Citation: He, Y.; Gao, H.; Liu, J. A
Visible-Light-Active CuS/MoS
2
/
Bi
2
WO
6
Aptamer Sensitively Detects
the Non-Steroidal Anti-Inflammatory
Drug Diclofenac. Nanomaterials 2022,
12, 2834. https://doi.org/10.3390/
nano12162834
Academic Editors: Deepak Kukkar
and Ki-Hyun Kim
Received: 27 June 2022
Accepted: 8 August 2022
Published: 18 August 2022
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4.0/).
Article
A Visible-Light-Active CuS/MoS
2
/Bi
2
WO
6
Aptamer Sensitively
Detects the Non-Steroidal Anti-Inflammatory Drug Diclofenac
Yun He, Hongjie Gao and Jiankang Liu *
The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science
and Technology, Xi’an Jiaotong University, Xi’an 710049, China
* Correspondence: liujiankang2021@hotmail.com
Abstract:
Diclofenac is a non-steroidal, anti-inflammatory drug and is clinically used for the treatment
of osteoarthritis, non-articular rheumatism, etc. This research aimed to demonstrate the creation
of an upgraded photoelectrochemical (PEC) aptamer sensor for detecting diclofenac (DCF) with
high sensitivity. In this work, photoactive materials and bio-identification components served
as visible-light-active CuS/MoS
2
/Bi
2
WO
6
heterostructures and aptamers, respectively. CuS and
MoS
2
/Bi
2
WO
6
were combined to improve photocurrent responsiveness, which helped the structure
of PEC aptasensors. Additionally, the one-pot synthesis of CuS/MoS
2
/Bi
2
WO
6
was ecologically
beneficial. With these optimizations, the photocurrent response of aptamer/CS/CuS/MoS
2
/Bi
2
WO
6
exhibited linearity between 0.1 and 500 nM DCF. The detection limit was 0.03 nM (S/N = 3). These
results suggest that the PEC sensing technique might produce an ultra-sensitive sensor with high
selectivity and stability for DCF detection.
Keywords: photoelectrochemical; CuS/MoS
2
/Bi
2
WO
6
; diclofenac (DFC); heterostructure; aptasensors
1. Introduction
Diclofenac (DCF) is a non-steroidal, anti-inflammatory drug (NSAID) marketed for
global consumption [
1
]. It has been utilized for surgical procedures such as gynecological,
orthopedic, and ontological procedures [
2
]. Additionally, DCF specializes in the treatment
of osteoarthritis, renal and biliary cramps, pharyngotonsillitis, otitis, annexites, and pri-
mary dysmenorrhea, as well as various infection-related pain operations [
1
–
3
]. According
to a study in 2018, around half of the original medication was metabolized; moreover,
70% of pharmaceuticals was excreted via urine, despite diverse conditions occurring in
relation to those targeted drugs [
4
]. The risk assessment of drug toxicity revealed that,
according to data on the DCF presence in wastewater following standard biological treat-
ment, around 80% of the original pollutant was retained [
5
]. Inefficient effluent treatment
plants that failed to eliminate drugs from wastewater were utilized to develop four drug
detection techniques.
Many methods have been employed for DCF detection, such as immunoassays, chro-
matographic techniques, and electrochemical methods [
6
–
8
]. Clearly, these techniques,
which provide the efficient detection of DCF at concentrations ranging from M to nM, are
not without limitations, including the requirement for costly equipment. Additionally, they
consume significantly more time and need complicated preprocessing, limiting their practi-
cal applicability [
9
,
10
]. As a result, a sensitive and selective sensor capable of providing
more promptness and ease for DCF detection needs to be built.
Photoelectrochemical (PEC) sensors, which specialize in high sensitivity, simply struc-
tured instruments, easily conducted downsizing, and low prices, have previously attracted
academics to conduct research on them [
11
–
13
]. When developing PEC sensors, improved
photocatalyst performance contributes to increased sensitivity. Nonetheless, PEC sensing
must rely on photocatalytic processes that lack analyte specificity. To overcome the issue,
significant efforts have been made to improve the selectivity of PEC sensors by including
Nanomaterials 2022, 12, 2834. https://doi.org/10.3390/nano12162834 https://www.mdpi.com/journal/nanomaterials
