Detecting Concentration of Analytes with DETECHIP: A Molecular Sensing Array

Hannah Johnke, Gary Batres, Mark Wilson, Andrea E. Holmes, Sharmin Sikich

Department of Chemistry, Doane College, Crete, USA.

DOI: 10.4236/jst.2013.33015                

Abstract

DETECHIP is a detection system made of various sensors that has been shown to detect and discriminate between small molecules of interest, including various illicit and over-the-counter drugs. Previously, detection was normalized to a single concentration of analyte. Now this detection assay can detect concentration differences in analytes via red, green, and blue color value changes and shifts in the UV-Vis spectra of the assay. To determine the concentrations differences, the exposed assays were scanned on a flatbed scanner and the images were analyzed for individual RGB values with a custom macro in ImageJ, an image analysis program. Increasing concentrations of the analyte resulted in greater differences in color values between control and analyte wells. These differences showed a linear relationship to concentration change, some with correlation coefficients greater than 98%. This work expands the capability of DETECHIP to give information about the concentration of analyte when the analyte identity is known.

Keywords

Colorimetric Arrays; Sensors; Analyte Concentration; RGB Analysis; Drug Detection

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	A. Smith, A. Jackson, M. V. Wilson, M. Trauernicht and A. E. Holmes, “Improved Image Analysis of DETECHIP Allows for Increased Specificity in Drug Discrimination,” Journal of Forensic Research, Vol. 3, No. 8, 2012, pp. 1-5. http://dx.doi.org/10.4172/2157-7145.1000161
[2]	M. Lyon, M. V. Wilson, K. A. Rouhier, D. J. Symonsbergen, K. Bastola, I. Thapa, A. E. Holmes, S. M. Sikich and A. Jackson, “Image Analysis of DETECHIP—A Molecular Sensing Array,” Advance in Intelligent and Soft Computing, Vol. 166, 2012, pp. 145-158. http://dx.doi.org/10.1007/978-3-642-30157-5_16
[3]	M. Lyon, M. V. Wilson, K. A. Rouhier, D. J. Symonsbergen, K. Bastola, I. Thapa, A. E. Holmes, S. M. Sikich and A. Jackson, “Digital Image Analysis for DETECHIP Code Determination,” Signal and Image Processing: An International Journal, Vol. 3, No. 4, 2012, pp. 51-63.
[4]	L. Feng, C. J. Musto, J. W. Kemling, S. H. Lim and K. S. Suslick, “A Colorimetric Sensor Array for Identification of Toxic Gases Below Permissible Exposure Limits,” Chemical Communications, Vol. 46, No. 12, 2010, pp. 2037-2039. http://dx.doi.org/10.1039/b926848k
[5]	L. Feng, C. J. Musto and K. S. Suslick, “A Simple and Highly Sensitive Colorimetric Detection Method for Gaseous Formaldehyde,” Journal of the American Chemical Society, Vol. 132, No. 12, 2010, pp. 4046-4047. http://dx.doi.org/10.1021/ja910366p
[6]	K. A. Rakow and K. S. Suslick, “A Colorimetric Sensor Array for Odour Visualization,” Nature, Vol. 406, NO. 6797, 2000, pp. 710-713. http://dx.doi.org/10.1038/35021028
[7]	M. C. Janzen, J. B. Ponder, D. P. Bailey, C. K. Ingison and K. S. Suslick, “Colorimetric Sensor Arrays for Volatile Organic Compounds,” Analytical Chemistry, Vol. 78, No. 11, 2006, pp. 3591-3600. http://dx.doi.org/10.1021/ac052111s
[8]	H. Lin and K. S. Suslick, “A Colorimetric Sensor Array for Detection of Triacetone Triperoxide Vapor,” Journal of the American Chemical Society, Vol. 132, No. 44, 2010, pp. 15510-15521. http://dx.doi.org/10.1021/ja107419t
[9]	R. Burks, S. E. Pacquette, M. A. Guericke, M. V. Wilson, D. J. Symonsbergen, K. A. Lucas, and A. E. Holmes, “DETECHIP?: A Sensor for Drugs of Abuse,” Journal of Forensic Sciences, Vol. 55, No. 3, 2010, pp. 723-727. http://dx.doi.org/10.1111/j.1556-4029.2010.01323.x
[10]	M. Lyon, J. Groathouse, J. Beaber, L. M. Turner, K. A. Rouhier, M. V. Wilson, D. J. Symonsbergen, S. M. Sikich and A. E. Holmes, “DETECHIP: An Improved Molecular Sensing Array,” Journal of Forensic Research, Vol. 2, No. 126, 2012, pp. 1-7.
[11]	S. A. Bergman, “Ketamine: Review of Its Pharmacology and Its Use in Pediatric Anesthesia,” Anesthesia Progress, Vol. 45, No. 1, 1999, pp. 10-20.
[12]	Food Standards Agency, “Aspartame,” 2012. http://www.food.gov.uk/policy-advice/additivesbranch/55174#h_4