Facile Counting of Ligands Capped on Nanoparticles via a Titration Chip of Moving Reaction Boundary Electrophoresis

Qiang Zhang; Weiwen Liu; Muhammad Idrees Khan; Cunhuai Wang; Guoqing Li; Hua Xiao; Yuxing Wang; Chengxi Cao

doi:10.1021/acs.analchem.9b01098

Facile Counting of Ligands Capped on Nanoparticles via a Titration Chip of Moving Reaction Boundary Electrophoresis

Anal Chem. 2019 Jun 18;91(12):7500-7504. doi: 10.1021/acs.analchem.9b01098. Epub 2019 Jun 4.

Authors

Qiang Zhang^{1

2

3}, Weiwen Liu², Muhammad Idrees Khan^{1

2

3}, Cunhuai Wang^{1

2

3}, Guoqing Li^{1

2

3}, Hua Xiao³, Yuxing Wang⁴, Chengxi Cao^{1

2

3}

Affiliations

¹ Shanghai Sixth People's Hospital East , Shanghai Jiao Tong University Medical School , Shanghai 201306 , China.
² Department of Instrument Science and Engineering, School of Electronic Information and Electrical Engineering , Shanghai Jiao Tong University , Shanghai 200240 , China.
³ School of Life Science and Biotechnology, State Key Laboratory of Microbial Metabolism , Shanghai Jiao Tong University , Shanghai 200240 , China.
⁴ School of Physics and Astronomy , Shanghai Jiao Tong University , Shanghai 200240 , China.

PMID: 31132248
DOI: 10.1021/acs.analchem.9b01098

Abstract

Absolute quantification of ligand capped on the surface of nanoparticles (NPs) has faced a great challenge without the use of complex inner standards (CIS). Herein, we proposed a facile electrophoresis titration (ET) model, designed an ET device, and developed a relevant method for counting the ligand on NPs without the use of CIS, based on moving reaction boundary (MRB). Furthermore, we conducted the relevant ET runs by using 3-mercaptopropionic acid (MPA) and quantum dots (QDs) as the model ligand and NPs, respectively. The experiments revealed that the ligand content of 1518 ± 295 obtained via an ET was close to the one of 1408 ± 117 determined via NMR, validating the ET model. Moreover, the experiments showed fair stability (RSD < 5.62%) and simplicity of ET without the use of CIS. Evidently, the ET model opens a window for facile assay of ligand capped on NPs.

Publication types

Research Support, Non-U.S. Gov't