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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
621

The lectins from the Chinese herb, tianhuafen, purification and characterization.

January 1982 (has links)
by Wong Dart-man. / Bibliography: leaves 107-114 / Thesis (M.Phil.)--Chinese University of Hong Kong, 1982
622

A voltammetric study of some active ingredients in cough drugs.

January 1987 (has links)
by Lau Yick Ki. / Thesis (M.Ph.)--Chinese University of Hong Kong, 1987. / Includes bibliographies.
623

Determination of organic compounds by high-performance liquid chromatography with conductometric detection.

January 1993 (has links)
by Chuen-shing Mok. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1993. / Includes bibliographical references (leaves 192-193). / Chapter Chapter 1 --- INTRODUCTION --- p.1 / Chapter Chapter 2 --- INSTRUMENTATION AND THEORY --- p.9 / Chapter Chapter 3 --- INDIRECT CONDUCTOMETRIC DETECTION OF AMINO ACIDS AFTER HIGH-PERFORMANCE LIQUID CHROMATOGRAPHIC SEPARATION --- p.17 / Chapter Chapter 4 --- DETERMINATION OF MONOSODIUM GLUTAMATE IN FOODS WITH HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY USING INDIRECT CONDUCTOMETRIC DETECTION --- p.52 / Chapter Chapter 5 --- HIGH-PERFORMANCE LIQUID CHROMATOGRAPHIC DETERMINATION OF ACTIVE INGREDIENTS IN COUGH-COLD SYRUPS WITH INDIRECT CONDUCTOMETRIC DETECTION --- p.83 / Chapter Chapter 6 --- HIGH-PERFORMANCE LIQUID CHROMATOGRAPHIC DETERMINATION OF ATROPINE AND ATROPINE- LIKE ALKALOIDS IN PHARMACEUTICAL PREPARATIONS WITH INDIRECT CONDUCTOMETRIC DETECTION --- p.144 / Chapter Chapter 7 --- CONCLUSION --- p.194
624

Gas chromatography-mass fragmentographic analysis of serum 1[alpha], 25-dihydroxyvitamin D3.

January 1991 (has links)
by Priscilla Miu-kuen Poon. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1991. / Includes bibliographical references. / ACKNOWLEDGEMENT --- p.1 / ABSTRACT --- p.2 / CONTENTS / Chapter 1. --- INTRODUCTION --- p.4 / Chapter 1.1 --- Discovery of vitamin D / Chapter 1.2 --- Bioavailability of vitamin D and its metabolites / Chapter 1.3 --- Metabolism of vitamin D and its metabolites / Chapter 1.4 --- Mode of action of vitamin D / Chapter 1.5 --- Vitamin D-related diseases / Chapter 2. --- METHODS OF MEASURING VITAMIN D AND ITS METABOLITES --- p.32 / Chapter 2.1 --- Deproteinization / Chapter 2.2 --- Extraction / Chapter 2.3 --- Separation / Chapter 2.4 --- Quantitation / Chapter 3. --- OBJECTIVES --- p.51 / Chapter 4. --- MATERIALS & METHODS --- p.52 / Chapter 4.1 --- Materials / Chapter 4.2 --- General methods / Chapter 4.3 --- Blood collection / Chapter 4.4 --- Radioreceptor assay / Chapter 4.5 --- Serum treatment / Chapter 4.6 --- High Performance Liquid Chromatography (HPLC) / Chapter 4.7 --- Gas Chromatography-Mass Spectrometry (GC-MS) / Chapter 4.8 --- "Serum 1α,25-dihydroxyvitamin D3 analysis" / Chapter 4.9 --- Application of the established GC-MS method / Chapter 4.10 --- Study on hypercalcaemia of tuberculosis / Chapter 5. --- RESULTS --- p.66 / Chapter 5.1 --- Analysis of vitamin D3 standard / Chapter 5.2 --- "Analysis of 1α,25-dihydroxyvitamin D3 standard" / Chapter 5.3 --- Separation of vitamin D3 metabolites / Chapter 5.4 --- "Analysis of lα,25-dihydroxyvitamin D3 in serum samples" / Chapter 5.5 --- Study on hypercalcaemia of tuberculosis / Chapter 6. --- DISCUSSIONS --- p.118 / Chapter 6.1 --- Derivatization / Chapter 6.2 --- Optimization of GC-MS parameters / Chapter 6.3 --- Sample pre-treatment / Chapter 6.4 --- "GC-MS analysis of serum lα,25-dihydroxyvitamin D3" / Chapter 6.5 --- Study on hypercalcaemia of tuberculosis / Chapter 7. --- CONCLUSION --- p.129 / LIST OF ABBREVIATIONS --- p.131 / LIST OF FIGURES --- p.134 / LIST OF TABLES --- p.137 / REFERENCES --- p.139
625

