Green Facile Synthesis of Silver-Doped Zinc Oxide Nanoparticles and Evaluation of Their Effect on Drug Release

Comparative Analysis of Eugenol-Loaded Ag-Co and Unloaded Ag-Co Bimetallic Nanoparticles Against Escherichia coli

Recent developments in nanotechnology have revealed the significance of bimetallic nanoparticles for various applications. This study reveals the facile green synthesis of Ag-Co bimetallic nanoparticles using eugenol. A comparative analysis of Eugenol-loaded Ag-Co and unloaded Ag-Co bimetallic nanoparticle (BNPs) was done to investigate their antibacterial and antioxidant activity using flow cytometry. The biosynthesized Eugenol-loaded and unloaded BNPs were evaluated for antibacterial activity against Escherichia coli. The antioxidant activity was analyzed by using a DPPH scavenging activity assay and flow cytometry. UV-Vis spectroscopic analysis of synthesized eugenol-loaded and unloaded BNPs showed absorbance at 257 nm and 240 nm, respectively. FTIR analysis showed the peak range in the 500-4000 cm-1 corresponds to different functional groups. Zeta potential confirms the formation of stable and uniformly synthesized BNPs. EDX and SEM analysis confirm the elemental compositions and the size of the BNPs, respectively. Flow cytometric analysis revealed the live-dead parameters of Escherichia coli, when exposed to different concentrations of Eugenol-loaded Ag-Co (Eu@Ag-Co) and Unloaded Ag-Co BNPs. In addition, comparative MIC and MBC values of eugenol-loaded and unloaded BNPs were obtained for Escherichia coli. The Antioxidant activity revealed the comparative higher significant DPPH scavenging activity of Eu@Ag-Co. Moreover, the flow cytometric analysis confirmed the higher antibacterial efficacy of Eu@Ag-Co over unloaded Ag-Co BNPs by showing a higher percentage of dead cells. The study determined the enhanced antibacterial and antioxidant activity of nanoparticles by Eugenol loading and advocated it to be a better therapeutic approach. This study encourages the use of biosynthesized loaded-phytochemicals BNPs over unloaded BNPs.

Generation of Simulated "Natural" Nanoplastics from Polypropylene Food Packaging as the Experimental Standard

Current toxicology research on nanoplastics (NPs) generally uses commercial spherical NPs. However, the physicochemical characteristics of commercial NPs are significantly different from those of NPs formed under natural conditions, possibly affecting the validity of the results. In analytical chemistry, a reference sample is selected such that its physicochemical properties are as similar as possible to the target. Therefore, a simulated "natural" NP synthesized in the laboratory that closely resembles naturally derived NPs would be used as an authentic standard. Here, we established the assay of scanning electron microscope (SEM)-particle size distribution analyzer (PSDA)-surface-enhanced Raman scattering (SERS) to detect NPs and prepared simulated "natural" NPs from polypropylene food packaging material using a method that mimics natural conditions. Nanofiltration was used to isolate three sets of simulated NPs with particle sizes ranging from 50-100 nm, 100-200 nm, and 200-400 nm. These simulated "natural" NPs were more similar to naturally occurring counterparts when compared with commercial NPs. These new standard NPs, which should be scalable for large-scale use, will improve the accuracy, reliability, and translatability of toxicological studies of NPs.

Unravelling the Drug Encapsulation Ability of Functional DNA Origami Nanostructures: Current Understanding and Future Prospects on Targeted Drug Delivery

Rapid breakthroughs in nucleic acid nanotechnology have always driven the creation of nano-assemblies with programmable design, potent functionality, good biocompatibility, and remarkable biosafety during the last few decades. Researchers are constantly looking for more powerful techniques that provide enhanced accuracy with greater resolution. The self-assembly of rationally designed nanostructures is now possible because of bottom-up structural nucleic acid (DNA and RNA) nanotechnology, notably DNA origami. Because DNA origami nanostructures can be organized precisely with nanoscale accuracy, they serve as a solid foundation for the exact arrangement of other functional materials for use in a number of applications in structural biology, biophysics, renewable energy, photonics, electronics, medicine, etc. DNA origami facilitates the creation of next-generation drug vectors to help in the solving of the rising demand on disease detection and therapy, as well as other biomedicine-related strategies in the real world. These DNA nanostructures, generated using Watson-Crick base pairing, exhibit a wide variety of properties, including great adaptability, precise programmability, and exceptionally low cytotoxicity in vitro and in vivo. This paper summarizes the synthesis of DNA origami and the drug encapsulation ability of functionalized DNA origami nanostructures. Finally, the remaining obstacles and prospects for DNA origami nanostructures in biomedical sciences are also highlighted.

