Nanoparticles based on the zwitterionic pillar[5]arene and Ag+: synthesis, self-assembly and cytotoxicity in the human lung cancer cell line A549

A supramolecular electrochemical probe based on a tetrazole derivative pillar[5]arene/methylene blue system

For the first time, an original synthetic approach has been developed that enables the introduce ten tetrazole fragments into the pillar[5]arene structure. A supramolecular electrochemical probe was assembled for the first time from the obtained macrocycles and an electrochemically active signal converter: methylene blue (MB) dye. The ability of pillar[5]arene containing tetrazole fragments to selectively bind MB was confirmed by UV-vis and 2D 1H-1H NOESY spectroscopy. The stoichiometry of the resulting pillar[5]arene/MB complex = 1 : 2. This new supramolecular probe pillar[5]arene/MB allowed the detection of changes in the electrochemical signals of MB implemented in the supramolecular complex depending on the presence or absence of some metal ions (Zn2+ and Co2+) that do not exert their own redox activity. This will find further applications for the enhancement of the range of analytes detected by their influence on host-guest complexation and for the design of biosensors based on specific DNA-MB interactions.

Antibacterial Activity of Various Morphologies of Films Based on Guanidine Derivatives of Pillar[5]arene: Influence of the Nature of One Substitute on Self-assembly

The progress of the pillar[5]arene chemistry allowed us to set out a new concept on application of the supramolecular assemblies to create antimicrobial films with variable surface morphologies and biological activities. Antibacterial films were derived from the substituted pillar[5]arenes containing nine pharmacophoric guanidine fragments and one thioalkyl substituent. Changing the only thioalkyl fragment in the macrocycle structure made it possible to control the biological activity of the resulting antibacterial coating. Pretreatment of the surface with aqueous solution of the amphiphilic pillar[5]arenes reduced the biofilm thickness by 56 ± 10% of Gram-positive Staphylococcus aureus in the case of the pillar[5]arene containing a thiooctyl fragment and by 52 ± 7% for the biofilm of Gram-negative Klebsiella pneumoniae in the case of pillar[5]arene containing a thiooctadecyl fragment. Meanwhile, the cytotoxicity of the synthesized macrocycles was examined at a concentration of 50 μg/mL, which was significantly lower than that of bis-guanidine-based antimicrobial preparations.

Water-soluble Pillar[5]arene-based drug candidates for lung and breast cancer

The objective of research was to examine the likely anticancer effectiveness of distinct pillar[5] arene derivatives, ws-penta-P[5] and ws-deca-P[5], on breast and lung cancer cell lines in vitro. To achieve this goal, breast cancer (MCF7) cells, lung cancer (A549) cells, healthy cells (HEK293) were utilized. The IC50 dose of ws-penta-P[5] and ws-deca-P[5] was determined using the MTT method. Both treatment (pillar[5] arene applied) and control (pillar[5] arene not applied) groups were established for all three cell lines. Real-time polymerase chain reaction (qPCR) was used to evaluate changes in gene expression following pillar[5] arene treatment. Flow cytometry analysis was used to determine apoptosis and cell cycle arrest. The treatment group and control group results were compared after the study. The results revealed that in both cell lines treated with ws-deca-P[5], proapoptotic gene expressions were upregulated, while antiapoptotic gene expressions and caspase activation gene expressions were down-regulated. The flow cytometry apoptosis and cell cycle analysis in treatment group compared to the control, it was observed that the apoptosis rate increased in the ws-deca-P[5] and ws-deca-P[5] were shown to cause G0/G1 phase arrest in both cell groups. Results from our study that pillar[5] arene derivatives had the potential for treating breast and lung cancer, and more research is required in this area.Communicated by Ramaswamy H. Sarma.