Analysis of amino acids in food samples by high performance liquid chromatography using conductometric detection.

January 1999 (has links)
Poon Wai Mei Emily. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 74-81). / Abstracts in English and Chinese. / Chapter Chapter 1: --- Introduction --- p.1 / Chapter 1.1. --- Importance of amino acids --- p.1 / Chapter 1.1.1. --- Clinical samples --- p.1 / Chapter 1.1.2. --- Food samples --- p.2 / Chapter 1.2. --- Reviews of amino acid analysis --- p.6 / Chapter 1.2.1. --- Ion-exchange chromatography --- p.6 / Chapter 1.2.2. --- Gas chromatography --- p.6 / Chapter 1.2.3. --- Thin layer chromatography --- p.8 / Chapter 1.2.4. --- Flow injection analysis --- p.8 / Chapter 1.2.5. --- Liquid chromatography --- p.9 / Chapter 1.2.6. --- Capillary electrophoresis --- p.10 / Chapter 1.2.7. --- Methods of detecting amino acid without derivatization --- p.11 / Chapter 1.3. --- Determination of amino acids by reversed-phase ion-pair chromatography --- p.12 / Chapter 1.4. --- The objectives of the study --- p.15 / Chapter Chapter 2: --- Experimental --- p.16 / Chapter 2.1. --- Materials --- p.16 / Chapter 2.2. --- Apparatus --- p.16 / Chapter 2.3. --- Samples --- p.16 / Chapter 2.4. --- Procedures --- p.17 / Chapter 2.4.1. --- Preparation of amino acid standard solution (stock solutions) --- p.17 / Chapter 2.4.2. --- Method development --- p.17 / Chapter 2.4.3. --- Samples preparation --- p.18 / Chapter 2.4.4. --- Preparation of Dowex column --- p.18 / Chapter 2.4.5. --- Extraction of amino acids from samples --- p.19 / Chapter 2.4.6. --- Recovery test --- p.20 / Chapter Chapter 3: --- Results and Discussions --- p.21 / Chapter 3.1. --- Optimization --- p.21 / Chapter 3.1.1. --- pH --- p.21 / Chapter 3.1.2. --- Ion-interacting reagent --- p.22 / Chapter 3.1.3. --- Organic solvent --- p.29 / Chapter 3.1.4. --- Temperature --- p.34 / Chapter 3.1.5. --- Chromatographic conditions --- p.36 / Chapter 3.2. --- Application --- p.45 / Chapter 3.2.1. --- Precision of injection --- p.45 / Chapter 3.2.2. --- Accuracy of the method --- p.46 / Chapter 3.2.3. --- The concentration of amino acids in food samples --- p.50 / Chapter 3.2.3.1. --- Citrus fruits --- p.50 / Chapter 3.2.3.2. --- Orange juice drinks --- p.60 / Chapter 3.2.3.3. --- Chinese honey --- p.65 / Chapter 3.2.3.4. --- New Zealand honey --- p.67 / Chapter 3.2.3.5. --- Energy drinks --- p.70 / Chapter Chapter 4 : --- Conclusion --- p.72 / Chapter Chapter 5 : --- Bibliographies --- p.74 / Chapter 6. --- Appendices --- p.82 / Chapter 6.1. --- Table 1 : Ingredients of orange juice drinks --- p.82 / Chapter 6.2. --- Table 2 : Honey samples --- p.83 / Chapter 6.3. --- Table 3 : Ingredients of energy drinks --- p.83
626

HPLC method development for the analysis of electroplating baths used in the electronic industry.

