Development of quantum dot aptasensor and its portable analyzer for the detection of di-2-ethylhexyl phthalate

Hyun Jeong Lim, A. Ru Kim, Moon Young Yoon, Youngmin You, Beelee Chua, Ahjeong Son

Research output: Contribution to journalArticle

4 Citations (Scopus)


We have developed a quantum dot aptasensor (QD-aptasensor) and its accompanying portable analyzer for the detection of di-2-ethylhexyl phthalate (DEHP). This sensor is based on a newly screened aptamer (60-mer) via SELEX and shows a binding affinity of 213 nmol/L with DEHP. The 60-mer aptamer together with its three shorter truncated aptamers (45, 28, and 22-mer) as well as three different DNA probes (12, 9, and 13-mer) were further investigated to form the best combination for the QD-aptasensor. Using a 22-mer-truncated aptamer and a 12-mer DNA probe combination, the QD-aptasensor demonstrated excellent DEHP sensitivity with an LOQ = 0.5 pg/mL as well as good selectivity in the presence of other phthalate analogs. The binding between the truncated aptamers and DEHP was also characterized. Finally, a QD-aptasensor-based portable analyzer was also developed, and its equivalence to the laboratory protocol was established with a correlation coefficient r = 0.86 for DEHP concentrations ranging from 0.0005 to 100 ng/mL.

Original languageEnglish
Pages (from-to)1-9
Number of pages9
JournalBiosensors and Bioelectronics
Publication statusPublished - 2018 Dec 15



  • Aptamer
  • Di-2-ethylhexyl phthalate
  • Portable analyzer
  • Quantum dot aptasensor

ASJC Scopus subject areas

  • Biotechnology
  • Biophysics
  • Biomedical Engineering
  • Electrochemistry

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