Sustained Release Solid Lipid Nanoparticles Formulation of Lumefantrine and Ciprofloxacin

Title Page --- --- --- --- --- --- --- --- --- --- i

Certification --- --- --- --- --- --- --- --- --- --- ii

Dedication --- --- --- --- --- --- --- --- --- --- --- iii

Acknowledgment --- --- --- --- --- --- --- --- --- --- iv

Table of contents --- --- --- --- --- --- --- --- --- --- vi

Abstract --- --- --- --- --- --- --- --- --- --- --- xii

List of tables--- --- --- --- --- --- --- --- --- --- xvii

List of figures--- --- --- --- --- --- --- --- --- ---

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CHAPTER ONE: INTRODUCTION --- --- --- --- --- --- --- 1

1.0 General introduction --- --- --- --- --- --- --- --- 1

1.1 Drug delivery systems--- --- --- --- --- --- --- --- 3

1.2 Various colloidal systems--- --- --- --- --- --- --- --- 4

1.2.1 Liposomes --- --- --- --- --- --- --- --- --- 4

1.2.2 Niosomes --- --- --- --- --- --- --- --- --- --- 5

1.2.3 Solid lipid microparticles (SLMs) --- --- --- --- --- --- 6

1.2.4 Microemulsions --- --- --- --- --- --- --- --- --- 6

1.2.5 Self emulsifying delivery system (SEDD) ------ --- --- --- --- 7

1.2.6 Overview of solid lipid nanoparticles (SLNs) --- --- --- --- --- 8

1.2.6.1 Advantages of SLNs --- --- --- --- --- --- --- --- 9

1.2.6.2 Disadvantages of SLNs --- --- --- --- --- --- --- --- 10

1.2.7 Sustained release formulation --- --- --- --- --- --- --- 11

1.2.7.1 Rationale of formulating sustained release carrier system --- --- --- 12

1.2.7. 2 Advantages of sustained release formulation --- --- --- --- 12

1.3 Materials used in the preparation of SLNs --- --- --- --- --- --- 13

1.3.1 Surfactants --- --- --- --- --- --- --- --- --- --- 13

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1.3.1.1 Classification of surfactants --- --- --- --- --- --- --- 14

1.3.1.2 Cationic surfactants --- --- --- --- --- --- --- --- 15

1.3.1.3 Anionic surfactants --- --- --- --- --- --- --- --- 15

1.3.1.4 Non –ionic surfactants --- --- --- --- --- --- --- --- 16

1.3.1.5 Amphoteric surfactants --- --- --- --- --- --- --- --- 17

1.3.1.6 Hydrophile- lipophile balance value --- --- --- --- --- --- 17

1.3.2 Lipids --- --- --- --- --- --- --- --- --- --- 19

1.3.2.1 Classification of lipids --- --- --- --- --- --- --- --- 20

1.3.2.2 Lipid digestion --- --- --- --- --- --- --- --- --- 23

1.3.3 .1 Polysorbate 80/Tween 80 ---- --- --- --- --- --- --- 28

1.3.3.2 Solutol HS 15 --- --- --- --- --- --- --- --- --- 29

1.3.3.3 Poloxamer 188 --- --- --- --- --- --- --- --- --- 30

1.3.4 Precirol ATO --- --- --- --- --- --- --- --- --- 31

1.3.5. Transcutol HP --- --- --- --- --- --- --- --- --- 32

1.3.6 Tallow fat --- --- --- --- --- --- --- --- --- --- 33

1.4 Techniques in formulation of SLNs --- --- --- --- --- --- --- 35

1.4.1 High pressure homogenization --- --- --- --- --- --- --- 35

1.4.1.1 Hot homogenization --- --- --- --- --- --- --- --- 35

1.4.1.2 Cold homogenization --- --- --- --- --- --- --- --- 36

1.4.2.Solvent emulsification diffusion technique --- --- --- --- --- 36

1.4.3 Microemulsion technique --- --- --- --- --- --- --- --- 37

1.4.4 Solvent evaporation technique --- --- --- --- --- --- --- 37

1.4.5 Spray drying method ------ --- --- --- --- --- --- --- 37

1.4.6 Ultrasonication//high speed homogenication --- --- --- --- --- 38

1.4.7 Double emulsion method --- --- --- --- --- --- --- --- 38

1.4.8 W/O/W Double emulsion method --- --- --- --- --- --- --- 38

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1.5 Overview of drugs used in the formulation --- --- --- --- --- --- 38

