1
|
Wang S, Zhou Z, Cao M, Pan Y, Zhang Y, Fang Y, Sun Q, Lei X, Le T. A comprehensive review of aptamer screening and application for lateral flow strip: Current status and future perspectives. Talanta 2024; 275:126181. [PMID: 38692047 DOI: 10.1016/j.talanta.2024.126181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 04/16/2024] [Accepted: 04/27/2024] [Indexed: 05/03/2024]
Abstract
The detection of biomarkers is of great significance for medical diagnosis, food safety, environmental monitoring, and agriculture. However, bio-detection technology at present often necessitates complex instruments, expensive reagents, specialized expertise, and prolonged procedures, making it challenging to fulfill the demand for rapid, sensitive, user-friendly, and economical testing. In contrast, lateral flow strip (LFS) technology offers simple, fast, and visually accessible detection modality, allowing real-time analysis of clinical specimens, thus finding widespread utility across various domains. Within the realm of LFS, the application of aptamers as molecular recognition probes presents distinct advantages over antibodies, including cost-effectiveness, smaller size, ease of synthesis, and chemical stability. In recent years, aptamer-based LFS has found extensive application in qualitative, semi-quantitative, and quantitative detection across food safety, environmental surveillance, clinical diagnostics, and other domains. This review provided a concise overview of different aptamer screening methodologies, selection strategies, underlying principles, and procedural, elucidating their respective advantages, limitations, and applications. Additionally, we summarized recent strategies and mechanisms for aptamer-based LFS, such as the sandwich and competitive methods. Furthermore, we classified LFSs constructed based on aptamers, considering the rapid advancements in this area, and discussed their applications in biological and chemical detection. Finally, we delved into the current challenges and future directions in the development of aptamer and aptamer-based LFS. Although this review was not thoroughly, it would serve as a valuable reference for understanding the research progress of aptamer-based LFS and aid in the development of new types of aptasensors.
Collapse
Affiliation(s)
- Sixian Wang
- College of Life Sciences, Chongqing Collaborative Innovation Center for Rapid Detection of Food Quality and Safety, Chongqing Key Laboratory of Conservation and Utilization of Freshwater Fishes, Chongqing Normal University, Chongqing, 401331, China.
| | - Zhaoyang Zhou
- College of Life Sciences, Chongqing Collaborative Innovation Center for Rapid Detection of Food Quality and Safety, Chongqing Key Laboratory of Conservation and Utilization of Freshwater Fishes, Chongqing Normal University, Chongqing, 401331, China
| | - Mingdong Cao
- College of Life Sciences, Chongqing Collaborative Innovation Center for Rapid Detection of Food Quality and Safety, Chongqing Key Laboratory of Conservation and Utilization of Freshwater Fishes, Chongqing Normal University, Chongqing, 401331, China
| | - Yangwei Pan
- College of Life Sciences, Chongqing Collaborative Innovation Center for Rapid Detection of Food Quality and Safety, Chongqing Key Laboratory of Conservation and Utilization of Freshwater Fishes, Chongqing Normal University, Chongqing, 401331, China
| | - Yongkang Zhang
- College of Life Sciences, Chongqing Collaborative Innovation Center for Rapid Detection of Food Quality and Safety, Chongqing Key Laboratory of Conservation and Utilization of Freshwater Fishes, Chongqing Normal University, Chongqing, 401331, China
| | - Yu Fang
- College of Life Sciences, Chongqing Collaborative Innovation Center for Rapid Detection of Food Quality and Safety, Chongqing Key Laboratory of Conservation and Utilization of Freshwater Fishes, Chongqing Normal University, Chongqing, 401331, China
| | - Qi Sun
- College of Life Sciences, Chongqing Collaborative Innovation Center for Rapid Detection of Food Quality and Safety, Chongqing Key Laboratory of Conservation and Utilization of Freshwater Fishes, Chongqing Normal University, Chongqing, 401331, China
| | - Xianlu Lei
- College of Life Sciences, Chongqing Collaborative Innovation Center for Rapid Detection of Food Quality and Safety, Chongqing Key Laboratory of Conservation and Utilization of Freshwater Fishes, Chongqing Normal University, Chongqing, 401331, China
| | - Tao Le
- College of Life Sciences, Chongqing Collaborative Innovation Center for Rapid Detection of Food Quality and Safety, Chongqing Key Laboratory of Conservation and Utilization of Freshwater Fishes, Chongqing Normal University, Chongqing, 401331, China.
