Category Archives: Analytical trap

From a for atto to z for zepto

Todays detection limits are very low. Using various methods such as amperometric detection [1], surface plasmon resonance [2], and laser–induced fluorescence detection [3] it is possible to sense few attomolar (10-18 mol·L-1) concentrations of analytes.

Continue reading

References

  1. W. Gao, H. Dong, J. Lei, H. Ji, and H. Ju, "Signal amplification of streptavidin–horseradish peroxidase functionalized carbon nanotubes for amperometric detection of attomolar DNA", Chemical Communications, vol. 47, pp. 5220, 2011. http://dx.doi.org/10.1039/C1CC10840A
  2. J. Ferreira, M.J.L. Santos, M.M. Rahman, A.G. Brolo, R. Gordon, D. Sinton, and E.M. Girotto, "Attomolar Protein Detection Using in-Hole Surface Plasmon Resonance", Journal of the American Chemical Society, vol. 131, pp. 436-437, 2009. http://dx.doi.org/10.1021/ja807704v
  3. D.B. Craig, J.C.Y. Wong, and N.J. Dovichi, "Detection of Attomolar Concentrations of Alkaline Phosphatase by Capillary Electrophoresis Using Laser-Induced Fluorescence Detection", Analytical Chemistry, vol. 68, pp. 697-700, 1996. http://dx.doi.org/10.1021/ac950650z

ICP-OES: Why spectral lines are true peaks and how this can fool the user.

ICP–OES is a common technique in analytical chemistry, which is characterized by simplicity, simultaneous multi-elemental determination capability, high sensitivity, linear dynamic range, low detection limits, and good precision [1]. It seems to be the perfect method for element analysis (esp. metals). However, sometimes it can fool the user.

Continue reading

References

  1. K. Satyanarayana, and S. Durani, "Separation and inductively coupled plasma optical emission spectrometric (ICP-OES) determination of trace impurities in nuclear grade uranium oxide", Journal of Radioanalytical and Nuclear Chemistry, vol. 285, pp. 659-665, 2010. http://dx.doi.org/10.1007/s10967-010-0591-8