1.5.1 Lumefnatrine ------ --- --- --- --- --- --- --- --- 38

1.5.1 1 Chemistry --- --- --- --- --- --- --- --- --- --- 39

1.5.1.2 Mechanism of action --- --- --- --- --- --- --- --- 39

1.5.1.3 Pharmacokinetics --- --- --- --- --- --- --- --- --- 39

1.5.1.4 Toxicity --- --- --- --- --- --- --- --- --- --- 40

1.5.2 Ciprofloxacin --- --- --- --- --- --- --- --- --- 40

1.5.2 1 Chemistry --- --- --- --- --- --- --- --- --- --- 41

1.5.2.2 Mechanism of action --- --- --- --- --- --- --- --- 41

1.5.2.3 Pharmacokinetics --- --- --- --- --- --- --- --- --- 41

1.5.2.4 Toxicity --- --- --- --- --- --- --- --- --- --- 42

1.5.3 Artemether --- --- --- --- --- --- --- --- --- --- 42

1.5.3.1 Chemistry --- --- --- --- --- --- --- --- --- --- 44

1.5.3.2 Pharmacokinetics --- --- --- --- --- --- --- --- --- 44

1.5.3.3 Toxicity --- --- --- --- --- --- --- --- --- --- 45

1.5.3.4 Mechanism of action --- --- --- --- --- --- --- --- 45

1.5.4 Artemether and lumefantrine (AL) combination --- --- --- --- --- 45

1.6 Justification of study --- --- --- --- --- --- --- --- --- 47

1.6.1 Aim of study --- --- --- --- --- --- --- --- --- 48

1.6.3 Objectives --- --- --- --- --- --- --- --- --- --- 49

1.6.4 Literature review --- --- --- --- --- --- --- --- --- 49

CHAPTER TWO: MATERIALS AND METHODS--- --- --- --- --- 55

2.1 Materials --- --- --- --- --- --- --- --- --- --- 55

2.1.1 Animals --- --- --- --- --- --- --- --- --- --- 56

2.2 Methods --- --- --- --- --- --- --- --- --- --- 57

2.2.1 Preliminary studies --- --- --- --- --- --- --- --- --- 57

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2.2.2 Lipid selection by differential scanning calorimetry (DSC) and formulation of