Injectable Antibacterial Hydrogel with Asiaticoside-Loaded Liposomes and Ultrafine Silver Nanosilver Particles Promotes Healing of Burn-Infected Wounds

Post-injury infection and wound healing are recurrent daily life problems. Therefore, the necessity of developing a biomaterial with antibacterial and wound-healing properties is paramount. Based on the special porous structure of hydrogel, this work modifies recombinant collagen and quaternary ammonium chitosan and fused them with silver nanoparticles (Ag@mental-organic framework (Ag@MOF)) with antibacterial properties, and asiaticoside-loaded liposomes (Lip@AS) with anti-inflammatory/vascularization effects to form the rColMA/QCSG/LIP@AS/Ag@MOF (RQLAg) hydrogel. The prepared hydrogel possesses good sustainable release capabilities of Ag+ and AS and exhibits concentration-dependent swelling properties, pore size, and compressive strength. Cellular experiments show that the hydrogel exhibits good cell compatibility and promote cell migration, angiogenesis, and M1 macrophage polarization. Additionally, the hydrogels exhibit excellent antibacterial activity against Escherichia coli and Staphylococcus aureus in vitro. In vivo, Sprague Dawley rats burn-wound infection model showed that the RQLAg hydrogel could efficiently promote wound healing and has stronger healing promoting abilities than those of Aquacel Ag. In summary, the RQLAg hydrogel is expected to be an excellent material for accelerating open wound healing and preventing bacterial infections.

Novel Carboxylic Acid-Capped Silver Nanoparticles as Antimicrobial and Colorimetric Sensing Agents

The present work reports the synthesis, characterization, and antimicrobial activities of adipic acid-capped silver nanoparticles (AgNPs@AA) and their utilization for selective detection of Hg²⁺ ions in an aqueous solution. The AgNPs were synthesized by the reduction of Ag⁺ ions with NaBH₄ followed by capping with adipic acid. Characterization of as-synthesized AgNPs@AA was carried out by different techniques, including UV–Visible spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), X-ray diffraction (XRD), Dynamic Light Scattering (DLS), and zeta potential (ZP). In the UV–Vis absorption spectrum, the characteristic absorption band for AgNPs was observed at 404 nm. The hydrodynamic size of as-synthesized AgNPs was found to be 30 ± 5.0 nm. ZP values (−35.5 ± 2.4 mV) showed that NPs possessed a negative charge due to carboxylate ions and were electrostatically stabilized. The AgNPs show potential antimicrobial activity against clinically isolated pathogens. These AgNPs were found to be selectively interacting with Hg²⁺ in an aqueous solution at various concentrations. A calibration curve was constructed by plotting concentration as abscissa and absorbance ratio (A_Control − A_Hg/A_Control) as ordinate. The linear range and limit of detection (LOD) of Hg²⁺ were 0.6–1.6 μM and 0.12 μM, respectively. A rapid response time of 4 min was found for the detection of Hg²⁺ by the nano-probe. The effect of pH and temperature on the detection of Hg²⁺ was also investigated. The nano-probe was successfully applied for the detection of Hg²⁺ from tap and river water

Phyto-Fabrication of Silver Nanoparticles Using Typha azerbaijanensis Aerial Part and Root Extracts

BACKGROUND

Silver nanoparticles (AgNPs) were phyto-synthesized using Typha azerbaijanensis aerial part and root extracts, and their biological activities were investigated.

METHODS

This study was conducted in the Science and Research Branch, Islamic Azad University, Tehran, Iran in 2019. In this experimental study, silver nanoparticles (AgNPs) were phyto-synthesized and the physicochemical properties of AgNPs were determined using UV-Vis (UV-Vis) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) spectroscopy. Antibacterial and anticancer activity of synthesized AgNPs was determined using microdilution assay, and MTT 3- (4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) methods, respectively. The apoptotic effects of AgNPs were investigated using Real-Time PCR and flow cytometry techniques.

RESULTS

Morphological analysis of the synthesized AgNPs confirmed the spherical shape of AgNPs with an average size of 10.67 to 16.69 nm. The FTIR spectrum confirmed the presence of phytochemicals from T. azerbayenensis extract at the AgNP surface. Antibacterial experiments showed that phyto-fabricated AgNPs had significant antibacterial activity against Gram-negative bacteria. The AgNPs were significantly cytotoxic against breast cancer cell line (MCF-7) through induction of apoptosis.

CONCLUSION

The phyto-synthesized AgNPs had biological activities could be useful in pharmaceutical applications.

