This overview aims to summarize the existing potential of “ Ionogels” as a platform to develop stimuli responsive materials. Ionogels are a class of materials that contain an Ionic Liquid (IL) confined within a polymer matrix. Recently defined as “a solid interconnected network spreading throughout a liquid phase”, the ionogel therefore combines the properties of both its solid and liquid components. ILs are low melting salts that exist as liquids composed entirely of cations and anions at or around 100 °C. Important physical properties of these liquids such as viscosity, density, melting point and conductivity can be altered to suit a purpose by choice of the cation/anion. Here we provide an overview to highlight the literature thus far, detailing the encapsulation of IL and responsive materials within these polymeric structures. Exciting applications in the areas of optical and electrochemical sensing, solid state electrolytes and actuating materials shall be discussed.
References
[1]
Diamond, D.; Coyle, S.; Scarmagnani, S.; Hayes, J. Wireless sensor networks and chemo-/biosensing. Chem. Rev. 2008, 108, 652–679, doi:10.1021/cr0681187.
[2]
Bobacka, J.; Ivaska, A.; Lewenstam, A. Potentiometric ion sensors based on conducting polymers. Electroanal 2003, 15, 366–374, doi:10.1002/elan.200390042.
[3]
Singh, N.; Mulrooney, R.C.; Kaur, N.; Callan, J.F. A nanoparticle based chromogenic chemosensor for the simultaneous detection of multiple analytes. Chem. Commun. 2008, 4900–4902.
[4]
Schmittel, M.; Lin, H.W. Quadruple-channel sensing: A molecular sensor with a single type of receptor site for selective and quantitative multi-ion analysis. Angew. Chem.-Inter. Ed. 2007, 46, 893–896, doi:10.1002/anie.200603362.
[5]
Bakker, E.; Diamond, D.; Lewenstam, A.; Pretsch, E. Ion sensors: Current limits and new trends. Anal. Chim. Acta 1999, 393, 11–18, doi:10.1016/S0003-2670(99)00056-2.
[6]
Diamond, D. Internet-scale sensing. Anal. Chem. 2004, 76, 278–286, doi:10.1021/ac041598m.
[7]
Park, C.O.; Fergus, J.W.; Miura, N.; Park, J.; Choi, A. Solid-state electrochemical gas sensors. Ionics 2009, 15, 261–284, doi:10.1007/s11581-008-0300-6.
[8]
Anastasova-Ivanova, S.; Mattinen, U.; Radu, A.; Bobacka, J.; Lewenstam, A.; Migdalski, J.; Danielewskic, M.; Diamond, D. Development of miniature all-solid-state potentiometric sensing system. Sensor. Actuator. B-Chem. 2010, 146, 199–205, doi:10.1016/j.snb.2010.02.044.
[9]
Ahn, S.-K.; Kasi, R.M.; Kim, S.-C.; Sharma, N.; Zhou, Y. Stimuli-responsive polymer gels. Soft Matter 2008, 4, 1151–1157, doi:10.1039/b714376a.
[10]
Osada, Y.; Gong, J.P. Soft and wet materials: Polymer gels. Adv. Mater 1998, 10, 827–837, doi:10.1002/(SICI)1521-4095(199808)10:11<827::AID-ADMA827>3.0.CO;2-L.
[11]
Neouze, M.A.; Le Bideau, J.; Gaveau, P.; Bellayer, S.; Vioux, A. Ionogels, new materials arising from the confinement of ionic liquids within silica-derived networks. Chem. Mater 2006, 18, 3931–3936, doi:10.1021/cm060656c.
[12]
Susan, M.A.; Kaneko, T.; Noda, A.; Watanabe, M. Ion gels prepared by in situ radical polymerization of vinyl monomers in an ionic liquid and their characterization as polymer electrolytes. J. Am. Chem. Soc. 2005, 127, 4976–4983, doi:10.1021/ja045155b. 15796564
[13]
Le Bideau, J.; Viau, L.; Vioux, A. Ionogels, ionic liquid based hybrid materials. Chem. Soc. Rev. 2011, 40, 907–925, doi:10.1039/c0cs00059k.