 lipid matrix --- --- --- --- --- --- --- --- --- --- 57

2.2.3 Differential scanning calorimetry (DSC) --- --- --- --- --- --- 57

2.2.4 formulation of lipid SLNS --- --- --- --- --- --- --- --- 58

2.2.4.1 General procedure for formulation of SLNs containing Precirol + Transcutol

 and Tallow fat + Transcutol --- --- --- --- --- --- --- 58

2.2.4.2 General procedure for formulation of SLNs --- --- --- --- --- 58

2.2.5 Preparation of simulated gastric fluid (SGF) --- --- --- --- --- 60

2.2.6 Preparation of simulated intestine fluid (SIF) --- --- --- --- --- 60

2.2.7 Preparation of 0.1M methanolic HCl --- --- --- --- --- --- 60

2.3 Characterization of SLNs --- --- --- --- --- --- --- --- 60

2 .3.1 Determination of percentage yield --- --- --- --- --- --- --- 60

2.3.2 Particle size and morphology --- --- --- --- --- --- --- 61

2.3.2.1 Particle morphology --- --- --- --- --- --- --- --- 61

2.3.2.2 Particle size and polydispersity index --- --- --- --- --- --- 61

2.3.2.3 Zeta potential analysis --- --- --- --- --- --- --- --- 61

2.4 Degree of crystallinity and polymorphism --- --- --- --- --- --- 62

2.5 Determination of entrapment efficiency of SLNs --- --- --- --- --- 62

2.5.1 Determination of absorption maxima for lumefantrine --- --- --- --- 62

2.5.2 Calibration curve of lumefantrine in 0.1M methanolic HCl --- --- --- 63

2.5.3 Determination of absorbance maxima for ciprofloxacin in 0.1 N HCl (pH 1.2) --- 63

2.5.4 Calibration curve for ciprofloxacin --- --- --- --- --- --- 63

2.6 pH –dependent stability studies of the formulations --- --- --- --- --- 63

2.7 Fourier transform infra red spectroscopy (FT-IR) --- --- --- --- --- 64

2.8 Formulation of liquisolid compacts ( SLNs based tablets of artemether –lumefantrine) 64

2.8.1 Weight uniformity test --- --- --- --- --- --- --- --- 64

2.8.2 Tablet friability test --- --- --- --- --- --- --- --- --- 65

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2.8.3 Hardness test --- --- --- --- --- --- --- --- --- 65

2.8.4 Disintegration time test --- --- --- --- --- --- --- --- 65

2.8.5 Absolute drug content (assay of artemether) --- --- --- --- --- 65

2.8.5.1 Preparation of standard solution --- --- --- --- --- --- --- 65

2.8.5.2 Determination of absorption maxima for artemether (in distilled water) --- 66

2.8.5.3 Calibration curve of artemether --- --- --- --- --- --- --- 66

2.8.5.4 Assay of artemether in liquisolid compacts /tablets ---- --- --- --- 66

2.8.5.5.5 Dissolution rate test --- --- --- --- --- --- --- --- 67

2.9 In-vitro dissolution studies --- --- --- --- --- --- --- --- 67

2.9.1 In-vitro release of ciprofloxacin loaded SLNs --- --- --- --- --- 67

2.9.2 Drug release study of ciprofloxacin as a function of inhibition zone (IZD ---

68

2.9.3 In-vitro release of lumefantrine and artemether --- --- --- --- --- 68

2.10 In-vivo schizontocidal activity test --- --- --- --- --- --- 69

2.11 Data and statistical analysis --- --- --- --- --- --- --- ---

70

CHAPTER THREE: RESULTS AND DISCUSSION --- ---- --- --- 71

3.1 Characterization of lipid matrices --- --- --- --- --- --- --- 71

3.2 Percentage yield --- --- --- --- --- --- --- --- --- 83

3.3 Differential scanning calorimetry (DSC)for the formulated SLN --- --- 86

3.4 pH- dependent stability studies --- --- --- --- --- --- --- 98

3.5 Morphology and particle size distribution --- --- --- --- --- --- 101

3.6 Encapsulation efficiency --- --- --- --- --- --- --- --- 114

3.7 Tablet properties --- --- --- --- --- --- --- --- --- 116

3.8 Antimicrobial studies of ciprofloxacin --- --- --- --- --- --- 119

3.9 In vitro drug release profile of SLNs loaded ciprofloxacin and SLN lumefantrine

 based artemether tablets --- --- --- --- --- --- --- --- 122

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3.9.1 In vitro dissolution of lumefantrine --- --- --- --- --- --- --- 122

3.9.2 In vitro dissolution of artemether --- --- --- --- --- --- --- 125

3.9.3 In vitro dissolution of ciprofloxacin --- --- --- --- --- --- 126

3.10 Evaluation of drug release mechanism and kinetics ------ --- --- --- 128

3.11 FT-IR Analysis Results --- --- --- --- --- --- --- --- 131

3.12 In vivo Schizontocidal activity --- --- --- --- --- --- --- 139

CHAPTER FOUR: SUMMARY AND CONCLUSION --- --- --- --- 149

4.1 Summary --- --- --- --- --- --- --- --- --- --- 149

4.2 Conclusion --- --- --- --- --- --- --- --- --- --- 153

4.3 Recommendation (Contribution to Knowledge) --- --- --- --- --- 153

REFERENCES --- --- --- --- --- --- --- --- --- 154

APPENDICES --- --- --- --- --- --- --- --- --- 171