Silk proteins, viz., sericin, fibroin and their modified forms etc., have been thoroughly researched as natural biopolymers for the development of varied nanomaterials exhibiting diverse biomedical applications. The silk proteins are extracted from the cocoons by degumming and treatment with soaps, followed by dissolution and dialysis against water. These proteins exhibit distinct mechanical and physicochemical characteristics including biocompatibility, controlled biodegradability, self-assembling traits, chemical modifiability, and adaptability, thus making it an ideal drug delivery vehicle. In this regard, silk protein-derived drug delivery systems have been reported as efficient carrier to encapsulate and stabilize the wide variety of pharmacological molecules, enzymes, proteins, vaccines, and even DNA, allowing them to remain active for a longer period of time. Further, different delivery carriers researched employing these proteins for multitude of applications include hydrogels, sponges, fibres, scaffolds and particulate delivery systems. Additionally, the chemical modification of silk proteins has further opened avenues for development of other modified silk proteins with improved physicochemical traits and hence exhibiting enormous potential in development of varied bioenhanced carrier systems. The current article thus provides the holistic information of characteristics, types of silk protein-based delivery carriers, and their fabrication techniques, while emphasizing the applications of different silk proteins in biomedicine and drug delivery.

Based on the modified cross-linking of the degradable natural polymers chitosan oligosaccharides (COS) and gelatin (GEL) via introduction of a functional bridge 3,3\'-dithiodipropionic acid, this study constructed an environmentally responsive dinotefuran (DNF) delivery system (DNF@COS-SS-GEL). The introduction of the disulfide bond (-S-S-) endowed DNF@COS-SS-GEL with redox-responsive properties, allowing for the rapid release of pesticides when stimulated by glutathione (GSH) in the simulated insect. Compared with commercial DNF suspension concentrate (DNF-SC), DNF@COS-SS-GEL showed superior wet spreading and retention performance on cabbage leaves with a reduced contact angle (57°) at 180 s and 4-fold increased retention capacity after rainfall washout. Nanoencapsulation effectively improved the UV-photostability with only a 31.4% decomposition rate of DNF@COS-SS-GEL at 96 h. The small scale and large specific surface area resulted in excellent uptake and transportation properties in plants as well as higher bioactivity against Plutella xylostella larvae. This study will help promote sustainable agricultural development by reducing environmental pollution through improved pesticide utilization.

Konjac glucomannan (KGM) as an emerging natural polymer has attracted increasing interests owing to its film-forming properties, excellent gelation, non-toxic characteristics, strong adhesion, good biocompatibility, and easy biodegradability. Benefiting from these superior performances, KGM has been widely applied in the construction of multiple composite materials to further improve their intrinsic performances (e.g., mechanical strength and properties). Up to now, KGM-based composite materials have obtained widespread applications in diverse fields, especially in the field of biomedical. Therefore, a timely review of relevant research progresses is important for promoting the development of KGM-based composite materials. Innovatively, firstly, this review briefly introduced the structure properties and functions of KGMs based on the unique perspective of the biomedical field. Then, the latest advances on the preparation and properties of KGM-based composite materials (i.e., gels, microspheres, films, nanofibers, nanoparticles, etc.) were comprehensively summarized. Finally, the promising applications of KGM-based composite materials in the field of biomedical are comprehensively summarized and discussed, involving drug delivery, wound healing, tissue engineering, antibacterial, tumor treatment, etc. Impressively, the remaining challenges and opportunities in this promising field were put forward. This review can provide a reference for guiding and promoting the design and biomedical applications of KGM-based composites.

Trinitroglycerin (TNG) with remarkable angiogenic, antibacterial, and antioxidative activity is a promising candidate to govern wound healing capacity. However, its clinical administration is limited due to associated complications and NO short half-life. In the current study, TNG-loaded chitosan nanogels (TNG-Ngs) were examined in-vitro and in-vivo to gain insight into their clinical application. We prepared TNG-Ngs and characterized their physiochemical properties. The potential of TNG-Ngs was assessed using biocompatibility, scratch assay, and a full-thickness skin wounds model, followed by histopathological and immunohistochemistry examinations. TNG-Ngs particle size 96 ± 18 and definite size distribution histogram. The loading capacity (LC) and encapsulation efficiency (EE) of prepared TNG-Ngs were 70.2 % and 2.1 %, respectively. The TNG-Ngs samples showed enhanced migration of HUVECs with no apparent cytotoxicity. The topical use of TNG-Ngs200 on the wounds revealed a complete wound closure ratio, skin component formation, less scar width, remarkable granulation tissue, promoted collagen deposition, and enhanced the relative mean density of α-SMA and CD31. TNG-Ngs accelerated wound healing by promoting collagen deposition and angiogenic activity, as well as reducing inflammation. The findings indicated that TNG-Ngs is expected to be well vascularized in the wound area and to be more effective in topical therapy.

