Floating Drug Delivery of Nevirapine as a Gastroretentive System

A multiple-unit floating drug delivery system based on gas formation technique was developed, in order to prolong the gastric residence time and to increase the overall bioavailability of the dosage form. The floating bead formulations were prepared by dispersing nevirapine together with calcium carbonate in a mixture of sodium alginate and hydroxypropyl methylcellulose solution and then dripping the dispersion into an acidified solution of calcium chloride. Calcium alginate beads were formed, as the alginate underwent ionotropic gelation by calcium ions, and carbon dioxide developed from the reaction of carbonate salts with acid. The obtained beads were able to float due to CO2-gas formation and the gas entrapment by the polymeric membrane. The prepared beads were evaluated for percent drug loading, drug entrapment efficiency, morphology, surface topography, buoyancy, in-vitro release, and release kinetics. The formulations were optimized for different weight ratios of the gas-forming agent and sodium alginate. The beads containing higher amounts of calcium carbonate demonstrated an instantaneous, complete, and excellent floating ability over a period of 24 hours. The increased amount of the gas forming agent did not affect the time to float, but increased the drug release from the floating beads, while increasing the coating level of the gas-entrapped membrane, increased the time to float, and slightly retarded the drug release. Good floating properties and sustained drug release were achieved. Finally, these floating beads seemed to be a promising gastroretentive drug delivery system

Iodine/Et<SUB>3</SUB>SiH: a novel reagent system for the synthesis of 3-aryl-1H-indenes from 1,3-diaryl propargyl alcohols

1,3-Diaryl propargyl alcohols undergo smooth intramolecular Friedel-Crafts cyclization with triethylsilane in the presence of 10 mol % iodine 3-aryl-1H-indene derivatives in good yields in short reaction times. This is the first example on the synthesis of substituted indenes from 1,3-diaryl propargyl alcohols. The use of inexpensive and readily available molecular iodine makes this method quite simple, more convenient, and practical

The IMPACT OF CLINICAL PHARMACY SERVICES IN GENERAL SURGERY

Objective: The objectives of this study include performing pharmaceutical care-related research and documenting regarding drug-related problems in the surgery department. Further, these types of studies may bring consciousness to both physicians and patients regarding drug use in surgery. Methods: A Prospective interventional study was conducted in a general surgery hospital. The prescriptions were analyzed for the use of inappropriateness of drugs using the classification for drug-related problems. Results: Out of 100 cases, 62 patients were observed with drug-related problems. The number of antibiotics prescribed was 0, 1, 2, 3, 4, 5, 6 in 8, 11, 12, 32, 18, 18, 1 cases respectively. A significant increase in the outcome of antibiotic rationality and cases adhered to guidelines was seen in November compared to October and somewhat decreased in December due to some limitations. The overall study states that prescribing has a more important cause of Drug-related problems compared to dispensing and the use of the drug. Conclusion: Drug-related problems have to be acknowledged as a very important contributing treatment factor for the best health care outcome. Our study shows the importance of clinical pharmacists in every hospital for identifying and resolving drug-related problems and medication errors

Modelling photovoltaic soiling losses through optical characterization

The accumulation of soiling on photovoltaic (PV) modules affects PV systems worldwide. Soiling consists of mineral dust, soot particles, aerosols, pollen, fungi and/or other contaminants that deposit on the surface of PV modules. Soiling absorbs, scatters, and reflects a fraction of the incoming sunlight, reducing the intensity that reaches the active part of the solar cell. Here, we report on the comparison of naturally accumulated soiling on coupons of PV glass soiled at seven locations worldwide. The spectral hemispherical transmittance was measured. It was found that natural soiling disproportionately impacts the blue and ultraviolet (UV) portions of the spectrum compared to the visible and infrared (IR). Also, the general shape of the transmittance spectra was similar at all the studied sites and could adequately be described by a modified form of the Ångström turbidity equation. In addition, the distribution of particles sizes was found to follow the IEST-STD-CC 1246E cleanliness standard. The fractional coverage of the glass surface by particles could be determined directly or indirectly and, as expected, has a linear correlation with the transmittance. It thus becomes feasible to estimate the optical consequences of the soiling of PV modules from the particle size distribution and the cleanliness value