DOI QR코드

DOI QR Code

pH Measurements with a Microcantilever Array-Based Biosensor System

  • Hur, Shin (Nature-Inspired Nanoconvergence System, Korea Institute of Machinery and Materials) ;
  • Jung, Young-Do (Nature-Inspired Nanoconvergence System, Korea Institute of Machinery and Materials)
  • Received : 2012.04.16
  • Accepted : 2012.05.17
  • Published : 2012.05.31

Abstract

In this paper, we present a pH measurement method that uses a microcantilever-array-based biosensor system. It is composed of microcantilever array, liquid cell, micro syringe pump, laser diode array, position sensitive detector, data acquisition device, and data processing software. Four microcantilevers are functionalized with pH-sensitive MHA(mercaptohexadecanoic acid) as a probe, while three microcantilevers are functionalized with HDT(hexadecane thiol) as reference. We prepare PBS(phosphate buffered saline) solutions of different pH and inject them into the liquid cell with a predefined volumetric speed at regular time intervals. The functionalized mircocantilevers in the liquid cell deflect as a self-assembled monolayer on the microcantilever binds with probe molecules in the solution. The difference in deflection between the MHA-covered probe microcantilever and the HDT-covered reference microcantilever was used to compensate for thermal drift. The deflection difference clearly increases with increasing pH in the solution. It was shown that when the pH values of the PBS solutions are high, there were large variations in the deflection of microcantilevers, whereas there were small variations for low pH value. The experimental results show that the microcantilever array functionalized with MHA and HDT can detect pH value with good repeatability.

Keywords

References

  1. G. Li, L.W. Burggraf, and W.P. Baker, "Photothermal spectroscopy using multilayer cantilever for chemical detection", Applied Physics Letters, pp.1122-1125, 2000.
  2. T. Gotoh, "Photothermal technique using individual cantilevers for quality monitoring in thin film devices", Review of Scientific Instruments, pp. 074902-1-4, 2009.
  3. R. Berger, E. Delamarche, H.P. Lang. Ch. Gerber, and K. Gimzewski, "Surface stress in the self-assembly of alkanethiols on gold", Physical Sciences, pp. 1-7, 1997.
  4. G. Meyer and N.M. Amer, "Optical-beam-deflection atomic force microscopy: The NaCl (001) surface", Appl. Phys. Lett. 56, pp. 2100-2101, 1990. https://doi.org/10.1063/1.102985
  5. Fritz, M.K., M.K. Baller, H.P. Lang, T. Strunz, E. Meyer, H.-J. Guntherodt, E. Delamarche, Ch. Gerber, and J. K. Gimzewski, "Stress at the solid-liquid interface of self-assembled monolayers on gold investigated with a nanomechanical Sensor", Langmuir, pp. 9694-9696, 2000.
  6. R. Berger, E. Delamarche, H.P. Lang, Ch. Gerber, J.K. Gimzewski, E. Meyer, and H.-J. Guntherodt, "Surface stress in the self-assembly of alkanethiols on gold probed by a force microscopy technique", Applied Physics. A, pp. 55-59, 1998.
  7. H.-F. Ji, K.M. Hansen, Z. Hu, and T. Thundat, "Detection of pH variation using modified microcantilever sensors", Sens. Actuators, B, vol. 72, p. 233, 2001. https://doi.org/10.1016/S0925-4005(00)00678-X
  8. S. Huang, H. Tao, I. Lin, and X. Zhang, "Development of double-cantilever infrared detectors: Fabrication, curvature control and demonstration of thermal detection", Sensors and Actuators A: Physical, pp. 231-240, 2008.
  9. G. Wu, R.H. Datar, K.M. Hansen, T. Thundat, R.J. Cote, and A. Majumdar, "Bioassay of prostate-specific antigen(PSA) using microcantilevers", Nature Biotechnology, vol. 19, p. 856, 2001. https://doi.org/10.1038/nbt0901-856
  10. N. Blanc, J. Brugger and N.F. de Rooij, "Scanning force microscopy in the dynamic mode using microfabricated capacitive sensors", J. Vac. Sci. Technol. B, vol. 14, p. 901, 1996. https://doi.org/10.1116/1.589171
  11. T. Thundat, E.A. Wachter, S.L. Sharp, and R.J. Warmack, "Detection of mercury vapor using resonating microcantilevers", Appl. Phys. Lett. vol. 66, p. 1695, 1995.
  12. A.V. Churenkov, "Photothermal excitation and selfexcitation of silicon microresonators", Sensors and Actuators A: Physical, vol. 39, pp.141-148, 1993. https://doi.org/10.1016/0924-4247(93)80211-X

Cited by

  1. A Polysilicon Field Effect Transistor Pressure Sensor of Thin Nitride Membrane Choking Effect of Right After Turn-on for Stress Sensitivity Improvement vol.23, pp.2, 2014, https://doi.org/10.5369/JSST.2014.23.2.114
  2. Development of a Low-cost Automatic Water Quality Diagnosis System for Cooling Towers vol.23, pp.1, 2014, https://doi.org/10.5369/JSST.2014.23.1.58