Ionogel-based light-actuated valves for controlling liquid flow in micro-fluidic manifolds.

We present the fabrication, characterisation and performance of four novel ionic liquid polymer gels (ionogels) as photo-actuated valves incorporated into micro-fluidic manifolds. The ionogels incorporate benzospiropyran units and phosphonium-based ionic liquids. Each ionogel is photo-polymerised in situ in the channels of a poly(methyl methacrylate) micro-fluidic device, generating a manifold incorporating four different micro-valves. The valves are actuated by simply applying localised white light irradiation, meaning that no physical contact between the actuation impulse (light) and the valve structure is required. Through variation of the composition of the ionogels, each of the micro-valves can be tuned to open at different times under similar illumination conditions. Therefore, flows through the manifold can be independently controlled by a single light source. At present, the contraction process to open the channel is relatively rapid (seconds) while the recovery (expansion) process to re-close the channel is relatively slow (minutes), meaning that the valve, in its current form, is better suited for single-actuation events.

[1]  Lei Zhai,et al.  Conformal switchable superhydrophobic/hydrophilic surfaces for microscale flow control , 2009 .

[2]  Shinji Sugiura,et al.  Photoresponsive polymer gel microvalves controlled by local light irradiation , 2007 .

[3]  Ziniu Yu,et al.  Dissolution of cellulose with ionic liquids and its application : a mini-review , 2006 .

[4]  Toshiyuki Kanamori,et al.  Reversible and Efficient Proton Dissociation of Spirobenzopyran-Functionalized Poly(N-isopropylacrylamide) in Aqueous Solution Triggered by Light Irradiation and Temporary Temperature Rise , 2004 .

[5]  S. Digumarthy,et al.  Isolation of rare circulating tumour cells in cancer patients by microchip technology , 2007, Nature.

[6]  Toshiyuki Kanamori,et al.  Photoresponsive properties of poly(N-isopropylacrylamide) hydrogel partly modified with spirobenzopyran. , 2006, Langmuir : the ACS journal of surfaces and colloids.

[7]  J L West,et al.  Independent Optical Control of Microfluidic Valves Formed from Optomechanically Responsive Nanocomposite Hydrogels , 2005, Advanced materials.

[8]  Miklós Zrínyi,et al.  Rewritable microrelief formation on photoresponsive hydrogel layers , 2007 .

[9]  Maria Forsyth,et al.  Solution- surface electropolymerization : A route to morphologically novel poly(pyrrole) using an ionic liquid , 2006 .

[10]  Masayoshi Watanabe,et al.  Macromolecules in Ionic Liquids: Progress, Challenges, and Opportunities , 2008 .

[11]  Yugong Xu,et al.  Arrayed pH-responsive microvalves controlled by multiphase laminar flow , 2007 .

[12]  S. Saha,et al.  Local structure formation in alkyl-imidazolium-based ionic liquids as revealed by linear and nonlinear Raman spectroscopy. , 2007, Accounts of chemical research.

[13]  Frantisek Svec,et al.  Light-actuated high pressure-resisting microvalve for on-chip flow control based on thermo-responsive nanostructured polymer. , 2008, Lab on a chip.

[14]  Louis-S. Bouchard,et al.  NMR Imaging of Catalytic Hydrogenation in Microreactors with the Use of para-Hydrogen , 2008, Science.

[15]  Chong H. Ahn,et al.  Institute of Physics Publishing Journal of Micromechanics and Microengineering a Review of Microvalves , 2022 .

[16]  Miklós Zrínyi,et al.  On-demand microfluidic control by micropatterned light irradiation of a photoresponsive hydrogel sheet. , 2009, Lab on a chip.

[17]  J. Katine,et al.  Current-induced magnetization reversal in nanopillars with perpendicular anisotropy , 2006 .

[18]  Dermot Diamond,et al.  Photochromism of nitrobenzospiropyran in phosphonium based ionic liquids. , 2009, Physical chemistry chemical physics : PCCP.

[19]  G. G. Stokes.  "J." , 1890, The New Yale Book of Quotations.

[20]  Guangtao Li,et al.  Photonic Ionic Liquids Polymer for Naked‐Eye Detection of Anions , 2008 .

[21]  Richard E. Eitel,et al.  Magnetic hydrogel nanocomposites as remote controlled microfluidic valves. , 2009, Lab on a chip.

[22]  Ram S. Mohan,et al.  Reactivity of ionic liquids , 2007 .

[23]  Yoon‐Kyoung Cho,et al.  Multifunctional microvalves control by optical illumination on nanoheaters and its application in centrifugal microfluidic devices. , 2007, Lab on a chip.

[24]  J. Baek,et al.  Photopolymerized check valve and its integration into a pneumatic pumping system for biocompatible sample delivery. , 2006, Lab on a chip.

[25]  Monica Brivio,et al.  Miniaturized continuous flow reaction vessels: influence on chemical reactions. , 2006, Lab on a chip.

[26]  Sheila N. Baker,et al.  The large scale synthesis of pure imidazolium and pyrrolidinium ionic liquids , 2007 .

[27]  Shu Yang,et al.  Self-Actuated, Thermo-Responsive Hydrogel Valves for Lab on a Chip , 2005, Biomedical microdevices.

[28]  Dermot Diamond,et al.  LED switching of spiropyran-doped polymer films , 2006 .

[29]  H. Waldmann,et al.  Organic Synthesis Highlights , 1990 .

[30]  Andreas Manz,et al.  Micro total analysis systems: latest achievements. , 2008, Analytical chemistry.

[31]  Peter Wasserscheid.  Recent Developments in Using Ionic Liquids as Solvents and Catalysts for Organic Synthesis , 2003 .

[32]  Dongshin Kim,et al.  A bi-polymer micro one-way valve , 2007 .

[33]  D. Macfarlane,et al.  Structural Characterization of Novel Ionic Materials Incorporating the Bis(trifluoromethanesulfonyl)amide Anion , 2002 .

[34]  T. Shinbo,et al.  Characteristic Phase Transition of Aqueous Solution of Poly(N-isopropylacrylamide) Functionalized with Spirobenzopyran , 2004 .

[35]  A. Ryan,et al.  Chemical actuation in responsive hydrogels , 2009 .

[36]  Dermot Diamond,et al.  Photo- and solvatochromic properties of nitrobenzospiropyran in ionic liquids containing the [NTf2]- anion. , 2008, Physical chemistry chemical physics : PCCP.

[37]  C. Chiappe,et al.  Ionic liquids: solvent properties and organic reactivity , 2005 .

[38]  W. Marsden.  I and J , 2012 .