Smart Materials for Chemical and Biosensing

A special issue of Biosensors (ISSN 2079-6374). This special issue belongs to the section "Biosensor Materials".

Deadline for manuscript submissions: closed (30 September 2023) | Viewed by 34218

Special Issue Editor

School of Instrumentation and Optoelectronic Engineering, Beihang University, Beijing 100191, China
Interests: photonic crystals; chemical and biosensors; optical sensors; smart materials; wearable devices
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Smart materials, also known as stimuli-responsive materials, can respond to external stimuili such as pH, temperature, humidity, electric or magnetic fields, stress, light, and chemical or biological stimuli via changing their shape, color, or size. Smart materials such as piezoceramics, shape-memory alloys, and dielectric elastomers have been widely developed in recent years for application in sensors and actuators, medicine, engineering, etc. In recent years, novel smart materials such as hydrogels, liquid crystals, nanomaterials (e.g., gold nanoparticles, quantum dots, carbon nanotubes, MOF, graphene), responsive polymers and biopolymers, shape memory metals, piezoelectric materials, and biomaterials have been widely used for applications in chemical and biosensing.

In this Special Issue, we would like to focus on smart materials for chemical and biosensing applications. We welcome the submission of original research or review articles on the chemical or biosensing applications of any types of smart materials.

Prof. Dr. Zhongyu Cai
Guest Editor

Manuscript Submission Information

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Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Biosensors is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • smart materials
  • intelligent materials
  • nanomaterials
  • biomaterials
  • hydrogels
  • organogels
  • responsive polymers
  • actuators
  • chemical sensors
  • biosensors
  • wearable devices
  • soft robotics

Published Papers (12 papers)

