Hybrid materials based on chitosan functionalized with green synthesized copper nanoparticles: Physico-chemical and antimicrobial analysis

Green Synthesis of Antibacterial CuO Nanoparticles Based on the Synergy Between Cornu aspersum Snail Mucus and Ascorbic Acid

Many biologically active compounds have been identified in the mucus of the garden snail Cornu aspersum, which are effective in the treatment of several diseases such as cancer, ulcers, wounds, etc. The incorporation of these compounds into the green synthesis of copper nanoparticles (CuONPs-Muc) was demonstrated in our previous study. Based on the synergistic effect of two reducing agents-C. aspersum snail mucus and ascorbic acid (AsA)-on CuSO4.5H2O, which also act as stabilizers of the resulting compound, a new method for the "green" synthesis of CuONPs-Muc is presented. Using two reducing agents has several advantages, such as forming spherical nanoparticles with a diameter of about 150 nm and reducing the formation time of CuONPs-Muc to 3 h. Analyses by ultraviolet-visible spectroscopy (UV-Vis) and Fourier transform infrared spectroscopy (FT-IR) show the formation of CuONPs-Muc, composed of a mixture of copper and copper oxide. This was confirmed by scanning electron microscopy combined with energy-dispersive spectroscopy (SEM/EDS) and X-ray diffraction (XRD). Another important advantage of CuONPs obtained by the new method with two reducing agents is the stronger inhibitory effect on the bacterial growth of some Gram-positive and Gram-negative bacterial strains, compared to CuONPs-Muc prepared with only one reducing agent, i.e., a fraction of mucus with an MW > 20 kDa.

Unveiling the potential of chitosan-coated lipid nanoparticles in drug delivery for management of critical illness: a review

Chitosan (CT), a natural, cationic, chemically stable molecule, biocompatible, biodegradable, nontoxic, polysaccharide derived from the deacetylation of chitin, has very uniquely surfaced as a material of promise for drug delivery and biomedical applications. For the oral, ocular, cutaneous, pulmonary, and nose-to-brain routes, CT-coated nanoparticles (CTCNPs) have numerous advantages, consisting of improved controlled drug release, physicochemical stability, improved cell and tissue interactions, and increased bioavailability and efficacy of the active ingredient. CTCNPs have a broad range of therapeutic properties including anticancer, antiviral, antifungal, anti-inflammatory, antibacterial properties, treating neurological disorders, and other diseases. This has led to substantial research into the many potential uses of CT as a drug delivery vehicle. CT has also been employed in a wide range of biomedical processes, including bone and cartilage tissue regeneration, ocular tissue regeneration, periodontal tissue regeneration, heart tissue regeneration, and wound healing. Additionally, CT has been used in cosmeceutical, bioimaging, immunization, and gene transfer applications. CT exhibits a number of biological activities, which are the basis for its remarkable potential for use as a drug delivery vehicle, and these activities are covered in detail in this article. The alterations applied to CT to obtain the necessary properties have been described.

Chitosan nanocomposites as a nano-bio tool in phytopathogen control

Chitosan, an economically viable and versatile biopolymer, exhibits a wide array of advantageous physicochemical and biological properties. Chitosan nanocomposites, formed by the amalgamation of chitosan or chitosan nanoparticles with other nanoparticles or materials, have garnered extensive attention across agricultural, pharmaceutical, and biomedical domains. These nanocomposites have been rigorously investigated due to their diverse applications, notably in combatting plant pathogens. Their remarkable efficacy against phytopathogens has positioned them as a promising alternative to conventional chemical-based methods in phytopathogen control, thus exploring interest in sustainable agricultural practices with reduced reliance on chemical interventions. This review aims to highlight the anti-phytopathogenic activity of chitosan nanocomposites, emphasizing their potential in mitigating plant diseases. Additionally, it explores various synthesis methods for chitosan nanoparticles to enhance readers' understanding. Furthermore, the analysis delves into elucidating the intricate mechanisms governing the antimicrobial effectiveness of these composites against bacterial and fungal phytopathogens.

Synthesis and characterization of chitosan-copper nanocomposites and their catalytic properties for 4-nitrophenol reduction

Biopolymer-based copper nanoparticles (CuNPs) have become an area of significant interest due to their wide-ranging applications in a variety of fields. However, there remains a challenge in tailoring their morphologies and improving their properties. In this study, CuNPs were synthesized via wet chemical reduction using sodium hypophosphite monohydrate (NaH2PO2·H2O), l-ascorbic acid and chitosan. The effect of different synthesis conditions, including reaction pH, temperature, time, concentration of NaH2PO2·H2O, l-ascorbic acid and chitosan, as well as the deacetylation degree (DD) of chitosan, on the synthesis of CuNPs was investigated. The synthesized CuNPs were characterized by various analytical techniques. The catalytic properties of synthesized CuNPs were investigated for the reduction of 4-nitrophenol (4-NP) in the presence of sodium borohydride. The synthesis-morphology-catalytic activity relationship of CuNPs was discussed. The results suggested that the morphology of CuNPs could be adjusted by controlling the synthesis conditions. Chitosan DD significantly impacts the morphology of the synthesized CuNPs. As the chitosan DD decreased from 91.8 % to 52.3 %, the average particle size of synthesized CuNPs decreased from 43.9 ± 10.6 to 17.7 ± 5.9 nm and the shape changed from anisotropy to near-sphere. CuNPs synthesized using low DD (53.2 %) chitosan (CuNPs-N3) demonstrated the highest 4-NP conversion rate of 99.1 % and reaction rate constant of 0.3540 min-1. CuNPs-N3 was thermodynamically and kinetically more feasible than CuNPs synthesized with high DD chitosan. These findings provide important insights for further designing and developing hierarchical nanostructured CuNPs catalysts for broader applications.

