Citation: Xu, S.; Xu, Z.; Liu, Z.
Paper-Based Molecular-Imprinting
Technology and Its Application.
Biosensors 2022, 12, 595.
https://doi.org/10.3390/
bios12080595
Received: 15 July 2022
Accepted: 2 August 2022
Published: 3 August 2022
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Perspective
Paper-Based Molecular-Imprinting Technology and Its
Application
Shufang Xu, Zhigang Xu * and Zhimin Liu *
Faculty of Science, Kunming University of Science and Technology, Kunming 650500, China;
xsf2634098266@163.com
* Correspondence: chemxuzg@kust.edu.cn (Z.X.); lab_chem@126.com (Z.L.)
Abstract:
Paper-based analytical devices (PADs) are highly effective tools due to their low cost,
portability, low reagent accumulation, and ease of use. Molecularly imprinted polymers (MIP) are
also extensively used as biomimetic receptors and specific adsorption materials for capturing target
analytes in various complex matrices due to their excellent recognition ability and structural stability.
The integration of MIP and PADs (MIP-PADs) realizes the rapid, convenient, and low-cost application
of molecular-imprinting analysis technology. This review introduces the characteristics of MIP-PAD
technology and discusses its application in the fields of on-site environmental analysis, food-safety
monitoring, point-of-care detection, biomarker detection, and exposure assessment. The problems
and future development of MIP-PAD technology in practical application are also prospected.
Keywords:
paper-based analytical devices; paper-based molecular-imprinting technology;
molecularly imprinted polymer
1. Introduction
Paper-based analytical devices (PADs) are an emerging class of platforms that can
operate without complex instrumentation, making them ideal for rapid analysis and
deployment in areas lacking medical resources. Compared with traditional analytical
techniques, paper-based devices have many advantages, such as low manufacturing cost,
ease of operation, rapid detection, and ease of handling after testing. As a versatile
substrate, paper has a porous structure that enables its surface to be easily modified
and thus acquire a large surface-to-volume ratio. This makes it an excellent support for
incorporating functional nanomaterials and a flexible platform for developing sophisticated
analytical devices. Since 2007 when Whitesides’ group [
1
] patterned paper to create
millimeter-scale channels, the applications of PADs have been reported in the fields of
point-of-care testing [
2
,
3
], environmental monitoring [
4
–
6
], food-safety assessment [
7
–
9
],
and biomedicine [
10
–
12
]. Currently, PADs are in paper chromatography [
13
,
14
], as lateral-
flow test paper [
15
,
16
], as paper-based microfluidic devices [
17
,
18
], and in paper-spray
ionization (PSI) [
19
,
20
], among others. However, despite the potential of PADs, their low
accuracy and poor anti-interference ability under complex detection conditions limit their
applications to a certain extent. Variations in the specificity of PADs in complex matrices
such as blood and urine can lead to false-positive or false-negative test results, which
reduce the accuracy and reliability of paper-based tests.
Molecularly imprinted polymers (MIPs) are a class of polymer-based biomimetic
receptors. MIPs first combine template molecules and functional monomers with covalent
or noncovalent bonds through self-assembly. Then they complete the polymerization in
the presence of cross-linking agents and initiators. Finally, the template molecules are
removed, thereby forming specific binding sites or cavities that are complementary in size
and shape to the template molecule [
21
]. MIP exhibits good stability and resistance to
matrix interference. Since 1931 when MIPs were first reported by Polyakov [
22
] using a
Biosensors 2022, 12, 595. https://doi.org/10.3390/bios12080595 https://www.mdpi.com/journal/biosensors
