Halochromic resorufin-GPTMS hybrid sol-gel: Chemical-physical properties and use as pH sensor fabric coating

Sol–Gel Treatment of Textiles for the Entrapping of an Antioxidant/Anti-Inflammatory Molecule: Functional Coating Morphological Characterization and Drug Release Evaluation

“…The sol was successfully applied on cotton surfaces and, after drying and curing, a stable and uniform PNPA-containing silica-based coating was obtained, as confirmed by morphological studies (SEM and AFM microscopy). As already shown in previous studies for halochromic dyestuff [20], the PEA derivative results firmly encapsulated into the 3D hybrid silica layer in absence of external stimuli (i.e., variable pH conditions), thanks to non-covalent and weak interactions (i.e., hydrogen bonds and van der Waals interactions) acting between the non-polar active molecule and the alkoxysilane hosting network.…”

“…In this regard, a GPTES-based sol was synthesized in acidic aqueous medium by addition of slight amount of HCl, as catalyst, and then added to a methanol solution containing the PNPA molecule. As reported in previous studies [15][16][17][18][19][20][21], the sol-gel synthesis leads to the formation of a hybrid polymeric 3D network through the opening of the epoxy ring of GPTES and interaction of the triethoxysilane end to form an extended polyethylene oxide network (PEO) [20], in whose holes the PNPA is physically and stably entrapped (Scheme 1). The so obtained G-PNPA functional sol was applied by padding on cotton fabrics and cured thermally with the aim to prepare a nano-hybrid coating for controlled release application (Scheme 2).…”

“…In our previous studies, we have already shown that nano-hybrid sol-gel-based coatings feature abrasion resistance, tensile strength and elongation properties of the treated fabrics [13,14]. These peculiar characteristics may be combined with a proper doping molecule, such as a dye [15][16][17][18][19][20][21], an antimicrobial [22], a hydrophobic [23][24][25] or a flame-resistant molecule [26,27], with the aim of improving the textile surface properties and making a functional nano-hybrid coating.…”

Recent Advances and Perspective on Design and Synthesis of Electrode Materials for Electrochemical Sensing of Heavy Metals

“…Sol–gel technology provides a simple way to produce 3D networks with high porosity, excellent physical rigidity, chemical inertness, and thermal stability . In sol–gel processing, the “sol” is often defined as the solution (liquid) phase containing suspension of small monomers, which evolves toward the formation of an infinite 3D network structure or discrete particles spreading uniformly throughout the liquid medium .…”

“…The fraction of solid phase is then obtained by removing the liquid phase with a number of phase separation process, for example centrifugation or simply sedimentation. A drying process with thermal treatment is necessary to enhance its mechanical properties and favor its further structure transformation . The sol–gel process combined with functional materials as conducting polymers and nanomaterials to build electrochemical sensing devices has the potentials to enhance electrical conductivity, slow response time, and sensitivity .…”