[14]
Ueki, T.; Watanabe, M. Macromolecules in ionic liquids: Progress, challenges, and opportunities. Macromolecules 2008, 41, 3739–3749, doi:10.1021/ma800171k.
[15]
Kavanagh, A.; Byrne, R.; Diamond, D.; Radu, A. A two-component polymeric optode membrane based on a multifunctional ionic liquid. Analyst 2011, 136, 348–353, doi:10.1039/c0an00770f.
[16]
Kavanagh, A.; Hilder, M.; Clark, N.; Radu, A.; Diamond, D. Wireless radio frequency detection of greatly simplified polymeric membranes based on a multifunctional ionic liquid. Electrochim. Acta 2011, 56, 8947–8953, doi:10.1016/j.electacta.2011.07.121.
[17]
Kavanagh, A.; Copperwhite, R.; Oubaha, M.; Owens, J.; McDonagh, C.; Diamond, D.; Byrne, R. Photo-patternable hybrid ionogels for electrochromic applications. J. Mater Chem. 2011, 21, 8687–8693, doi:10.1039/c1jm10704f.
[18]
Benito-Lopez, F.; Byrne, R.; Raduta, A.M.; Vrana, N.E.; McGuinness, G.; Diamond, D. Ionogel-based light-actuated valves for controlling liquid flow in micro-fluidic manifolds. Lab Chip 2010, 10, 195–201, doi:10.1039/b914709h.
Khodagholy, D.; Curto, V.F.; Fraser, K.J.; Gurfinkel, M.; Byrne, R.; Diamond, D.; Benito-Lopez, F.; Owens, R.M. Organic electrochemical transistor incorporating an ionogel as solid state electolyte for lactate sensing. J. Mater. Chem. 2011, doi:10.1039/C2JM15716K.
[21]
Welton, T. Room-temperature ionic liquids. Solvents for synthesis and catalysis. Chem. Rev. 1999, 99, 2071–2083, doi:10.1021/cr980032t.
[22]
Fraser, K.J.; MacFarlane, D.R. Phosphonium-based ionic liquids: An overview. Aust. J. Chem. 2009, 62, 309–321, doi:10.1071/CH08558.
[23]
Zhao, C.; Burrell, G.; Torriero, A.A.J.; Separovic, F.; Dunlop, N.F.; MacFarlane, D.R.; Bond, A.M. Electrochemistry of room temperature protic ionic liquids. J. Phys. Chem. B 2008, 112, 6923–6936, doi:10.1021/jp711804j. 18489145
[24]
Plechkova, N.V.; Seddon, K.R. Applications of ionic liquids in the chemical industry. Chem. Soc. Rev. 2008, 37, 123–150, doi:10.1039/b006677j.
[25]
Xue, H.; Gao, Y.; Twamley, B.; Shreeve, J.M. New energetic salts based on nitrogen-containing heterocycles. Chem. Mater. 2005, 17, 191–198, doi:10.1021/cm048864x.
[26]
MacFarlane, D.R.; Forsyth, M.; Izgorodina, E.I.; Abbott, A.P.; Annat, G.; Fraser, K. On the concept of ionicity in ionic liquids. Pccp. Phys. Chem. Chem. Phys. 2009, 11, 4962–4967, doi:10.1039/b900201d.
Ermolaev, V.; Miluykov, V.; Rizvanov, I.; Krivolapov, D.; Zvereva, E.; Katsyuba, S.; Sinyashin, O.; Schmutzler, R. Phosphonium ionic liquids based on bulky phosphines: Synthesis, structure and properties. Dalton Trans. 2010, 39, 5564–5571, doi:10.1039/b924636c. 20480083
[29]
Busi, S.; Lahtinen, M.; Mansikkamaki, H.; Valkonen, J.; Rissanen, K. Synthesis, characterization and thermal properties of small R2R’2N+X- type quaternary ammonium halides. J. Solid State Chem. 2005, 178, 1722–1737, doi:10.1016/j.jssc.2005.03.008.
