A dual-mode
functional chip for chiral sensing based on mobile
phone wettability measurements and portable surface-enhanced Raman
spectroscopy (SERS) is reported. The plasmon-active regular gold grating
surface was covalently grafted with chiral recognition moieties, l- or d-enantiomers of tartaric acid, making stereoselective
discrimination of chiral amines possible. Chiral sensing of amines
includes two modes of analysis, performed subsequently on the one
chip surface with portable instruments (mobile phone equipped with
a camera and developed application (app) Dropangle and a portable Raman spectrometer). First, the wettability changes,
caused by enantioselective entrapping of chiral amines, are monitored
and analyzed via our mobile phone app, allowing detection of the optical
configuration and concentration of enantiomers with 1 order of magnitude
accuracy. Second, SERS measurement on the same chip provides information
about the chemical structure of entrapped amines and allows calculation
of the enantiomeric excess with great accuracy. The applicability
of the developed chip is demonstrated on a variety of chiral amines,
including tyrosine, cysteine, dopamine (DOPA), and dextromethorphan
in analytical solutions and in commercially available DOPA-containing
drug. Moreover, we demonstrate that the chips could be regenerated
and used repeatedly for at least five cycles.
The efficient utilization
of solar energy is the actual task of
the present and near future. Thus, the preparation of appropriate
materials that are able to harvest and utilize the broad wavelength
range of solar light (especially commonly ignored near-infrared light
regionNIR) is the high-priority challenging mission. Our study
provides a rationally designed two-dimensional (2D) flexible heterostructures
with photocatalytic activity for the production of “clean”
hydrogen under NIR illumination, with the hydrogen production rate
exceeding most 2D materials and the ability to use the seawater as
a starting material. The proposed design utilizes the hybrid bimetallic
(Au/Pt) periodic structure, which is further covalently grafted with
a metal–organic framework MIL-101(Cr). The periodic gold structure
is able to efficiently support the plasmon-polariton wave and to excite
the hot electrons, which is further injected in the Pt and MIL-101(Cr)
layers. The Pt and MIL-101(Cr) structures provide catalytic sites,
which are saturated with hot electrons and efficiently initiate water
splitting and hydrogen production. The MIL-101(Cr) layer also serves
for repelling generated hydrogen bubbles. The mechanistic studies
reveal the catalytic role of every element of the 2D flexible heterostructures.
The maximum hydrogen output was achieved under plasmon resonance excitation
in the NIR range, and it could be actively controlled by the applied
LED wavelength.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.