Ultra sensitive microfluidic immunosensor for determination of clenbuterol in bovine hair samples using electrodeposited gold nanoparticles and magnetic micro particles as bioaffinity platform

REGIART DM; FERNÁNDEZ-BALDO MA; SPOTORNO VG; BERTOLINO FA; RABA J

BIOSENSORS & BIOELECTRONICS

ELSEVIER ADVANCED TECHNOLOGY

Lugar: Amsterdam; Año: 2013 vol. 41 p. 211 - 217

0956-5663

In  this  article,  we  report  the  first  integrated  microfluidic  immunosensor  coupled  to  a screen-printed carbon electrode (SPCE) applied to determination of clenbuterol (CLB) in bovine hair samples. CLB is a member of  the ß2-agonist drugs which  is used  in animal production and  is banned  in Argentine and  the European Union. It represents a potential risk and has to be carefully monitored to avoid the illegal use of high amounts of this compound that could result in human food poisoning. In  order  to  perform  the  CLB  detection,  the  SPCE  was  modified  by  gold  nanoparticle (AuNPs) electrodeposition.  Quantitative  determination  of  CLB  was  carried  out  using  a  competitive  indirect immunoassay, method based on the use of anti-CLB antibodies immobilized on magnetic micro particles. The  CLB  present  in  bovine  hair  samples  competes immunologically  with  alkaline  phosphatase  (AP) enzyme?labeled CLB  conjugate  for  the  anti-CLB  specific  antibodies.  Later,  p-aminophenyl  phosphate was converted to p-aminophenol by AP, and the electroactive product was quantified on AuNPs/SPCE at +0.1 V. The  limit of detection  for electrochemical method was 0.008 ng mL-1 and  the  intra- and  inter-assay coefficients of variation were below 6%. This being a veterinary control tool very useful for rapid, sensitive and selective detection of CLB in an ?in vitro? technique.