[30]
MacFarlane, D.R.; Golding, J.; Forsyth, S.; Forsyth, M.; Deacon, G.B. Low viscosity ionic liquids based on organic salts of the dicyanamide anion. Chem. Commun. 2001, 1430–1431.
[31]
MacFarlane, D.R.; Pringle, J.M.; Johansson, K.M.; Forsyth, S.A.; Forsyth, M. Lewis base ionic liquids. Chem. Commun. 2006, 1905–1917.
[32]
Ercole, F.; Davis, T.P.; Evans, R.A. Photo-responsive systems and biomaterials: photochromic polymers, light-triggered self-assembly, surface modification, fluorescence modulation and beyond. Polym. Chem. 2010, 1, 37–54, doi:10.1039/b9py00300b.
[33]
Mortimer, R.J. Electrochromic materials. In Annual Review of Materials Research; Clarke, D.R.F.P., Ed.; Annual Reviews: Palo Alto, CA, USA, 2011; Volume 41, pp. 241–268.
[34]
Zhang, H.X.; Meng, X.; Li, P. Light and thermal-stimuli responsive materials. Prog. Chem. 2008, 20, 657–672.
[35]
Einaga, Y. Photo-switching magnetic materials. J. Photochem. Photobiol. C-Photo 2006, 7, 69–88, doi:10.1016/j.jphotochemrev.2006.05.001.
Scarmagnani, S.; Walsh, Z.; Slater, C.; Alhashimy, N.; Paull, B.; Macka, M.; Diamond, D. Polystyrene bead-based system for optical sensing using spiropyran photoswitches. J. Mater Chem. 2008, 18, 5063–5071, doi:10.1039/b810080b.
[38]
Stitzel, S.; Byrne, R.; Diamond, D. LED switching of spiropyran-doped polymer films. J. Mater Sci. 2006, 41, 5841–5844, doi:10.1007/s10853-006-0289-z.
[39]
Radu, A.; Byrne, R.; Alhashimy, N.; Fusaro, M.; Scarmagnani, S.; Diamond, D. Spiropyran-based reversible, light-modulated sensing with reduced photofatigue. J. Photochem. Photobiol. A-Chem. 2009, 206, 109–115, doi:10.1016/j.jphotochem.2009.05.022.
[40]
Earle, M.J.; Gordon, C.M.; Plechkova, N.V.; Seddon, K.R.; Welton, T. Decolorization of ionic liquids for spectroscopy. Anal. Chem. 2007, 79, 758, doi:10.1021/ac061481t.
[41]
Miljanic, S.; Frkanec, L.; Meic, Z.; Zinic, M. Photoinduced gelation by stilbene oxalyl amide compounds. Langmuir 2005, 21, 2754–2760, doi:10.1021/la047183d.
[42]
Sanchez, A.M.; Barra, M.; de Rossi, R.H. On the mechanism of the acid/base-catalyzed thermal cis-trans isomerization of methyl orange. J. Org. Chem. 1999, 64, 1604–1609, doi:10.1021/jo982069j.
[43]
Bazarnik, M.; Henzl, J.; Czajka, R.; Morgenstern, K. Light driven reactions of single physisorbed azobenzenes. Chem. Commun. 2011, 47, 7764–7766, doi:10.1039/c1cc11578b.
[44]
Ichimura, K.; Oh, S.K.; Nakagawa, M. Light-driven motion of liquids on a photoresponsive surface. Science 2000, 288, 1624–1626, doi:10.1126/science.288.5471.1624.
[45]
Hanabusa, K.; Hiratsuka, K.; Kimura, M.; Shirai, H. Easy preparation and useful character of organogel electrolytes based on low molecular weight gelator. Chem. Mater. 1999, 11, 649–655, doi:10.1021/cm980528r.
