Electrical cell-substrate impedance sensor (ecis)

Abstract

A method for detection and monitoring a therapeutic effect of a cancer treatment drug is disclosed. The method includes steps of removing a malignant biological cell lines from a tumor; culturing the removed biological cell lines in a controlled set of conditions; seeding the cultured biological cell lines on silicon nanowire electrode arrays of an electrical cell-substrate impedance sensor (ECIS); adding a cancer treatment drug to the seeded biological cell lines to treat the seeded biological cell lines; and measuring an electrical impedance of the treated biological cell lines for detection and monitoring a therapeutic effect of the cancer treatment drug.

1 - 28 . (canceled) 
     
     
         29 . A method for detection and monitoring a therapeutic effect of a cancer treatment drug, the method comprising steps of:
 growing a layer of silicon dioxide on a substrate layer;   coating one or more portions of the grown silicon dioxide layer with a catalyst layer, wherein one or more portions of the grown silicon dioxide layer are not coated with the catalyst layer, thereby patterning the catalyst layer to form a sensor region on the substrate layer;   selectively growing a plurality of silicon nanowire electrode arrays on the portions of the silicon dioxide layer that have been coated with the catalyst layer and forming an electrical cell-substrate impedance sensor (ECIS);   seeding cultured biological cells onto a surface of the grown silicon nanowire electrode arrays such that the biological cells become attached to the silicon nanowire electrode arrays;   adding the cancer treatment drug to the seeded biological cell lines; and   measuring an electrical impedance of the treated biological cells for detection and monitoring of a therapeutic effect of the cancer treatment drug,   
     
     
         28 . The method according to  claim 29 , wherein adding the treatment drug includes:
 adding a specific amount of the treatment drug to the biological cells that are attached to the silicon nanowire electrode arrays, and   maintaining the biological cells with the added treatment drug in an incubator for a specific time interval.   
     
     
         31 . The method according to  claim 29 , wherein the biological cells include cells from epithelial cancerous cell lines supplied from a cell bank, a portion of an epithelial cancerous tumor, cells from breast cancerous cell lines, or a portion of a breast cancerous tumor. 
     
     
         32 . The method according to  claim 31 , wherein the epithelial cancerous cell lines include MCF-7 (Michigan Cancer Foundation-7) cell lines. 
     
     
         33 . The method according to  claim 29 , wherein the ECIS is packed in a plexiglass cover and is sealed with a biograde silicon rubber tube. 
     
     
         34 . The method according to  claim 29 , wherein the method further comprises:
 seeding the cultured biological cells by:
 dropping the cultured biological cells on a surface of a packed and sealed ECIS, and 
 maintaining the dropped biological cells in an incubator to achieve attachment between the biological cells and the silicon nanowire electrode arrays of ECIS. 
   
     
     
         35 . The method according to  claim 36 , wherein the biological cells are trypsinized from a surface of a cell flask or a microwell for less than four minutes and at room temperature to detach from the cell flask or the microwell and then are dropped and re-cultured on the silicon nanowire electrode arrays. 
     
     
         36 . The method according to  claim 36 , wherein dropping the cultured biological cells includes dropping the cultured biological cells with a volume of about 300 μl. 
     
     
         37 . The method according to  claim 29 , wherein the cancer treatment drug is an antitubulin drug. 
     
     
         38 . The method according to  claim 29 , wherein measuring the electrical impedance comprises:
 applying a specific voltage to a sensor package with the biological cells attached to the silicon nanowire electrode arrays, and   measuring an electrical impedance of the biological cells attached to the silicon nanowire electrode arrays at various specific frequencies.   
     
     
         39 . The method according to  claim 38 , wherein measuring the electrical impedance is performed about 2 hours and 6 hours after the drug treatment. 
     
     
         40 . The method according to  claim 38 , wherein the applied voltage is about 400 mV. 
     
     
         41 . The method according to  claim 29 , wherein the catalyst layer includes a material of either gold or a bilayer of Ni—Au.