| |
Collapse
|
2
|
Zhan K, Chen L, Li S, Yu Q, Zhao Z, Li J, Xing Y, Ren H, Wang N, Zhang G. A novel metal-organic framework based electrochemical immunosensor for the rapid detection of Salmonella typhimurium detection in milk. Food Chem 2024; 444:138672. [PMID: 38330614 DOI: 10.1016/j.foodchem.2024.138672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 01/15/2024] [Accepted: 02/02/2024] [Indexed: 02/10/2024]
Abstract
Salmonella is one of the most prevalent pathogens causing foodborne diseases. In this study, a novel electrochemical immunosensor was designed for the rapid and accurate detection of Salmonella typhimurium (S. typhimurium) in milk. Platinum nanoparticles and Co/Zn-metal-organic framework @carboxylic multiwalled carbon nanotubes in the immunosensor acted synergistically to enhance the sensing sensitivity and stability. The materials and sensors were characterised using X-ray diffractometry, scanning electron microscopy, Fourier-transform infrared spectroscopy, differential pulse voltammetry, cyclic voltammetry, and other techniques. The optimised immunosensor showed a linear response for S. typhimurium concentrations in the range from 1.3 × 102 to 1.3 × 108 CFU mL-1, with a detection limit of 9.4 × 101 CFU mL-1. The assay also demonstrates good specificity, reproducibility, stability, and practical application potential, and the method can be extended to other foodborne pathogens.
Collapse
Affiliation(s)
- Ke Zhan
- College of Food Science and Technology, Henan Agricultural University, Zhengzhou 450002, Henan, China; College of Veterinary Medicine International Joint Research Center for Animal Immunology, Zhengzhou 450046, Henan, China; Longhu Laboratory of Advanced Immunology, Zhengzhou 450046, China; Key Laboratory of Animal Immunology of the Ministry of Agriculture, Henan Academy of Agricultural Sciences, 450002 Henan, China; Key Laboratory of Nutrition and Healthy Food of Zhengzhou, Zhengzhou 450002, Henan, China
| | - Linlin Chen
- College of Food Science and Technology, Henan Agricultural University, Zhengzhou 450002, Henan, China; College of Veterinary Medicine International Joint Research Center for Animal Immunology, Zhengzhou 450046, Henan, China; Longhu Laboratory of Advanced Immunology, Zhengzhou 450046, China; Key Laboratory of Animal Immunology of the Ministry of Agriculture, Henan Academy of Agricultural Sciences, 450002 Henan, China; Key Laboratory of Nutrition and Healthy Food of Zhengzhou, Zhengzhou 450002, Henan, China
| | - Shanshan Li
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450002, Henan, China; College of Veterinary Medicine International Joint Research Center for Animal Immunology, Zhengzhou 450046, Henan, China; Longhu Laboratory of Advanced Immunology, Zhengzhou 450046, China; Key Laboratory of Animal Immunology of the Ministry of Agriculture, Henan Academy of Agricultural Sciences, 450002 Henan, China; Key Laboratory of Nutrition and Healthy Food of Zhengzhou, Zhengzhou 450002, Henan, China
| | - Qiuying Yu
- College of Food Science and Technology, Henan Agricultural University, Zhengzhou 450002, Henan, China; College of Veterinary Medicine International Joint Research Center for Animal Immunology, Zhengzhou 450046, Henan, China; Longhu Laboratory of Advanced Immunology, Zhengzhou 450046, China; Key Laboratory of Animal Immunology of the Ministry of Agriculture, Henan Academy of Agricultural Sciences, 450002 Henan, China; Key Laboratory of Nutrition and Healthy Food of Zhengzhou, Zhengzhou 450002, Henan, China
| | - Zheng Zhao
- College of Food Science and Technology, Henan Agricultural University, Zhengzhou 450002, Henan, China; College of Veterinary Medicine International Joint Research Center for Animal Immunology, Zhengzhou 450046, Henan, China; Longhu Laboratory of Advanced Immunology, Zhengzhou 450046, China; Key Laboratory of Animal Immunology of the Ministry of Agriculture, Henan Academy of Agricultural Sciences, 450002 Henan, China; Key Laboratory of Nutrition and Healthy Food of Zhengzhou, Zhengzhou 450002, Henan, China
| | - Junwei Li
- College of Food Science and Technology, Henan Agricultural University, Zhengzhou 450002, Henan, China; College of Veterinary Medicine International Joint Research Center for Animal Immunology, Zhengzhou 450046, Henan, China; Longhu Laboratory of Advanced Immunology, Zhengzhou 450046, China; Key Laboratory of Animal Immunology of the Ministry of Agriculture, Henan Academy of Agricultural Sciences, 450002 Henan, China; Key Laboratory of Nutrition and Healthy Food of Zhengzhou, Zhengzhou 450002, Henan, China
| | - Yunrui Xing
- Key Laboratory of Animal Immunology of the Ministry of Agriculture, Henan Academy of Agricultural Sciences, 450002 Henan, China
| | - Hongtao Ren
- College of Food Science and Technology, Henan Agricultural University, Zhengzhou 450002, Henan, China; College of Veterinary Medicine International Joint Research Center for Animal Immunology, Zhengzhou 450046, Henan, China; Longhu Laboratory of Advanced Immunology, Zhengzhou 450046, China; Key Laboratory of Animal Immunology of the Ministry of Agriculture, Henan Academy of Agricultural Sciences, 450002 Henan, China; Key Laboratory of Nutrition and Healthy Food of Zhengzhou, Zhengzhou 450002, Henan, China.
