Study of Streptavidin-Modified Quantum Dots by Capillary Electrophoresis

• DOI: 10.1007/s10337-012-2372-8
• Publication Date: 2012-12-24T07:03:25Z
• Authors: Maja Stanisavljevic; Libor Janu; Kristyna Smerkova; Sona Krizkova; Nadezda Pizurova; Marketa Ryvolova; Vojtech Adam; Jaromir Hubalek; Rene Kizek
• Keywords: 02 engineering and technology; 0210 nano-technology

Great boom of nanotechnologies impacts almost all areas of science and therefore detail understanding of the properties of nanomaterials as well as their interaction abilities is required. Surface modification and functionalization of nanoparticles is of a great interest due to the wide range of applications in the area of nanomedicine, nanobiology, and/or biochemistry. In this study, CdTe QDs were synthesized using microwave reactor and their surface was modified by streptavidin to ensure further suitability for bioconjugation with biotin-labelled oligonucleotides. For characterization of the synthesized QDs and for monitoring of the interaction with the oligonucleotide, capillary and gel electrophoresis was used. Moreover, complementary advantages of absorption (CE–UV) and laser-induced fluorescence detection (CE–LIF) were exploited. Comparison the electrophoretic mobilities obtained for streptavidin-modified QDs by CE–LIF (−9.87 × 10−9 m2/V/s) and by CE–UV (−10.02 × 10−9 m2/V/s) was in a good agreement enabling us to identify the peak of streptavidin-modified QDs in the CE–UV electropherogram containing also the peak of unreacted streptavidin. Subsequent conjugation of streptavidin-modified QDs with two model biotinylated oligonucleotides (BCL-2 and HBV) led to formation of the complex represented in the electropherograms as a very sharp peak. This peak height increased with time for 15.5 and 27 mAU using BCL-2 oligonucleotide and HBV oligonucleotide, respectively during 30 min interaction.