Uniform Core–Shell Photonic Crystal Microbeads
as Microcarriers for Optical Encoding
Xiaolu Jia
Yuandu Hu
Ke Wang
Ruijing Liang
Jingyi Li
Jianying Wang
Jintao Zhu
10.1021/la502858f.s001
https://acs.figshare.com/articles/journal_contribution/Uniform_Core_Shell_Photonic_Crystal_Microbeads_as_Microcarriers_for_Optical_Encoding/2245945
We demonstrate a rapid and robust
method to fabricate uniform core–shell
photonic crystal (PC) microbeads by the microfluidic and centrifugation–redispersion
technique. Colored crystalline colloidal arrays (CCAs) were first
prepared through centrifugation–redispersion approach by self-assembly
of polystyrene–poly(<i>N</i>-isopropylacrylamide)
(PS–PNIPAm) core/shell nanoparticles (NPs). Different from
the conventional NPs (e.g., charged PS or PNIPAm NPs), PS–PNIPAm
NPs could easily self-assemble into well-ordered CCAs by only one
purification step without laborious pretreatment (e.g., dialysis or
ion exchange) or slow solvent-evaporation process. The CCAs is then
encapsulated into a transparent polymer shell with functional groups
(e.g., copolymer of ETPTA and butyl acrylate (BA)), triggering the
formation of core–shell PC microbeads which can be used as
optical encoding microcarriers. Importantly, this technique allows
us to produce core–shell PC microbeads in a rapid and robust
way, and the optical reflections of the PC microbeads appear highly
stable to various external stimuli (e.g., temperature, pH value, and
ionic strength) relying on the features of the CCAs core and protection
of the polymer shell. Moreover, various probe biomolecules (e.g.,
proteins, antibodies, and so on) can be easily linked on the surface
of the core–shell PC microbeads owing to the hydrophilic modification
induced by the hydrolysis of BA on the microbead surface, enabling
the multiplex biomolecular detection.
2014-10-14 00:00:00
BA
polymer shell
CCA
PS
PC
core
e.g
NP
ETPTA
microbead
multiplex biomolecular detection