Biomedical Engineering Reference
In-Depth Information
10
The Challenge of Human Skin—Engineering the
Biotic/Abiotic Interface
Puneet Khanna, Steven Hoath, Rod Smallwood, and Shekhar Bhansali
CONTENTS
10.1 Introduction ......................................................................................................................250
10.2 Skin-Interface Systems: Concept ..................................................................................251
10.3 Anatomy of Skin ..............................................................................................................252
10.3.1 General Structure ..............................................................................................252
10.3.2 Stratum Corneum ..............................................................................................253
10.4 System Architecture ........................................................................................................254
10.5 Design of the System ......................................................................................................256
10.6 Significance of Skin-Interface Systems ........................................................................256
10.6.1 Bioimpedance and Bioelectricity Measurement ..........................................257
10.6.2 Electrochemical Sensing ..................................................................................257
10.6.3 Programmed Drug Delivery ............................................................................257
10.6.4 Automated Feedback-Controlled Therapy ....................................................258
10.6.5 Electrotherapeutic Pain Relief ........................................................................258
10.6.6 Iontophoresis ......................................................................................................258
10.7 Technological Merit of Skin-Interface Systems ..........................................................258
10.7.1 Benefits from Microelectrodes ........................................................................259
10.7.2 Benefits from Microneedles ............................................................................260
10.8 Designing the Interface Microtools ..............................................................................262
10.8.1 Functional Requirements or Constraints ......................................................262
10.8.1.1 Electrical Parameters ........................................................................262
10.8.1.2 Mechanical Parameters ....................................................................263
10.8.1.3 Other Parameters ..............................................................................263
10.8.2 Design Variables ................................................................................................263
10.8.2.1 Material Selection ............................................................................263
10.8.2.2 Geometrical Considerations ............................................................264
10.8.2.3 Array Layout ....................................................................................264
10.9 Evaluation of Microstructure Interaction with Skin ..................................................265
10.9.1 Microneedle Testing ..........................................................................................265
10.9.2 Microelectrode Testing ......................................................................................266
10.10 Conclusion ........................................................................................................................266
References ....................................................................................................................................267
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