Green Silver Nanoparticles Synthesized from Taverniera couneifolia Elicits Effective Anti-Diabetic Effect in Alloxan-Induced Diabetic Wistar Rats

Background: Using a variety of chemical compounds and biomolecules, researchers have been working on new antidiabetic drugs for many years. Anti-diabetic research is increasingly using nanomaterials because of their unique qualities, such as their tiny size, biocompatibility, and ability to penetrate cell membranes for drug delivery. Using extract of T. couneifolia coated with silver nanoparticles as a model for diabetes mellitus research was one of the goals of this work. Methods: Uv-Vis spectroscopy was used to measure the TAgNPs surface plasmon resonance. FTIR spectroscopy confirmed the attached functional groups, XRD analysis confirmed the size and crystallinity, scanning electron microscopy revealed that the majority of the particles were spherical, and EDX performed the elemental analysis. For 21 days, alloxan-induced diabetic Wistar rats (N = 25, n = 5/group) were administered 10 mg/kg body weight of photosynthesized AgNPs as a standard animal model, while those in the untreated normal control group C, received distilled water as a control, diabetics who were treated with 0.5 mg/kg of body weight of glibenclamide, 10 mg/kg of methanolic T. couneifolia extract, and diabetics who were given 10 mg/kg of body weight of synthetic AgNPs derived from T. couneifolia in the DAgNPs group. At the conclusion of the treatment, lipid, liver and kidney profiles were re-examined to determine whether or not the treatment had been effective (day 21). Oral glucose doses of 2 g/kg of body weight were administered to each group, and blood glucose levels were measured at various intervals (day 21). Fasting glucose levels were measured using a glucometer. Each animal's urine was tested for leukocytes, nitrites, and bilirubin using lab-made prepared assay kits. One-way ANOVA and Dunnett's test were used for statistical analysis. Results: The surface plasmon resonance effect was examined with UV-vis, it showed a sharp peak at 412 nm. X-ray diffraction measurements indicated that the produced nanoparticles were between 15 to 31.44 nm in size. Alloxan-induced diabetic rats were fed AgNPs derived from phytosynthesized AgNPs, compared to diabetic control rats, diabetic rats treated with AgNPs showed a considerable improvement in their dyslipidemia status. Over the course of the days, it also lowered blood glucose levels. A reduction in blood glucose levels, a rise in body weight, and significant improvements in the lipid, liver, and renal profiles were also seen. Conclusions: The present findings revealed that plant mediated silver nanoparticles significantly improved the alloxan induced diabetic changes in various treated rats and might be used for the treatment of diabetes.

Design of Micro- and Nanoparticles: Self-Assembly and Application

The modern world throws down an increasing number of challenges to humanity [...].

Water-soluble pillar[5]arene sulfo-derivatives self-assemble into biocompatible nanosystems to stabilize therapeutic proteins

Pillar[5]arenes containing sulfonate fragments have been shown to form supramolecular complexes with therapeutic proteins to facilitate targeted transport with an increased duration of action and enhanced bioavailability. Regioselective synthesis was used to obtain a water-soluble pillar[5]arene containing the fluorescent label FITC and nine sulfoethoxy fragments. The pillar[5]arene formed complexes with the therapeutic proteins binase, bleomycin, and lysozyme in a 1:2 ratio as demonstrated by UV-vis and fluorescence spectroscopy. The formation of stable spherical nanosized macrocycle/binase complexes with an average particle size of 200 nm was established by dynamic light scattering and transmission electron microscopy. Flow cytometry demonstrated the ability of macrocycle/binase complexes to penetrate into tumor cells where they exhibited significant cytotoxicity towards A549 cells at 10^-5-10^-6 M while maintaining the enzymatic activity of binase.

Green Synthesis of Silver Nanoparticles Using Diospyros malabarica Fruit Extract and Assessments of Their Antimicrobial, Anticancer and Catalytic Reduction of 4-Nitrophenol (4-NP)

