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Covalent immobilization of a fluorescent pH-sensitive naphthalimide dye in sol–gel films

  • Antje Kriltz
  • Christin Löser
  • Gerhard J. Mohr
  • Sabine Trupp
Original Paper

Abstract

A pH indicator dye was covalently linked to inorganic–organic hybrid sol–gel layers via its carboxyl function by the formation of an amide bond. For this, the dye was activated by 2-succinimido-1,1,3,3-tetramethyluronium tetrafluoroborate and linked to N-(3-(trimethoxysilyl)propyl)-ethylendiamine. Different ratios of tetraethoxy-silane, diisobutyldimethoxysilane and 3-glycidoxypropyltrimethoxysilane were evaluated to tailor the performance of the sensing material. Fluorescence spectroscopy of the optimised sensor layers with a molar ratio of organically modified siloxane to tetraethoxysilane of 25.9 and of dye/amino groups of 1.16, showed a reversible fluorescence signal increase of 117 % upon protonation, and a pk a 6.5. The signal changes were caused by photoinduced electron transfer between the methylpiperazine moiety and the naphthalimide fluorophore, its efficiency being modulated by protonation of the methylpiperazine nitrogen. The influence of parameters such as synthesis, dip-coating process and heat-treatment on the performance of the sensor layers was investigated. Optimum signal changes were obtained when heating the sol–gel structure up to 170 °C.

Keywords

Sol–gel pH indicator dye Naphthalimide-based receptor Fluorescent dye 

Notes

Acknowledgments

S. Trupp and G. J. Mohr were kindly supported by the Bayerische Staatsministerium für Wirtschaft, Infrastruktur, Verkehr und Technologie within project AZ-Nr.: 20.10-3410-2 (Projekt Sensormaterialien).

References

  1. 1.
    Trupp S (2009) Charakterisierung und Immobilisierung von fluoreszierenden Sensorfarbstoffen zur pH- und Saccharidbestimmung. PhD thesis, JenaGoogle Scholar
  2. 2.
    Trupp S, Hoffmann P, Henkel T, Mohr GJ (2008) Novel pH indicator dyes for array preparation via NHS ester activation or solid-phase organic synthesis. Org Biomol Chem 6:4319–4321CrossRefGoogle Scholar
  3. 3.
    Moro AJ, Schmidt J, Doussineau T, Lapresta-Fernandez A, Wegener J, Mohr GJ (2011) Surface functionalized fluorescent silica nanoparticles for the detection of ATP. Cem Commun 47:6066–6068CrossRefGoogle Scholar
  4. 4.
    Trupp S, Schweitzer A, Mohr GJ (2006) A fluorescent water-soluble naphthalimide receptor for saccharides with highest sensitivity in the physiological pH range. Org Biomol Chem 4:2965–2968CrossRefGoogle Scholar
  5. 5.
    Doussineau T, Schulz A, Lapresta-Fernandez A, Moro A, Koersten S, Trupp S, Mohr GJ (2010) On the design of fluorescent ratiometric nanosensors. Chem A Eur J 16: 102900–10299Google Scholar
  6. 6.
    Trupp S, Alberti M, Carofiglio T, Lubian E, Lehmann H, Heuermann R, Yacoub-George E, Bock K, Mohr GJ (2010) Development of pH sensitive indicator dyes for the preparation of micro patterned optical sensor layers. Sens Actuators B 150:206–210CrossRefGoogle Scholar
  7. 7.
    Mohr GJ (2006) Polymers for optical sensors. In: Baldini F, Chester AN, Homola J (eds) Advanced study course on optical sensors. NATO ASI Series, Kluwer, Dordrecht, pp 297–321CrossRefGoogle Scholar
  8. 8.
    Jellyman PE, Procter MA, Procter JP (1955) J Soc Glass Technol 39:173–192Google Scholar
  9. 9.
    Neuroth N (1968) Glastechnol Ber 41:243Google Scholar
  10. 10.
    Brinker CJ, Scherer GW (1990) Sol-gel science. Academic Press, BostonGoogle Scholar
  11. 11.
    Lide DR (2006) Handbook of chemistry and physics. CRC Press Taylor Francis Group, Boca RatonGoogle Scholar
  12. 12.
    Quma Elektronik (2011) Wuppertal. http:www.quma.de/ger/beschrei/dielektr.htm#ziel_T. Accessed 19 Aug 2011
  13. 13.
    Colthup NB (1950) J Opt Soc Am 40(6): 397Google Scholar
  14. 14.
    Grünzler H, Böck H (1983) IR-Spektroskopie—Eine Einführung. Verlag Chemie GmbH, WeinheimGoogle Scholar
  15. 15.
    L.O.T. ORIEL gmbH Co KG (2003) Variable angle spectroscopy ellipsometry measurements results. DarmstadtGoogle Scholar
  16. 16.
    Haller W (1981) Bunsenges Phys Chem 85:847–850Google Scholar
  17. 17.
    Schulz A, Wotschadlo J, Heinze T, Mohr GJ (2010) J Mater Chem 20:1475–1482CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  • Antje Kriltz
    • 1
  • Christin Löser
    • 1
  • Gerhard J. Mohr
    • 2
  • Sabine Trupp
    • 2
  1. 1.Institut für Physikalische ChemieFriedrich-Schiller-Universität JenaJenaGermany
  2. 2.Fraunhofer Research Institution for Modular Solid-State Technologies EMFT, Workgroup Sensor MaterialsRegensburgGermany

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