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Research

Jump to: Review

14 pages, 4293 KiB  
Article
Nanosphere Lithography-Enabled Hybrid Ag-Cu Surface-Enhanced Raman Spectroscopy Substrates with Enhanced Absorption of Excitation Light
by Zixuan Wu, Jianxun Liu, Zhenming Wang, Lei Chen, Yiwei Xu, Zongjun Ma, Delai Kong, Dan Luo and Yan Jun Liu
Biosensors 2023, 13(8), 825; https://doi.org/10.3390/bios13080825 - 17 Aug 2023
Viewed by 986
Abstract
We demonstrated a low-cost, highly sensitive hybrid Ag-Cu substrate with enhanced absorption for the excitation laser beam via the nanosphere lithography technique. The hybrid Ag-Cu surface-enhanced Raman spectroscopy (SERS) substrate consists of a Cu nanoarray covered with Ag nanoparticles. The geometry of the [...] Read more.
We demonstrated a low-cost, highly sensitive hybrid Ag-Cu substrate with enhanced absorption for the excitation laser beam via the nanosphere lithography technique. The hybrid Ag-Cu surface-enhanced Raman spectroscopy (SERS) substrate consists of a Cu nanoarray covered with Ag nanoparticles. The geometry of the deposited Cu nanoarray is precisely determined through a self-assembly nanosphere etching process, resulting in optimized absorption for the excitation laser beam. Further Raman enhancement is achieved by incorporating plasmonic hotspots formed by dense Ag nanoparticles, grown by immersing the prepared Cu nanoarray in a silver nitrate solution. The structural design enables analytical enhancement factor of hybrid Ag-Cu SERS substrates of 1.13 × 105. The Ag-Cu SERS substrates exhibit a highly sensitive and reproducible SERS activity, with a low detection limit of 10−13 M for Rhodamine 6G detection and 10−9 M for 4,4′-Bipyridine. Our strategy could pave an effective and promising approach for SERS-based rapid detection in biosensors, environmental monitoring and food safety. Full article
(This article belongs to the Special Issue Smart Materials for Chemical and Biosensing)
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20 pages, 2959 KiB  
Article
Obtaining of ZnO/Fe2O3 Thin Nanostructured Films by AACVD for Detection of ppb-Concentrations of NO2 as a Biomarker of Lung Infections
by Artem S. Mokrushin, Yulia M. Gorban, Aleksey A. Averin, Philipp Yu. Gorobtsov, Nikolay P. Simonenko, Yury Yu. Lebedinskii, Elizaveta P. Simonenko and Nikolay T. Kuznetsov
Biosensors 2023, 13(4), 445; https://doi.org/10.3390/bios13040445 - 31 Mar 2023
Cited by 4 | Viewed by 1994
Abstract
ZnO/Fe2O3 nanocomposites with different concentration and thickness of the Fe2O3 layer were obtained by two-stage aerosol vapor deposition (AACVD). It was shown that the ZnO particles have a wurtzite structure with an average size of 51–66 nm, [...] Read more.
ZnO/Fe2O3 nanocomposites with different concentration and thickness of the Fe2O3 layer were obtained by two-stage aerosol vapor deposition (AACVD). It was shown that the ZnO particles have a wurtzite structure with an average size of 51–66 nm, and the iron oxide particles on the ZnO surface have a hematite structure and an average size of 23–28 nm. According to EDX data, the iron content in the films was found to be 1.3–5.8 at.%. The optical properties of the obtained films were studied, and the optical band gap was found to be 3.16–3.26 eV. Gas-sensitive properties at 150–300 °C were studied using a wide group of analyte gases: CO, NH3, H2, CH4, C6H6, ethanol, acetone, and NO2. A high response to 100 ppm acetone and ethanol at 225–300 °C and a high and selective response to 300–2000 ppb NO2 at 175 °C were established. The effect of humidity on the magnitude and shape of the signal obtained upon NO2 detection was studied. Full article
(This article belongs to the Special Issue Smart Materials for Chemical and Biosensing)
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9 pages, 3098 KiB  
Communication
A Biomass Based Photonic Crystal Hydrogel Made of Bletilla striata Polysaccharide
by Bo Sun, Wenxin Zhang, Yangyang Liu, Min Xue, Lili Qiu and Zihui Meng