[46]
Terech, P.; Weiss, R.G. Low molecular mass gelators of organic liquids and the properties of their gels. Chem. Rev. 1997, 97, 3133–3159, doi:10.1021/cr9700282.
[47]
Murata, K.; Aoki, M.; Suzuki, T.; Harada, T.; Kawabata, H.; Komori, T.; Ohseto, F.; Ueda, K.; Shinkai, S. Thermal and light control of the sol-gel phase transition in cholesterol-based organic gels. Novel helical aggregation modes as detected by circular dichroism and electron microscopic observation. J. Am. Chem. Soc. 1994, 116, 6664–6676, doi:10.1021/ja00094a023.
Radu, A.; Scarmagnani, S.; Byrne, R.; Slater, C.; Lau, K.T.; Diamond, D. Photonic modulation of surface properties: A novel concept in chemical sensing. J. Phys. D-Appl. Phys. 2007, 40, 7238–7244, doi:10.1088/0022-3727/40/23/S06.
[54]
Coleman, S.; Byrne, R.; Minkovska, S.; Diamond, D. Thermal reversion of spirooxazine in ionic liquids containing the [NTf2](-) anion. Pccp. Phys. Chem. Chem. Phys. 2009, 11, 5608–5614, doi:10.1039/b901417a.
[55]
Byrne, R.; Coleman, S.; Fraser, K.J.; Raduta, A.; MacFarlane, D.R.; Diamond, D. Photochromism of nitrobenzospiropyran in phosphonium based ionic liquids. Pccp. Phys. Chem. Chem. Phys. 2009, 11, 7286–7291, doi:10.1039/b903772a.
[56]
Wagner, K.; Byrne, R.; Zanoni, M.; Gambhir, S.; Dennany, L.; Breukers, R.; Higgins, M.; Wagner, P.; Diamond, D.; Wallace, G.G.; et al. A multiswitchable poly(terthiophene) bearing a spiropyran functionality: Understanding photo- and electrochemical control. J. Am. Chem. Soc. 2011, 133, 5453–5462, doi:10.1021/ja1114634. 21417306
[57]
Szilagyi, A.; Sumaru, K.; Sugiura, S.; Takagi, T.; Shinbo, T.; Zrinyi, M.; Kanamori, T. Rewritable microrelief formation on photoresponsive hydrogel layers. Chem. Mater 2007, 19, 2730–2732, doi:10.1021/cm070444v.
[58]
Byrne, R.; Ventura, C.; Lopez, F.B.; Walther, A.; Heise, A.; Diamond, D. Characterisation and analytical potential of a photo-responsive polymeric material based on spiropyran. Biosens. Bioelectron. 2010, 26, 1392–1398, doi:10.1016/j.bios.2010.07.059.
[59]
Brazel, C.S.; Peppas, N.A. Synthesis and characterization of thermomechanically and chemomechanically responsive poly(N-isopropylacrylamide-co-methacrylic acid) hydrogels. Macromolecules 1995, 28, 8016–8020, doi:10.1021/ma00128a007.
[60]
Schild, H.G.; Tirrell, D.A. Interaction of poly(N-isopropylacrylamide) with sodium normal-alkyl sulfates in aqueous-solution. Langmuir 1991, 7, 665–671, doi:10.1021/la00052a013.
[61]
Bakker, E.; Buehlmann, P.; Pretsch, E. Carrier-based ion-selective electrodes and bulk optodes. 1. General Characteristics. Chem. Rev. 1997, 97, 3083–3132, doi:10.1021/cr940394a.
[62]
Bakker, E.; Xu, A.P.; Pretsch, E. Optimum composition of neutral carrier based Ph electrodes. Anal. Chim. Acta 1994, 295, 253–262, doi:10.1016/0003-2670(94)80230-0.
