Capacitive biosensor for identifying a microorganism or determining antibiotic susceptibility

Abstract

An apparatus for inspecting an antibiotic and a method for determining antibiotic sensitivity using the same is provided. The antibiotic susceptibility inspection time which has conventionally taken longer than 24 hours is shortened to about 2 hours or less, the efficacy of the target substance is monitored in real time, the identification of the microorganism, the kind of the antibiotic capable of treating the microorganism, and the minimum dosage thereof are quickly confirmed. Microbial infections requiring prompt diagnosis and treatment can be effectively treated.

What is claimed is: 
     
         1 . A copacitive bioseneor for identifying a microorganism or determining an antibiotic susceptibility of the microorganism, the copacitive bioseneor comprising:
 a substrate including an anodic aluminum oxide;   an electrode layer formed on the substrate and including an interdigitated first electrode and an interdigitated second electrode; and   an aptamer fixed to the substrate and specifically bound to the microorganism.   
     
     
         2 . The copacitive bioseneor of  claim 1 , wherein the anodic aluminum oxide is formed by:
 i) anodizing an aluminum surface with acid treatment; and   ii) extending a porous nanostructure.   
     
     
         3 . The copacitive bioseneor of  claim 1 , wherein the fixing is accomplished through a bond between a —COOH group introduced on a surface of the anodic aluminum oxide and a —NH 2  group of the aptamer. 
     
     
         4 . The copacitive bioseneor of  claim 3 , wherein the —COOH group introduced on the surface of the anodic aluminum oxide is formed by:
 i) introducing a —OH group by treating the surface of the anodic aluminum oxide with an O 2  plasma; 
 ii) introducing a —NH 2  group by treating 3-aminopropyltriethoxysilane (APTES) on the surface of the anodic aluminum oxide on which the —OH group is introduced; and 
 iii) introducing a —COOH group by treating on the surface of the anodic aluminum oxide on which the —NH 2  group with succinic anhydride. 
 
     
     
         5 . The copacitive bioseneor of  claim 1 , wherein a distance between the first electrode and the second electrode is 1 μm to 100 μm. 
     
     
         6 . The copacitive bioseneor of  claim 1 , wherein the aptamer is fixed between the first electrode and the second electrode. 
     
     
         7 . The copacitive bioseneor of  claim 1 , the copacitive bioseneor further comprises a storage portion capable of receiving at least one of an electrode layer, an antibiotic, and a microorganism therein. 
     
     
         8 . The copacitive bioseneor of  claim 1 , wherein the microorganism is a bacterium. 
     
     
         9 . The copacitive bioseneor of  claim 8 , wherein the bacterium is a gram-positive bacterium, a gram-negative bacterium, or an antibiotic resistant bacterium of at least one thereof. 
     
     
         10 . The copacitive bioseneor of  claim 1 , wherein the antibiotic is selected from the group consisting of a Gentamicin, a Tetracycline, an Ampicillin, an Erythromycin, a Vancomycin, a Linezolid, a Methicillin, an Oxacillin, a Cefotaxime, a Rifampicin, an Amikacin, a Kanamycin, a Tobramycin, a Neomycin, an Ertapenem, a Doripenem, a Imipenem/a Cilastatin, a Meropenem, a Ceftazidime, a Cefepime, a Ceftaroline, a Ceftobiprole, an Aztreonam, a Piperacillin, a Polymyxin B, a Colistin, a Ciprofloxacin, a Levofloxacin, a Moxifloxacin, a Gatifloxacin, a Tigecycline, and combinations and derivatives thereof. 
     
     
         11 . The copacitive bioseneor of  claim 1 , wherein the copacitive bioseneor identifies the microorganism by determining a change in capacitance in real time caused by coupling of the microorganism to the copacitive bioseneor, or determines a change in capacitance in real time caused by separation or deformation of the microorganism from the aptamer by the antibiotic. 
     
     
         12 . A method for determining an antibiotic susceptibility of a microorganism, the method comprising:
 binding the microorganism to the copacitive bioseneor as claimed in  claim 1 ;   treating the microorganism-bound copacitive bioseneor with an antibiotic; and   determining a change in capacitance after the antibiotic treatment.   
     
     
         13 . A method for identifying a microorganism, the method comprising:
 treating a sample containing a microorganism in the copacitive bioseneor as claimed in  claim 1 ;   confirming whether the microorganism in the sample and the aptamer are bound to each other by determining a capacitance change after the sample treatment; and   identifying the microorganism.