Nanotechnology, Science and Applications最新文献

Purpose: The study aimed to investigate in vitro anti-aging activities of 29 Dendrobium spp. and develop and characterize microemulsions (MEs) for topical application.

Methods: Antioxidant activity was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), H₂O₂ scavenging, and ferric reducing antioxidant power (FRAP) assays. The anti-collagenase (MMP-1 and MMP-2) and anti-elastase activities were also evaluated. Cytotoxicity and human intracellular reactive oxygen species (ROS) levels were determined using resazurin reduction and 2',7'-dichlorofluorescin diacetate (DCFDA) assays, respectively. D. kentrophyllum extract-loaded microemulsion (DKME) was then prepared and optimized. The stability of DKME was studied using a heating-cooling cycle.

Results: D. kentrophyllum appeared to be the best candidate anti-aging agent because of its antioxidant, anti-collagenase, and anti-elastase activities. The extract was safe for human skin cells at a concentration of 6.25-100 μg/mL. It also decreased the intracellular ROS-induced ultraviolet B (UVB) irradiation compared to that in the control. DKME comprising Tween 80:ethanol (5:1), water, and isononyl isononanoate showed a suitable appearance, droplet size, polydisperse index, zeta potential, pH, and viscosity. This formulation demonstrated desirable physical and chemical stability, with non-cytotoxic effects.

Conclusion: DKME is considered a promising anti-aging product. However, an in vivo study of this optimized formulation might be evaluated in further study for anti-aging purposes.

Background: This study investigated the effects of pure iron oxide nanoparticles (Fe₃O₄ NPs), citrate-stabilized iron oxide nanoparticles (Fe₃O₄CA NPs), and indole-3-acetic acid (IAA), applied at various time regimes, on the germination, growth, and ex vitro development of chrysanthemum synthetic seeds. The genetic and metabolic stability of the plants was also assessed.

Methods: Nodal segments of Chrysanthemum × morifolium /Ramat./ Hemsl. 'Richmond', with a single axillary bud, were encapsulated in 3% calcium alginate with the addition of IAA (1 mg·L^-1) and/or NPs (7.7 mg·L^-1). The synthetic seeds were cultured in vitro for 30 or 60 days on a water-agar medium and then transplanted to the greenhouse for further analyses.

Results: Results indicated that IAA and Fe₃O₄CA NPs applied singularly significantly enhanced germination rates (83.33-92.18%) compared with the IAA- and NP-free control (56.67-64.18%), regardless of treatment time. The simultaneous use of IAA and Fe₃O₄CA NPs promoted longer shoot development after 30 days of treatment but showed negative effects after extended exposure. The same combination improved rooting efficiency compared to IAA alone. Supplementation with NPs improved acclimatization rates for younger plants but had variable effects on older plants. Leaf growth metrics were enhanced with Fe₃O₄CA NPs in plants after 30 days of treatment, yet no significant differences were observed in leaf dimensions after 60 days. The content of flavonoids, anthocyanins, and chlorophyll was affected by the exposure duration. Biochemical analyses revealed increased total polyphenol content and antioxidant capacity (FRAP, ABTS) in treated plants, particularly with IAA and Fe₃O₄CA NPs. Start codon targeted (SCoT) analyses showed no polymorphisms among treated plants, confirming their genetic stability.

Conclusion: The study found that the combination of IAA and Fe₃O₄CA NPs improved germination and shoot development in chrysanthemum synthetic seeds, while maintaining genetic stability, although prolonged exposure negatively affected plant growth metrics.

Introduction: Natural polymers have emerged as versatile and sustainable alternatives to synthetic polymers in pharmaceutical and biomedical applications. This study focuses on the extraction of arabinoxylan (AX) from maize husk and its potential as a promising excipient to enhance the solubility and oral bioavailability of Aripiprazole (APZ), a poorly water-soluble antipsychotic drug, offering a robust strategy for overcoming challenges associated with hydrophobic drugs.

Methods: APZ-loaded AX nanoparticles were synthesized using the ionotropic gelation technique. The formulation with the highest encapsulation efficiency designated as FN4 was selected for detailed characterization. Various analytical techniques, including Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), and Differential Scanning Calorimetry (DSC), were employed to assess the morphological, crystalline, and thermal properties of the nanoparticles. In vitro release studies were conducted on both simulated gastric fluid (pH 1.2) and simulated intestinal fluid (pH 6.8) to evaluate drug dissolution behaviour. The everted sac method was utilized to assess the permeation and transport of APZ from the AX-based nanoparticles.