Biosensors 2022, 12(10), 841; https://doi.org/10.3390/bios12100841 - 08 Oct 2022
Cited by 2 | Viewed by 1622
Abstract
Bletilla striata is an herb with a good medicinal value whose main active ingredient is Bletilla striata polysaccharide (BSP) in the tuber of Bletilla striata. In this study, a polysaccharide-based semi-interpenetrating network hydrogel was constructed by introducing BSP into polyacrylamide (PAM) hydrogel. [...] Read more.
Bletilla striata is an herb with a good medicinal value whose main active ingredient is Bletilla striata polysaccharide (BSP) in the tuber of Bletilla striata. In this study, a polysaccharide-based semi-interpenetrating network hydrogel was constructed by introducing BSP into polyacrylamide (PAM) hydrogel. The introduction of the BSP chain no only maintains the excellent mechanical properties of PAM, but also endows it with good biocompatibility. By implanting the colloidal crystal array into the above hydrogels, we obtained a novel biomass-based photonic crystal with good stimulus responsiveness that is sensitive to volatile organic compounds (VOCs), especially alcohol vapor. In addition, due to the scavenging ability of BSP to hydroxyl radicals, the photonic crystal hydrogel also has a good response to hydrogen peroxide (H2O2). Full article
(This article belongs to the Special Issue Smart Materials for Chemical and Biosensing)
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15 pages, 4608 KiB  
Article
Multi-Factors Cooperatively Actuated Photonic Hydrogel Aptasensors for Facile, Label-Free and Colorimetric Detection of Lysozyme
by Peiyan Shen, Yuqing Shi, Ran Li, Bo Han, Haojie Ma, Xueyan Hou, Yuqi Zhang and Lei Jiang
Biosensors 2022, 12(8), 662; https://doi.org/10.3390/bios12080662 - 20 Aug 2022
Cited by 4 | Viewed by 1891
Abstract
Responsive two-dimensional photonic crystal (2DPC) hydrogels have been widely used as smart sensing materials for constructing various optical sensors to accurately detect different target analytes. Herein, we report photonic hydrogel aptasensors based on aptamer-functionalized 2DPC poly(acrylamide-acrylic acid-N-tert-butyl acrylamide) hydrogels for facile, label-free and [...] Read more.
Responsive two-dimensional photonic crystal (2DPC) hydrogels have been widely used as smart sensing materials for constructing various optical sensors to accurately detect different target analytes. Herein, we report photonic hydrogel aptasensors based on aptamer-functionalized 2DPC poly(acrylamide-acrylic acid-N-tert-butyl acrylamide) hydrogels for facile, label-free and colorimetric detection of lysozyme in human serum. The constructed photonic hydrogel aptasensors undergo shrinkage upon exposure to lysozyme solution through multi-factors cooperative actuation. Here, the specific binding between the aptamer and lysozyme, and the simultaneous interactions between carboxyl anions and N-tert-butyl groups with lysozyme, increase the cross-linking density of the hydrogel, leading to its shrinkage. The aptasensors’ shrinkage decreases the particle spacing of the 2DPC embedded in the hydrogel network. It can be simply monitored by measuring the Debye diffraction ring of the photonic hydrogel aptasensors using a laser pointer and a ruler without needing sophisticated apparatus. The significant shrinkage of the aptasensors can be observed by the naked eye via the hydrogel size and color change. The aptasensors show good sensitivity with a limit of detection of 1.8 nM, high selectivity and anti-interference for the detection of lysozyme. The photonic hydrogel aptasensors have been successfully used to accurately determine the concentration of lysozyme in human serum. Therefore, novel photonic hydrogel aptasensors can be constructed by designing functional monomers and aptamers that can specifically bind target analytes. Full article
(This article belongs to the Special Issue Smart Materials for Chemical and Biosensing)
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16 pages, 2227 KiB  
Article