| | - Na Wang
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450002, Henan, China; College of Veterinary Medicine International Joint Research Center for Animal Immunology, Zhengzhou 450046, Henan, China; Longhu Laboratory of Advanced Immunology, Zhengzhou 450046, China; Key Laboratory of Animal Immunology of the Ministry of Agriculture, Henan Academy of Agricultural Sciences, 450002 Henan, China; Key Laboratory of Nutrition and Healthy Food of Zhengzhou, Zhengzhou 450002, Henan, China.
| | - Gaiping Zhang
- College of Veterinary Medicine International Joint Research Center for Animal Immunology, Zhengzhou 450046, Henan, China; Longhu Laboratory of Advanced Immunology, Zhengzhou 450046, China; School of Advanced Agriculture Sciences, Peking University, 100871 Beijing, China; Key Laboratory of Animal Immunology of the Ministry of Agriculture, Henan Academy of Agricultural Sciences, 450002 Henan, China
| |
Collapse
|
3
|
Zhao X, Bhat A, O’Connor C, Curtin J, Singh B, Tian F. Review of Detection Limits for Various Techniques for Bacterial Detection in Food Samples. NANOMATERIALS (BASEL, SWITZERLAND) 2024; 14:855. [PMID: 38786811 PMCID: PMC11124167 DOI: 10.3390/nano14100855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Revised: 05/07/2024] [Accepted: 05/12/2024] [Indexed: 05/25/2024]
Abstract
Foodborne illnesses can be infectious and dangerous, and most of them are caused by bacteria. Some common food-related bacteria species exist widely in nature and pose a serious threat to both humans and animals; they can cause poisoning, diseases, disabilities and even death. Rapid, reliable and cost-effective methods for bacterial detection are of paramount importance in food safety and environmental monitoring. Polymerase chain reaction (PCR), lateral flow immunochromatographic assay (LFIA) and electrochemical methods have been widely used in food safety and environmental monitoring. In this paper, the recent developments (2013-2023) covering PCR, LFIA and electrochemical methods for various bacterial species (Salmonella, Listeria, Campylobacter, Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli)), considering different food sample types, analytical performances and the reported limit of detection (LOD), are discussed. It was found that the bacteria species and food sample type contributed significantly to the analytical performance and LOD. Detection via LFIA has a higher average LOD (24 CFU/mL) than detection via electrochemical methods (12 CFU/mL) and PCR (6 CFU/mL). Salmonella and E. coli in the Pseudomonadota domain usually have low LODs. LODs are usually lower for detection in fish and eggs. Gold and iron nanoparticles were the most studied in the reported articles for LFIA, and average LODs were 26 CFU/mL and 12 CFU/mL, respectively. The electrochemical method revealed that the average LOD was highest for cyclic voltammetry (CV) at 18 CFU/mL, followed by electrochemical impedance spectroscopy (EIS) at 12 CFU/mL and differential pulse voltammetry (DPV) at 8 CFU/mL. LOD usually decreases when the sample number increases until it remains unchanged. Exponential relations (R2 > 0.95) between LODs of Listeria in milk via LFIA and via the electrochemical method with sample numbers have been obtained. Finally, the review discusses challenges and future perspectives (including the role of nanomaterials/advanced materials) to improve analytical performance for bacterial detection.
Collapse
Affiliation(s)
- Xinyi Zhao
- School of Food Science and Environmental Health, Technological University Dublin, Grangegorman, D07 ADY7 Dublin, Ireland; (X.Z.); (A.B.); (C.O.); (B.S.)
- FOCAS Research Institute, Technological University Dublin, Camden Row, D08 CKP1 Dublin, Ireland
| | - Abhijnan Bhat
- School of Food Science and Environmental Health, Technological University Dublin, Grangegorman, D07 ADY7 Dublin, Ireland; (X.Z.); (A.B.); (C.O.); (B.S.)
- MiCRA Biodiagnostics Technology Gateway and Health, Engineering & Materials Sciences (HEMS) Research Hub, Technological University Dublin, D24 FKT9 Dublin, Ireland
| | - Christine O’Connor
- School of Food Science and Environmental Health, Technological University Dublin, Grangegorman, D07 ADY7 Dublin, Ireland; (X.Z.); (A.B.); (C.O.); (B.S.)
| | - James Curtin
- Faculty of Engineering and Built Environment, Technological University Dublin, Bolton Street, D01 K822 Dublin, Ireland;
| | - Baljit Singh
- School of Food Science and Environmental Health, Technological University Dublin, Grangegorman, D07 ADY7 Dublin, Ireland; (X.Z.); (A.B.); (C.O.); (B.S.)
