Photoluminescent BNCQD-Loaded Hydrogels for Real-Time Sensing, pH-Responsive Drug Release, and UV Protection

The advent of photoluminescent nanocomposites is unlocking paradigms in advanced biosensing, drug delivery, and regenerative medicine. This research reports a facile one-pot synthesis of phenol-functionalized boron nitride carbon quantum dots (BNCQDs) through both hydrothermal and solvothermal routes, yielding an underexplored class of zero-dimensional nanomaterials with intrinsic bioactive and optical attributes. Water-derived BNCQDs [BNCQDs(W)] exhibited a blue-green emission (λemission ≈ 510 nm at λexcitation = 420 nm) with nearly twice the photoluminescence intensity of their ethyl alcohol-derived counterparts, excellent thermal endurance with fluorescence retention across wide temperature gradients, and potent antioxidant and antibacterial activity. Leveraging these properties, BNCQDs(W) were integrated into photocurable methacrylated carboxymethyl cellulose/polyacrylamide semi-interpenetrating (semi-IPN) hydrogels via ultraviolet (UV) initiated polymerization, producing a viscoelastic network with optimized microporosity for prolonged water uptake and pH-responsive drug release. The optimal nanocomposite hydrogel combined strong mechanical resilience with 93.2% UVA, 98.2% UVB, and 99.8% UVC attenuation, sustained therapeutic release over 3 days with accelerated release at pH 8.5/7.4, linear real-time optical tracking of drug elution, and broad linear pH monitoring. Furthermore, digital light processing (DLP) printing enabled high-fidelity microporous architectures tailored for wound dressing and tissue regeneration. These multifunctional hydrogels unite the luminescence and bioactivity of BNCQDs with the structural adaptability of semi-IPN hydrogels, offering a scalable route to next-generation biomedical constructs with integrated sensing, protective, and therapeutic capabilities.