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131.
M. A. Kalam A. Samad Asgar Ali M. Aqil M. Sharma 《Journal of Dispersion Science and Technology》2013,34(1):89-96
The conventional ophthalmic solutions have demonstrated poor bioavailability and low therapeutic response due to rapid precorneal elimination of drug, which could be overcome by the use of in situ gelling systems that are instilled as drops into the eye and undergo a sol‐gel transition in the cul‐de‐sac. The present work describes the formulation of an ophthalmic delivery system of an antibacterial agent, Gatifloxacin, based on the concept of ion‐activated in situ gelation; the rheological properties of the formulation and in vitro release of the drug were evaluated. Gelrite gellan gum, a novel vehicle for ophthalmic delivery system, which gels in the presence of mono/divalent cations present in the tear fluid, was used as the gelling agent. The developed formulation showed pseudoplastic rheology and was therapeutically efficacious and provides sustained release of the drug over a 12‐hour period. The developed system is thus a viable alternative to conventional eye drops. 相似文献
132.
Naser Montazeri Samad Khaksar Akbar Nazari Seyed Mohammad Vahdat 《Journal of fluorine chemistry》2011,132(7):450-5946
Pentafluorophenylammonium triflate (PFPAT) is used as an efficient catalyst in the von Pechmann condensation of phenols with β-ketoesters leading to the formation of coumarin derivatives. Short reaction times, easy and quick isolation of the products, excellent chemoselectivity, excellent yields and ease of catalyst recovery with consistent activity makes this protocol efficient and environmentally benign. 相似文献
133.
An efficient solvent free method for the synthesis of various 3,4-dihydropyrimidin-2(1H)-one/thiones in excellent yields using sulfonatedβ-cyclodextrine as recyclable catalyst is described.Sulfonatedβ-cyclodextrine was found to be efficient,recyclable heterogeneous catalyst and showed rate enhancements,high yields and short reaction times in this transformation. 相似文献
134.
We report here the observation, for the first time, of the enhancement of Europium-Tetracycline complex emission in cholesterol
solutions. This enhancement was initially observed with the addition of the enzyme cholesterol oxidase, which produces H2O2, the agent driver of the Europium tetracycline complex, to the solution. However, it was found that the enzyme is not needed
to enhance the luminescence. A calibration curve was determined, resulting in a simple method to measure the cholesterol quantity
in a solution. This method shows that the complex can be used as a sensor to determine cholesterol in biological systems. 相似文献