Bathochromic shift of the fluorescence spectral maximum with increasing generation of dansyl labeled Newkome type dendrimers

Dansyl moiety attached to the core of Newkome-type dendrimers shows a bathochromic shift of the fluorescence emission spectrum with increase in dendrimer generation. However the ET(30) plots in different solvents show a decrease in slope with increasing generation. This has been explained in terms of modification of transition energies and progressive shielding of the fluorophore with increasing generation

Self-association of protected Newkome-type second-generation dendrimers at nanomolar level concentrations in aqueous solution

Protected Newkome-type second-generation dendrimers (based on Lin's amine) were synthesized with a pyrene moiety attached to the core. The photophysical property in aqueous solution of the protected dendrimers shows self-association behavior in water. Pyrene excimer emission at 475 nm is observed in water even at very low concentrations of protected dendrimer (ca. 5 × 10-8 M). This emission band is absent in other solvents even up to a concentration of 10-5 M. The corresponding unprotected dendrimer does not show the pyrene excimer fluorescence. The amide of pyrene butyric acid with tert-butylamine shows the formation of excimer, albeit with very low intensity. Quenching studies on the dendrimer with hydrophilic quencher iodide anion (I-) reveal that there is significant quenching of fluorescence intensity in the case of N-tert-butyl-4-pyren-1-ylbutyramide as compared to that of the pyrene-attached second-generation protected dendrimer. This shows that the pyrene moiety in the case of the protected dendrimer is significantly shielded from the surrounding

Therapeutic Efficacy of Moxifloxacin Mucoadhesive Hydrogel for Bacterial Keratitis

Bacterial keratitis is a hypothetically devastating corneal infection due to the opportunity of fast development; corneal devastation either to be completed in 24–48 hours with even more contagious bacterial aetiological agents. Moxifloxacin mucoadhesive Hydrogel was prepared by using polymer Hydroxy Propyl Methyl Cellulose E50 LV by hydration method. Moxifloxacin was dissolved in small quantity of water and Benzalkonium Chloride was added to the Polymer solution. The formulations were evaluated for clarity, pH measurement, spread-ability test, drug content estimation, viscosity study, in vitro diffusion study and antibacterial activity. The developed formulation exhibits the sustained release over a period of 10 hour. The optimized formulation was further evaluated with antimicrobial activity. The results of the in-vitro antimicrobial activity of hydrogel were satisfactory. Keywords: Corneal Infection, Hydrogel, Moxifloxacin, invitro releas