Synthesis, Characteristics, and Effect of Zinc Oxide and Silver Nanoparticles on the In Vitro Regeneration and Biochemical Profile of Chrysanthemum Adventitious Shoots

Studies on nanoparticles' effects on plants are relevant for horticulture. This study aimed to test the influence of zinc oxide submicron particles (ZnO SMPs), zinc oxide nanoparticles (ZnO NPs), and zinc oxide nanoparticles combined with silver nanoparticles (ZnO+1%Ag NPs) applied at 100 and 500 mg·L^-1 on the regeneration and biochemical activity of adventitious shoots in Chrysanthemum × morifolium (Ramat.) Hemsl. 'UTP Burgundy Gold' and 'UTP Pinky Gold'. The original microwave solvothermal synthesis and characteristics of the ZnO samples were described. Internodes were cultured on the MS medium with 0.6 mg∙L^-1 6-benzylaminopurine (BAP) and 2 mg∙L^-1 indole-3-acetic acid (IAA). In 'UTP Burgundy Gold', the highest shoot regeneration efficiency was obtained for 100 mg·L^-1 ZnO SMPs and 500 mg·L^-1 ZnO NPs treatments (6.50 and 10.33 shoots per explant, respectively). These shoots had high or moderate chlorophyll and carotenoid contents. In 'UTP Pinky Gold', the highest shoot number was produced in the control (12.92), for 500 mg·L^-1 ZnO SMPs (12.08) and 500 mg·L^-1 ZnO NPs (10.42). These shoots had increased chlorophyll (a+b)-to-carotenoid ratios. In 'UTP Pinky Gold', the ZnO SMPs and ZnO NPs affected the anthocyanins biosynthesis, whereas ZnO + 1%Ag NPs decreased the phenolics accumulation. These results are important for the improvement of chrysanthemum micropropagation.

Silver-Coated Silica Nanoparticles Modified with MPS: Potential Antimicrobial Biomaterials Applied in Glaze and Soft Reliner

Soft reliner and glaze are materials used over full or partial dental prosthesis to prevent excessive pressure on the supporting tissues. They are also indicated as supportive treatment for dental stomatitis, especially when modified by the addition of medications. The objective of the work was to evaluate the antimicrobial effect of silver-coated silica nanoparticles in a glaze and a soft reliner. The nanoparticles were synthesized, characterized, and tested by minimum inhibitory concentration (MIC) for C. albicans SC5314. Then, the nanoparticles were incorporated to a glaze and a soft reliner, which were called nanocomposites. Then, the nanocomposites were divided into six groups (n = 12): CG: glaze/reliner; CR: reliner; G1: glaze + 1% nanoparticles/reliner; G2: glaze + 2.5% nanoparticles/reliner; R1: reliner + 1%; R2: reliner + 2.5%. The nanocomposites were characterized by a goniometer and by a scanning electron microscope. The antibiofilm test was performed against C. albicans SC5314. According to the MIC results, the non-functionalized nanoparticles reduced fungal growth at 1000 μg/mL and the functionalized nanoparticles at 2000 μg/mL. The functionalized nanoparticle had a superior dispersion being selected for the antibiofilm test. There was a reduction of 64% in CFU/specimen count for the glaze, not statistically significant (p = 0.244). For the soft reliner, there was an increase in CFU/specimen with the presence of nanoparticles, still not statistically significant (p = 0.264). In conclusion, it is necessary to conduct new studies to increase the release of silver, thus improving nanoparticles' antifungal potential.