[63]
Malon, A.; Radu, A.; Qin, W.; Qin, Y.; Ceresa, A.; Maj-Zurawska, M.; Bakker, E.; Pretsch, E. Improving the detection limit of anion-selective electrodes: An iodide-selective membrane with a nanomolar detection limit. Anal. Chem. 2003, 75, 3865–3871, doi:10.1021/ac026454r. 14572055
[64]
Sutter, J.; Radu, A.; Peper, S.; Bakker, E.; Pretsch, E. Solid-contact polymeric membrane electrodes with detection limits in the subnanomolar range. Anal. Chim. Acta 2004, 523, 53–59, doi:10.1016/j.aca.2004.07.016.
[65]
Ceresa, A.; Radu, A.; Peper, S.; Bakker, E.; Pretsch, E. Rational design of potentiometric trace level ion sensors. A Ag+-selective electrode with a 100 ppt detection limit. Anal. Chem. 2002, 74, 4027–4036, doi:10.1021/ac025548y.
[66]
Del Sesto, R.E.; Corley, C.; Robertson, A.; Wilkes, J.S. Tetraalkylphosphonium-based ionic liquids. J. Organomet. Chem. 2005, 690, 2536–2542, doi:10.1016/j.jorganchem.2004.09.060.
[67]
Peng, B.; Zhu, J.W.; Liu, X.J.; Qin, Y. Potentiometric response of ion-selective membranes with ionic liquids as ion-exchanger and plasticizer. Sensor. Actuator. B-Chem. 2008, 133, 308–314, doi:10.1016/j.snb.2008.02.027.
[68]
Shvedene, N.V.; Chernyshov, D.V.; Khrenova, M.G.; Formanovsky, A.A.; Baulin, V.E.; Pletnev, I.V. Ionic liquids plasticize and bring ion-sensing ability to polymer membranes of selective electrodes. Electroanalysis 2006, 18, 1416–1421, doi:10.1002/elan.200603537.
[69]
Buhlmann, P.; Pretsch, E.; Bakker, E. Carrier-based ion-selective electrodes and bulk optodes. 2. Ionophores for potentiometric and optical sensors. Chem. Rev. 1998, 98, 1593–1687, doi:10.1021/cr970113+.
[70]
Chernyshov, D.V.; Shuedene, N.V.; Antipova, E.R.; Pletnev, I.V. Ionic liquid-based miniature electrochemical sensors for the voltammetric determination of catecholamines. Anal. Chim. Acta 2008, 621, 178–184, doi:10.1016/j.aca.2008.05.042.
[71]
Nadherna, M.; Opekar, F.; Reiter, J. Ionic liquid-polymer electrolyte for amperometric solid-state NO(2) sensor. Electrochim. Acta 2011, 56, 5650–5655, doi:10.1016/j.electacta.2011.04.022.
[72]
Bird, C.L.; Kuhn, A.T. Electrochemistry of the viologens. Chem. Soc. Rev. 1981, 10, 49–82, doi:10.1039/cs9811000049.
[73]
Mortimer, R.J.; Dyer, A.L.; Reynolds, J.R. Electrochromic organic and polymeric materials for display applications. Displays 2006, 27, 2–18, doi:10.1016/j.displa.2005.03.003.
[74]
Rosseinsky, D.R.; Mortimer, R.J. Electrochromic systems and the prospects for devices. Adv. Mater 2001, 13, 783–793, doi:10.1002/1521-4095(200106)13:11<783::AID-ADMA783>3.0.CO;2-D.
[75]
Wishart, J.F. Energy applications of ionic liquids. Energy Environ. Sci. 2009, 2, 956–961, doi:10.1039/b906273d.
[76]
Ahmad, S.; Deepa, M. Ionogels encompassing ionic liquid with liquid like performance preferable for fast solid state electrochromic devices. Electrochem. Commun. 2007, 9, 1635–1638, doi:10.1016/j.elecom.2007.02.022.
