A new approach to enhance efficiency of transdermal iontophoresis.

• Other Authors: Zhao, Li.
• Format: Others
• Language: English
• Published: Chinese University of Hong Kong 1996
• Subjects: Iontophoresis
• Online Access: http://library.cuhk.edu.hk/record=b5888741; http://repository.lib.cuhk.edu.hk/en/item/cuhk-321686

by Zhao Li. === Thesis (M.Phil.)--Chinese University of Hong Kong, 1996. === Includes bibliographical references (leaves 148-158). === ACKNOWLEDGMENTS --- p.I === ABSTRACT --- p.II === LIST OF FIGURES --- p.VIII === LIST OF TABLES --- p.X === LIST OF PHOTOGRAPHS --- p.XI === LIST OF EQUIPMENTS --- p.XII === LIST OF APPENDICES --- p.XII === ABBREVIATIONS --- p.XIII === Chapter Chapter 1. --- Introduction and Literature Review --- p.1 === Chapter I. --- Introduction --- p.1 === Chapter II. --- Literature Review --- p.6 === Chapter 1.1. --- Foreword --- p.6 === Chapter 1.2. --- Advantages of iontophoresis --- p.7 === Chapter 1.3. --- Historical background --- p.7 === Chapter 1.4. --- Definitions --- p.9 === Chapter 1.5. --- Principles of ionic transport in an electric field --- p.10 === Chapter 1.6. --- Theory and mechanism of iontophoretic delivery --- p.12 === Chapter 1.7. --- Development of iontophoretic devices --- p.13 === Chapter 1.8. --- Process of transdermal drug delivery --- p.14 === Chapter 1.9. --- Clinical application of iontophoresis --- p.14 === Chapter 1.10. --- Present problems of iontophoretic devices --- p.16 === Chapter 1.11. --- Effects of physiochemical factors on iontophoretic delivery --- p.20 === Chapter 1.11.1. --- pH --- p.20 === Chapter 1.11.2. --- Ionic strength --- p.21 === Chapter 1.11.3. --- Buffer solution --- p.21 === Chapter 1.11.4. --- Electrode --- p.22 === Chapter 1.11.5. --- Concentration and temperature --- p.22 === Chapter 1.11.6. --- Molecular weight --- p.22 === Chapter 1.11.7. --- Blood supply --- p.23 === Chapter 1.11.8. --- Pharmaceutical additives --- p.23 === Chapter 1.11.9. --- Four-electrodes system --- p.24 === Chapter 1.11.10. --- Skin properties --- p.24 === Chapter 1.12. --- Future prospect --- p.25 === Chapter Chanter 2. --- Design of PSPDC iontophoretic device === Chapter 2.1. --- Introduction --- p.29 === Chapter 2.2. --- Materials and Methods --- p.30 === Chapter 2.2.1. --- Principle of the new iontophoretic device --- p.30 === Chapter 2.2.2. --- Mechanism of pulsed short-circuit system --- p.32 === Chapter 2.2.3. --- Structure of self-made PSPDC device --- p.34 === Chapter 2.2.4. --- Safety system of the PSPDC device --- p.35 === Chapter 2.2.5. --- Test of the electrical properties of PSPDC device --- p.36 === Chapter 2.3. --- Results --- p.41 === Chapter 2.3.1. --- Efficacy of pulsed short-circuit system --- p.41 === Chapter 2.3.2. --- "Output characteristics of PDC, DC and PSPDC fields" --- p.42 === Chapter 2.3.3. --- Impact energy and depolarization action of PDC and PSPDC fields --- p.47 === Chapter 2.4. --- Discussion and Summary --- p.52 === Chapter 2.4.1. --- Discussion --- p.52 === Chapter 2.4.2. --- Summary --- p.53 === Chapter 2.5. --- Photochrome and Appendix --- p.56 === Chapter Chapter 3. --- Iontophoretic Experiment === Chapter 3.1. --- Introduction --- p.65 === Chapter 3.2. --- Materials and Methods --- p.67 === Materials --- p.67 === Methods --- p.68 === Chapter 3.2.1. --- Permeation experiments of different electric fields-an in vitro study --- p.69 === Chapter 3.2.2. --- Comparison of efficiency between DC and PSPDC-excised skin --- p.70 === Chapter 3.2.3. --- Comparison of permeation efficiency between DC and PSPDC- pedicled