January 2002 (has links)
Sin Wai-Chu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references. / Abstracts in English and Chinese. / ABSTRACT --- p.i / 論文摘要 --- p.ii / ACKNOWLEDGEMENT --- p.iii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Electroplating history --- p.1 / Chapter 1.2 --- Electroplating bath --- p.7 / Chapter 1.3 --- Electroplating analytical methods --- p.8 / Chapter 1.3.1 --- Metal content and elemental impurities analysis --- p.10 / Chapter 1.3.2 --- "Metal complex, inorganic anion and cation analysis" --- p.11 / Chapter 1.3.3 --- Organic brighteners and levelers analysis --- p.12 / Chapter 1.4 --- HPLC literature review --- p.15 / Chapter 1.5 --- My research work --- p.16 / Chapter 1.6 --- References for Chapter 1 --- p.19 / Chapter Chapter 2 --- General Experimental --- p.23 / Chapter 2.1 --- The HPLC System --- p.23 / Chapter 2.2 --- The factors that affect the separation --- p.26 / Chapter 2.2.1 --- The composition of the solvent system --- p.27 / Chapter 2.2.2 --- The selection of column --- p.30 / Chapter 2.2.3 --- The most suitable analytical wavelength for UV detection --- p.34 / Chapter 2.3 --- Challenges in analyzing electroplating baths solution --- p.35 / Chapter 2.3.1 --- High metal content --- p.36 / Chapter 2.3.2 --- Strong ligand or complexing agent --- p.36 / Chapter 2.3.3 --- Interference --- p.37 / Chapter 2.3.4 --- Extreme pH --- p.37 / Chapter 2.3.5 --- Other difficulties --- p.38 / Chapter 2.3.6 --- Maintenance of HPLC instrument --- p.38 / Chapter 2.4 --- References for Chapter 2 --- p.38 / Chapter Chapter 3 --- Palladure 200 bath HPLC analysis --- p.41 / Chapter 3.1 --- Introduction --- p.41 / Chapter 3.2 --- Experimental --- p.43 / Chapter 3.3 --- Problems in the existing UV analysis for monitoring Palladure200 process --- p.45 / Chapter 3.4 --- HPLC method development for monitoring Palladure 200 process --- p.49 / Chapter 3.5 --- Analysis of aged Palladure 200 plating bath from production line --- p.55 / Chapter 3.6 --- Conclusion --- p.57 / Chapter 3.7 --- References for Chapter 3 --- p.58 / Chapter Chapter 4 --- Nickel PC3 bath HPLC analysis --- p.59 / Chapter 4.1 --- Introduction --- p.59 / Chapter 4.2 --- Experimental --- p.60 / Chapter 4.3 --- Problems in the existing Titration method for monitoring Nickel PC3 process --- p.62 / Chapter 4.4 --- HPLC method development for monitoring Nickel PC3 process --- p.63 / Chapter 4.4.1 --- Identify individual component of Nickel PC3 process --- p.63 / Chapter 4.4.2 --- Set up a calibration curve for the Nickel PC3 Additive --- p.67 / Chapter 4.4.3 --- Analysis of aged Nickel PC3 plating bath from production line --- p.68 / Chapter 4.5 --- Conclusion --- p.71 / Chapter 4.6 --- References for Chapter 4 --- p.72 / Chapter Chapter 5 --- Solderon SC bath HPLC analysis --- p.73 / Chapter 5.1 --- Introduction --- p.73 / Chapter 5.2 --- Experimental --- p.74 / Chapter 5.3 --- Instability in the existing Cyclic Voltammetric Stripping (CVS) method for monitoring Solderon SC process --- p.76 / Chapter 5.4 --- HPLC method development for monitoring Solderon SC process --- p.77 / Chapter 5.4.1 --- Identify the individual components --- p.77 / Chapter 5.4.2 --- Set up a calibration curve for the Solderon SC Primary --- p.82 / Chapter 5.4.3 --- Analysis of aged Solderon SC plating bath from production line --- p.84 / Chapter 5.5 --- Conclusion --- p.86 / Chapter 5.6 --- References for Chapter 5 --- p.86 / Chapter Chapter 6 --- Copper Gleam PPR bath HPLC analysis --- p.87 / Chapter 6.1 --- Introduction --- p.87 / Chapter 6.2 --- Experimental --- p.89 / Chapter 6.3 --- Problems in the existing Cyclic Voltammetric Stripping (CVS) method for monitoring Copper Gleam PPR process --- p.91 / Chapter 6.4 --- HPLC method development for monitoring Copper Gleam PPR process --- p.92 / Chapter 6.4.1 --- Identify Individual components and copper PPR additivein standard bath --- p.92 / Chapter 6.4.2 --- Set up a calibration curve for the Copper Gleam PPR Additive --- p.95 / Chapter 6.4.3 --- Analysis of aged Copper Gleam PPR plating bath from production line --- p.96 / Chapter 6.4.5 --- Study of H202 effect --- p.101 / Chapter 6.4.6 --- Study of air agitation effect --- p.104 / Chapter 6.4.7 --- Study of Copper anode effect --- p.105 / Chapter 6.5 --- Conclusion --- p.107 / Chapter 6.6 --- References for Chapter 6 --- p.107 / Chapter Chapter 7 --- Silverjet220 bath HPLC analysis --- p.109 / Chapter 7.1 --- Introduction --- p.109 / Chapter 7.2 --- Experimental --- p.110 / Chapter 7.3 --- HPLC method development for monitoring Silverjet 220 process --- p.112 / Chapter 7.3.1 --- Identify individual components and Silverjet 220 Additive in the plating bath --- p.112 / Chapter 7.3.2 --- Optimize the condition for HPLC analysis --- p.117 / Chapter 7.3.3 --- Analysis of aged Silverjet 220 plating bath from production line --- p.119 / Chapter 7.4 --- Conclusion --- p.122 / Chapter 7.5 --- References for Chapter 7 --- p.123 / Chapter Chapter 8 --- Conclusions and Further Studies --- p.124 / Chapter 8.1 --- Conclusions --- p.124 / Chapter 8.2 --- Further Studies --- p.126 / APPENDIX --- p.128 / The User guide for HPLC --- p.128 / HPLC System Calibration Maintenance --- p.135 / HPLC System Preventive Maintenance --- p.145
627

