ac7b00206_si_001.pdf (1.22 MB)
Extracting the Shape and Size of Biomolecules Attached to a Surface as Suspended Discrete Nanoparticles
journal contribution
posted on 2017-03-10, 00:00 authored by Dimitra Milioni, Achilleas Tsortos, Marisela Velez, Electra GizeliThe
ability to derive information on the conformation of surface
attached biomolecules by using simple techniques such as biosensors
is currently considered of great importance in the fields of surface
science and nanotechnology. Here we present a nanoshape sensitive
biosensor where a simple mathematical expression is used to relate
acoustic measurements to the geometrical features of a surface-attached
biomolecule. The underlying scientific principle is that the acoustic
ratio (ΔD/ΔF) is a measure
of the hydrodynamic volume of the attached entity, mathematically
expressed by its intrinsic viscosity [η]. A methodology is presented
in order to produce surfaces with discretely bound biomolecules where
their native conformation is maintained. Using DNA anchors we attached
a spherical protein (streptavidin) and a rod-shaped DNA (47bp) to
a quartz crystal microbalance (QCM) device in a suspended way and
predicted correctly through acoustic measurements their conformation,
i.e., shape and length. The methodology can be widely applied to draw
conclusions on the conformation of any biomolecule or nanoentity upon
specific binding on the surface of an acoustic wave device.