Enhanced pharmacological activity of vitamin B₁₂ and penicillin as nanoparticles

Antiviral activity of nano-monocaprin against Phi6 as a surrogate for SARS-CoV-2

The COVID-19 pandemic involving SARS-CoV-2 has raised interest in using antimicrobial lipid formulations to inhibit viral entry into their host cells or to inactivate them. Lipids are a part of the innate defense mechanism against pathogens. Here, we evaluated the use of nano-monocaprin (NMC) in inhibiting enveloped (phi6) and unenveloped (MS2) bacteriophages. NMC was prepared using the sonochemistry technique. Size and morphology analysis revealed the formation of ~ 8.4 ± 0.2-nm NMC as measured by dynamic light scattering. We compared the antiviral activity of NMC with molecular monocaprin (MMC) at 0.5 mM and 2 mM concentrations against phi6, which we used as a surrogate for SARS-CoV-2. The synthesized NMC exhibited 50% higher antiviral activity against phi6 than MMC at pH 7 using plaque assay. NMC inactivated phi6 stronger at pH 4 than at pH 7. To determine if NMC is toxic to mammalian cells, we used MTS assay to assess its IC₅₀ for HPDE and HeLa cell lines, which were ~ 203 and 221 µM, respectively. NMC may be used for prophylactic application either as a drop or spray since many viruses enter the human body through the mucosal lining of the nose, eyes, and lungs.

Crystal structure and Hirshfeld surface analysis of 2-(4-chloro-phen-yl)-4-(di-meth-oxy-meth-yl)-5-phenyl-1,3-thia-zole

In the title compound, C18H16ClNO2S, the thia-zole ring subtends dihedral angles of 13.12 (14) and 43.79 (14) ° with the attached chloro-phenyl and phenyl rings, respectively. In the crystal, C-H⋯π inter-actions link the mol-ecules, forming a three-dimensional network. The roles of the various inter-molecular inter-actions were clarified by Hirshfeld surface analysis, which reveals that the most important contributions to the crystal packing are from H⋯H (39.2%), H⋯C/C⋯H (25.2%), Cl⋯H/H⋯Cl (11.4%) and O⋯H/H⋯O (8.0%) contacts.

Nanoantibiotics: Functions and Properties at the Nanoscale to Combat Antibiotic Resistance

One primary mechanism for bacteria developing resistance is frequent exposure to antibiotics. Nanoantibiotics (nAbts) is one of the strategies being explored to counteract the surge of antibiotic resistant bacteria. nAbts are antibiotic molecules encapsulated with engineered nanoparticles (NPs) or artificially synthesized pure antibiotics with a size range of ≤100 nm in at least one dimension. NPs may restore drug efficacy because of their nanoscale functionalities. As carriers and delivery agents, nAbts can reach target sites inside a bacterium by crossing the cell membrane, interfering with cellular components, and damaging metabolic machinery. Nanoscale systems deliver antibiotics at enormous particle number concentrations. The unique size-, shape-, and composition-related properties of nAbts pose multiple simultaneous assaults on bacteria. Resistance of bacteria toward diverse nanoscale conjugates is considerably slower because NPs generate non-biological adverse effects. NPs physically break down bacteria and interfere with critical molecules used in bacterial processes. Genetic mutations from abiotic assault exerted by nAbts are less probable. This paper discusses how to exploit the fundamental physical and chemical properties of NPs to restore the efficacy of conventional antibiotics. We first described the concept of nAbts and explained their importance. We then summarized the critical physicochemical properties of nAbts that can be utilized in manufacturing and designing various nAbts types. nAbts epitomize a potential Trojan horse strategy to circumvent antibiotic resistance mechanisms. The availability of diverse types and multiple targets of nAbts is increasing due to advances in nanotechnology. Studying nanoscale functions and properties may provide an understanding in preventing future outbreaks caused by antibiotic resistance and in developing successful nAbts.

Strategies to prevent the occurrence of resistance against antibiotics by using advanced materials

Drug resistance occurrence is a global healthcare concern responsible for the increased morbidity and mortality in hospitals, time of hospitalisation and huge financial loss. The failure of the most antibiotics to kill "superbugs" poses the urgent need to develop innovative strategies aimed at not only controlling bacterial infection but also the spread of resistance. The prevention of pathogen host invasion by inhibiting bacterial virulence and biofilm formation, and the utilisation of bactericidal agents with different mode of action than classic antibiotics are the two most promising new alternative strategies to overcome antibiotic resistance. Based on these novel approaches, researchers are developing different advanced materials (nanoparticles, hydrogels and surface coatings) with novel antimicrobial properties. In this review, we summarise the recent advances in terms of engineered materials to prevent bacteria-resistant infections according to the antimicrobial strategies underlying their design.