[77]
Kavanagh, A.; Fraser, K.; Byrne, R.; Diamond, D. An electrochromic ionic liquid: Design, characterisation and incorporation into a solid-state devices. Chem. Mater 2011. Submitted.
[78]
Deepa, M.; Ahmad, S.; Sood, K.N.; Alam, J.; Ahmad, S.; Srivastava, A.K. Electrochromic properties of polyaniline thin film nanostructures derived from solutions of ionic liquid/polyethylene glycol. Electrochim. Acta 2007, 52, 7453–7463, doi:10.1016/j.electacta.2007.06.031.
[79]
Ahmad, S.; Singh, S. Electrochromic device based on carbon nanotubes functionalized poly(methyl pyrrole) synthesized in hydrophobic ionic liquid medium. Electrochem. Commun. 2008, 10, 895–898, doi:10.1016/j.elecom.2008.04.014.
[80]
Deepa, M.; Awadhia, A.; Bhandari, S. Electrochemistry of poly(3,4-ethylenedioxythiophene)-polyaniline/Prussian blue electrochromic devices containing an ionic liquid based gel electrolyte film. Pccp. Phys. Chem. Chem. Phys. 2009, 11, 5674–5685, doi:10.1039/b900091g.
[81]
Oehme, I.; Wolfbeis, O.S. Optical sensors for determination of heavy metal ions. Mikrochim. Acta 1997, 126, 177–192, doi:10.1007/BF01242319.
[82]
Zhu, J.W.; Zhai, J.Y.; Li, X.; Qin, Y. Applications of hydrophobic room temperature ionic liquids in ion-selective optodes. Sensor. Actuator. B-Chem. 2011, 159, 256–260, doi:10.1016/j.snb.2011.06.084.
[83]
Topal, S.Z.; Ertekin, K.; Gurek, A.G.; Yenigul, B.; Ahsen, V. Tuning pH sensitivities of zinc phthalocyanines in ionic liquid modified matrices. Sensor. Actuator. B-Chem. 2011, 156, 236–244, doi:10.1016/j.snb.2011.04.026.
[84]
Lunstroot, K.; Driesen, K.; Nockemann, P.; Gorller-Walrand, C.; Binnemans, K.; Bellayer, S.; Bideau, J.L.; Vioux, A. Luminescent ionogels based on europium-doped ionic liquids confined within silica-derived networks. Chem. Mater 2006, 18, 5711–5715, doi:10.1021/cm061704w.
[85]
Lunstroot, K.; Driesen, K.; Nockemann, P.; Van Hecke, K.; Van Meervelt, L.; Goerller-Walrand, C.; Binnemans, K.; Bellayer, S.; Viau, L.; Le Bideau, J.; et al. Lanthanide-doped luminescent ionogels. Dalton. Trans. 2009, 298–306.
[86]
Cheminet, N.; Jarrosson, T.; Lere-Porte, J.-P.; Serein-Spirau, F.; Cury, L.; Moreau, J.; Viau, L.; Vioux, A. One pot synthesis of fluorescent pi-conjugated materials: Immobilization of phenylene-ethynylene polyelectrolytes in silica confined ionogels. J. Mater. Chem. 2011, 21, 13588–13593, doi:10.1039/c1jm11733e.
[87]
Wassercheid, P.; Welton, T. Ionic Liquids in Synthesis; Wiley-VCH: Weinheim, Germany, 2003.
[88]
Liu, Y.; Wang, M.; Li, J.; Li, Z.; He, P.; Liu, H.; Li, J. Highly active horseradish peroxidase immobilized in 1-butyl-3-methylimidazolium tetrafluoroborate room-temperature ionic liquid based sol-gel host materials. Chem. Commun. 2005, 1778–1780.
[89]
Ohno, H.; Suzuki, C.; Fukumoto, K.; Yoshizawa, M.; Fujita, K. Electron transfer process of poly(ethylene oxide)-modified Cytochrome C in imidazolium type ionic liquid. Chem. Lett. 2003, 32, 450–451, doi:10.1246/cl.2003.450.