The green synthesis of silver nanoparticles (AgNPs) has currently been gaining wide applications in the medical field of nanomedicine. Green synthesis is one of the most effective procedures for the production of AgNPs. The Diospyros malabarica tree grown throughout India has been reported to have antioxidant and various therapeutic applications. In the context of this, we have investigated the fruit of Diospyros malabarica for the potential of forming AgNPs and analyzed its antibacterial and anticancer activity. We have developed a rapid, single-step, cost-effective and eco-friendly method for the synthesis of AgNPs using Diospyros malabarica aqueous fruit extract at room temperature. The AgNPs began to form just after the reaction was initiated. The formation and characterization of AgNPs were confirmed by UV-Vis spectrophotometry, XRD, FTIR, DLS, Zeta potential, FESEM, EDX, TEM and photoluminescence (PL) methods. The average size of AgNPs, in accordance with TEM results, was found to be 17.4 nm. The antibacterial activity of the silver nanoparticles against pathogenic microorganism strains of Staphylococcus aureus and Escherichia coli was confirmed by the well diffusion method and was found to inhibit the growth of the bacteria with an average zone of inhibition size of (8.4 ± 0.3 mm and 12.1 ± 0.5 mm) and (6.1 ± 0.7 mm and 13.1 ± 0.5 mm) at 500 and 1000 µg/mL concentrations of AgNPs, respectively. The anticancer effect of the AgNPs was confirmed by MTT assay using the U87-MG (human primary glioblastoma) cell line. The IC50 value was found to be 58.63 ± 5.74 μg/mL. The results showed that green synthesized AgNPs exhibited significant antimicrobial and anticancer potency. In addition, nitrophenols, which are regarded as priority pollutants by the United States Environmental Protection Agency (USEPA), can also be catalytically reduced to less toxic aminophenols by utilizing synthesized AgNPs. As a model reaction, AgNPs are employed as a catalyst in the reduction of 4-nitrophenol to 4-aminophenol, which is an intermediate for numerous analgesics and antipyretic drugs. Thus, the study is expected to help immensely in the pharmaceutical industries in developing antimicrobial drugs and/or as an anticancer drug, as well as in the cosmetic and food industries.

Metallo-Supramolecular Coordination Polymers Based on Amidopyridine Derivatives of Pillar[5]arene and Cu(II) and Pd(II) Cations: Synthesis and Recognition of Nitroaromatic Compounds

Decasubstituted pillar[5]arenes containing amidopyridine fragments have been synthesized for the first time. As was shown by UV-vis spectroscopy, the pillar[5]arenes with p-amidopyridine fragments form supramolecular associates with Cu(II) and Pd(II) cations in methanol in a 2:1 ratio. Using a sol-gel approach these associates are transformed into metallo-supramolecular coordination polymers (supramolecular gels) which were characterized as amorphous powders by scanning electron microscopy (SEM) and dynamic light scattering (DLS). The powders are able to selectively adsorb up to 46% of nitrophenols from water and were incorporated into an electrochemical sensor to selectively recognize them in aqueous acidic solution.

Thiacalixarene based quaternary ammonium salts as promising antibacterial agents

The search for new antibacterial and antiseptic drugs is an urgent problem due to the resistance of microorganisms to existing drugs. In this work, for the first time, the design of antibacterial and bactericidal agents based on quaternary ammonium compounds on thiacalixarene macrocyclic platform was proposed and implemented. A series of tetrasubstituted quaternary ammonium salts with different nature and length of the substituent (-N⁺(CH₃)₂R, R = CH₂Ph, C_nH_2n+1, n = 1, 4, 8, 10) based on p-tert-butylthiacalix[4]arene in cone and 1,3-alternate conformations was obtained with excellent yields. The obtained compounds have a high antibacterial effect against Gram-positive (S. aureus, S. epidermidis, B. subtilis) bacteria comparable with commercial antiseptics chlorhexidine, miramistin and benzalkonium chloride. It was found that quaternary ammonium derivatives of thiacalix[4]arene in 1,3-alternate conformation more effectively inhibit the growth of the tested bacterial strains in comparison with compounds in cone conformation. Cytotoxicity studies on human skin fibroblast (HSF) cells demonstrated that all compounds were less toxic compared to reference drugs. The different type of interaction of the studied compounds with model DPPC lipid membranes explains different antibacterial activity and cytotoxicity of compounds. The compounds in cone conformation are adsorbed on the DPPC vesicles membrane surface, while the incorporation of lipophilic alkyl fragments of macrocycles in 1,3-alternate conformation into the membrane leads to "clumping" of DPPC vesicles. It was shown the saving of antibacterial activity of thiacalixarene derivatives in 1,3-alternate conformation on Gram-positive clinical strains. The obtained results allow viewing the described thiacalixarene based quaternary ammonium compounds as promising molecules in the development of the new antibacterial agents.