Francisco Pena-Pereira (Ed.) Miniaturization in Sample Preparation Francisco Pena-Pereira (Ed.) Miniaturization in Sample Preparation Managing Editor: Anna Rulka Language Editor: Perry Mitchell Published by De Gruyter Open Ltd, Warsaw/Berlin Part of Walter de Gruyter GmbH, Berlin/Munich/Boston This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivs 3.0 license. © 2014 Francisco Pena-Pereira, published by De Gruyter Open ISBN: 978-3-11-041017-4 e-ISBN: 978-3-11-041018-1 Bibliographic information published by the Deutsche Nationalbibliothek. The Deutsche National- bibliothek lists this publication in the Deutsche Nationalbibliografie; detailed bibliographic data are available in the Internet at http://dnb.dnb.de. Managing Editor: Anna Rulka Language Editor: Perry Mitchell www.degruyteropen.com Cover illustration: © David Perez Parga & Francisco Pena-Pereira Contents List of Contributors    xii Francisco Pena-Pereira 1 From Conventional to Miniaturized Analytical Systems    1 1.1 Introduction    1 1.2 Miniaturizing Steps in the Analytical Process    3 1.2.1 A Need for Scaling Down Conventional Sample Preparation Techniques    9 1.2.2 Miniaturization of Analytical Separation    11 1.2.2.1 Gas Chromatography    12 1.2.2.2 Liquid Chromatography    14 1.2.2.3 Capillary Electrophoresis    16 1.2.3 Miniaturization of Detection Techniques    17 1.2.3.1 Molecular Spectrometry    18 1.2.3.2 Atomic Spectrometry    19 1.2.3.3 Mass Spectrometry    20 1.2.3.4 Electrochemical Techniques    21 1.3 Conclusions and Outlook    22 Abbreviations    23 Acknowledgements    24 References    24 Habib Bagheri, Hamed Piri-Moghadam, Mehrnoush Naderi, Ali Es’haghi and Ali Roostaie 2 Solid-Phase Microextraction and Related Techniques    29 2.1 Introduction    29 2.2 Solid-phase Microextraction Fundamentals    29 2.2.1 Principle of Solid-phase Microextraction    29 2.2.2 Different Modes of Solid-phase Microextraction    31 2.2.3 Coupling to Analytical Instrumentation    31 2.2.3.1 Off-line Coupling     31 2.2.3.2 On-line Coupling    31 2.2.3.2.1 On-line Coupling to Gas Chromatography    33 2.2.3.2.2 On-line Coupling to Liquid Chromatography    34 2.3 Extractant Phases in Solid-phase Microextraction    35 2.3.1 Conventional Extractant Phases    35 2.3.2 Extractant Phases Based on Inorganic Polymerization    37 2.3.2.1 Preparation of Sorbents by Sole Precursor    39 2.3.2.2 Preparation of Sorbents by Precursor and Coating Polymer    41 2.3.2.3 Preparation of Sorbents by Precursor and a Modifier    41 2.3.2.4 Chemical Bonding Between Substrates and Sorbent During Sol-Gel Process    42 2.3.2.4.1 Treatment of Fused Silica by NaOH    42 2.3.2.4.2 Self Assembled Monolayers    42 2.3.2.4.3 Diazonium Salts    43 2.3.3 Conductive Polymers    44 2.3.3.1 Structures of Some Well-known Conductive Polymers    47 2.3.3.2 Preparation of Conductive Polymers    48 2.3.3.2.1 Chemical Synthesis    49 2.3.3.2.2 Electrochemical Synthesis    49 2.3.3.3 Conductive Polymer-based Extractant Phases    51 2.3.3.3.1 Polypyrrole-based Coatings    51 2.3.3.3.2 Polyaniline-based Coatings    52 2.3.3.3.3 Polythiophene-based Coatings    53 2.3.4 Monolithic Polymers    54 2.3.4.1 Preparation of Monolithic Polymers    54 2.3.4.2 Monoliths for Solid-phase Microextraction    56 2.3.4.2.1 Fiber Format     56 2.3.4.2.2 In-tube Solid-phase Microextraction    57 2.3.5 Composites    58 2.3.5.1 Polymer Matrix Composites     59 2.3.5.2 Nanocomposite-based Coatings    61 2.3.6 Electrospun Nanofibers    63 2.3.7 Selective Sorbents    64 2.3.7.1 Molecularly Imprinted Polymers-based-solid-phase Microextraction    65 2.3.7.2 Molecularly Imprinted Xerogels-based-solid-phase Microextraction    65 2.3.8 Metal-based Coatings    67 2.3.8.1 Metal-based Fibers Preparation by Anodization     67 2.3.8.2 Metal-based Fibers Developed by Physical Coating    67 2.3.8.3 Metal-based Fibers Developed by Chemical Coating    68 2.4 Related Techniques    70 2.4.1 Microextraction in Packed Syringe    70 2.4.2 Stir Bar Sorptive Extraction    74 2.4.3 Needle Trap Extraction    75 2.5 Conclusions    76 Abbreviations    76 References    78 Bin Hu, Man He and Beibei Chen 3 Novel Materials in Solid-Phase Microextraction and Related Sample Preparation Approaches    88 3.1 Introduction    88 3.2 Coating Preparation Techniques Applied For Solid-phase Microextraction and Related Approaches    88 3.2.1 Sol-gel Technology    89 3.2.2 Physical Adhesion Method    89 3.2.3 Electrochemical