Silver Is Not Equal to Silver: Synthesis and Evaluation of Silver Nanoparticles with Low Biological Activity, and Their Incorporation into C(12)Alanine-Based Hydrogel

Development and optimization of Clitoria teratea synthesized silver nanoparticles and its application to nanogel systems for wound healing

OBJECTIVE

The present research deals with sequential optimization strategy based on Central Composite Design to optimize the process variables for efficient production of Clitoria teratea (CLT) synthesized silver nanoparticles (AgNPs) using biological synthesis.

METHODS

Two substantial factors influencing the dependent variables viz UV-visible absorbance, particle size, zeta potential and polydispersity index (PDI) were identified as NaOH concentration, RH concentration, temperature as independent variables. In-vitro and ex-vivo studies of prepared CLT-AgNPs gel and marketed gel were carried out using dialysis membrane and egg membrane, respectively. In addition, antimicrobial study was also performed on the bacterial strains.

RESULTS

The particles size (114 nm), PDI (0.45), and zeta potential (-29.5 mV) of optimized formulation were found, respectively. In-vitro profile of AgNPs from prepared CLT-AgNPs gel was noted (95.6%) in 8 h. It was found that the prepared CLT-AgNPs gel stimulates fibroblast and agranulocytosis development resulting better and timely wound healing.

CONCLUSIONS

The prepared CLT-AgNPs gel can be as a potential substitute in the management and treatment of acute and chronic wounds.

Development and Optimization of Erythromycin Loaded Transethosomes Cinnamon Oil Based Emulgel for Antimicrobial Efficiency

Erythromycin (EM) is a macrolide antibiotic that is frequently used to treat skin bacterial infections. It has a short half-life (1-1.5 h), instability in stomach pH, and a low oral bioavailability. These foregoing factors limit its oral application; therefore, the development of topical formulations loaded with erythromycin is an essential point to maximize the drug's concentration at the skin. Accordingly, the current study's goal was to boost the antimicrobial activity of EM by utilizing the advantages of natural oils such as cinnamon oil. Erythromycin-loaded transethosomes (EM-TE) were generated and optimized using a Box-Behnken design employing, phospholipid concentration (A), surfactant concentration (B), and ethanol content (C) as independent variables. Their effects on entrapment efficiency, EE, (Y₁) and the total amount of erythromycin that penetrated the skin after 6 h, Q6h (Y₂), were assessed. The optimized transethosome showed a particle size of 256.2 nm, EE of 67.96 ± 0.59%, and Q6h of 665.96 ± 5.87 (µg/cm²) after 6 h. The TEM analysis revealed that, the vesicles are well-known packed structures with a spherical shape. The optimized transethosomes formulation was further transformed into a cinnamon oil-based emulgel system using HPMC as a gelling agent. The generated EM-TE-emulgel was characterized by its physical features, in vitro, ex vivo studies, and antimicrobial activities. The formulation showed sufficient characteristics for effective topical application, and demonstrated a great stability. Additionally, EM-TE-Emulgel had the highest transdermal flux (120.19 μg/cm²·h), and showed considerably (p < 0.05) greater antimicrobial activity, than EM-TE-gel and placebo TE-Emulgel. The action of EM was subsequently augmented with cinnamon oil, which eventually showed a notable effect against bacterial growth. Finally, these results demonstrate that the transethosomes-loaded cinnamon oil-based emulgel is an alternative way to deliver erythromycin for the treatment of topical bacterial infections.