Ethanol excipient

In an extension of this work, pellets of a blend of PCL and hy-droxypropylcellulose containing fluridone were prepared by grinding, blending, and then melt-spinning the mixture with a Berstorff twin screw extruder (78). The extruded rod was subsequently water-quenched and pelletized. Pellets were also prepared by coating bundles of extruded rods with the water-soluble excipients PEG 3350 and PEG 600 (95 5). In vitro release rate measurements were conducted in the simulant medium of 50% aqueous ethanol or hardened water. 

A commercial analgesic tablet is stated on the packet to contain 325 mg of aspirin and 50 mg of caffeine per tablet. Two tablets + 0.0773 g of phenacetin were shaken with 10 cm3 of ethanol for 10 minutes, then 10 cm3 of 0.5 mol dm 3 ammonium formate were added and the mixture made up to 100 cm3. The tablets contain insoluble excipients, so a little of the solution was filtered before chromatography --- ... 

A lowering of the permeability coefficients of compounds has been reported during the screening procedure using cell monolayers and commonly used excipients [98] (e.g., using PEG 400, DMSO), and it is also known that both DMSO and ethanol affect the general metabolic capacity of the cells, leading to an overestimation of permeability [156],... 

Selective differential UV spectrophotometric method was presented for the determination of niclosamide in bulk and in its pharmaceuticals [43]. The method was based on measuring niclosamide in alkaline solutions against their neutral ethanolic solutions as blanks. The proposed method was sensitive, highly specific, and advantageous over the conventional UV assays, since the interference of the excipients, impurities, degradation products, or other accompanying drugs was nullified. 

BMS-204352, a novel substituted 3-fluorooxindole, is a potassium channel opener being developed for the treatment of stroke. Nassar et al. [96] reported on the development of a non-aqueous parenteral formulation of BMS-204352. This formulation was composed of a mixture of PEG 300, polysorbate 80, ethanol and water. The authors reported on the formation of 1-hydroxymethyl adduct of BMS-204352 (formaldehyde adduct), which was linked with residual levels of formaldehyde in the polymeric excipients. 

Solution-based systems are common to both nebulizers and nasal formulations. In general, water will form the greatest fraction of the formulation, but, in some cases, cosolvents such as ethanol and propylene glycol may be added for increased stability. Acidifying and alkalizing excipients may also be added to optimize pH from the perspective of the drug stability as well as the physiological effect on the airways. Similarly, iso-osmotic and iso-tonic solutions are preferred. 

The most commonly described USP procedure for quantification is the scrap and elution approach. Low analyte recoveries can occur but can be minimized by using polar organic solvents such as methanol, ethanol, or acetone. Generally, analytes with high-Rf values can be desorbed with high recoveries by using the mobile phase. One example of this procedure is the USP assay procedure of the steroid methyl prednisolone acetate in cream formulation. This steroid is separated from its excipients by TLC, extracted from the sorbent, derivatized, and measured spectrophotometrically. 

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