Triterpenoid dan Nanopartikel Ekstrak n-Heksana dari Rimpang Lengkuas Merah (Alpinia purpurata (Vieill.) K. Schum) Serta Uji Sitotoksisitas dengan BSLT

Penelitian ini bertujuan untuk mengisolasi senyawa triterpenoid dari rimpang Alpinia purpurata dan fabrikasi nanopartikel ekstrak n-heksana serta membandingkan aktivitas sitotoksik antara nanopartikel dan ekstrak n-heksana. Senyawa triterpenoid diisolasi dari ekstrak n-heksana menggunakan kromatografi kolom gravitasi dan KLT Preparatif. Metode yang digunakan untuk fabrikasi ekstrak n-heksana menjadi nanopartikel adalah sonikasi dengan menggunakan prosesor ultrasonik. Penentuan aktivitas sitotoksik ekstrak n-heksana menggunakan metode BSLT (Brine Shrimp Lethality Test). Hasil analisis GC-MS isolat triterpenoid memiliki berat molekul sebesar 426 g/mol diduga merupakan senyawa Lupeol. Berdasarkan analisis ukuran partikel menggunakan instrumen PSA, nanopartikel ekstrak n-heksana memiliki ukuran 278,0 nm. Hasil uji sitotoksisitas ekstrak n-heksana dan nanopartikel ekstrak n-heksana menghasilkan LC50 berturut-turut sebesar 109,668 ppm dan 86,783 ppm. Ekstrak n-heksana dalam bentuk nanopartikel dapat meningkatkan bioaktivitas.

Morphology and Characteristics of Starch Nanoparticles Self-Assembled via a Rapid Ultrasonication Method for Peppermint Oil Encapsulation

Starch nanoparticles (SNPs) and peppermint oil (PO)-loaded SNPs were fabricated via an ultrasonic bottom-up approach using short linear glucan debranched from waxy maize starch. The effects of the glucan concentration, ultrasonic irradiation time, and chain length on the SNPs' characteristics were investigated. Under the optimal conditions, i.e., short linear glucan concentration of 5% and ultrasonication time of 8-10 min, SNPs were successfully prepared. The as-prepared SNPs showed good uniformity and an almost perfect spherical shape, with diameters of 150-200 nm. The PO-loaded SNPs also exhibited regular shapes, with sizes of approximately 200 nm. The loading capacity, encapsulation efficiency, and yield of PO-loaded SNPs were ∼25.5%, ∼87.7%, and ∼93.2%, respectively. After encapsulation, PO possessed enhanced stability against thermal treatment (80 °C). The pseudo-first-order kinetics model accurately described the slow-release properties of PO from SNPs. This new approach of fabricating SNPs is rapid, high yield, and nontoxic, showing great potential in the encapsulation and sustained release of labile essential oils or other lipids.

Imipenem/cilastatin encapsulated polymeric nanoparticles for destroying carbapenem-resistant bacterial isolates

Background

Carbapenem-resistance is an extremely growing medical threat in antibacterial therapy as the incurable resistant strains easily develop a multi-resistance action to other potent antimicrobial agents. Nonetheless, the protective delivery of current antibiotics using nano-carriers opens a tremendous approach in the antimicrobial therapy, allowing the nano-formulated antibiotics to beat these health threat pathogens. Herein, we encapsulated imipenem into biodegradable polymeric nanoparticles to destroy the imipenem-resistant bacteria and overcome the microbial adhesion and dissemination. Imipenem loaded poly Ɛ-caprolactone (PCL) and polylactide-co-glycolide (PLGA) nanocapsules were formulated using double emulsion evaporation method. The obtained nanocapsules were characterized for mean particle diameter, morphology, loading efficiency, and in vitro release. The in vitro antimicrobial and anti adhesion activities were evaluated against selected imipenem-resistant Klebsiella pneumoniae and Pseudomonas aeruginosa clinical isolates.

Results

The obtained results reveal that imipenem loaded PCL nano-formulation enhances the microbial susceptibility and antimicrobial activity of imipenem. The imipenem loaded PCL nanoparticles caused faster microbial killing within 2–3 h compared to the imipenem loaded PLGA and free drug. Successfully, PCL nanocapsules were able to protect imipenem from enzymatic degradation by resistant isolates and prevent the emergence of the resistant colonies, as it lowered the mutation prevention concentration of free imipenem by twofolds. Moreover, the imipenem loaded PCL eliminated bacterial attachment and the biofilm assembly of P. aeruginosa and K. pneumoniae planktonic bacteria by 74 and 78.4%, respectively.

Conclusions

These promising results indicate that polymeric nanoparticles recover the efficacy of imipenem and can be considered as a new paradigm shift against multidrug-resistant isolates in treating severe bacterial infections.