Characterization of quantum dots using capillary zone electrophoresis

✍ Scribed by Mark Pereira; Edward P. C. Lai; Bryan Hollebone

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 368 KB
• Volume: 28
• Category: Article
• ISSN: 0173-0835
• DOI: 10.1002/elps.200600737

✦ Synopsis

Abstract

Commercially available quantum dots (QDs) were characterized using CE. The CE instruments were laboratory‐built, each being capable of both electrokinetic and hydrodynamic injection. Modes of detection include UV absorption and LIF. The CE‐LIF system was further modified to handle microliter sample volumes during injection. Sodium phosphate (5–25 mM, pH 7.5–11) was found to be a good buffer electrolyte. Sodium mercaptoproprionate CdTe/CdS (ADS620) QDs and carboxylic acid CdSe/ZnS (T2‐Evitag) QDs yielded high separation efficiencies of N = 1.5×10^6^ plates at t~M~ = 10 min and N = 1.0×10^5^ plates at t~M~ = 3.8 min, respectively. Apparently the EDC/sulfo‐NHS bioconjugation chemistry worked well with the neutral T2‐Evitag QDs, but not so well with the negatively charged ADS620 QDs. This preliminary knowledge will serve as a basis for new CE immunoassay studies of QD‐biomolecule conjugates and their immunocomplexes with target analytes.