[90]
Baker, S.N.; McCleskey, T.M.; Pandey, S.; Baker, G.A. Fluorescence studies of protein thermostability in ionic liquids. Chem. Commun. 2004, 940–941.
[91]
Pernak, A.; Iwanik, K.; Majewski, P.; Grzymislawski, M.; Pernak, J. Ionic liquids as an alternative to formalin in histopathological diagnosis. Acta Histochem. 2005, 107, 149–156, doi:10.1016/j.acthis.2005.02.003.
[92]
Fujita, K.; MacFarlane, D.R.; Forsyth, M. Protein solubilising and stabilising ionic liquids. Chem. Commun. 2005, 4804–4806.
[93]
Laszlo, J.A.; Compton, D.L. Comparison of peroxidase activities of hemin, cytochrome c and microperoxidase-11 in molecular solvents and imidazolium-based ionic liquids. J. Mol. Catal. B Enzym. 2002, 18, 109–120, doi:10.1016/S1381-1177(02)00074-7.
[94]
Yang, Z.; Pan, W. Ionic liquids: Green solvents for nonaqueous biocatalysis. Enzyme Microb. Technol. 2005, 37, 19–28, doi:10.1016/j.enzmictec.2005.02.014.
[95]
Zhao, H. Methods for stabilizing and activating enzymes in ionic liquids—A review. J. Chem. Tech. Biotech. 2010, 85, 891–907, doi:10.1002/jctb.2375.
[96]
Abe, Y.; Yoshiyama, K.; Yagi, Y.; Hayase, S.; Kawatsura, M.; Itoh, T. A rational design of phosphonium salt type ionic liquids for ionic liquid coated-lipase catalyzed reaction. Green Chem. 2010, 12, 1976–1980, doi:10.1039/c0gc00151a.
[97]
Zhang, Y.; Zheng, J. Direct electrochemistry and electrocatalysis of myoglobin immobilized in hyaluronic acid and room temperature ionic liquids composite film. Electrochem. Commun. 2008, 10, 1400–1403, doi:10.1016/j.elecom.2008.07.022.
[98]
Zhang, J.; Lei, J.; Liu, Y.; Zhao, J.; Ju, H. Highly sensitive amperometric biosensors for phenols based on polyaniline-ionic liquid-carbon nanofiber composite. Biosens. Bioelectron. 2009, 24, 1858–1863, doi:10.1016/j.bios.2008.09.012.
[99]
Torimoto, T.; Tsuda, T.; Okazaki, K.-I.; Kuwabata, S. New frontiers in materials science opened by ionic liquids. Adv. Mater. 2010, 22, 1196–1221, doi:10.1002/adma.200902184.
[100]
Ohno, K.-I.; Tachikawa, K.; Manz, A. Microfluidics: Applications for analytical purposes in chemistry and biochemistry. Electrophoresis 2008, 29, 4443–4453, doi:10.1002/elps.200800121.
[101]
Brady, S.; Dunne, L.E.; Lynch, A.; Smyth, B.; Diamond, D. Personalised Health Management Systems: The Integration of Innovative Sensing, Textile, Information and Communication Technologies; IOS Press: Amsterdam, The Netherlands, 2005; Volume 117.
[102]
Bhandari, P.; Narahari, T.; Dendukuri, D. Fab-chips’: A versatile, fabric-based platform for low-cost, rapid and multiplexed diagnostics. Lab Chip 2011, 11, 2493–2499, doi:10.1039/c1lc20373h.
[103]
Schmid-Wendtner, M.H.; Korting, H.C. The pH of the skin surface and its impact on the barrier function. Skin Pharmacol. Physiol. 2006, 19, 296–302, doi:10.1159/000094670.