Methods    90 3.2.3.1 Electrodeposition    90 3.2.3.2 Anodization    90 3.2.3.3 Electrophoretic Deposition    91 3.2.4 Polymerization     91 3.2.5 Chemical Vapor Deposition    92 3.2.6 Liquid Phase Deposition    92 3.3 Commercial Solid-phase Microextraction Coatings    92 3.4 Novel Materials for Solid-phase Microextraction and Related Approaches    94 3.4.1 Nanostructured Materials    94 3.4.1.1 Carbon Nanomaterials    95 3.4.1.2 Metal Oxide Nanomaterials    99 3.4.1.3 Mesoporous Materials    101 3.4.1.4 Application of Nanomaterials in Solid-Phase Microextraction and Related Approaches    105 3.4.2 Molecularly Imprinted Materials    105 3.4.3 Ionic Liquid Coatings    122 3.4.4 Immunosorbents    125 3.4.5 Metal-organic Frameworks    131 3.5 Other Novel Materials    139 3.5.1 Monolithic Materials    139 3.5.2 Restricted Access Materials    142 3.6 Application of Various Materials in Solid-phase Microextraction-related Approaches    144 3.7 Conclusions and Prospects    157 Abbreviations    157 Acknowledgements    162 References    162 Elena Fernández and Lorena Vidal 4 Liquid-phase Microextraction Techniques    191 4.1 Introduction    191 4.1.1 History    191 4.1.2 Solvents    195 4.1.3 Separation and Detection Systems    197 4.1.4 Energy and Radiation    200 4.1.5 Optimization Strategies    200 4.2 Single-drop Microextraction    201 4.2.1 Headspace Single-drop Microextraction    203 4.2.2 Direct Immersion    205 4.2.2.1 Direct Immersion Single-drop Microextraction    205 4.2.2.2 Drop-in-drop and Drop-to-drop    207 4.2.2.3 Continuous Flow Microextraction    209 4.2.2.4 Liquid-liquid-liquid Microextraction    210 4.2.2.5 Directly Suspended Droplet Microextraction    212 4.2.2.6 Solidification of Floating Organic Drop Microextraction    214 4.3 Membrane-based Liquid-phase Microextraction    215 4.3.1 Hollow Fiber Liquid-phase Microextraction    215 4.3.2 Electromembrane Extraction    220 4.4 Dispersive Liquid-liquid Microextraction    225 4.4.1 Classical Dispersive Liquid-liquid Microextraction    225 4.4.2 Ultrasound- and Vortex-assisted Dispersive Liquid-liquid Microextraction    230 4.4.3 Temperature-assisted Dispersive Liquid-liquid Microextraction    231 4.4.4 In Situ Ionic Liquid Formation Dispersive Liquid-liquid Microextraction    231 4.4.5 Supramolecular-based Dispersive Liquid-liquid Microextraction    232 4.4.6 Air-assisted Liquid-liquid Microextraction    234 4.5 Conclusions    234 Abbreviations    235 Acknowledgements    237 References    237 Shayessteh Dadfarnia and Ali Mohammad Haji-Shabani 5 Choice of Solvent in Liquid-Phase Microextraction    253 5.1 Introduction    253 5.2 Relevance of Physicochemical Properties in Extractant Phase Selection    253 5.2.1 Solubility    253 5.2.2 Distribution Coefficient    254 5.2.3 Selectivity    254 5.2.4 Immiscibility    258 5.2.5 Density    258 5.2.6 Interfacial Tension    259 5.2.7 Chemical Reactivity    259 5.2.8 Corrosiveness    259 5.2.9 Viscosity, Boiling Point and Vapor Pressure    259 5.2.10 Availability and Cost    260 5.2.11 Other Criteria    260 5.3 Extracting Solvents for Liquid-phase Microextraction    260 5.3.1 Extractant Phases for Single-drop Microextraction    261 5.3.2 Extractant Phases for Directly-suspended Droplet Microextraction    264 5.3.3 Extractant Phases for Hollow Fiber Liquid-phase Microextraction    266 5.3.4 Extractant Phases for Dispersive Liquid-liquid Microextraction    268 5.4 Conclusions    271 Abbreviations    272 References    273 Marta Costas-Rodriguez and Francisco Pena-Pereira 6 Method Development with Miniaturized Sample Preparation Techniques    276 6.1 Introduction    276 6.2 Evaluation of Experimental Parameters    277 6.2.1 Type of Miniaturized Sample Preparation Technique    278 6.2.2 Type of Extractant Phase    279 6.2.3 Sample and Extractant Phase Volumes    280 6.2.4 Extraction Time    282 6.2.5 Agitation of the Sample    284 6.2.6 pH    285 6.2.7 Ionic Strength    285 6.2.8 Temperature    287 6.2.9 Derivatization    287 6.2.10 Desorption    289 6.3 Optimization Strategies For Analytical Method Development    290 6.3.1 Screening of the Variables    292 6.3.2 Optimization    293 6.4 Validation of Microextraction Methodologies    298 6.5 Conclusions    300 Abbreviations    300 Acknowledgements    302 References    302 Noelia Cabaleiro and Inmaculada de la Calle 7 Miniaturized Alternatives to Conventional Sample Preparation Techniques for Solid Samples    308 7.1 Introduction    308