Qualitative and quantitative analysis of aconitine alkaloids in Chinese medicinal materials by high performance liquid chromatography and atmospheric pressure ionization mass spectrometry.

January 1998 (has links)
by Kwok Chiu Nga. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 1-3 (4th gp.)). / Abstract also in Chinese. / TABLE OF CONTENTS --- p.i / ABSTRACT --- p.iv / 摘要 --- p.vi / LIST OF FIGURES --- p.vii / LIST OF TABLES --- p.x / ABBREVIATION --- p.xi / Chapter CHAPTER ONE --- RESEARCH BACKGROUND / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.1.1 --- Alkaloids --- p.1 / Chapter 1.1.2 --- Diterpenoid alkaloids --- p.2 / Chapter 1.1.3 --- Aconitine-type alkaloids --- p.2 / Chapter 1.1.4 --- Toxicity --- p.4 / Chapter 1.1.5 --- Safety concerns --- p.4 / Chapter 1.2 --- Summary of the Previous Work --- p.8 / Chapter 1.3 --- Objectives and Outline of the Present Work --- p.13 / Chapter CHAPTER TWO --- INSTRUMENTATION AND EXPERIMENTAL / Chapter 2.1 --- Instrumentation --- p.15 / Chapter 2.1.1 --- High performance liquid chromatography (HPLC) --- p.15 / Chapter 2.1.2 --- Triple-stage quadrupole (TSQ) mass spectrometer --- p.17 / Chapter 2.1.2.1 --- Atmospheric pressure chemical ionization (APCI) --- p.17 / Chapter 2.1.2.2 --- Electrospray ionization (ESI) --- p.20 / Chapter 2.1.2.3 --- Quadrupole system --- p.20 / Chapter 2.1.2.4 --- Ion detection system --- p.22 / Chapter 2.1.2.5 --- Data system --- p.22 / Chapter 2.2 --- Experimental --- p.22 / Chapter 2.2.1 --- Sample and reagents --- p.22 / Chapter 2.2.2 --- Sample preparation --- p.23 / Chapter 2.2.3 --- High performance liquid chromatography conditions --- p.23 / Chapter 2.2.4 --- Mass spectrometry conditions --- p.25 / Chapter 2.2.4.1 --- Atmospheric pressure chemical ionization conditions --- p.25 / Chapter 2.2.4.2 --- Electrospray ionization conditions --- p.25 / Chapter CHAPTER THREE --- SELECTION AND OPTIMIZATION OF HPLC/MS METHOD / Chapter 3.1 --- Introduction --- p.26 / Chapter 3.2 --- Experimental --- p.29 / Chapter 3.3 --- Results and Discussion --- p.29 / Chapter 3.3.1 --- Triethylamine concentration --- p.31 / Chapter 3.3.2 --- Ammonium acetate concentration --- p.34 / Chapter 3.3.3 --- Acetic acid concentration --- p.37 / Chapter 3.3.4 --- HPLC/MS interface --- p.40 / Chapter 3.3.5 --- MS/MS conditions --- p.40 / Chapter 3.4 --- Conclusions --- p.43 / Chapter CHAPTER FOUR --- DETERMINATION OF ACONITINE-TYPE ALKALOIDS IN ACONITE ROOTS / Chapter 4.1 --- Introduction --- p.48 / Chapter 4.2 --- Experimental --- p.48 / Chapter 4.3 --- Results and Discussion --- p.50 / Chapter 4.3.1 --- Selection of internal standard --- p.50 / Chapter 4.3.2 --- Method validation --- p.50 / Chapter 4.3.2.1 --- Precision of measurement --- p.50 / Chapter 4.3.2.2 --- Accuracy of measurement --- p.50 / Chapter 4.3.2.3 --- Limits of detection and quantitation --- p.58 / Chapter 4.3.3 --- Determination of aconitine-type alkaloids in aconite roots --- p.58 / Chapter 4.4 --- Conclusions --- p.60 / Chapter CHAPTER FIVE --- CONCLUSIONS AND FUTURE WORK / Chapter 5.1 --- Conclusions --- p.67 / Chapter 5.2 --- Future Work --- p.68 / ACKNOWLEDGMENT --- p.A1 / APPENDIX --- p.A2 / REFERENCES --- p.R1
628

Recognition of Chinese medicinal herbs by gas chromatgraphy [sic]. / Recognition of Chinese medicinal herbs by gas chromatography

