UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE The inherent physical, optical and conductivity properties of Ionic Liquid – polymeric membranes : a self indicating, simultaneous response upon coordination to transition metal ions. Andrew Kavanagh MACRO 2010 Glasgow, Scotland 14 th July 2010

UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE Me.. Graduated with B.Sc (Hons) in Chemical & Pharmaceutical Sciences, Dublin City University (2008). PhD. in “Ionic Liquids and their use in the development of potential chemical sensors”. Sept 08’ Supervisors Dr. Aleksandar Radu & Prof. Dermot Diamond

UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE Outline Ionic Liquids Polymeric Optodes Ionic Liquid – PVC Optodes Vibrational Spectroscopy UV/Vis Characterisation Alternate Detection Techniques Wireless Radio Frequency Detection Electrochemical Impedance Spectroscopy Portable X-Ray Fluorescence

UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE Ionic Liquids Unique combination of ions that are liquid at room temperature Choice of ion pair can have dramatic impact on Density Viscosity Miscibility with Solvents

UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE Applications of IL’s Synthesis & Catalysis in Organic Chemistry => Good thermal stability Electrochemistry => Good Conductivity and a large electrochemical window Analytical Chemistry => Stable stationary phase for separations

UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE Polymeric Optodes Typically contain up to 5 components Polymer Inert matrix to house active sensing components Plasticizer Lowers T g of polymer to produce solid film Ion-Exchanger Facilitates Ion Transfer from aq. to organic phase Ionophore Selectively binds ion of interest Transducer Dye Produces optical response A. Radu, R. Byrne, N. Alhashimy and D. Diamond, Abstr. Pap. Am. Chem. Soc., 2006, 231, 41-INOR. PMMA optodes containing Spiropyran dye

UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE Cu 2+ /Co 2+ Co 2+ Cu 2+ Simple, 2-component optodes [P 6,6,6,14 ][DCA] acts as plasticizer ion-exchanger ligand transducer dye Upon exposure to Cu 2+ and Co 2+

UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE Vibrational Spectroscopy IR Raman ν max Cu-DCA : 2162 cm -1 ν max Co-DCA : 2166 cm -1

UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE Multianalyte Recognition

UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE Stoichiometry Estimation Best fit was found to be 2M for 1L

UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE Dicyanamide Used to impart low viscosity in a new generation of Ionic Liquids Pseudohalide, shown in literature to bind to an array of TM elements Due to strong electron delocalisation across molecule, resulting in a variety of binding modes Rich binding diversity results in many 1,2 and 3-D co-ordinated networks reported S. R. Batten, P. Jensen, B. Moubaraki, K. S. Murray and R. Robson, Chem. Commun., 1998, S. R. Batten and K. S. Murray, Coordination Chemistry Reviews, 2003, 246, M DCA

UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE Interference Spectra J. Kohout, L. Jager, M. Hvastijova and J. Kozisek, J. Coord. Chem., 2000, 51, DCA - exhibits a higher binding preferentiality for Cu 2+ over Co 2+ Ni 2+ has been shown to bind to DCA -, yet produces no optical response

UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE RF Wireless Conductivity Detection In conjunction with CSIRO Laboratories, Melbourne, Australia Works by passing low voltage, low frequency AC signal from transmitting to receiving electrodes Sample is housed in an insulating container Conductive sample produces a signal as it passes through the electrode field

UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE RF Wireless Conductivity Detection Depending on pH, polyaniline (PAni) can switch between conductive and non-conductive forms Ink jet printed Pani dispersion sensitive to both Ammonia and Acetic Acid vapour N. B. Clark and L. J. Maher, Reactive & Functional Polymers, 2009, 69,

UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE Wireless Recognition of Conductive Membranes WRF has the required sensitivity to distinguish between complexed and non-complexed membranes “Edge effects” occur as insulating material first enters and leaves electrode channel Membrane Group:Ionic LiquidCopperMixCobalt PVC: IL (1:2) PVC: IL (1:1) PVC: IL (2:1)

UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE Screen Printed Electrodes PET substrate Ag/AgCl ink used as conducting path Carbon Paste used as working electrode Insulating Layer defines the working area Conducting polymer (Poly (3-octylthiophene)) is first dropcast to aid ionic to electronic transition PVC-IL cocktail dropcast and allowed to dry A. Morrin, A. J. Killard and M. R. Smyth, Analytical Letters, 2003, 36,

UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE Impedance Spectroscopy PVC:IL 1:2 (w/w) PVC:IL (1:1 w/w)

UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE LOD Calcualtions Cu-DCA LOD:7.62 x 10-4M Co-DCA LOD:2.91 x 10-4M Cu-DCA LOD: 7.55 x M

UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE XRF Results Used to quantify [DCA] - binding preferentiality Co levels were found to be 45% lower Even as a mixture (2:1 Co:Cu (vol.)) Co levels are 88% lower! MembraneCopper:Cobalt:MixtureBlank Composition:Copper:Cobalt:Copper:Cobalt: 1. PVC:IL (1:1 w/w) (165.73) (153.38) (164.43) (83.39) (21.56) ( ) 2. PVC:IL (1:2 w/w) (424.75) (371.17) (357.98) (179.21) (81.51) < LOD 3. PVC:IL (2:1 w/w) (77.79) < LOD (90.91) (88.09) < LOD

UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE Conclusions The Ionic Liquid [P 6,6,6,14 ][DCA] fulfils multiple roles in polymeric optodes Conductive membranes allow for detection via an array of techniques The relative ease of synthesis and diversity allows for the possibility of new IL’s with greater selectivity

UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE Acknowledgements Dr. Aleksandar Radu and Professor Dermot Diamond Everyone at ASG Dr’s. Noel Clarke and Matthius Hilder at CSIRO Cytec Industries DCU Research Career Start Fellowship 2008 Science Foundation Ireland (grant 07/CE/I1147) Enterprise Ireland (grant 07/RFP/MASF812)

UNIVERSITY COLLEGE DUBLIN  DUBLIN CITY UNIVERSITY  TYNDALL NATIONAL INSTITUTE Thanks for listening!