Results: The FN4 formulation exhibited an encapsulation efficiency of 88.9% ± 1.77%, with a particle size of 284.4 nm, a polydispersity index (PDI) of 0.346, and a zeta potential of 20.7 mV. SEM analysis revealed a uniform distribution of polyhedral-shaped nanoparticles. XRD and DSC analyses indicated that APZ was in an amorphous state within the nanoparticles. Drug release was more pronounced at pH 6.8, with the AX nanoparticles showing sustained release. The everted sac method demonstrated enhanced permeation of APZ across intestinal membranes, supporting the potential of AX nanoparticles in improving drug absorption.

Discussion: The AX-based nanoparticle formulation significantly improved the solubility, pH-dependent release profile, and sustained release of APZ, offering a promising strategy to enhance the oral bioavailability of poorly soluble drugs. These findings suggest that AX nanoparticles could serve as an effective delivery system for enhancing the therapeutic potential of hydrophobic drugs like APZ.

Introduction: Nanotechnology is the science that deals with matter on the nanoscale, with sizes ranging from 1 to 100 nm. It involves designing, synthesising, characterising and applying these nanoscale materials. Nanoparticles (NPs) are known for their high surface-area to volume-ratio, surface charge density, low melting point, and distinguishably good optical/electrical properties. NPs exhibit an excellent drug delivery system, an effective contrast agent for vascular imaging, and effective antimicrobial activity. The biological synthesis of NPs is a simple, cost-effective, and environmentally friendly technique. This bottom-up technique utilises organisms' enzymes/bio-compounds and a plant extract as capping and reducing agents. Cinnamomum species are known for their intrinsic antimicrobial, antidiabetic, antioxidant, anti-inflammatory, anticancer, and neuroprotective properties. This review summarises articles that greenly synthesised NPs using Cinnamomum species' extracts, describing their methodologies, characterisation of the nanoparticles and their medical applications.

Methods: A literature search has been conducted on databases PubMed, ScienceDirect, and Frontier on the green synthesis of metal nanoparticles (MNPs) using Cinnamomum-based extracts. Various articles reported the methodology of utilising Cinnamomum species' extracts as reducing and capping agents. Only original lab articles were considered.

Results: Various types of MNPs have been successfully synthesised. The most common Cinnamomum species utilised as extracts is Cinnamomum tamala. The most common applications tested were the MNPs' antibacterial, antiviral, antifungal, antidiabetic and anticancerous activity. MNPs also had a role in treating mice-induced polycystic ovarian syndrome and Parkinson-like neurodegenerative diseases.

Conclusion: Cinnamomum species have been successfully utilised in the green synthesis of various MNPs. Silver and Gold NPs were the most reported. These MNPs proved their efficacy in multiple fields of medicine and biology, especially their antibacterial, antiviral and antifungal activity. Notably, the newly synthesised NPs showed promising results in treating polycystic ovarian syndrome in rats.

Introduction: Immobilizing enzymes on solid supports such as magnetic nanoparticles offers multi-dimensional advantages, including enhanced conformational, structural, and thermal stability for long-term storage and reusability.

Methodology: The gene encoding subtilisin Carlsberg was isolated from proteolytic Bacillus haynesii, a bacterium derived from salt mines. The nucleotide sequence encoding pro-peptide and mature protein were cloned into pET22(a)+ vector and expressed in E. coli. The extracted enzyme was subsequently immobilized on glutaraldehyde-linked-chitosan-coated magnetic nanoparticles.

Results: Fourier-transform infrared analysis revealed higher intensity peaks for the enzyme-immobilized nanoparticles indicating an increase in bonding numbers. X-ray diffraction analysis revealed a mild amorphous state for immobilized nanoparticles in contrast to a more crystalline state for free nanoparticles. An increased mass content and atomic percentage for carbon and nitrogen were recorded in EDX analysis for enzyme immobilized magnetic nanoparticles. Dynamic light scattering analysis showed an increase in average particle size from ~85 nm to ~250 nm. Upon enzyme immobilization, the Michaelis-Menten value increased from 11.5 mm to 15.02 mM, while the maximum velocity increased from 13 mm/min to 22.7 mm/min. Immobilization significantly improved the thermostability with 75% activity retained by immobilized enzyme at 70 °C compared to 50% activity by free enzyme at the same temperature. Immobilization yield, efficiency and activity recovery were 61%, 84% and 51%, respectively. The immobilized enzyme retained 70% of its activity after 10 cycles of reuse, and it maintained 55% of its activity compared to 50% activity by free enzyme after 30 days of storage.

Conclusion: The present study highlights the efficacy of magnetic nanoparticle-based immobilization in enhancing enzyme functioning and facilitates its incorporation into commercial applications necessitating high stability and reusability, including detergents, medicines, and bioremediation.