January 1998 (has links)
by Suk Che Ho. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 86-88). / Abstract also in Chinese. / Abstract --- p.i / Acknowledgments --- p.iii / Dedication --- p.iv / Abbreviations --- p.v / Table of Contents --- p.vi / Chapter Chapter 1: --- Introduction --- p.1 / Chapter 1.1 --- Overview of Chinese Medicinal Herbs containing essential oils --- p.1 / Chapter 1.1.1 --- Introduction of Chinese Medicinal Herbs --- p.1 / Chapter 1.1.2 --- Chinese Medicinal Herbs containing essential oils --- p.2 / Chapter 1.2 --- Recognition of Chinese Medicinal Herbs --- p.2 / Chapter 1.2.1 --- Traditional method in recognition of Chinese Medicinal Herbs (CMH) --- p.2 / Chapter 1.2.2 --- Instrumental Methods for the recognition of CMH --- p.4 / Chapter 1.2.3 --- The use of GC and GC/MS on CMH --- p.4 / Chapter 1.3 --- Motivation and objective of this research --- p.5 / Chapter 1.3.1 --- Motivation --- p.6 / Chapter 1.3.2 --- Objective of this research --- p.7 / Chapter 1.4 --- Outline of the methodology and arrangement of the thesis --- p.8 / Chapter Chapter 2: --- Experimental Setup --- p.11 / Chapter 2.1 --- Reagents and materials --- p.11 / Chapter 2.1.1 --- Reagents and glassware --- p.11 / Chapter 2.1.2 --- Materials --- p.11 / Chapter 2.2 --- Sample pretreatment --- p.14 / Chapter 2.3 --- Extraction of essential oils from the herbal samples --- p.14 / Chapter 2.3.1 --- Traditional extraction methods for essential oils --- p.14 / Chapter 2.3.2 --- Extraction by hydrodistillation using Dean and Stark-type trap --- p.15 / Chapter 2.4 --- Results --- p.17 / Chapter 2.4.1 --- Comparison with literature data --- p.17 / Chapter 2.4.2 --- Reproducibility of the extraction --- p.17 / Chapter 2.4.3 --- Recovery test --- p.26 / Chapter 2.5 --- Discussion --- p.27 / Chapter Chapter3: --- Instrumental Analysis of the Essential Oils --- p.29 / Chapter 3.1 --- GC analysis --- p.29 / Chapter 3.1.1 --- Instrumentation --- p.29 / Chapter 3.1.2 --- Instrumental settings --- p.31 / Chapter 3.1.3 --- The use of GC in the analysis of essential oils --- p.31 / Chapter 3.1.3.1 --- Qualitative data --- p.31 / Chapter 3.1.3.2 --- Quantitative data --- p.33 / Chapter 3.1.3.3 --- Dilution strategy --- p.33 / Chapter 3.1.4 --- Results --- p.36 / Chapter 3.1.4.1 --- Precision test --- p.36 / Chapter 3.1.4.2 --- Linearity --- p.39 / Chapter 3.2 --- GC/MS analysis --- p.41 / Chapter 3.2.1 --- Instrumentation --- p.41 / Chapter 3.2.2 --- Instrumental settings --- p.42 / Chapter 3.2.3 --- The use of GC/MS in the analysis of