1 research outputs found
Omnidispersible Hedgehog Particles with Multilayer Coatings for Multiplexed Biosensing
Hedgehog particles (HPs) replicating
the spiky geometry of pollen
grains revealed surprisingly high dispersion stability regardless
of whether their hydrophobicity/hydrophilicity matches that of the
media or not. This property designated as omnidispersibility is attributed
to the drastic reduction of van der Waals interactions between particles
coated with stiff nanoscale spikes as compared to particles of the
same dimensions with smooth surfaces. One may hypothesize but it remains
unknown, however, whether HPs modified with polymers or nanoparticles
(NPs) would retain this property. Surface modifications of the spikes
will expand the functionalities of HPs, making possible their utilization
as omnidispersible carriers. Here, we show that HPs carrying dense
conformal coatings made by layer-by-layer (LBL/LbL) assembly maintain
dispersion stability in environments of extreme polarity and ionic
strength. HPs, surface-modified by multilayers of polymers and gold
NPs, are capable of surface-enhanced Raman scattering (SERS) and overcome
the limited colloidal stability of other SERS probes. The agglomeration
resilience of HPs leads to a greater than one order of magnitude increase
of SERS intensity as compared to colloids with smooth surfaces and
enables simultaneous detection of several targets in complex media
with high ionic strength. Omnidispersible optically active colloids
open the door for rapid multiplexed SERS analysis in biological fluids
and other applications