Poloxamer.

Tamoxifen Citrate (TC), an antiestrogenic drug, is used in both pre and post menopausal breast cancer treatment in women. One of the major causes of its poor bioavailability is attributed to its poor aqueous solubility. In this study an effort has been made to improve the aqueous solubility of the hydrophobic drug using methods like cosolvency and micellisation. Cosolvents (ethanol, polyethylene glycol-400), and surfactants [polyoxyethylene sorbitan monooleate (Tween-80), Poloxamer-407 and Poloxamer-188] were tested for their solubilizing potential. Solubility enhancement approaches showed variable degrees of increase in solubility of TC. Solubility studies with different concentrations of Ethanol and PEG-400 at 37°C showed that higher efficiency of increasing solubility by cosolvency was achieved with ethanol (6.10 fold) than that with PEG 400 (5.62 fold) while in case of varying concentrations of surfactants (tween 80, Poloxamer 188 and Poloxamer 407). Poloxamer 407 exhibited maximum potential in solubilizing TC in water (7.1 fold). However, among the solubilizing techniques and solubilizing agents used, micellization with polysorbate 80 as surfactant was found to be the most effective. Data suggests that using simple techniques, improvement of solubility of TC can be attained which may help in improving its poor bioavailability.

The objective of the present study was to prepare in situ hydrogel for controlled release of ofloxacin using various polymers such as Poloxamer P407, Sodium Alginate and Polyox. In situ were characterized for the Appearance, pH determination, In vitro Gelation studies and viscosity, Rheological studies, Drug Content, In vitro Drug release study, Sterility testing. Drug-excipient compatibility was determined by FTIR. Infrared spectroscopy studies of Ofloxacin, Polyox, Sodium alginate, Poloxamer and HPMC K4M alone and their physical mixture revealed that, Ofloxacin is compatible with all the polymers used. The clarity of the prepared formulations was found satisfactory. The pH of all formulations was found to be satisfactory in the range. The drug content of the prepared formulation was within the acceptable range, and ensures dose uniformity. The curve fitting data revealed that the release followed zero order kinetics.