essential oils --- p.43 / Chapter 3.2.3.1 --- Identification by GC/MS --- p.43 / Chapter 3.2.3.2 --- Abundance information --- p.43 / Chapter 3.2.4 --- Results --- p.44 / Chapter 3.2.4.1 --- Precision test --- p.44 / Chapter 3.2.4.2 --- Linearity --- p.46 / Chapter 3.2.4.3 --- Detection limit --- p.48 / Chapter 3.2.4.4 --- Chromatographic patterns of herbal samples obtained by GC/MS --- p.49 / Chapter 3.3 --- Discussion --- p.49 / Chapter Chapter 4: --- Development of a system for recognition --- p.52 / Chapter 4.1 --- Introduction --- p.52 / Chapter 4.2 --- Analysis of chromatographic patterns --- p.53 / Chapter 4.2.1 --- Extraction of “effective´ح peaks --- p.54 / Chapter 4.2.2 --- Extraction of “characteristic´ح peaks --- p.56 / Chapter 4.3 --- Library section --- p.60 / Chapter 4.3.1 --- Calculation of relative retention indices --- p.60 / Chapter 4.3.2 --- Normalization factors --- p.61 / Chapter 4.4 --- Matching section --- p.62 / Chapter 4.4.1 --- Overview of the matching method --- p.62 / Chapter 4.4.2 --- Input --- p.63 / Chapter 4.4.3 --- Matching strategy --- p.64 / Chapter 4.4.4 --- Matching algorithms --- p.64 / Chapter 4.4.4.1 --- "Matching with “characteristic"" peaks" --- p.64 / Chapter 4.4.4.2 --- Matching with “effective´ح peaks --- p.65 / Chapter 4.4.5 --- Calculation of similarity scores --- p.66 / Chapter 4.4.6 --- Output --- p.69 / Chapter Chapter 5: --- Performance of the proposed recognition system --- p.70 / Chapter 5.1 --- Recognition performance of the database --- p.70 / Chapter 5.1.1 --- Definition of similarity --- p.70 / Chapter 5.1.2 --- Performance test of the recognition method --- p.70 / Chapter 5.1.2.1 --- Candidates in the library file --- p.70 / Chapter 5.1.2.2 --- Unknown not found in the library file --- p.75 / Chapter 5.1.3 --- Information drawn from the scores --- p.77 / Chapter 5.1.3.1 --- Recognition of the unknown sample in terms of similarity --- p.77 / Chapter 5.1.3.2 --- Relationship between the herbal drugs --- p.79 / Chapter 5.2 --- Applicability of the proposed methodology --- p.80 / Chapter 5.3 --- Limitation of the proposed methodology --- p.81 / Chapter 5.4 --- Future prospect --- p.81 / Chapter Chapter 6: --- Conclusion --- p.83 / References --- p.86 / Appendices / Chapter A. --- Linearity of calibration graphs using GC --- p.A1 / Chapter B. --- Linearity of calibration graphs using GC/MS --- p.A3 / Chapter C. --- GC/MS chromatograms of the herbal samples --- p.A5 / Chapter D. --- "Relative retention times of “effective"" and ""characteristic"" peaks" --- p.A28
629

