FORMULATION AND EVALUATION OF FLOATING ORAL IN SITU GEL OF DILTIAZEM HYDROCHLORIDE

Objective: The objective of the present study was to formulate and evaluate the floating in-situ gelling system of diltiazem hydrochloride.Methods: Sodium alginate based diltiazem hydrochloride floating in situ gelling systems were prepared by dissolving hydroxyl propyl methyl cellulose (HPMC) in 25% of water, to which calcium carbonate and diltiazem hydrochloride were added with stirring to form, a proper and a homogenous dispersion of diltiazem hydrochloride. Meanwhile, 30% of water was heated to 60 ËšC on a hot plate to dissolve sodium alginate and cooled to 40 ËšC. The resulting solution was added to HPMC solution and mixed well. To 5% of water at 60 ËšC, sodium methyl paraben was added and dissolved and cooled to 40 ËšC and was added to the above mixture and mixed well. The volume was adjusted finally to 100% with distilled water. Prepared formulae were evaluated for physicochemical properties, drug content, pH, in vitro gelling capacity, in vitro buoyancy, viscosity, water uptake and in vitro drug release.Results: Formulation variables such as type and concentration of viscosity enhancing polymer (sodium alginate) and HPMC affected the formulation viscosity, gelling properties, floating behavior, and in vitro drug release. Formulation F5 and F6 showed the floating time of 5 min and more than 20 h respectively. A significant decrease in the rate and extent of the drug release was observed with the increase in polymer concentration in in-situ gelling preparation. Formulation F4, F5, F6 were shown to have extended drug release until the end of 7 h.Conclusion: The prepared in situ gelling formulations of diltiazem hydrochloride could float in the gastric conditions and released the drug in a sustained manner. The present formulation was non-irritant, easy to administer along with good retention properties, better patient compliant and with greater efficacy of the drug

Potential of enzymatically hydorlysed seaweed products as cost-effective nutrient media for growth and lipid enhancement in the marine microalga Nannochloropsis salina

Enzymatically hydrolysed seaweed products (EHSPs) prepared from the red seaweed, Gracilaria corticata (EHSP-1) and brown seaweed, Stoechospermum marginatum (EHSP-2) contained abundant levels of macro, micro and trace elements necessary to fulfil the nutritional requirement of the microalga Nannochloropsis salina. EHSP-1 had higher levels of N, P, K and Fe in comparison with EHSP-2. The growth performance of N. salina suggests that EHSP-1 was more efficient than EHSP-2. The growth rate of N. salina in EHSP-1 was 1.07 times higher than the control whereas in EHSP-2 the growth rate was 0.58 times lower than the control. The maximum biomass concentration of N. salina was achieved in EHSP-1 and EHSP-2 were 0.37 and 0.21 g l-1 with a biomass productivity of 0.027 and 0.0152 g l-1 d-1 respectively. The results of biochemical analyses also suggest that protein, pigment and lipid yield of N. salina was positively stimulated by EHSP. The findings suggest that the best concentration of EHSP-1 and EHSP-2 to achieve maximum biomass and lipid production of the marine microalga N. salina were 8 and 4% respectively. EHSP-1 enhanced the biomass and lipid production without affecting the nutritional properties of N. salina suggesting its potential applicability in aquaculture, biofuel and other related industrial sectors

Zinc oxide nanoparticle-coated films: fabrication, characterization, and antibacterial properties

In this article, novel antibacterial PVC-based films coated with ZnO nanoparticles (NPs) were fabricated, characterized, and studied for their antibacterial properties. It was shown that the ZnO NPs were coated on the surface of the PVC films uniformly and that the coating process did not affect the size and shape of the NPs on the surface of PVC films. Films coated with concentrations of either 0.2 or 0.075 g/L of ZnO NPs exhibited antibacterial activity against both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria, but exhibited no antifungal activity against Aspergillus flavus and Penicillium citrinum. Smaller particles (100 nm) exhibited more potent antibacterial activity than larger particles (1000 nm). All ZnO-coated films maintained antibacterial activity after 30 days in water

Cleanup of industrial effluents containing heavy metals : a new opportunity of valorising the biomass produced by brewing industry

Heavy metal pollution is a matter of concern in industrialised countries. Contrary to organic pollutants, heavy metals are not metabolically degraded. This fact has two main consequences: its bioremediation requires another strategy and heavy metals can be indefinitely recycled. Yeast cells of Saccharomyces cerevisiae are produced at high amounts as a by-product of brewing industry constituting a cheap raw material. In the present work, the possibility of valorising this type of biomass in the bioremediation of real industrial effluents containing heavy metals is reviewed. Given the auto-aggregation capacity (flocculation) of brewing yeast cells, a fast and off-cost yeast separation is achieved after the treatment of metal-laden effluent, which reduces the costs associated with the process. This is a critical issue when we are looking for an effective, eco-friendly, and low-cost technology. The possibility of the bioremediation of industrial effluents linked with the selective recovery of metals, in a strategy of simultaneous minimisation of environmental hazard of industrial wastes with financial benefits from reselling or recycling the metals, is discussed