The ongoing progress in the development of hydrogel technology has led to the emergence of materials with unique features and applications in medicine. The innovations behind the invention of nanocomposite hydrogels include new approaches towards synthesizing and modifying the hydrogels using diverse nanofillers synergistically with conventional polymeric hydrogel matrices. The present review focuses on the unique features of various important nanofillers used to develop nanocomposite hydrogels and the ongoing development of newly hydrogel systems designed using these nanofillers. This article gives an insight in the advancement of nanocomposite hydrogels for nanomedicine.

Ni nanostructures were synthesized using only castor oil (CSO), a natural polyol through green chemistry. CSO acts as multifunctional reagent (solvent, reducing agent, template, surface modifier) for the synthesis of the Ni nanostructures and imparts dye adsorption ability. The morphology of the nanostructures was found to be influenced by variations in the precursor concentration. A three molar concentration resulted in the formation of nanorods (ca. 11 × 75 nm) due to a higher nucleation rate as compared to growth rate, while a six molar concentration produces nanospheres (ca. 15 nm) due to a higher growth rate. The progress of the reaction, synthesis mechanism and surface functionalization of the Ni nanostructures were analyzed by Fourier transform infrared (FT-IR) spectroscopy. The interaction of Ni²⁺ with electron rich sites in the CSO resulted in the reduction of Ni²⁺ to Ni(0). The cubic lattice of the synthesized nanostructures, phase and preferred growth direction of the nanorods along the [200] plane were determined by correlation of X-ray diffraction (XRD) results with that of transmission electron microscopy (TEM) analysis. The adsorption ability of the magnetic Ni nanostructures was analyzed using parameters such as the adsorption kinetics (rate and order of adsorption), maximum adsorption capacity (250 mg g⁻¹ (nanospheres) and 142 mg g⁻¹ (nanorods)), effect of initial concentration of dye/adsorbent and contact time. The Langmuir and Freundlich adsorption isotherms were employed for an understanding of the nature (chemisorption or physisorption) of the dye adsorption. The magnetic nature of the adsorbent helps in the fast, economical separation of an adsorbed particle in comparison to non-magnetic dye adsorbents. The better and favorable adsorption (R_L value) of the dye on the synthesized Ni nanostructures, makes them a potential adsorbent for the removal of toxic dyes from industrial effluents.

Mechanical stability, surface hydrophobicity, and thermal stability of anticorrosive polymeric coatings play a significant role in technological and industrial fields. In view of this, the present study demonstrates the design of transparent organic–inorganic hybrid nanocomposite coatings with improved mechanical strength and barrier properties. Herein, a suspension was formulated containing in situ grown titania (–O–Ti–O–) from titanium isopropoxide (TIP), diglycidyl ethers of bisphenol-A (DGEBA), and polyamide (PA). TIP simultaneously acts as a condensation agent, bridging agent (–O–Ti–O), as well as an inorganic surface modifier to epoxy resin and increases the water contact angle due to topographical improvement via optimum cross-linked surface density. The surface, morphological, thermal, and electrochemical techniques highlight broader application areas for these hybrid polymeric materials. The lowest Icorr value of 2.5211 × 10⁻¹⁰ for DGE–TiO₂–PA hybrid coatings compared to those of DGE–PA (2.1029 × 10⁻⁷), CS (8.9131 × 10⁻⁵), and other reported coating systems in saline (3.5 and 5 weight% NaCl) environments projects DGE–TiO₂–PA as a potential anticorrosive coating material.