Nanoparticle Stabilized Liposomes for Acne Therapy

65 Pages·2012·1.62 MB·English

UC San Diego
UC San Diego Electronic Theses and Dissertations
Title
Nanoparticle Stabilized Liposomes for Acne Therapy
Permalink
https://escholarship.org/uc/item/5wk9r4n5
Author
Fu, Victoria
Publication Date
2013

Peer reviewed|Thesis/dissertation
eScholarship.org Powered by the California Digital Library
University of California
UNIVERSITY OF CALIFORNIA, SAN DIEGO

Nanoparticle Stabilized Liposomes for Acne Therapy

A Thesis submitted in partial satisfaction of the requirements for the degree
Master of Science

in

Nanoengineering

by

Victoria Fu

Committee in charge:
Professor Liangfang Zhang, Chair
Professor Michael Heller
Professor Don Sirbuly

2013
Copyright
Victoria Fu, 2013
All rights reserved.
ii
The Thesis of Victoria Fu is approved, and it is acceptable in quality and form for
publication on microfilm and electronically:

Chair

University of California, San Diego
2013
iii
DEDICATION

This work is dedicated to each member of the Fu family: Dad, Mom, Kath, Ryan, and
Scooter. Despite being so far apart from each other, you all have been able to provide the
ample support I needed through my time here at UCSD. You all have truly shown me that
love knows no bounds. Thank you for always believing that I could do great things. I
couldn’t be luckier!

iv
EPIGRAPH

“Far and away the best prize that life has to offer is the chance to work hard at work
worth doing.”
Theodore Roosevelt
v
TABLE OF CONTENTS

Signature Page……………………………………………………………………... iii
Dedication………………………………………………………………………….. iv
Epigraph……………………………………………………………………………. v
Table of Contents…………………………………………………………………... vi
List of Figures………………………………………………………………….…... viii
List of Tables………………………………………………………………..…....... x
Acknowledgements…………………………………………………………....…… xi
Vita…………………………………………………………………………...…...... xiii
Abstract of the Thesis……………………………………………….………….….. xiv
Chapter 1. Liposomes for Acne Therapy………………………………………....... 1
1.1 - An Introduction to Acne……………………………………………… 1
1.2 - The Advantages of using Liposomes as an Acne Therapy……..…...... 3

Chapter 2. Fatty Acid Loaded Liposomes for Acne Therapy……………………… 9
2.1 - Introduction…………………………………………………...…........ 9
2.2 - Experimental Methods…………………………………………..…..... 12
2.2.1 - Materials…………………………………………...……...... 12
2.2.2 - Preparation of bacteria……………………………...……..... 12
2.2.3 - Preparation of LipoLA and LipoLA gel.…………….…....... 13
2.2.4 - Fusion study between LipoLA and P. acnes..……………..... 14
2.2.5 - In vitro antimicrobial activity of LipoLA against
P. acnes and bacterial morphology study………..………… 14
2.2.6 - In vivo antimicrobial activity of LipoLA against
P. acnes through intradermal injection……………….......... 15
2.2.7 - In vivo therapeutic efficacy of LipoLA against
acne infection through topical administration….…....……... 16
2.2.8 - Skin toxicity………………………………..…..………........ 16
2.3 - Interaction between LipoLA and P. acnes bacteria……...……..….…. 17
2.4 - In vitro antimicrobial activity ad bacterial morphology……………… 19
2.5 - In vivo antimicrobial activity…………………………………….…... 20
2.6 - In vivo therapeutic efficacy………………………………………....... 22
2.7 - Toxicity of LipoLA to normal skin tissues…………………………… 24
2.8 - Conclusion……………………………………………………………. 26

vi
Chapter 3. Nanoparticle Stabilized Liposomes for Acne Therapy……………….... 27
3.1 - An Introduction to Liposome Stabilization..……………………......... 27
3.2 - Experimental Methods..................................................................…..... 28
3.2.1 - Materials………………………………………………......... 28
3.2.2 - Preparation of carboxyl-terminated gold nanoparticles…...... 29
3.2.3 - Preparation and characterization of AuC-Liposomes
and AuC-Liposome gel..………………………….……....... 29
3.2.4 - Doxycycline Drug Release Study………….……………...... 30
3.2.5 - Preparation of P. acnes bacteria………………………….……. 31
3.2.6 - In vitro antimicrobial efficacy study….………………......... 31
3.2.7 - In vivo antimicrobial efficacy study…………….…....…...... 32
3.2.8 - Skin toxicity……………………………………………….... 32
3.2.9 - Fusion stability study…………………………………..….... 33
3.3 - Synthesizing Nanoparticle Stabilized Liposomes..……...……..…...... 33
3.4 - The Antimicrobial Efficacy of AuC-Liposomes……………………... 37
3.5 - A Toxicity Study of AuC-Liposomes……………………………….... 39
3.6 - The Long Term Stability of AuC-Liposomes……………………........ 41
3.7 - Conclusion……………………………………………………………. 45

References………………………………………………………………………….. 46

vii
LIST OF FIGURES

Figure 1.1 – A schematic illustration of the liposome platform and its
components……………………………………………………………………….... 4

Figure 2.1 – A schematic illustration of liposomal lauric acids (LipoLA) to treat
acne infection caused by Propionibacterium acnes (P. acnes)
bacteria.…………………………………………………………………………….. 11

Figure 2.2 – FRET measurements of the fusion activity between LipoLA and P.
acnes bacteria………………………………………………………………………. 18

Figure 2.3 – The in vitro antimicrobial activity of LipoLA against P. acnes and
morphology of P. acnes after LipoLA treatment…………………………………... 19

Figure 2.4 – The in vivo antimicrobial activity of LipoLA against P. acnes
through intradermal injection. ……………………………..............................….. 21

Figure 2.5 – The in vivo therapeutic efficacy of LipoLA for the treatment of P.
acnes infection through topical administration.………………………………….... 23

Figure 2.6 – A toxicity study of LipoLA on mouse back skin. LipoLA gel was
topically applied onto shaved mouse back skin (n=6 per group).………………..... 24

Figure 3.1 – A schematic illustration of the pH responsive, nanoparticle stabilized
liposome platform..................................................................................................... 34

Figure 3.2 – A basic characterization of bare liposomes loaded with varying
concentrations of antibiotics………..……………………………………………… 35

Figure 3.3 – A basic characterization study of bare liposomes and nanoparticle
stabilized liposomes was carried out to measure zeta potential and particle size..... 36

Figure 3.4 – A doxycycline release study based on varying pH environments…… 36

Figure 3.5 – An in vitro Antimicrobial Efficacy Study of AuC-liposomes.………. 38

Figure 3.6 – An in vivo Antimicrobial Efficacy Study of AuC-liposomes.….......... 39

Figure 3.7 – A seven day, in vivo toxicity study of the AuC-lipsoome topical gel
formulation was conducted and scored using the Draize scoring system for
irritation.……………………………………………………………………………. 40

viii
Figure 3.8 – An in vivo toxicity study comparing AuC-liposomes to the top two
over the counter drugs available for acne therapy. ……………………………….. 40

Figure 3.9 – A long term stability study measuring particle size of AuC-
liposomes over a 3 month period…………………………………………………... 42

Figure 3.10 – A long term stability study measuring the fusion capacity of
liposomes against P. acnes over a 3 month period…………………………………. 43

Figure 3.11 – A fusion capacity comparison study was performed on AuC-
liposomes, stored for six weeks, before and after a pH environment adjustment
from pH = 7.4 to pH = 4 at ………………………………………………………... 44

ix