synthetic methodology for preparing functionalized polysiloxanes is highly desirable due to their promising applications in sensors, electronics, and bioimaging. Herein, we present the thiol-epoxy click reaction as an efficient approach for synthesizing novel functionalized polysiloxanes from epoxy-containing polysiloxanes and various thiol compounds. The resultant polysiloxanes exhibit remarkable nonconventional fluorescence, enabling efficient and selective detection of Fe3+ ions, with low limit of detections as low as 0.33 μM through fluorescence quenching. Notably, the quenched fluorescence can be restored by the addition of L-cysteine, facilitating the consecutive detection of Fe3+ ions and L-cysteine. Moreover, the introduction of β-OH groups into the polysiloxanes imparts intriguing amphiphilicity and further phase transfer ability, capable of effectively transferring the hydro-soluble organic dyes from the aqueous phase to chloroform. This simple strategy paves the way for developing more multifunctional polysiloxanes or other organosilicon materials.