Campus Access Only

All rights reserved. This publication is intended for use solely by faculty, students, and staff of University of the Pacific. No part of this publication may be reproduced, distributed, or transmitted in any form or by any means, now known or later developed, including but not limited to photocopying, recording, or other electronic or mechanical methods, without the prior written permission of the author or the publisher.

Date of Award


Document Type

Thesis - Pacific Access Restricted

Degree Name

Master of Science (M.S.)


Graduate School

First Advisor

Ravindra C. Vasavada

First Committee Member

Marvin H. Malone

Second Committee Member

Donald Y. Barker


The solubility and dissolution of famotidine from solid glass dispersions of xylitol, prepared by the fusion method, were investigated. Preliminary stability studies revealed that famotidine was stable for 72 hours (< 0.5% decomposition) in water at 37° ± 0.5° C. Both the drug and the carrier were stable and did not decompose during the fusion process. About 4% decomposition of famotidine was observed after 72 hours in an aqueous solution of famotidine:xylitol glass dispersion at 37° ± 0.5° C. Solubility of famotidine from solid glass dispersions and physical mixtures with famotidine:xylitol ratios of 1:1, 1:20 and 1:40 was studied at 37° ± 0.5° C and found to be higher than that of famotidine alone in water. The solubility of famotidine from physical mixtures increased linearly with the increase in xylitol concentration, but the relationship was not linear for glass dispersions. The dispersions were more effective in enhancing the solubility of famotidine as compared to physical mixtures of corresponding drug:carrier ratios. A 1:40 glass dispersion increased the solubility by up to 32% while the solubility increase from a 1:40 physical mixture was 14%. Dissolution studies were carried out on glass dispersions with famotidine:xylitol ratios of 1:1, 1:10 and 1:20 in water at 37° ± 0.5° C. Results revealed a marked increase in the dissolution rate of famotidine from solid glass dispersions when compared to the dissolution rate of plain famotidine powder alone. The increase was greatest at the lowest drug level (1:20 drug:carrier ratio) with 100% of the drug dissolving within one minute.

The glass dispersions were subjected to thermal analysis. Thermograms obtained by differential scanning calorimetry showed no evidence of chemical interaction between famotidine and xylitol. Phase diagrams were constructed for famotidine:xylitol solid glass dispersions and physical mixtures from melting temperatures determined by the capacity tube method. The phase diagram of the dispersion system suggested the formation of a eutectic mixture of famotidine and xylitol near a drug:carrier ratio of 1:40.



To access this thesis/dissertation you must have a valid email address and log-in to Scholarly Commons.

Find in PacificSearch



If you are the author and would like to grant permission to make your work openly accessible, please email


Rights Statement

Rights Statement

In Copyright. URI:
This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).