A Redox-Probe-Free Immunosensor Based on Electrocatalytic Prussian Blue Nanostructured Film One-Step-Prepared for Zika Virus Diagnosis
by Lorenna K. B. Santos, Priscila D. Mendonça, LiLian K. S. Assis, Carlos R. Prudêncio, Maria Izabel F. Guedes, Ernesto T. A. Marques and Rosa Fireman Dutra
Biosensors 2022, 12(8), 623; https://doi.org/10.3390/bios12080623 - 10 Aug 2022
Cited by 4 | Viewed by 2391
Abstract
The Zika virus (ZIKV) is a great concern for global health due to its high transmission, including disseminating through blood, saliva, urine, semen and vertical transmission. In some cases, ZIKV has been associated with microcephaly, neurological disorders, and Guillain–Barré syndrome. There is no [...] Read more.
The Zika virus (ZIKV) is a great concern for global health due to its high transmission, including disseminating through blood, saliva, urine, semen and vertical transmission. In some cases, ZIKV has been associated with microcephaly, neurological disorders, and Guillain–Barré syndrome. There is no vaccine, and controlling the disease is a challenge, especially with the co-circulation of the Dengue virus, which causes a severe cross-reaction due to the similarity between the two arboviruses. Considering that electrochemical immunosensors are well-established, sensitive, and practical tools for diagnosis, in this study we developed a sensor platform with intrinsic redox activity that facilitates measurement readouts. Prussian blue (PB) has a great ability to form electrocatalytic surfaces, dispensing redox probe solutions in voltammetric measurements. Herein, PB was incorporated into a chitosan–carbon nanotube hybrid, forming a nanocomposite that was drop-casted on a screen-printed electrode (SPE). The immunosensor detected the envelope protein of ZIKV in a linear range of 0.25 to 1.75 µg/mL (n = 8, p < 0.01), with a 0.20 µg/mL limit of detection. The developed immunosensor represents a new method for electrochemical measurements without additional redox probe solutions, and it is feasible for application in point-of-care diagnosis. Full article
(This article belongs to the Special Issue Smart Materials for Chemical and Biosensing)
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11 pages, 3504 KiB  
Article
A Polypyrrole/Nanoclay Hybrid Film for Ultra-Sensitive Cardiac Troponin T Electrochemical Immunosensor
by Vicente P. A. Landim, Marcos V. Foguel, Cecília M. Prado, Maria P. T. Sotomayor, Iolanda C. Vieira, Bárbara V. M. Silva and Rosa F. Dutra
Biosensors 2022, 12(7), 545; https://doi.org/10.3390/bios12070545 - 21 Jul 2022
Cited by 5 | Viewed by 1824
Abstract
An electrochemical immunosensor based on a nanohybrid film of carboxylated polypyrrole and amine nanoclay was developed for label-free detection of the human cardiac troponin T (cTnT). The nanohybrid film was formed in situ on the surface of the glassy carbon electrode, followed by [...] Read more.
An electrochemical immunosensor based on a nanohybrid film of carboxylated polypyrrole and amine nanoclay was developed for label-free detection of the human cardiac troponin T (cTnT). The nanohybrid film was formed in situ on the surface of the glassy carbon electrode, followed by the covalent immobilization of anti-troponin T antibodies by glutaraldehyde. Morphological and chemical characterizations of the nanohybrid film were performed by scanning electron microscopy and Fourier-transform infrared spectroscopy. Under the optimized conditions, a calibration curve for cTnT in spiked serum was obtained by square wave voltammetry, and a low limit of detection and quantification was achieved (0.35 and 1.05 pg mL−1, respectively). This was the first time that this type of nanohybrid film was used in the development of an immunosensor for cTnT that proved to be a simple and efficient strategy for the manufacture of a label-free electrochemical device that could be applied in the diagnosis of acute myocardial infarction. Full article
(This article belongs to the Special Issue Smart Materials for Chemical and Biosensing)
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Review

