The power of sulfhydryl groups: Thiolated lipid-based nanoparticles enhance cellular uptake of nucleic acids

Green Synthesis of Antimicrobial Silver Nanoparticles (AgNPs) from the Mucus of the Garden Snail Cornu aspersum

The green synthesis of metal nanoparticles, mediated by extracts from various biological sources, leads to the formation of nanoparticles with unique characteristics and potential biomedical applications. In this study, a fraction of the mucus from the snail Cornu aspersum with MW > 20 kDa was used as a bioreducing and biostabilizing agent to obtain silver nanoparticles (AgNPs) in different pH media (pH 1.5, 3.5, and 7.0). The AgNPs were characterized using UV-visible spectroscopy, SEM, TEM, XRD, and FTIR. The synthesis at pH 1.5 and pH 3.5 in the presence of two reducing agents (i.e., the C. aspersum mucus fraction with MW > 20 kDa and ascorbic acid [AsA]) resulted in the formation of well-formed spherical nanoparticles (NPs) with larger sizes (20-80 nm) than the NPs obtained at pH 7.0 (20-60 nm) in the presence of only one reducing agent. Furthermore, the biosynthesized AgNPs significantly inhibited the growth of medically significant pathogens such as Gram-positive (Bacillus subtilis NBIMCC2353, Bacillus spizizenii ATCC 6633, Staphylococcus aureus ATCC 6538, and Listeria innocua NBIMCC8755) and Gram-negative (Escherichia coli ATCC8739, Salmonella enteitidis NBIMCC8691, Salmonella typhimurium ATCC 14028, Stenotrophomonas maltophilia ATCC 17666) bacteria compared to output mucus.

Near-infrared light-activated nanosystem endows scaffold with controllable nitric oxide release for peripheral nerve regeneration

The photosensitive S-nitrosocysteine (CysNO) could respond to light irradiation to produce nitric oxide (NO), exhibiting tremendous potential in accelerating peripheral nerve regeneration. However, its further application was limited by the burst release of NO and the requirement for ultraviolet excitation with low tissue penetration. Herein, a near-infrared-triggered NO controlled release nanosystem UCNP@ZIF-8/CysNO consisting of an upconversion nanoparticle (UCNP) core and zeolitic imidazolate framework-8 (ZIF-8) shell loading with CysNO was constructed, and then blended with poly-l-lactic acid powder to fabricate nerve scaffold by laser additive manufacturing technique. Once irradiated by near-infrared light, UCNP emitted ultraviolet light, triggering the S-NO cleavage of CysNO to generate NO, thereby achieving deep penetration therapy. In addition, the spatial confinement effect of 2-methylimidazole skeleton structure in ZIF-8 could effectively ensure the controlled release of NO. The Griess method test demonstrated that the scaffold exhibited sustained and stable NO release kinetics, as well as excellent near-infrared controllability. Immunofluorescence staining showed that the released NO upregulated the expression of neuronal markers Nestin and GFAP, indicating that the stem cells differentiated into neurons. Further mechanism revealed that the upregulated marker expression might be attributed to the enhanced Ca2+ influx. Consequently, this work might provide a novel perspective for nerve repair.

Recent Advances in Synergistic Effect of Nanoparticles and Its Biomedical Application

The synergistic impact of nanomaterials is critical for novel intracellular and/or subcellular drug delivery systems of minimal toxicity. This synergism results in a fundamental bio/nano interface interaction, which is discussed in terms of nanoparticle translocation, outer wrapping, embedding, and interior cellular attachment. The morphology, size, surface area, ligand chemistry and charge of nanoparticles all play a role in translocation. In this review, we suggest a generalized mechanism to characterize the bio/nano interface, as we discuss the synergistic interaction between nanoparticles and cells, tissues, and other biological systems. Novel perceptions are reviewed regarding the ability of nanoparticles to improve hybrid nanocarriers with homogeneous structures to enhance multifunctional biomedical applications, such as bioimaging, tissue engineering, immunotherapy, and phototherapy.