Related Experiment Video
Updated: Feb 5, 2026

Collection of Alfalfa Root Exudates to Study the Impact of Di2-ethylhexyl Phthalate on Metabolite Production
Published on: June 2, 2023
Development of quantum dot aptasensor and its portable analyzer for the detection of di-2-ethylhexyl phthalate
Hyun Jeong Lim1, A-Ru Kim2, Moon-Young Yoon2
1Department of Environmental Science and Engineering, Ewha Womans University, 52 Ewhayeodae-gil, Seodaemun-gu, Seoul 03760, Republic of Korea.
Abstract:
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.
Related Concept Videos
Quantum Numbers
The Quantum-Mechanical Model of an Atom
Piaget's Stage 2 of Cognitive Development
The Dot Product
Dot Product
In engineering, the dot product of any two vectors is the product of the magnitudes of the vectors and the cosine of the angle between them. It is denoted by a dot symbol between the two vectors.
Consider a vehicle pulling an object along the ground using a rope. If the rope makes an angle with the horizontal axis, the work done can be calculated using the dot product of the force applied and the object's displacement.
The dot...
Dot Product: Problem Solving
Identify the problem: Start by reading the problem and...