Jump to: Research

20 pages, 4668 KiB  
Review
Recent Advances in Bitterness-Sensing Systems
by Yanqi Li, Nigel Langley and Jiantao Zhang
Biosensors 2023, 13(4), 414; https://doi.org/10.3390/bios13040414 - 23 Mar 2023
Viewed by 2921
Abstract
Bitterness is one of the basic tastes, and sensing bitterness plays a significant role in mammals recognizing toxic substances. The bitter taste of food and oral medicines may decrease consumer compliance. As a result, many efforts have been made to mask or decrease [...] Read more.
Bitterness is one of the basic tastes, and sensing bitterness plays a significant role in mammals recognizing toxic substances. The bitter taste of food and oral medicines may decrease consumer compliance. As a result, many efforts have been made to mask or decrease the bitterness in food and oral pharmaceutical products. The detection of bitterness is critical to evaluate how successful the taste-masking technology is, and many novel taste-sensing systems have been developed on the basis of various interaction mechanisms. In this review, we summarize the progress of bitterness response mechanisms and the development of novel sensors in detecting bitterness ranging from commercial electronic devices based on modified electrodes to micro-type sensors functionalized with taste cells, polymeric membranes, and other materials in the last two decades. The challenges and potential solutions to improve the taste sensor quality are also discussed. Full article
(This article belongs to the Special Issue Smart Materials for Chemical and Biosensing)
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29 pages, 5955 KiB  
Review
Review of HIV Self Testing Technologies and Promising Approaches for the Next Generation
by Amanda Bacon, Weijing Wang, Hankeun Lee, Saurabh Umrao, Prima Dewi Sinawang, Demir Akin, Kodchakorn Khemtonglang, Anqi Tan, Sabina Hirshfield, Utkan Demirci, Xing Wang and Brian T. Cunningham
Biosensors 2023, 13(2), 298; https://doi.org/10.3390/bios13020298 - 20 Feb 2023
Cited by 5 | Viewed by 7223
Abstract
The ability to self-test for HIV is vital to preventing transmission, particularly when used in concert with HIV biomedical prevention modalities, such as pre-exposure prophylaxis (PrEP). In this paper, we review recent developments in HIV self-testing and self-sampling methods, and the potential future [...] Read more.
The ability to self-test for HIV is vital to preventing transmission, particularly when used in concert with HIV biomedical prevention modalities, such as pre-exposure prophylaxis (PrEP). In this paper, we review recent developments in HIV self-testing and self-sampling methods, and the potential future impact of novel materials and methods that emerged through efforts to develop more effective point-of-care (POC) SARS-CoV-2 diagnostics. We address the gaps in existing HIV self-testing technologies, where improvements in test sensitivity, sample-to-answer time, simplicity, and cost are needed to enhance diagnostic accuracy and widespread accessibility. We discuss potential paths toward the next generation of HIV self-testing through sample collection materials, biosensing assay techniques, and miniaturized instrumentation. We discuss the implications for other applications, such as self-monitoring of HIV viral load and other infectious diseases. Full article
(This article belongs to the Special Issue Smart Materials for Chemical and Biosensing)
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28 pages, 5913 KiB  
Review
Smart Nanostructured Materials for SARS-CoV-2 and Variants Prevention, Biosensing and Vaccination
by Lifeng Wang and Zhiwei Li
Biosensors 2022, 12(12), 1129; https://doi.org/10.3390/bios12121129 - 05 Dec 2022
Viewed by 2140
Abstract
The coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has raised great concerns about human health globally. At the current stage, prevention and vaccination are still the most efficient ways to slow down the pandemic and [...] Read more.
The coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has raised great concerns about human health globally. At the current stage, prevention and vaccination are still the most efficient ways to slow down the pandemic and to treat SARS-CoV-2 in various aspects. In this review, we summarize current progress and research activities in developing smart nanostructured materials for COVID-19 prevention, sensing, and vaccination. A few established concepts to prevent the spreading of SARS-CoV-2 and the variants of concerns (VOCs) are firstly reviewed, which emphasizes the importance of smart nanostructures in cutting the virus spreading chains. In the second part, we focus our discussion on the development of stimuli-responsive nanostructures for high-performance biosensing and detection of SARS-CoV-2 and VOCs. The use of nanostructures in developing effective and reliable vaccines for SARS-CoV-2 and VOCs will be introduced in the following section. In the conclusion, we summarize the current research focus on smart nanostructured materials for SARS-CoV-2 treatment. Some existing challenges are also provided, which need continuous efforts in creating smart nanostructured materials for coronavirus biosensing, treatment, and vaccination. Full article
(This article belongs to the Special Issue Smart Materials for Chemical and Biosensing)
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19 pages, 33789 KiB  
Review
2D-Materials-Based Wearable Biosensor Systems
by Yi Wang, Tong Li, Yangfeng Li, Rong Yang and Guangyu Zhang
Biosensors 2022, 12(11), 936; https://doi.org/10.3390/bios12110936 - 27 Oct 2022
Cited by 10 | Viewed by 3284
Abstract
As an evolutionary success in life science, wearable biosensor systems, which can monitor human health information and quantify vital signs in real time, have been actively studied. Research in wearable biosensor systems is mainly focused on the design of sensors with various flexible [...] Read more.