Hydrogels have several characteristics, including biocompatibility, physical similarity with the skin\'s extracellular matrix, and regeneration capacity. Cell migration and proliferation are facilitated by natural polymers such as gelatin (Gel) and carboxymethyl cellulose (CMC). Gelatin dressing acts as a structural framework for cell migration into the wound area, stimulating cell division and promoting granulation tissue formation. Omega-3 fatty acids from fish oil may prevent wound infection and improve the healing of wounds in the early stages. We studied the preparation of wound dressing containing Omega-3 and its ability to heal wounds. In this study, CMC-Gel hydrogels containing different concentrations of Omega-3 were investigated in full-thickness wounds. After the fabrication of the hydrogels by using surfactant (tween 20) and microemulsion method (oil in water), various tests such as SEM, Water uptake evaluation, weight loss, cell viability, blood compatibility, and in vivo study in rat cutaneous modeling during 14 days were performed to evaluate the properties of the fabricated hydrogels. The analysis of the hydrogels revealed that they possess porous structures with interconnected pores, with an average size of 83.23 ± 6.43 μm. The hydrogels exhibited a swelling capacity of up to 60% of their initial weight within 24 h, as indicated by the weight loss and swelling measurements. Cell viability study with the MTT technique showed that no cytotoxicity was observed at the recommended dosage, however, increasing the amount of omega-3 caused hemolysis, cell death, and inhibition of coagulation activity. An in vivo study in adult male rats with a full-thickness model showed greater than 91% improvement of the primary wound region after 2 weeks of treatment. Histological analysis demonstrated Omega-3 in hydrogels, which is a promising approach for topical skin treatment to prevent scar, and has shown efficacy as wound dressing by improving the repair process at the defect site.

Diabetes-related slow healing of wounds is primarily driven by bacterial infections and angiogenesis disorder and presents a substantial hurdle in clinical treatment. To solve the above problems, an advanced multifunctional hydrogel system based on natural polymer was created here to facilitate wound healing in patients with chronic diabetes. The prepared dressing was composed of an outer hydrogel containing polyvinyl alcohol and hydroxypropyl methyl cellulose in dimethyl sulfoxide and water as binary solvents, and an inner hydrogel containing chitosan quaternary ammonium salt, flaxseed gum, and polyvinyl alcohol. Thus, a polysaccharide based bilayer hydrogel (BH) with superior mechanical strength and biocompatibility was created. This bilayer hydrogel could easily bind to dynamic tissue surfaces, thereby generating a protective barrier. Meanwhile, L-arginine-modified polyoxometalate (POM@L-Arg) nanoclusters were loaded in the inner hydrogel. They released NO when stimulated by the peroxide microenvironment of diabetic wounds. NO as a signal molecule regulated vascular tension and promoted cell proliferation and migration. Additionally, because of the synergistic effect of NO and the chitosan quaternary ammonium salt, the hydrogel system exhibited excellent antibacterial performance. The NO released reduced the levels of proinflammatory factors IL-6 and TNF-α in the diabetic wounds, which thus accelerated wound healing. In short, BH + POM@L-Arg is expected to serve as an ideal wound dressing as it exerts a good promotion effect on diabetes-related wound healing.

A superabsorbent hydrogel was prepared by the free-radical copolymerization of natural rubber (NR) latex with poly(acrylic acid) (PAA) at NR loadings up to 50 wt%. An NR/PAA hydrogel containing 40 wt% of NR (NR-40) had a water absorption capacity of 214 g/g (21,400 %) of its dry weight. The compressive modulus increased 512 % and sample integrity was improved due to the physical entanglement of NR chains. NR-40 hydrogel removed 97 % of methylene blue (MB) from the aqueous solution in 1 h (at initial concentrations of 10-1000 mg/L) and produced a maximum removal of 1191 mg MB/g of hydrogel at an initial MB concentration of 4500 mg/L. The adsorption of MB was an endothermic process. Fourier transform infrared spectroscopy indicated that hydrogen bonding and electrostatic interaction drove the process. After the in-situ incorporation of ZnO into NR-40, absorbed energy from sunlight generated active species that could photocatalytically degrade adsorbed MB in the hydrogel matrix. The scavenger tests indicated that superoxide radical anions and hydroxyl radicals were the main species for this process. The hydrogel composite material showed good stability and could be regenerated and reused over 10 cycles, degrading >80 % of the adsorbed dye. This novel natural-based hydrogel provides double functions of adsorption and photodegradation of toxic dyes without the requirement of chemicals and a separation process.

