Synthesis of Gold Nanoparticle: Peptide-Drug Conjugates for Targeted Drug Delivery.

Peptide-drug conjugates (PDCs) are being developed for the targeted delivery of drugs to cancer cells. Several approaches are being followed to enhance their stability in biological solutions. Here we describe an effective method to easily couple PDCs to polyethylene-coated gold nanoparticles. We also outline analytical methods to validate the coupling and assays to measure the stability and cytotoxic efficacy of the conjugates.

An insight study on HPTLC fingerprinting of Mukia maderaspatna: Mechanism of bioactive constituents in metal nanoparticle synthesis and its activity against human pathogens.

The present work reports the development of a Simple, rapid and eco-friendly route for the biosynthesis of gold and silver nanoparticles and their antimicrobial activity against gram positive and gram negative bacterial pathogens in the wound infected area. The synthesis was done using Mukia maderasapatna plant extract as a reducing agent. FT-IR analysis reported that the methanol extract was found to contain maximum number of functional groups which is responsible for the reduction of metal ions to metal nanoparticles. Further, the presence of bioactive molecules present in the methanol extract was confirmed by GC-MS analysis. The major phytochemical constituents observed in this Mukia maderaspatna leaf extract were n-hexadecanoic acid (15.51%), Octadecanoic acid (11.92%), stigmasterol (9.12%), Octadecanoic acid, 2, 3 hydroxypropyl ester (8.7%), Bicycloheptane, 2,6,6- trimethyl (5.57%) and stearic acid (4.23%). Initially, the formation of gold and silver nanoparticles was confirmed from their absorption spectra at 535 nm and 434 nm using UV- visible spectroscopy. The crystalline nature of the obtained gold and silver nanoparticles was confirmed by X-ray diffraction analysis. The average size of the gold and silver nanoparticles found around 50 nm and 20 nm respectively was confirmed by TEM analysis. The antimicrobial activities of silver and gold nanoparticles were checked against bacterial strains and the fungal strains. The formation of inhibition zones concluded that both the nanoparticles showed efficient antimicrobial activity against both the pathogens. Further, different concentrations of gold and silver nanoparticles, the antibiotics Ciprofloxacin and chloramphenicol as the positive control were carried out. The results concluded that the silver nanoparticles showed efficient activity against bacterial pathogens and fungal pathogens with the lowest concentration of 0.35 µg/ml and 0.45 µg/ml respectively.

Optimization of media composition for Nattokinase production by Bacillus subtilis using response surface methodology.

Response surface methodology and central composite rotary design (CCRD) was employed to optimize a fermentation medium for the production of Nattokinase by Bacillus subtilis at pH 7.5. The four variables involved in this study were Glucose, Peptone, CaCl2, and MgSO4. The statistical analysis of the results showed that, in the range studied; only peptone had a significant effect on Nattokinase production. The optimized medium containing (%) Glucose: 1, Peptone: 5.5, MgSO4: 0.2 and CaCl2: 0.5 resulted in 2-fold increased level of Nattokinase (3194.25U/ml) production compared to initial level (1599.09U/ml) after 10h of fermentation. Nattokinase production was checked with fibrinolytic activity.