Like a smart highlighter, immunofluorescent labeling can zero in on a specific protein, helping scientists understand the structure of a cell and how diseases affect that structure. Current techniques have disadvantages, though.
Scientists developed a non-toxic, organic nanoparticle for immunofluorescent labeling that makes a bright, longer-lasting glow. “We’ve demonstrated the promising application of organic nanoparticles for immunofluorescent labeling,” says Jinsang Kim, assistant professor of materials science and engineering who is the principal investigator. “Our molecules show unique properties. When they clump together, they get brighter, the opposite of what normally happens.”
Immunofluorescent labeling works like this: Scientists join fluorescent particles with protein-seeking molecules and let the companions loose in cells to bind to the protein they want to locate and study. The scientists then radiate the mixture with ultraviolet light. The light causes the fluorescent particles to glow, giving away the location of the protein.
Certain diseases can change the amount of particular proteins in cells. Prostate tumors, for example, can increase the level of prostate-specific antigen, which is a cellular protein.
For fluorescent particles, scientists currently can choose between organic fluorescent dyes and inorganic quantum dots, both of which have shortcomings: dyes wear out easily from the ultraviolet light and inorganic quantum dots are toxic.
Kim’s nanoparticles bridge the gap between these methods. They’re non-toxic, and the researchers’ novel way of making the nanoparticles causes them to shine brightly without deteriorating as easily as organic dyes.
Jinsang is an assistant professor of chemical engineering, macromolecular science, and engineering and biomedical engineering. Additional authors include Hyong-Jun Kim, research fellow in materials science and engineering, and Jiseok Lee, a graduate student in macromolecular science and engineering.
