High throughput detection of fusion proteins

Abstract

A method and related microfluidic chip and kit for high throughput detection of proteins of interest contained in a sample is disclosed. The method comprises of specifically labeling fusion proteins in a complex sample with fusion tag specific fluorophores that specifically bind the fusion tags coupled to the proteins of interest, and subjecting the sample to automated capillary electrophoresis, wherein the presence of the proteins of interest in the sample is detected by fluorescence signals associated with the fusion tag specific fluorophores.

We claim: 
     
         1 . A kit comprising:
 (a) a microfluidic chip adapted for use in a method of high throughput detection of proteins of interest contained in a sample, wherein the method comprises:
 (i) contacting a sample not subjected to prior purification comprising contaminating proteins without fusion tags and affinity tagged fusion proteins of interest to a plurality of fluorescent labels having specificity for the affinity tags, wherein, upon contacting, fluorescent labels covalently bind the affinity tags to form detectable protein complexes; 
 (ii) subjecting the contacted sample to microfluidic electrophoresis, wherein the presence of the proteins of interest but not contaminating proteins in the contacted sample is detected by fluorescence signals associated with the affinity tags; 
   (b) a fusion tag specific fluorophore; and   (c) a means for detection, wherein the presence of the proteins of interest in the sample is detected by fluorescence signals associated with the fusion tag specific fluorophores.   
     
     
         2 . The kit of  claim 1 , wherein the fusion tag specific fluorophore has an excitation and emission maxima near about 635 nm and about 700 nm, respectively. 
     
     
         3 . The kit of  claim 1 , wherein the sample not subjected to prior purification is a cell lysate. 
     
     
         4 . The kit of  claim 1 , wherein the sample not subjected to prior purification is a bacterial cell lysate.