Abstract:
:Fluorescent labels are often used in bioassays as a means to detect and characterize ligand-receptor binding. This is due in part to the inherently high sensitivity of fluorescence-based technology and the relative accessibility of the technique. There is often little concern raised as to whether or not the fluorescent label itself affects the ligand-receptor binding dynamics and equilibrium. This may be particularly important when considering nanoparticle labels. In this study, we examine the affects of nanoparticle (quantum dots and polymer nanospheres) fluorescent labels on the streptavidin-biotin binding system. Since the nanoparticle labels are larger than the species they tag, one could anticipate significant perturbation of the binding equilibrium. We demonstrate, using fluorescence cross-correlation spectroscopy, that although the binding equilibria do change, the relative changes are largely predictable. We suggest that the nanoparticles' mesoscopic size and surface tension effects can be used to explain changes in streptavidin-biotin binding.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Swift JL,Cramb DTdoi
10.1529/biophysj.107.127688subject
Has Abstractpub_date
2008-07-01 00:00:00pages
865-76issue
2eissn
0006-3495issn
1542-0086pii
S0006-3495(08)70261-3journal_volume
95pub_type
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