System and method for detecting pathogens on treated and untreated substrates using liquid crystal chromonic azo dye

Abstract

Chromonic azo dyes are particular types of chromonic molecules that are alignable homeotropically (aggregated molecules stacked perpendicularly to the surface) on different types of substrates, often without the need of any special surface treatment. This feature enables the optimization of a detection device with increased sensitivity based of the alignment distortion created by a biological immune complex.

What is claimed is: 
     
         1 . A system for detecting pathogens comprising:
 a sealed cell having a preselected thickness and a first axis and a second axis defining a plane;   a pair of opposed substrates positioned within the cell;   a lyotropic chromonic liquid crystal material contained within the cell intermediate the pair of opposed substrates;   a light source adapted to emit a beam of light passing through the cell along an axis substantially perpendicular to the plane;   a pair of linear polarizers, each polarizer being arranged in a cross-polarizing relationship with respect to each other and located adjacent to one of the opposed substrates; and   a light detector adapted to detect any portion of the beam of light which is transmitted through the cell and the polarizers.   
     
     
         2 . The detection system of  claim 1  further including at least one spacer structured and arranged to control the preselected thickness of the cell. 
     
     
         3 . The detection system of  claim 1  further including a receptor mixed into the chromonic liquid crystal material. 
     
     
         4 . The detector system of  claim 3  wherein the receptor comprises an antibody micro-bead and a liquid. 
     
     
         5 . The detection system of  claim 1  wherein each of the substrates comprises uncoated ZEONEX® 350R material. 
     
     
         6 . The detection system of  claim 1  wherein each of the substrates comprises uncoated APEL™ APL5015AL material. 
     
     
         7 . The detection system of  claim 1  wherein each of the substrates comprises a polyimide sheet laminated on glass. 
     
     
         8 . The detection system of  claim 1  wherein each of the substrates comprises glass coated with a HYDROFOE™ super hydrophobic coating. 
     
     
         9 . The detection system of  claim 1  wherein each of the substrates comprises glass coated with KRYLON® crystal clear acrylic material. 
     
     
         10 . The detection system of  claim 1  wherein the lyotropic chromonic liquid crystal material comprises a water solution of chromonic azo dye.