Preface CHAPTER 1 – Introduction & Literature review 1.1 Drug delivery through the skin 1.2 Skin as a route for drug delivery: anatomy and challenges 1.3 Literature Review 1.3.1 Drug delivery systems 1.3.2 Routes of drug delivery 1.3.3 Mechanisms of drug absorption through skin 1.3.4 Microneedles as a method of drug delivery through the skin 1.3.5 Microneedles: development and current status 1.3.6 Testing of drug penetration through the skin 1.3.7 Static diffusion cells CHAPTER 2 – Materials & Methods 2.1 Materials 2.2 A simple method of making microneedle patches for drug delivery through the skin 2.2.1 Coating of glass coverslips 2.2.2 Making of microneedle backing layers 2.2.3 Making microneedle shafts 2.2.4 Microneedle insertion in pig skin 2.2.5 Encapsulation of a sample drug and testing 2.2.6 Drug penetration through rat skin following the use of microneedle 2.3 Protein encapsulation in microneedles by photolithography 2.3.1 Making and characterization of polymeric microneedles 2.3.2 Incorporation and protein distribution in microneedles 2.3.3 Stability tests for protein in microneedles 2.3.4 Release of protein from microneedles 2.3.5 Protein penetration through rat skin 2.3.6 Testing of toxicity of coated microneedles to human cells 2.4 Microneedle skin patch for fast onset and long-lasting delivery of painkillers 2.4.1 Making microneedle skin patch 2.4.2 Drug encapsulation in microneedle skin patch 2.4.3 Mechanical strength of microneedles 2.4.4 Test of painkiller release from microneedles 2.4.5 Painkiller penetration through rat skin 2.4.6 Measurement of painkiller concentration 2.4.7 Interaction between microneedle material and painkiller 2.5 Using microneedle patch to deliver collagen through the skin 2.5.1 Making photomask with embedded microlenses 2.5.2 Making microneedle shafts 2.5.3 Making microneedle backing layer 2.5.4 Microneedle fracture force testing 2.5.5 Sharp microneedle penetration in the skin 2.5.6 Collagen penetration through skin CHAPTER 3 - A Simple Method of Microneedle Array Fabrication for Transdermal Drug Delivery 3.1 Overview 3.2 Results 3.2.1 Effect of UV light on microneedles 3.2.2 Effect of spacer thickness on microneedles 3.2.3 Microneedle penetration in pig skin 3.2.4 Encapsulation in and drug release from microneedles 3.2.5 Drug penetration through rat skin 3.3 Discussion 3.4 Summary CHAPTER 4 - Protein Encapsulation in Polymeric Microneedles by Photolithography 4.1 Overview 4.2 Results 4.2.1 Formation and characterization of microneedles 4.2.2 Incorporation and uniform drug distribution in microneedles 4.2.3 Stability tests for protein in microneedles 4.2.4 Release of protein from microneedles 4.2.5 Drug penetration through rat skin 4.2.6 Compatibility of microneedles with living tissues 4.3 Discussion 4.4 Summary CHAPTER 5 - Microneedle Patch for Fast Onset and Long-lasting Delivery of Painkillers 5.1 Overview 5.2 Results 5.2.1 Geometric properties of microneedle patch 5.2.2 Drug encapsulation in microneedle patch 5.2.3 Mechanical strength of microneedle patch 5.2.4 Painkiller release from microneedle patch 5.2.5 Painkiller penetration through the skin 5.2.6 Interaction between microneedle material and drug 5.3 Discussion 5.4 Summary CHAPTER 6 - Microneedle Patch to Deliver Collagen through the Skin 6.1 Overview 6.2 Results 6.2.1 Manufacturing of photomask 6.2.2 Manufacturing of polymer-coated microneedles 6.2.3 Effect of microneedle backing layer volume 6.2.4 Microneedle fracture force testing 6.2.5 Microneedle penetration in human skin 6.2.6 Collagen penetration through rat skin 6.3 Discussion 6.4 Summary CHAPTER 7 - Recent trends in microneedle development & applications in medicine & cosmetics (2013-2018) 7.1 Therapeutics 7.1.1 Protein drugs 7.1.2 Vaccines 7.1.3 Small molecule drugs 7.1.4 Microneedle designs for transdermal drug delivery 7.1.5 Materials for microneedle fabrication used for transdermal delivery of therapeutic agents 7.1.6 Conclusion for the microneedle delivery of therapeutic agents 7.2 Cosmetics 7.2.1 Cosmeceutical agents delivered by microneedles and their cosmetic benefits 7.2.2 Types of microneedle devices in cosmeceutical application CHAPTER 8 – Conclusions & Future Directions 8.1 Conclusions 8.2 Future Directions Index
This monograph covers a novel technology to deliver drugs and cosmetics through the skin in a minimally invasive manner. Microneedles – a bed of miniaturized needles is one of the most studied topics in delivering actives through the skin barrier. This book enables readers to understand the delivery of ingredients through the skin, describes a novel and simple method to fabricate microneedles containing a range of small and large molecular weight compounds, studies their physical properties as well as delivery through the skin layers.
Readers will discover this book to be extremely beneficial to help them understand the state of the field of transdermal drug delivery, with extensive coverage including experimental data on basics of microneedle fabrication technology using photolithography, encapsulation of drugs within the polymeric matrix of microneedles and studying their release patternsin vitro and ex vivo . Academic researchers, pharmaceutical and cosmeceutical industry as well as students of skin science will find this account very useful in their pursuits. As microneedles grow and develop into a commercial reality with more actives being delivered and significant clinical research being put in, this account will hold well in providing basic principles and knowledge together with rigorous experimental data.