Protein Separation with Ion-exchange Membrane Chromatography

Cao, Liming 04 May 2005 (has links)
Membrane chromatography is a promising process for the isolation, purification, and recovery of proteins, enzymes, and nuclear acids. Comparing with traditional beads column chromatography, membrane chromatography can faster, easier and cheaper to mass-produce. And also, it is easy to set up and scale up. In this thesis, we are trying to study the performance of membrane chromatography, and the mixture of HSA and chicken egg white is used as an example. We are investigating the purification of Human serum albumin (HSA) from chicken egg white in terms of precondition, dilution, purification method, product recovery, product purity and product cost. HSA, is a very important clinical protein. In order to obtain low cost, high efficiency and less risk HSA, recombinant DNA technology is used. Many kinds of host organism have been used to produce recombinant HSA (rHSA). In this thesis, a kind of ion-exchange membrane (Mustang Q membrane capsule) chromatography was used. The membrane capsule is disposable because it is designed for use in pharmaceutical production. For this project, a cleaning method was used which made the membrane capsule reusable. Washing with 4 mL 1 M NaCl and 4 mL NaOH was sufficient for this purpose. Since the egg white protein solution was very viscous, it needs to be diluted before loaded on FPLC. Dilute experiment was done to find the best dilution level. In this thesis, we found that 5 times dilution was best not only for high efficiency but also for FPLC operation. After getting the basic conditions, some purification experiments were done to find the optimal operation condition to purify HSA form chicken egg white protein solution by changing buffer pH, salt concentration in elution buffer and gradient used to elute proteins. The best purification condition for loading buffer is Tris-HCl buffer A (4.75g/L, pH 9.5) and the elution buffer is Tris-HCl buffer A + 0.2M NaCl. The purity of HSA recovered was 93% on the Mustang Q membrane capsule at 1 ml/min when the mixture of HSA and chicken egg white was diluted 10 times. And the yield was 85%. The impurity is probably ovoglobulin as suggested by the result of SDS-PAGE, whose molecular weight is close to 40kd. To characterize the separation capability of the Mustang Q membrane capsules, equilibrium adsorption and breakthrough curve studies were made using bovine serum albumin (BSA). 1mg/mL BSA solution was used to get the breakthrough curve with different flow rate ranging from 1 to 4 ml/min. With a flow rate is 1 ml/min, breakthrough curve were obtained with different concentrations of BSA ranging from 1 to 16 mg/mL. The dynamic binding capacity was found to be from 9.1 to 119.1 mg/mL. The equilibrium adsorption isotherm showed Langmuir isotherm behavior with dissociation constant and a maximum adsorption capability. According to the result of isotherm adsorption, a multi-plate mathematical model was used to get the theoretical breakthrough curve. By fitting the theoretical breakthrough curve to the experimental breakthrough curve, constants in the multi-plate model were obtained and were used to estimate the axial dispersion coefficient of the membrane capsule. The estimated axial dispersion coefficient of 2.45*10-6 cm2/s is very small which means that the axial ispersion is not significant. The adsorption process is therefore controlled by radial radius dispersion or film dispersion.
630

