Publications by authors named "Ann W Vickers"
The aims of this study were two-fold; first to report on the use of the novel InteliSite Companion device to deliver material to the colon, and second to use this new technology to assess the potential of mucoadhesive polymers to be retained in the large intestine. In this three-way crossover study in beagle dogs, two mucoadhesive polymers and a non-mucoadhesive polymer were remotely delivered in powder form to the colon. The retention of 150mg doses of the radiolabelled mucoadhesive polymers Carbopol 980 and polycarbophil AA-1, and the retention of ethylcellulose (control) in the colon of three canines was examined using gamma scintigraphy.
View Article and Find Full Text PDFPurpose: To develop a robust radiolabeling technique to enable evaluation of difficult to radiolabel gastric retentive formulations using gamma scintigraphy. The use of a successful radiolabel will allow accurate assessment of the gastric residence time of the formulations.
Materials And Methods: The retention of two radionuclides, indium ((111)In) and samarium ((153)Sm), with and without further processing to improve radiolabel performance were evaluated in simulated gastric pH in vitro.
Previous work has shown that polyethylene glycol 400 (PEG 400) has an accelerating effect on gastrointestinal transit and a modulating influence on drug absorption in humans. The aim of this study was to assess the impact of various excipients, PEG 400, propylene glycol, d-alpha-tocopheryl-polyethylene glycol-1000 succinate (TPGS) and Labrasol on gastrointestinal transit and drug absorption in four beagle dogs using scintigraphy. Each dog received, on five separate occasions, water (control) or a dose of excipient equivalent to 1 g PEG 400, 2 g propylene glycol, 1 g TPGS or 2 g Labrasol dissolved in water and administered in the form of two capsules.
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