With the support of NIH, Ocean NanoTech has developed a standard bioconjugation protocol to attach nanocrystals to proteins, DNA, and other biomolecules for various applications in the life sciences. One of our approaches involve the use of Protein G in the surface modification of the nanocrystals. Figure 5 shows the gel electrophoresis quantum dots before and after conjugation with protein G. This shows that the larger molecular weight and the lesser amount of charges on the Protein-G conjugated quantum dot resulted in slower migration on the gel. We use gel electrophoresis as one of our quality control processes to assess and monitor the conjugation of various molecules on any of Ocean's nanocrystal.
Another method adopted at Ocean to prepare nanocrystals for bioconjugation is surface modification of the nanocrystals with streptavidin or bovine serum albumin. These proteins coat the outer surface of the nanocrystals allowing for biotin-strepatvidin