Preliminary Advancement for an Electrochemical Biosensor for Early Diagnosis of Alpha-1-Antitrypsin Deficiency

Abstract

Electrochemical  biosensors  present  a  potential  advance  in  the  field  of  disease diagnosis  by  providing  immediate  and  accurate  results  in  the  detection  of  pre-specified targets. In most cases, the successful diagnosis and treatment of diseases is reliant  upon  out-of-date  testing  instruments  that  are  no  longer  adequate.    For  this reason,  it  is  important  to  explore  the  novel  combination  of  established  testing methods  with  modern  technology.    For  the  case  of  alpha-1-antitrypsin  (A1AT) deficiency  (A1AD),  a  complete  diagnosis  currently  requires  a  minimum  of  three individual tests performed using blood serum.  The use of a specialized biosensor to detect a deficiency and the form of A1AT could potentially have a dramatic increase in   diagnosing   carriers   of   genetic   mutations   in   the   A1AT   gene   sequence   that predispose them to early-onset emphysema. The use of an electrochemical biosensor could replace the need for all three of these tests  within  one  instrument.    The  biosensor  would  incorporate  an electrochemical quartz   crystal   nanobalance   (EQCN)   with   an   electrode   surface   that   has   been functionalized  with  a  biological  agent  that  would  bind  to  an  analyte  that  confirms A1AD.    A  visual  representation  of  the  electrode  surface  is  provided  in  Figure  1  for the  binding  of  an  analyte  on  the  functionalized  gold  surface.   Lomant’s  Reagent, dithiobis(succinimidyl propionate) (DSP), has been used in several other biosensors to functionalize the gold surface of the electrode (4).  DSP is a preferred reagent due to  the  functionality  provided  by  the  carboxyl  group  as  well  as  the  length  of  the carbon backbone.Electrochemical  biosensors  present  a  potential  advance  in  the  field  of  disease diagnosis  by  providing  immediate  and  accurate  results  in  the  detection  of  pre-specified targets. In most cases, the successful diagnosis and treatment of diseases is reliant  upon  out-of-date  testing  instruments  that  are  no  longer  adequate.    For  this reason,  it  is  important  to  explore  the  novel  combination  of  established  testing methods  with  modern  technology.    For  the  case  of  alpha-1-antitrypsin  (A1AT) deficiency  (A1AD),  a  complete  diagnosis  currently  requires  a  minimum  of  three individual tests performed using blood serum.  The use of a specialized biosensor to detect a deficiency and the form of A1AT could potentially have a dramatic increase in   diagnosing   carriers   of   genetic   mutations   in   the   A1AT   gene   sequence   that predispose them to early-onset emphysema.

The use of an electrochemical biosensor could replace the need for all three of these tests  within  one  instrument.    The  biosensor  would  incorporate  an electrochemical quartz   crystal   nanobalance   (EQCN)   with   an   electrode   surface   that   has   been functionalized  with  a  biological  agent  that  would  bind  to  an  analyte  that  confirms A1AD.    A  visual  representation  of  the  electrode  surface  is  provided  in  Figure  1  for the  binding  of  an  analyte  on  the  functionalized  gold  surface.   Lomant’s  Reagent, dithiobis(succinimidyl propionate) (DSP), has been used in several other biosensors to functionalize the gold surface of the electrode (4).  DSP is a preferred reagent due to  the  functionality  provided  by  the  carboxyl  group  as  well  as  the  length  of  the carbon backbone.