As an evolutionary success in life science, wearable biosensor systems, which can monitor human health information and quantify vital signs in real time, have been actively studied. Research in wearable biosensor systems is mainly focused on the design of sensors with various flexible materials. Among them, 2D materials with excellent mechanical, optical, and electrical properties provide the expected characteristics to address the challenges of developing microminiaturized wearable biosensor systems. This review summarizes the recent research progresses in 2D-materials-based wearable biosensors including e-skin, contact lens sensors, and others. Then, we highlight the challenges of flexible power supply technologies for smart systems. The latest advances in biosensor systems involving wearable wristbands, diabetic patches, and smart contact lenses are also discussed. This review will enable a better understanding of the design principle of 2D biosensors, offering insights into innovative technologies for future biosensor systems toward their practical applications. Full article
(This article belongs to the Special Issue Smart Materials for Chemical and Biosensing)
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33 pages, 8402 KiB  
Review
Recent Advances in Nanomaterial-Based Biosensors for Pesticide Detection in Foods
by Ana Carolina de Morais Mirres, Brenno Enrique Pereira de Matos da Silva, Leticia Tessaro, Diego Galvan, Jelmir Craveiro de Andrade, Adriano Aquino, Nirav Joshi and Carlos Adam Conte-Junior
Biosensors 2022, 12(8), 572; https://doi.org/10.3390/bios12080572 - 27 Jul 2022
Cited by 11 | Viewed by 3430
Abstract
Biosensors are a simple, low-cost, and reliable way to detect pesticides in food matrices to ensure consumer food safety. This systematic review lists which nanomaterials, biorecognition materials, transduction methods, pesticides, and foods have recently been studied with biosensors associated with analytical performance. A [...] Read more.
Biosensors are a simple, low-cost, and reliable way to detect pesticides in food matrices to ensure consumer food safety. This systematic review lists which nanomaterials, biorecognition materials, transduction methods, pesticides, and foods have recently been studied with biosensors associated with analytical performance. A systematic search was performed in the Scopus (n = 388), Web of Science (n = 790), and Science Direct (n = 181) databases over the period 2016–2021. After checking the eligibility criteria, 57 articles were considered in this study. The most common use of nanomaterials (NMs) in these selected studies is noble metals in isolation, such as gold and silver, with 8.47% and 6.68%, respectively, followed by carbon-based NMs, with 20.34%, and nanohybrids, with 47.45%, which combine two or more NMs, uniting unique properties of each material involved, especially the noble metals. Regarding the types of transducers, the most used were electrochemical, fluorescent, and colorimetric, representing 71.18%, 13.55%, and 8.47%, respectively. The sensitivity of the biosensor is directly connected to the choice of NM and transducer. All biosensors developed in the selected investigations had a limit of detection (LODs) lower than the Codex Alimentarius maximum residue limit and were efficient in detecting pesticides in food. The pesticides malathion, chlorpyrifos, and paraoxon have received the greatest attention for their effects on various food matrices, primarily fruits, vegetables, and their derivatives. Finally, we discuss studies that used biosensor detection systems devices and those that could detect multi-residues in the field as a low-cost and rapid technique, particularly in areas with limited resources. Full article
(This article belongs to the Special Issue Smart Materials for Chemical and Biosensing)
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29 pages, 2608 KiB  
Review
Colorimetric Systems for the Detection of Bacterial Contamination: Strategy and Applications
by Dong-Min Kim and Seung-Min Yoo
Biosensors 2022, 12(7), 532; https://doi.org/10.3390/bios12070532 - 16 Jul 2022
Cited by 12 | Viewed by 3549
Abstract
Bacterial contamination is a public health concern worldwide causing enormous social and economic losses. For early diagnosis and adequate management to prevent or treat pathogen-related illnesses, extensive effort has been put into the development of pathogenic bacterial detection systems. Colorimetric sensing systems have [...] Read more.
Bacterial contamination is a public health concern worldwide causing enormous social and economic losses. For early diagnosis and adequate management to prevent or treat pathogen-related illnesses, extensive effort has been put into the development of pathogenic bacterial detection systems. Colorimetric sensing systems have attracted increasing attention due to their simple and single-site operation, rapid signal readout with the naked eye, ability to operate without external instruments, portability, compact design, and low cost. In this article, recent trends and advances in colorimetric systems for the detection and monitoring of bacterial contamination are reviewed. This article focuses on pathogen detection strategies and technologies based on reaction factors that affect the color change for visual readout. Reactions used in each strategy are introduced by dividing them into the following five categories: external pH change-induced pH indicator reactions, intracellular enzyme-catalyzed chromogenic reactions, enzyme-like nanoparticle (NP)-catalyzed substrate reactions, NP aggregation-based reactions, and NP accumulation-based reactions. Some recently developed colorimetric systems are introduced, and their challenges and strategies to improve the sensing performance are discussed. Full article
(This article belongs to the Special Issue Smart Materials for Chemical and Biosensing)
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