Biopolymer capped silver nanoparticles with potential for multifaceted applications

Biomedical and ecosafety assessment of marine fish collagen capped silver nanoparticles

In the rapidly evolving landscape of silver nanoparticles (Ag NPs) synthesis, the focus has predominantly been on plant-derived sources, leaving the realm of biological or animal origins relatively uncharted. Breaking new ground, our study introduces a pioneering approach: the creation of Ag NPs using marine fish collagen, termed ClAg NPs, and offers a comprehensive exploration of their diverse attributes. To begin, we meticulously characterized ClAg NPs, revealing their spherical morphology, strong crystalline structure, and average diameter of 5 to 100 nm. These NPs showed potent antibacterial activity, notably against S. aureus (gram-positive), surpassing their efficacy against S. typhi (gram-negative). Additionally, ClAg NPs effectively hindered the growth of MRSA biofilms at 500 μg/mL. Impressively, they demonstrated substantial antioxidant capabilities, out performing standard gallic acid. Although higher concentrations of ClAg NPs induced hemolysis (41.804 %), lower concentrations remained non hemolytic. Further evaluations delved into the safety and potential applications of ClAg NPs. In vitro cytotoxicity studies on HEK 293 and HeLa cells revealed dose-dependent toxicity, with IC50 of 75.28 μg/mL and 79.13 μg/mL, respectively. Furthermore, ClAg NPs affected seed germination, root, and shoot lengths in Mung plants, underscoring their relevance in agriculture. Lastly, zebrafish embryo toxicity assays revealed notable effects, particularly at 500 μg/mL, on embryo morphology and survival rates at 96 hpf. In conclusion, our study pioneers the synthesis and multifaceted evaluation of ClAg NPs, offering promise for their use as versatile nano therapeutics in the medical field and as high-value collagen-based nanobiomaterial with minimal environmental impact.

Recent advances in anticancer and antimicrobial activity of silver nanoparticles synthesized using phytochemicals and organic polymers

Development of eco-friendly synthetic methods has resulted in the production of biocompatible Ag NPs for applications in medical sector. To overcome the prevailing antibiotic resistance in bacteria, Ag NPs are being extensively researched over the past few years due to their broad spectrum and robust antimicrobial properties. Silver nanoparticles are also being studied widely in advanced anticancer therapy as an alternative anticancer agent to combat cancer in an effective manner. Keeping this backdrop in consideration, this review aims to provide an extensive coverage of the recent progresses in the green synthesis of Ag NPs specifically using plant derived reducing agents such phytochemicals and numerous other biopolymers. Current development in antimicrobial activity of Ag NPs against various pathogens has been deliberated at length. Recent advances in potent anticancer activity of the biogenic Ag NPs against various cancerous cell lines has also been discussed in detail. Mechanistic details of the synthesis of Ag NPs, their anticancer and antimicrobial action has also been highlighted.

Recent advances in guar gum based drug delivery systems and their administrative routes

Guar gum-based drug carrier systems have gained attention for the delivery of various therapeutic agents via different administration routes for attaining controlled and sustained release. Guar gum offers a safe and effective system for drug delivery due to its natural occurrence, easy availability, biocompatibility, and biodegradability, besides simple and mild preparation techniques. Furthermore, the possibility of using various routes such as oral, buccal, transdermal, intravenous, and gene delivery further diversify guar gum applications in the biomedical field. This review delineates the recent investigation on guar gum-based drug carrier systems like hydrogels, nanoparticles, nanocomposites, and scaffolds along with their related delivery routes. Also, the inclusion of data of the loading and subsequent release of the drugs enables to explore the noble and improved drug targeting therapies.

Study of the Properties of a Biodegradable Polymer Filled with Different Wood Flour Particles

Lignocellulosic wood flour particles with three different sizes were used to reinforce Solanyl^® type bioplastic in three compositions (10, 20, and 30 wt.%) and further processed by melt-extrusion and injection molding to simulate industrial conditions. The wood flour particles were morphologically and granulometric analyzed to evaluate their use as reinforcing filler. The Fuller method on wood flour particles was successfully applied and the obtained results were subsequently corroborated by the mechanical characterization. The rheological studies allowed observing how the viscosity was affected by the addition of wood flour and to recover information about the processing conditions of the biocomposites. Results suggest that all particles can be employed in extrusion processes (shear rate less than 1000 s⁻¹). However, under injection molding conditions, biocomposites with high percentages of wood flour or excessively large particles may cause an increase in defective injected-parts due to obstruction of the gate in the mold. From a processing point of view and based on the biocomposites performance, the best combination resulted in Solanyl^® type biopolymer reinforced with wood flour particles loaded up to 20 wt.% of small and medium particles size. The obtained biocomposites are of interest for injected molding parts for several industrial applications.

