A selective and regenerable voltammetric aptasensor for determination of homocysteine

作者：Saeed Jaber; Mirzaei Mohammad^*; Torkzadeh Mahani Masoud

来源：Microchimica Acta, 2016, 183(7): 2205-2210.

DOI：10.1007/s00604-016-1852-1

• Bioassay
• Biosensor
• Aptamer
• Aptasensor
• Electrochemical sensor
• Gold electrode
• Differential pulse voltammetry
• Electrochemical impedance

We describe an electrochemical aptasensor for the amino acid homocysteine (hCys). A gold electrode was modified with a highly specific aptamer against hCys (a 66-base DNA oligonucleotide) acting as the recognition probe. The method is highly selective over cysteine and methionine. The effects of accumulation time, type and concentration of accumulation buffer and pH, type and concentration of stripping buffer were studied. Under optimized conditions and a working potential of 1.07 V (vs. Ag/AgCl), the response to hCys is linear in the 0.2 to 10 mu M concentration range. The detection limit is 10 nM, and the relative standard deviation is 3.1 % (at 1 mu M of hCys). The electrode can be regenerated by immersing it into a 3M solution of urea solution. The method was applied to the determination of hCys in (spiked) serum and urine and gave recoveries of 88.5 and 96.5 %, respectively.

• 出版日期2016-7