Purpose: As bacterial resistance to antibiotics increases, there is an urgent need to identify alternative antibacterial agents and improve antibacterial materials. One is the controlled transport of antibacterial agents that prevents infection with drug-resistant bacteria, especially in the treatment of difficult-to-heal wounds.

Methods: This work presents the use of electrospun PLCL/PVP (poly(L-lactide-co-ε-caprolactone/polyvinylpyrrolidone) nanofibers modified with two agents with antibacterial properties but with different mechanisms of action, that is, dendritic silver nanoparticles (Dend-AgNPs) and endolysin.

Results: The nanomat prepared in this manner showed significant antibacterial activity against antibiotic-resistant Pseudomonas aeruginosa strains, inhibiting their growth and production of key pigments and virulence factors. Moreover, the use of nanofibers as carriers of the selected factors significantly reduced their cytotoxicity towards human fibroblasts.

Conclusion: The results confirmed the possibility of using the presented product as an innovative dressing material, opening new perspectives for the treatment of wounds and combating bacterial infections with drug-resistant bacteria.

Purpose: Studying the role of nanoparticles in plant cryopreservation is essential for developing innovative methods to conserve plant genetic resources amid environmental challenges. This research investigated the effects of gold (AuNPs), silver (AgNPs), and zinc oxide (ZnONPs) nanoparticles on the structural integrity, genetic stability, and metabolic activity of cryopreserved plant materials with medicinal properties.

Methods: Shoot tips from two bleeding heart (Lamprocapnos spectabilis (L). Fukuhara) cultivars, 'Gold Heart' and 'Valentine', were cryopreserved using the encapsulation-vitrification technique, with nanoparticles added at concentrations of 5 or 15 ppm during either the preculture phase or the alginate bead matrix formation. Post-recovery, the plants underwent histological, molecular, and biochemical analyses.

Results: Electron microscopy observations of LN-derived plant material confirmed the production of micro-morpho-structurally stable cells. It was found that nanoparticles could penetrate the cell and accumulate in its various compartments, including the nucleus. As for the genetic analysis, SCoT markers identified polymorphisms in 11.5% of 'Gold Heart' plants, while RAPDs detected mutations in 1.9% of 'Valentine' specimens. Analysis of Molecular Variance (AMOVA) indicated that in the 'Valentine' cultivar, all genetic variation detected was within populations and not significantly affected by nanoparticle treatments. In 'Gold Heart', the majority (94%) of genetic variation detected was within populations, while 6% was attributed to nanoparticle treatments (mostly the application of 15 ppm ZnONPs). The application of nanoparticles significantly influenced the metabolic profile of bleeding heart plants, particularly affecting the synthesis of phenolic acids and aldehydes, as well as the antioxidant mechanisms in both 'Gold Heart' and 'Valentine' cultivars. The content of proteins was altered in 'Gold Heart' plants but not in 'Valentine'.

Conclusion: The results suggest that different types and concentrations of NPs have varying effects on the production of specific metabolites, which could be harnessed to modulate plant secondary metabolism for desired pharmacological outcomes.

Introduction: Trace elements such as manganese (Mn) are essential for various biological processes, including enzyme activation, metabolic pathways, and antioxidant defences. Given its involvement in these critical processes, maintaining adequate Mn levels is crucial for overall health.

Methods: The experimental design involved 24 male Wistar rats divided into three groups (n=8 per group): a control group receiving standard Mn supplementation (65 mg/kg), an Mn-deficient group, and a group supplemented with Mn₂O₃ nanoparticles (65 mg/kg). The 12-week feeding trial assessed selected physiological parameters, tissue composition, caecal health, and biochemical markers.

Results: Body and major organ weights were not significantly affected across groups (p=0.083 to p=0.579). However, significant differences were observed in fat tissue percentage (p=0.016) and lean tissue percentage (p<0.001). Caecal parameters showed higher ammonia levels (p=0.030) and increased pH (p=0.031) in the nano-Mn group. In turn, total SCFA concentrations were highest in the control group, followed by the Mn-deficient and nano-Mn groups (p<0.001). Enzymatic activities of caecal bacteria differed significantly between the groups, with reduced activity in the nano-Mn group (p<0.001). Blood plasma analysis revealed significantly lower insulin (p<0.001) and neurotransmitter levels, including dopamine and serotonin, in the Mn-deficient and nano-Mn groups compared to controls.

Discussion: Our findings suggest that both Mn supplementation and deficiency can lead to physiological and biochemical alterations, affecting fat metabolism, gut health and microbial enzymatic activity or neurotransmitter levels highlighting the critical role of Mn in maintaining metabolic homeostasis or its potential implications for nutritional and pharmaceutical interventions.