The elimination of pesticides from polluted water is critical due to their harmful environmental and biological impacts. Recently, there has been interest in utilizing natural polymer-based adsorbents as an eco-friendly approach to eliminate or reduce the levels of water pollutants. In this work, we synthesized an antimicrobial and magnetic bionanocomposite consisting of carboxymethyl gond katira-grafted- poly(3-aminobenzoic acid) with iron oxide and zinc oxide NPs (CMT-g-P3ABA/ZnO/Fe3O4) through an in situ polymerization reaction and examined for its ability to adsorb the pesticide acetamiprid (AP). The bionanocomposite was characterized using several analytical techniques, including spectroscopy; XRD presented the crystalline structure of ZnO/Fe3O4 in the CMT-g-P3ABA amorphous matrix. The ZnO/Fe3O4 partially aggregated formation and exhibited polyhedral crystal shapes was depicted by electron microscopy images, vibrating sample magnetometer (45.06 emu/g), porosimetry (5.52 m2/g), and thermal (Chair yield of approximately 43.83 %) and elemental analyses. Under various conditions, including solution pH (4-9), adsorbent dosage (0.005-0.025 g), time of contact (10-30 min), and pesticide preliminary concentration (200-400 mg/L) in 10 mL of the solution. Based on this research, Adsorption data were perfectly fitted by the Freundlich isotherm model with RAP2= 0.99038, while the pseudo-second-order (PSO) model well-explained adsorption kinetics with RAP2= 0.99847. AP adsorption to the CMT-g-P3ABA/ZnO/Fe3O4 bionanocomposite was successful due to hydrophobic interactions, hydrogen bonding, and π-π stacking. Furthermore, adsorption-desorption experiments demonstrated that the bionanocomposite could be regenerated after three reuse cycles without considerable loss of pesticide removal performance. The bionanocomposite also exhibited promising antimicrobial activity in contradiction to test bacteria.

The study involved preparing and applying edible nano-emulsion coatings containing hydroxypropyl methylcellulose (HPMC), beeswax (BW), and essential oils (thyme, cinnamon, clove, and peppermint) onto sweet cherries. The application was conducted at 4 °C, and the coated cherries were stored for 36 days. This research examines synthesized nano-emulsions physicochemical properties and antibacterial and antifungal activities (C1, C2, and C3). Additionally, it evaluates the quality parameters of control and coated sweet cherry samples. The features of the three edible coatings were assessed, and the findings from the zeta sizer, zeta potential, FTIR, and SEM analyses were deemed satisfactory. It was observed that the application of nano-emulsion coating C1 yielded positive results in maintaining quality attributes such as total suspended solids (TSS), total solids (TS), color, weight loss, respiration rate, firmness, total phenolic contents, and sensory evaluations. Nano-emulsion coating C1 demonstrated efficacy as an antibacterial and antifungal agent against foodborne pathogens E. coli and A. niger, respectively. The current research results are promising and applicable in food industries. The implications suggest that composite nano-emulsion, specifically nano-emulsion edible coatings, can be extensively and effectively used to preserve the quality and shelf life of fruits and vegetables. Furthermore, the environmental waste from conventional food packaging will be minimized using edible packaging applications.

Encapsulation of natural polymer pectin (Pec) into a zeolitic imidazolate framework-12 (ZIF-12) matrix via a simple chemical method toward anticancer agent gallic acid (GA) detection is reported in this work. GA, a natural phenol found in many food sources, has gained attention by its biological effects on the human body, such as an antioxidant and anti-inflammatory. Therefore, it is crucial to accurately and rapidly determine the GA level in humans. The encapsulation of Pec inside the ZIF-12 has been successfully confirmed from the physiochemical studies such as XRD, Raman, FTIR, and XPS spectroscopy along with morphological FESEM, BET, and HRTEM characterization. Under optimized conditions, the Pec@ZIF-12 composite exhibits wide linear range of 20 nM-250 μM with a detection limit of 2.2 nM; also, it showed excellent selectivity, stability, and reproducibility. Furthermore, the real sample analysis of food samples including tea, coffee, grape, and pomegranate samples shows exceptional recovery percentage in an unspiked manner. So far, there is little literature for encapsulating proteins, enzymes, metals, etc., that have been reported; here, we successfully encapsulated a natural polymer Pec inside the ZIF-12 cage. This encapsulation significantly enhanced the composite electrochemical performance, which could be seen from the overall results. All of these strongly suggest that the proposed Pec@ZIF-12 composite could be used for miniaturized device fabrication for the evaluation of GA in both home and industrial applications.