In the present work, a multiple-stimuli-responsive hydrogel has been synthesized via polymerization of acrylamide (AAm) and N-hydroxy methyl acrylamide (HMAm) on β-cyclodextrin (β-CD). The synthesized hydrogel β-CD-g-(pAAm/pHMAm) exhibited various striking features like ultrahigh stretchability (>6000%), flexibility, stab resistivity, self-recoverability, electroresponsiveness, pressure-responsiveness, adhesiveness, and high transparency (>90%). Besides, the hydrogel has demonstrated enhanced biocompatibility, UV resistance, and thermoresponsive shape memory behaviors. On the basis of these attractive characteristics of the hydrogel, a flexible pressure sensor for the real-time monitoring of human motion with superior biocompatibility and transparency was fabricated. Moreover, due to the nanofibrillar surface morphology of the β-CD-g-(pAAm/pHMAm) hydrogel, the sensor based on the gel exhibited high sensitivity (0.053 kPa–1 for 0–3.3 kPa). The flexible sensor demonstrates very fast response time (130 ms-210 ms) with adequate stability (5000 cycles). Interestingly, the sensor can rapidly sense both robust (index finger and wrist) motions as well as tiny (swallowing and phonation) physiological actions. In addition, this adhesive hydrogel patch also acts as a potential carrier for the sustained topical release of (∼80.8% in 48 h) the antibiotic drug gentamicin sulfate.

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A unique facile process has been adopted for fast assembly of a poly(N-vinyl imidazole) cross-linked β-cyclodextrin hydrogel through microwave-assisted free radical polymerization, using N,N′-methylenebis(acrylamide) cross-linker. The copolymer possesses positive surface charge, one of the characteristic properties of an ideal hemostatic hydrogel. The functionalized imidazole-based hydrogel demonstrates rapid, superior blood coagulation kinetics under in vitro and in vivo conditions. On application to a major renal arterial hemorrhagic model, this hydrogel shows better blood clotting kinetics, leading to complete hemostasis in as few as ∼144 ± 7 s. Additionally, 350 μL of whole blood was clotted instantly, in ∼35 s, and therefore, reinforcing its hemostatic potential. The hydrogel demonstrates excellent biocompatibility, when seeded with human dermal fibroblast cells, retaining the native property of its predecessor. In addition, the hydrogel presents excellent hemocompatibility when tested with whole blood with the highest hemolytic ratio of 1.07 ± 0.05%. Moreover, it also demonstrates potential as a carrier for sustained release of an anesthetic drug, lidocaine hydrochloride monohydrate (∼83% in 24 h). The rapid hemostatic behavior of the hydrogel is coupled with its cytocompatibility and hemocompatibilty properties along with controlled drug release characteristics. These behaviors evidently demonstrate it to be an excellent alternative for a superior hemostatic material for severe hemorrhagic conditions.

Metal/metal oxide nanoparticles have long been used as an antibacterial substitute, but fabrication of an effective carrier or delivery matrix for achieving a sustain release profile with high bactericidal efficacy alongwith good cytocompatibility is still an unresolved challenge. Herein, the study demonstrates a facile and unique route to fabricate a hierarchical nanobiocomposite with effective loading of ZnO/silver nanoparticles (Ag–NPs) in order to attain excellent bactericidal efficacy with good and sustainable release profile. Surface functionalized eggshell membranes (ESM) were deployed as three-dimensional loading matrices for efficient loading of ZnO/Ag–NPs. A simple sonochemical guided approach was adopted to synthesize ZnO nanoflakes in situ onto the microfibrous ESM and decorate it with Ag–NPs to fabricate a nanobiocomposite. Microstructural analysis confirms successful anchorage of ZnO nanoflakes and Ag–NPs on microfibrous eggshell membrane thus reinstating hierarchical morphology of the nanobiocomposites. FT-IR spectra confirms the biochemical composition whereas XPS analysis ratifies the interaction between ZnO and Ag–NPs further substantiating metallic state of Ag. ICP-MS studies affirms excellent and sustainable release profile of nanoparticles from the nanobiocomposites. Owing to the synergistic activity of ZnO/Ag–NPs, the nanobiocomposites demonstrated exceptional bactericidal activity against Gram-negative, E. coli or P. aeruginosa, and Gram-positive, S. aureus or B. subtilis, bacterial cells. Moreover, inherent antibacterial property of microfibrous natural ESM contributes positively toward the overall bactericidal activity. Further, a direct exposure of nanobiocomposites with NIH 3T3 cells revealed the biocompatible nature of developed matrices. Prolonged exposure also indicated that the 3T3 cells tend to adhere onto the microfibrous nanobiocomposite without any observable deformation in cellular morphology. The architectural tribology and excellent bactericidal performance of the nanobiocomposites along with its cytocompatible nature manifests its application as an alternate platform for varying biomedical applications.