The effects of double gelatin containing chitosan nanoparticles-calcium alginate coatings on the stability of chicken breast meat

The effects of gelatin coatings (2% and 4%) containing chitosan nanoparticles (ChNPs; 1% and 2%), in combination with calcium-alginate coatings (CA; 2%), on quality attributes and shelf life of chicken breast meat were evaluated at 4°C for 12 days. The results indicated that double-active gelatin-calcium alginate coatings had significant (p < .05) effects on moisture and protein content. Incorporation of ChNPs into double gelatin-CA coatings led to significant reduction (p < .05) in TBARS, pH, and TVB-N values at the end of storage. The counts of total viable count (TVC), coliforms, yeasts, and molds were significantly (p < .05) lower in all coated samples, particularly in treated samples by 4% gelatin containing 2% ChNPs + 2% CA coatings (6.85, 6.78, and 5.91 log CFU/g, respectively, compared with 8.35, 8.76, and 7.71 log CFU/g in control) at the end of keeping time. The results of sensory attributes showed that the coated samples had higher overall acceptability scores compared with the untreated samples. A synergistic relationship between the concentrations of gelatin and ChNPs was observed in maintaining the quality characteristics of meat samples during storage. Therefore, this study aims to evaluate the performance of double gelatin coating containing ChNPs in combination with CA coating in the storage quality improvement of chicken breast meat stored for 12 days at 4 °C to develop novel and practical coatings for meat and meat products.

Effect of nano-metal oxides (TiO2, MgO, CaO, and ZnO) on antibacterial property of (PEO/PEC-co-AAm) hydrogel synthesized by gamma irradiation

The global threat of infectious diseases and antibiotic resistance calls for the development of potent antimicrobial agents integrated with hydrogel for effective control and treatment. Hydrogel is advanced biomaterials compounds. Hydrogel is an advanced biomaterial compound that offers tunable physical and chemical properties, which can be tailored to specific biomedical applications. This study investigates the antibacterial properties of pectin/polyethylene oxide (PEC/PEO)-based poly acrylamide hydrogels containing 5 wt% nano-metal oxides (TiO2, CaO, MgO, and ZnO) synthesized through gamma irradiation at a dose of 30 kGy. This technique allows for sterilization and effectively incorporating the metal oxide nanoparticles within the hydrogel matrix. Characterization of the nanocomposites is performed using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Incorporating metal oxide nanoparticles induces noticeable changes in the FTIR spectra, confirming interactions between the nanoparticles and the hydrogel matrix. The antibacterial activity of the nanocomposites is evaluated against different bacteria, and the results demonstrate significant inhibitory effects, especially for MgO- and ZnO-hydrogel nanocomposites against P. mirabilis, S. aureus, P. aeruginosa, and C. albicans, highlighting their potential as antimicrobial agents. The 5 wt% of MgO, ZnO, TiO2 and CaO inside PEO/PEC-co-AAm hydrogel nanocomposites exhibited significant inhibitory effects, with a respective optical density at λ = 600 nm (OD600) values of 0.896 nm, 0.986 nm, 1.250 nm, and 1.980 nm compared to the control and hydrogel alone (OD600 values of 2.88 nm and 2.72 nm, respectively). The antibacterial activity of the (MgO-, ZnO-, TiO2-, and CaO-hydrogel) was enhanced, resulting in the inhibition of S. aureus growth by approximately 68.89 %, 65.86 %, 56.25 %, and 31.94 %, respectively. Incorporating nanoparticles into a hydrogel matrix introduces novelty by preventing their aggregation and synergistically enhancing the antibacterial activity. The hydrogel's porous structure and water content facilitate the physical entrapment of bacteria and promote proximity to the metal oxide nanoparticles, resulting in improved interaction and antimicrobial effectiveness. Moreover, the hydrogel ability to absorb and entrap resistance compounds released by bacteria, coupled with its ability to supply water for the generation of reactive oxygen species, further contributes to its antimicrobial properties.

Nanomaterial-Based Drug Delivery Systems for Pain Treatment and Relief: From the Delivery of a Single Drug to Co-Delivery of Multiple Therapeutics

The use of nanomaterials in drug delivery systems for pain treatment is becoming increasingly common. This review aims to summarize how nanomaterial-based drug delivery systems can be used to effectively treat and relieve pain, whether via the delivery of a single drug or a combination of multiple therapeutics. By utilizing nanoformulations, the solubility of analgesics can be increased. Meanwhile, controlled drug release and targeted delivery can be realized. These not only improve the pharmacokinetics and biodistribution of analgesics but also lead to improved pain relief effects with fewer side effects. Additionally, combination therapy is frequently applied to anesthesia and analgesia. The co-encapsulation of multiple therapeutics into a single nanoformulation for drug co-delivery has garnered significant interest. Numerous approaches using nanoformulation-based combination therapy have been developed and evaluated for pain management. These methods offer prolonged analgesic effects and reduced administration frequency by harnessing the synergy and co-action of multiple targets. However, it is important to note that these nanomaterial-based pain treatment methods are still in the exploratory stage and require further research to be effectively translated into clinical practice.