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.)


Pharmaceutical and Chemical Sciences

First Advisor

Jianhua Ren

First Committee Member

Ryan Moffet

Second Committee Member

Jianhua Ren

Third Committee Member

Jerry Tsai


The thesis describes utilizing mass spectrometry and computational methods to study two groups of molecular systems: small organic molecules and oligopeptides. The gas-phase acidities were measured and the structures of the molecular species were calculated. The small molecules investigated included methylparaben, ibuprofen, and triclosan, all known to have some biological activity. The gas-phase acidity measurements made for these small molecules had the solvent and collisional gas pressures adjusted in order to observe their potential influences. The results obtained provide insight into the ion chemistry of these molecules and how the energetics may change the observed behavior of the ion as well as the resulting thermochemical properties measured. The oligopeptides studied were a family of tri-peptides in which a cysteine probe was placed within an alanine backbone. The cysteine probe was either in the L- or D- configuration in order to detect any fundamental differences among the diastereotopic peptides. Compared to the L-cysteine isomers, the D-cysteine peptides appear to display a change in gas-phase behavior and their respective dissociation profiles. These changes may have an implication of altering the biochemical properties when chirality changes in biological systems.





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

Find in ProQuest



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).