skin flap --- p.71 === Chapter 3.2.4. --- In vivo permeation experiment in the rat --- p.72 === Chapter 3.2.5. --- In vivo permeation experiment with the radioisotope labelled molecules --- p.73 === Chapter 3.2.6. --- Clinical observations of PSPDC iontophoresis device --- p.74 === Chapter 3.2.7. --- Experiments on the alteration and recovery of skin impedance under prolonged iontophoresis --- p.75 === Chapter 3.2.8. --- Skin damage by iontophoresis --- p.76 === Chapter 3.3. --- Results: --- p.77 === Chapter 3.3.1. --- Permeation rates of different electric fields (in vitro: excised rat skin) --- p.77 === Chapter 3.3.2. --- Comparison between DC and PSPDC-- excised rat skin --- p.78 === Chapter 3.3.3. --- Comparison between DC and PSPDC-- pedicled skin --- p.79 === Chapter 3.3.4. --- In vivo permeation experiment in the rat --- p.80 === Chapter 3.3.5. --- In vivo permeation experiment with radioisotope labelled molecules --- p.81 === Chapter 3.3.6. --- Alteration and recovers of skin impedance under prolonged iontophoresis --- p.88 === Chapter 3.3.7. --- Observing skin damage by iontophoresis --- p.89 === Chapter 3.3.8. --- Clinical observation of PSPDC iontophoresis device --- p.90 === Chapter 3.4. --- Discussion and summary --- p.91 === Chapter 3.4.1. --- Discussion --- p.91 === Chapter 3.4.2. --- Summary --- p.96 === Chapter 3.5. --- Photochrome and Appendix --- p.97 === Chapter Chapter 4. --- Electrical properties of scar skin and normal skin === Chapter 4.1. --- Introduction --- p.104 === Chapter 4.2. --- Material and method --- p.106 === Chapter 4.2.1. --- Principle of four point measurement method --- p.106 === Chapter 4.2.2. --- Measurement of electrical impedance of scar and skin with four point method --- p.107 === Chapter 4.2.3. --- Principle of three point measurement method --- p.108 === Chapter 4.2.4. --- Measurement of impedance of scar and skin with three point method --- p.110 === Chapter 4.2.5. --- Imitation equivalent circuit of normal skin with two point method --- p.111 === Chapter 4.3. --- Results --- p.113 === Chapter 4.3.1. --- Impedance of scar tissue and skin tissue with four point method --- p.113 === Chapter 4.3.2. --- Measurement of impedance of scar tissue and skin with three point method --- p.117 === Chapter 4.3.3. --- "Relationship of resistance, reactance, impedance and frequency" --- p.123 === Chapter 4.3.4. --- Imitation equivalence circuit of normal skin with point method --- p.124 === Chapter 4.4. --- Discussion and Summary --- p.125 === Chapter 4.4.1. --- Discussion --- p.125 === Chapter 4.4.2. --- Summary --- p.131 === Chapter 4.5. --- Photochrome and Appendix --- p.132 === Chapter Chapter 5. --- General discussion and conclusion === Chapter 5.1. --- General discussion --- p.137 === Chapter 5.2. --- Conclusion --- p.143 === References I --- p.148 === References II --- p.158 === LIST OF FIGURES === Fig. 2. 1. Imitating waveform of 1:1PDC and 12:1 PSPDC fields --- p.32 === Fig. 2. 2. The circuit of Pulsed short-circuit in PSPDC system --- p.32 === Fig. 2. 3. Block diagram of PSPDC system --- p.35 === Fig. 2. 4. Scheme of measuring short-circuit action of PSPDC apparatus --- p.36 === Fig. 2. 5. Measurement of EP of several electric fields --- p.37 === Fig. 2. 6. Measurement of impact energy and depolarization action --- p.39 === Fig. 2. 7. The distribution of permeating current and releasing current --- p.41 === Fig. 2. 8. Comparing the polarization degree of different electric fields --- p.42 === Fig. 2. 9. Comparing alternating current component of electric fields --- p.43