[104]
Patterson, M.J.; Galloway, S.D.R.; Nimmo, M.A. Effect of induced metabolic alkalosis on sweat composition in men. Acta Physiol. Scand. 2002, 174, 41–46, doi:10.1046/j.1365-201x.2002.00927.x.
[105]
Granger, D.; Marsolais, M.; Burry, J.; Laprade, R. Na+/H+ exchangers in the human eccrine sweat duct. Amer. J. Physiol.-Cell Physiol. 2003, 285, C1047–C1058.
[106]
Patterson, M.J.; Galloway, S.D.R.; Nimmo, M.A. Variations in regional sweat composition in normal human males. Exp. Physiol. 2000, 85, 869–875, doi:10.1017/S0958067000020583.
[107]
Morgan, R.M.; Patterson, M.J.; Nimmo, M.A. Acute effects of dehydration on sweat composition in men during prolonged exercise in the heat. Acta Physiol. Scand. 2004, 182, 37–43, doi:10.1111/j.1365-201X.2004.01305.x.
[108]
O’Toole, M.; Shepherd, R.; Wallace, G.G.; Diamond, D. Inkjet printed LED based pH chemical sensor for gas sensing. Anal. Chim. Acta 2009, 652, 308–314, doi:10.1016/j.aca.2009.07.019.
Benito-Lopez, F.; Coyle, S.; Byrne, R.; O’Toole, C.; Barry, C.; Diamond, D. Simple barcode system based on inonogels for real time pH-sweat monitoring. Body Sensor Networks (BSN) 2010, 291–296.
[111]
Coyle, S.; Benito-Lopez, F.; Radu, T.; Lau, K.T.; Diamond, D. Fibers and fabrics for chemical and biological sensing. J. Text. App. 2010, 14, 64.
[112]
Nilsson, D.; Kugler, T.; Svensson, P.-O.; Berggren, M. An all-organic sensor-transistor based on a novel electrochemical transducer concept printed electrochemical sensors on paper. Sensor. Actuator. B Chem. 2002, 86, 193–197, doi:10.1016/S0925-4005(02)00170-3.
[113]
Chaubey, A.; Pande, K.K.; Singh, V.S.; Malhotra, B.D. Co-immobilization of lactate oxidase and lactate dehydrogenase on conducting polyaniline films. Anal. Chim. Acta 2000, 407, 97–103, doi:10.1016/S0003-2670(99)00797-7.
[114]
Weber, J.; Kumar, A.; Kumar, A.; Bhansali, S. Novel lactate and pH biosensor for skin and sweat analysis based on single walled carbon nanotubes. Sensor. Actuator. B Chem. 2006, 117, 308–313, doi:10.1016/j.snb.2005.12.025.
Cai, X.; Yan, J.; Chu, H.; Wu, M.; Tu, Y. An exercise degree monitoring biosensor based on electrochemiluminescent detection of lactate in sweat. Sensor. Actuator. B Chem. 2010, 143, 655–659, doi:10.1016/j.snb.2009.10.002.
[117]
Wang, Y.; Xu, H.; Zhang, J.M.; Li, G. Electrochemical sensors for clinic analysis. Sensors 2008, 8, 2043–2081, doi:10.3390/s8042043.
[118]
Weil, M.H.; Afifi, A.A. Experimental and clinical studies on lactate and pyruvate as indicators of the severity of acute circulatory failure (shock). Circulation 1970, 41, 989–1001, doi:10.1161/01.CIR.41.6.989.
[119]
Green, J.M.; Pritchett, R.C.; Crews, T.R.; McLester, J.R.; Tucker, D.C. Sweat lactate response between males with high and low aerobic fitness. Eur. J. Appl. Physiol. 2004, 91, 1–6, doi:10.1007/s00421-003-0968-2.
[120]
Billat, L.V. Use of blood lactate measurements for prediction of exercise performance and for control of training: Recommendations for long-distance running. Sports Med. 1996, 22, 157–175, doi:10.2165/00007256-199622030-00003.
