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Updated: Jun 13, 2026
Production and Targeting of Monovalent Quantum Dots
Published on: October 23, 2014
Pyrenebutyrate Leads to Cellular Binding, Not Intracellular Delivery, of Polyarginine-Quantum Dots
Amy E Jablonski1, Takashi Kawakami, Alice Y Ting
1Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139; School of Chemistry and Biochemistry and Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332.
Abstract:
The intracellular, cytosolic, delivery of quantum dots is an important goal for cellular imaging. Recently, a hydrophobic anion, pyrenebutyrate had been proposed to serve as a delivery agent for cationic quantum dots as characterized by confocal microscopy. Using an extracellular quantum dot quencher, QSY-21, as an alternative to confocal microscopy, we demonstrate that quantum dots remain on the cell surface and do not cross the plasma membrane following pyrenebutyrate treatment, a result that is confirmed with transmission electron microscopy. Pyrenebutyrate leads to increased cellular binding of quantum dots rather than intracellular delivery. These results characterize the use of QSY-21 as a quantum dot quencher and highlight the importance of the use of complementary techniques when using confocal microscopy.
