Adrian A Atherton

Publications (2)3 Total impact

• Article: Ultrasensitive detection of proteins and antibodies by absorption-based laser wave-mixing detection using a chromophore label.

  Mirna M Lopez, Adrian A Atherton, William G Tong
  [show abstract] [hide abstract]
  ABSTRACT: Nonlinear laser wave mixing is presented as an ultrasensitive absorption-based method for the detection of proteins and antibodies using a nonfluorescing chromophore label, Coomassie Brilliant Blue (CBB). The complexes are flowed through a 150-microm (i.d.) capillary cell and detected using a low-power He-Ne laser. The wave-mixing signal is detected after 10 min of room temperature incubation for the antibody complex and after 18 min for the protein complex. All solutions are prepared in an aqueous buffer without the addition of organic modifiers. Concentration detection limits of 3.4 x 10(-19) and 6.4 x 10(-14) M (signal-to-noise ratio [S/N] = 2) are determined for bovine serum albumin (BSA) and human papillomavirus (HPV) antibody, respectively. Based on the small laser probe volume used (i.e., overlap volume of the two input beams), mass detection limits of 1.7 x 10(-22) and 2.6 x 10(-17) mol are determined for BSA and HPV antibody, respectively.
  Analytical Biochemistry 12/2009; 399(2):147-51. · 3.00 Impact Factor
• Article: Optics East

  Mirna M. Lopez, Adrian A. Atherton, William G. Tong
  [show abstract] [hide abstract]
  ABSTRACT: Nonlinear spectroscopy based on multi-photon laser wave mixing is presented as a sensitive analytical technique for rapid detection and imaging of various analytes in microfluidic and microarray devices. Capillary electrophoresis microchips and DNA microarrays offer improved speed of analysis over conventional methods. Laser wave-mixing optical methods offer sensitive detection of small changes in chemical and physical properties. Wave-mixing spectroscopy is especially effective in using small optical path lengths available in microchips. This unusually sensitive optical absorption detection method can keep up with fast changing environments in microfluidic systems. In wave mixing, two laser beams are focused and mixed inside the analyte. The analyte probe volume, i.e., the beam overlap volume, is very small. Hence, it is inherently suitable for interfacing to microchips and microarrays for high spatial resolution analysis. Signal collection is very efficient since the signal is a coherent laser-like beam. The signal has a quadratic dependence on analyte concentration and a cubic dependence on laser power. Hence, one can monitor small changes in signal more effectively and one can use low-power compact lasers efficiently.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
  12/2004;