The Investigation of Value Added Applications of Paper Products in Areas of Bio-separations and Bio-detections by Nimesh Patel & Dr. Michael Mason

One rapidly growing area of research involves the investigation of value added applications of paper products in areas of bio-separations and bio-detections. These novel systems are now being referred to as “bio-active paper”. One potential future application of this paper is in Biological Warfare Agents (BWA) and infectious diseases (ID) detection. At this point, there are two ways in which to do this. One is by using Polymerase Chain Reaction to amplify the sample in a laboratory. The advantage of this is reliability and specificity. However, it has drawbacks of being time consuming and expensive. The other method of detection includes the types used in the field, which work similar in a manner to pregnancy tests in the sense of an almost immediate response. The drawbacks to these is that they are not able to distinguish between similar pathogens that exhibit large variance in toxicity (not specific) nor are they able to detect certain BWA/ID in trace, yet harmful, concentrations. These drawbacks can lead to false positives and false negatives. Thus, the overall long-term goal of the research is to use the production of bio-active paper along with chemistry to develop a field detection system that is cost-effective, fast, and accurate.

To do this we will employ a bio-chemical amplification technique using enzymes. The process begins with a molecular beacon that will be engineered down to a specific base on the DNA of the sample to ensure selectivity. If there is an exact match, the hairpin shaped DNA that is attached to the inhibitor of the enzyme will uncoil. This will release the inhibitor and allow the enzyme to start a chemical reaction. We will use a lipase to produce H+ ions. These H+ ions will be used to activate an indicator molecule or dye that will show the presence of the specific pathogen.

The current specific research will deal with maximizing the efficiency of detection not just in solution but on bio-active paper as well. The preliminary unit of this efficiency is: Signal photons (dye) / (time x [enzyme]).

To do this we will have to choose the proper dye that will show the best on the paper in the correct pH of the reaction. In addition, since no two enzyme molecules are alike, there is the variable of different enzyme molecules within an ensemble of similar enzymes that can sometimes produce different results. Consequently, we must find what aspects of the single enzyme molecule optimize the amount of signal photons.

Once the enzyme has been selected and characterized at the sub-ensemble level and also the dye indicator system selected, then device geometries that involve bio-active paper loading will be investigated. Specifically, the “on paper” enzyme activity and dye sensitivity will be compared to data obtained from the solution and ensemble measurements.

Finally, after the first two stages, there is further research to be done on creating an H+ permeable membrane to remove the excess H+ from the system so it does not slow down the reaction according to Le Chatelier’s principle by fueling the reverse reaction.

REU Interview 07/11/07

http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/2007FBRI/nimesh.m4a