International Journal of
Physical Sciences

  • Abbreviation: Int. J. Phys. Sci.
  • Language: English
  • ISSN: 1992-1950
  • DOI: 10.5897/IJPS
  • Start Year: 2006
  • Published Articles: 2557

Full Length Research Paper

Using two-photon excitation methods for determination of Ca2+ in contamination with protein

A. S. M. Noor1*, A. Miyakawa2, W. Inami3 and Y. Kawata2
  1Wireless and Photonics Network Centre of Excellent (WiPNet), Department of Computer and Communication System Engineering, Faculty of Engineering, Universiti Putra Malaysia, 43400 UPM Serdang, Malaysia. 2Department of Mechanical Engineering, Faculty of Engineering, Shizuoka University, Johoku 3-5-1, Naka-ku, Hamamatsu, Shizuoka 432-8561, Japan. 3Division of Global Research Leaders, Shizuoka University, Johoku 3-5-1, Naka-ku, Hamamatsu, Shizuoka 432-8561, Japan.
Email: [email protected]

  •  Accepted: 08 September 2011
  •  Published: 09 December 2011



Three emission wavelengths from two-photon excitation techniques were use to determinefree Ca2+ using a new analytical calculation. This was achieved by considering theinteraction of protein with free Ca2+ and indo-1 in protein contaminated sample. The emissions obtained from the excitation with the dissociation constants were used in the calculation. Agreement values of the Ca2+ from the calculation with the known Ca2+ buffer solution used for the measurement was obtained for various Ca2+ and protein concentration. The analytical analysis shows that dissociation constants for each binding’sdeviation errors are small to affect free Ca2+ determination. This would provide an accurate measurement of free Ca2+ in biological cells than the typical two emission wavelength processes. Furthermore, using two-photon excitation methods, deep inside cells observation of free Ca2+ are possible using the methods introduced.


Key words: Free Ca2+, indo-1, two-photon excitation methods.