Time filter

Source Type

Shavi G.V.,Manipal University India | Shavi G.V.,Waterford Institute of Technology | Nayak U.Y.,Manipal University India | Maliyakkal N.,Manipal University India | And 7 more authors.
Life Sciences | Year: 2015

Aim Formulation and evaluation of anastrozole, an anti-cancer drug loaded in different biodegradable polymeric nanoparticles. Materials and methods Different carrier systems such as poly(lactide-co-glycolide) (PLGA 50:50), poly(lactic-acid) (PLA) and poly(ε-caprolactone) (PCL) are used to prepare nanoparticles by simple emulsion technique. The surfactants polyvinyl alcohol and sodium deoxycholate were studied for their use as stabilizing agents at varying concentrations. The formulations were studied for their particle size, zeta potential, entrapment efficiency and solid state characteristics, and also were tested for their in vitro cytotoxicity and in vivo behavior in rats. Key findings The entrapment ranged from 35 to 85%, depending on the drug-polymer ratio used. Particle size ranged from 100 to 350 nm with optimal zeta potential. Accordingly, discrete spherical nanoparticles with smooth surface were obtained as evidence from Field Emission Scanning Electron Microscopy (FESEM) study. The solid state characteristics revealed dispersion of drug at the molecular level in the polymeric matrix of nanoparticles. A non-Fickian transport with initial burst release followed by slow release was observed with nanoparticles. The remarkable decrease in cell viability at various time points was observed for PLGA nanoparticles compared to other polymer matrices. The AUC(0 → ∞) of PLGA, PLA and PCL nanoparticles were found to be 4.77, 19.31 and 19.81 fold higher than (p < 0.05) anastrozole in solution, respectively. Also, pharmacokinetics study revealed the long time circulation of anastrozole loaded polymeric nanoparticles. Significance The results suggest that developed nanoparticles could be used successfully for effective management of breast cancer chemotherapy. © 2015 Elsevier Inc. Source

Behl G.,Pharmaceutical and Molecular Biotechnology Research Center | Iqbal J.,Pharmaceutical and Molecular Biotechnology Research Center | O'Reilly N.J.,Pharmaceutical and Molecular Biotechnology Research Center | McLoughlin P.,Pharmaceutical and Molecular Biotechnology Research Center | Fitzhenry L.,Pharmaceutical and Molecular Biotechnology Research Center
Pharmaceutical Research | Year: 2016

Purpose: Dexamethasone sodium phosphate (DXP) is an anti-inflammatory drug commonly used to treat acute and chronic ocular diseases. It is routinely delivered using eye-drops, where typically only 5% of the drug penetrates the corneal epithelium. The bioavailability of such ophthalmic drugs can be enhanced significantly using contact lenses incorporating drug-loaded nanoparticles (NPs). Methods: The mechanism of release from chitosan NPs (CS-NPs), synthesized by ionic gelation, was studied in vitro. The DXP loaded CS-NPs were subsequently entrapped in contact lenses and the optical and drug-release properties were assessed. Results: DXP release from CS-NPs followed diffusion and swelling controlled mechanisms, with an additional proposed impact from the electrostatic interaction between the drug and the CS-NPs. The release rate was found to increase with an increase in drug loading from 20 to 50 wt%. However, an inverse effect was observed when initial loading increased to 100 wt%. NP-laden lenses were optically clear (95–98% transmittance relative to the neat contact lens) and demonstrated sustained DXP release, with approximately 55.73% released in 22 days. Conclusions: The release profile indicated that drug levels were within the therapeutic requirement for anti-inflammatory use. These results suggest that these materials might be a promising candidate for the delivery of DXP and other important ophthalmic therapeutics. © 2016 Springer Science+Business Media New York Source

Coady T.M.,Pharmaceutical and Molecular Biotechnology Research Center | Coffey L.V.,Pharmaceutical and Molecular Biotechnology Research Center | O'Reilly C.,Pharmaceutical and Molecular Biotechnology Research Center | Owens E.B.,Pharmaceutical and Molecular Biotechnology Research Center | Lennon C.M.,Pharmaceutical and Molecular Biotechnology Research Center
Journal of Molecular Catalysis B: Enzymatic | Year: 2013

Nitrile hydrolysing enzymes have found wide use in the pharmaceutical industry for the production of fine chemicals. This work presents a strategy that facilitates the rapid identification of bacterial isolates demonstrating nitrile hydrolysing activity. The strategy incorporates toxicity, starvation and induction studies along with subsequent colorimetric screening for activity, further focusing the assessment towards the substrates of interest. This high-throughput strategy uses a 96 well plate system, and has enabled the rapid biocatalytic screening of 256 novel bacterial isolates towards β-hydroxynitriles. Results demonstrate the strategy's potential to rapidly assess a variety of β-hydroxynitriles including aliphatic, aromatic and dinitriles. A whole cell catalyst Rhodococcus erythropolis SET1 was identified and found to catalyse the hydrolysis of 3-hydroxybutyronitrile with remarkably high enantioselectivity under mild conditions, to afford (S)-3-hydroxybutyric acid in 42% yield and >99.9% ee. The biocatalytic capability of this strain including the variation of parameters such as temperature and time were further investigated and all results indicate the presence of a highly enantioselective if not enantiospecific nitrilase enzyme within the microbial whole cell. © 2013 Elsevier B.V. All rights reserved. Source

Discover hidden collaborations