Remarkable SERS Detection by Hybrid Cu2O/Ag Nanospheres

Cu₂O nanospheres (NSs) were synthesized by modifying the glucose reduction method. Based on this method, Cu₂O/Au (Ag) NSs were further prepared by in situ reduction of HAuCl₄ (via electron beam evaporation of Ag). With Rhodamine 6G (R6G) as probe, the surface-enhanced Raman scattering (SERS) characteristics of the three samples were systematically studied. The experiment results showed that the enhancement factor (EF) of Cu₂O/Au (Ag) NSs as 1.25 × 10⁸ (2.74 × 10⁹) and the ultralow detection limit (LOD) as 8.07 × 10^-12 (1.13 × 10^-13) M for R6G. The excellent performance of SERS may be due to the charge transfer (CT) between metal-semiconductor (MS) molecules and the strong electromagnetic field (E-field) of each hot spot. In addition, discrete dipole approximation (DDA) simulations were performed to simulate the E-field enhancement of the Cu₂O and Cu₂O/Au (Ag) NSs in a three-dimensional (3D) configuration. These further supported that the high SERS performance for R6G is because of the powerful E-field coupling between neighboring Au (Ag) NPs and the surface plasmon resonance (SPR) effect. The Cu₂O/Ag NSs have potential in applications such as biomedicine, food safety, and environmental monitoring because of their high sensitivity and good reproducibility.

Microscopic Techniques for the Analysis of Micro and Nanostructures of Biopolymers and Their Derivatives

Natural biopolymers, a class of materials extracted from renewable sources, is garnering interest due to growing concerns over environmental safety; biopolymers have the advantage of biocompatibility and biodegradability, an imperative requirement. The synthesis of nanoparticles and nanofibers from biopolymers provides a green platform relative to the conventional methods that use hazardous chemicals. However, it is challenging to characterize these nanoparticles and fibers due to the variation in size, shape, and morphology. In order to evaluate these properties, microscopic techniques such as optical microscopy, atomic force microscopy (AFM), and transmission electron microscopy (TEM) are essential. With the advent of new biopolymer systems, it is necessary to obtain insights into the fundamental structures of these systems to determine their structural, physical, and morphological properties, which play a vital role in defining their performance and applications. Microscopic techniques perform a decisive role in revealing intricate details, which assists in the appraisal of microstructure, surface morphology, chemical composition, and interfacial properties. This review highlights the significance of various microscopic techniques incorporating the literature details that help characterize biopolymers and their derivatives.

Au-Pd bimetallic nanoparticles embedded highly porous Fenugreek polysaccharide based micro networks for catalytic applications

Currently, metallic nanoparticles possessing versatile heterogeneous catalytic functionality such as in hydrogenation, water splitting, hydrogen production and CO₂ reduction for global pollution remediation have been paid great attentions due to their high chemical stability, superior activity and unique electrical and optical properties. However, the gradual degradation of their catalytic activity on multiple usage limits the monometallic nanoparticles to industrial applications. Herein, we fabricated the highly porous fenugreek polysaccharide assisted green synthesis of AuPd nanostructures for heterogeneous catalytic hydrogenation of the industrial usable highly toxic 4-nitrophenol to the medicinally useful 4-aminophenol. The aqueous method developed in the present work is environmentally friendly, simple and low-cost procedure. The fabricated bimetallic porous AuPd nanostructures characterized using SEM, TEM, UV-Vis, XRD, XPS and FTIR analysis. The catalytic activity of the synthesized nanostructures was studied for the heterogeneous hydrogenation of 4-nitrophenol to 4-aminophenol in presence of NaBH₄, and the catalytic kinetic for the hydrogenation was analyzed via an UV-Vis spectrometer.

Silver Nanoparticles: Technological Advances, Societal Impacts, and Metrological Challenges

Silver nanoparticles (AgNPs) show different physical and chemical properties compared to their macroscale analogs. This is primarily due to their small size and, consequently, the exceptional surface area of these materials. Presently, advances in the synthesis, stabilization, and production of AgNPs have fostered a new generation of commercial products and intensified scientific investigation within the nanotechnology field. The use of AgNPs in commercial products is increasing and impacts on the environment and human health are largely unknown. This article discusses advances in AgNP production and presents an overview of the commercial, societal, and environmental impacts of this emerging nanoparticle (NP), and nanomaterials in general. Finally, we examine the challenges associated with AgNP characterization, discuss the importance of the development of NP reference materials (RMs) and explore their role as a metrological mechanism to improve the quality and comparability of NP measurements.