Desenvolvimento de método analítico para estudo de degradação forçada de cefalotina sódica na forma farmacêutica pó liofilizado para solução injetável /

Rugani, Karen de Souza. January 2015 (has links)
Orientador: Hérida Regina Nunes Salgado / Banca: Adriano Antunes de Souza Araújo / Banca: Anil Kumar Sing / Resumo: A cefalotina (CET) é um antimicrobiano β-lactâmico semi-sintético, bactericida e representa o protótipo das cefalosporinas, pertencente à classe da primeira geração. As cefalosporinas apresentam um espectro de atividade mais amplo do que as penicilinas e são amplamente prescritas. Poucos métodos analíticos são descritos na literatura para a análise de CET, e ao nosso conhecimento, nenhum método rápido e indicativo de estabilidade por cromatografia líquida para este composto foi publicado anteriormente. Foi desenvolvido um método indicativo de estabilidade por cromatografia líquida em fase reversa para determinação quantitativa de CET, na presença de impurezas e produtos de degradação gerados a partir dos estudos de degradação forçada em amostras de pó liofilizado para injeção. O método desenvolvido é também aplicável para a determinação de substâncias relacionadas em matéria-prima e em formas farmacêuticas. A separação cromatográfica foi obtida com a coluna Agilent Eclipse XDB-Phenyl, de 250 mm x 4,6 mm, 5 μm, em fase móvel composta por uma mistura das soluções A (tampão fosfato de amônio, pH 4,5) e B (acetonitrila), no modo de eluição gradiente. A vazão utilizada foi de 1,0 mL/min e o comprimento de onda 238 nm. O fármaco foi submetido a condições de estresse por hidrólise, oxidação, fotólise, umidade e degradação térmica. Obteve-se degradação considerável nas condições de hidrólise alcalina, ácida e estresse oxidativo. No método desenvolvido por cromatografia líquida de alta eficiência (CLAE), a resolução entre CET e os seus potenciais produtos de degradação foi maior que 2,4; além disso, a pureza de pico de CET em todas as condições foi maior que 99%, demonstrando o poder indicativo de estabilidade do método. A impureza B (desacetilcefalotina) que é um metabólito menos ativo da CET foi identificada e apresentou formação significativa, especialmente na condição... / Abstract: Cephalothin (CET) is a semi-synthetic β-lactam antimicrobial compound, bactericidal, and it represents the prototype of cephalosporins, which belongs to the first-generation class. Cephalosporins present a larger spectrum of activity than penicillins and they are widely prescribed. Few analytical methods are described in the literature for the analysis of CET and to our knowledge rapid stability-indicating liquid chromatography (LC) methods for this compound have not been published elsewhere. A stability-indicating gradient reversed phase liquid chromatography (RP-LC) method has been developed for the quantitative determination of CET, in the presence of its impurities and degradation products generated from forced degradation studies, in samples of lyophilized powder for injection. The developed method is also applicable for the related substances determination in bulk drugs and pharmaceutical forms. The chromatographic separation was achieved on an Agilent Eclipse XDB-Phenyl, 250 mm x 4.6 mm, 5 μm column with mobile phase containing a gradient mixture of solutions A (aqueous ammonium phosphate buffer, pH 4.5) and B (acetonitrile) as mobile phase. The flow rate was 1.0 mL/min and the detection wavelength was 238 nm. The drug substance was subjected to stress conditions of hydrolysis, oxidation, photolysis, humidity and thermal degradation. Considerable degradation was found to occur in base, acid and oxidative stress conditions. In the developed high performance liquid chromatography (HPLC) method, the resolution between CET and its potential degradation products was found to be greater than 2.4, further, the peak purity of CET in all conditions were more than 99% proving the stability-indicating power of method. The less active metabolite of CET, desacetylcephalothin (impurity B), was identified and is showed significant formation especially in alkaline condition. This method is able to detect the degradation products of CET at a ... / Mestre

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