- MiCRA Biodiagnostics Technology Gateway and Health, Engineering & Materials Sciences (HEMS) Research Hub, Technological University Dublin, D24 FKT9 Dublin, Ireland
| | - Furong Tian
- School of Food Science and Environmental Health, Technological University Dublin, Grangegorman, D07 ADY7 Dublin, Ireland; (X.Z.); (A.B.); (C.O.); (B.S.)
- FOCAS Research Institute, Technological University Dublin, Camden Row, D08 CKP1 Dublin, Ireland
| |
Collapse
|
4
|
Wang J, Shi L, Zhu X, Tang Q, Wu M, Li B, Liu W, Jin Y. Entropy-driven catalysis-based lateral flow assay for sensitive detection of Alzheimer 's-associated MicroRNA. Talanta 2024; 271:125656. [PMID: 38224658 DOI: 10.1016/j.talanta.2024.125656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Revised: 11/17/2023] [Accepted: 01/08/2024] [Indexed: 01/17/2024]
Abstract
Alzheimer's disease (AD) is a degenerative disease of the brain worldwide. Currently, there is no effective cure. But accurate and early diagnosis of AD is critical to the development of patient care and future treatments. MiRNA-16 has been considered as an effective diagnostic biomarker for AD because of its regulatory effect on key proteins of AD. Herein, a colorimetric lateral flow assay (LFA) was developed for sensitive detection of miRNA-16 based on entropy-driven catalysis (EDC) amplification strategy. MiRNA-16 triggered EDC and released more linker DNAs (LDNA) of sandwich structure. Thus, AuNPs were enriched at the T-line to enhance the colorimetric signal and improve the sensitivity of visual assay. It showed good specificity and sensitivity for detecting miRNA-16 with a detection limit of 1.01 pM. The practical detection of miRNA-16 in human serum obtained satisfactory result. Significantly, EDC achieved signal amplification in homogeneous solution without enzyme and DNA labeling, leading to a cheap and easy detection of miRNA-16. Therefore, it provided a portable and rapid assay for AD-related nucleic acid, which holds a potential for point-of-care testing (POCT) of AD.
Collapse
Affiliation(s)
- Jing Wang
- Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, 710119, China.
| | - Lu Shi
- Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, 710119, China
| | - Xinyu Zhu
- Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, 710119, China
| | - Qiaorong Tang
- Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, 710119, China
| | - Mengmeng Wu
- Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, 710119, China
| | - Baoxin Li
- Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, 710119, China
| | - Wei Liu
- Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, 710119, China
| | - Yan Jin
- Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, 710119, China.
| |
Collapse
|
5
|
Yu Q, Wu T, Tian B, Li J, Liu Y, Wu Z, Jin X, Wang C, Wang C, Gu B. Recent advances in SERS-based immunochromatographic assay for pathogenic microorganism diagnosis: A review. Anal Chim Acta 2024; 1286:341931. [PMID: 38049231 DOI: 10.1016/j.aca.2023.341931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 10/02/2023] [Accepted: 10/17/2023] [Indexed: 12/06/2023]
Abstract
Infectious diseases caused by bacteria, viruses, fungi, and other pathogenic microorganisms are among the most harmful public health problems in the world, causing tens of millions of deaths and incalculable economic losses every year. The establishment of rapid, simple, and highly sensitive diagnostic methods for pathogenic microorganisms is important for the prevention and control of infectious diseases, guidance of timely treatment, and the reduction of public safety risks. Lateral flow immunoassay (LFA) based on the colorimetric signal of colloidal gold is the most popular point-of-care testing technology at present, but it is limited by poor sensitivity and low throughput and hardly meets the needs of the highly sensitive screening of pathogenic microorganisms. In recent years, the combination of surface-enhanced Raman scattering (SERS) and LFA technology has developed into a novel analytical platform with high sensitivity and multiple detection capabilities and has shown great advantages in the detection of pathogenic microorganisms and infectious diseases. This review summarizes the working principle, design ideas, and application of the existing SERS-based LFA methods in pathogenic microorganism detection and further introduces the effect of new technologies such as Raman signal encoding, magnetic enrichment, novel membrane nanotags, and integrated Raman reading equipment on the performance of SERS-LFA. Finally, the main challenges and the future direction of development in this field of SERS-LFA are discussed.
Collapse
Affiliation(s)
- Qing Yu
- Department of Clinical Laboratory Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong, 510000, China; College of Life Sciences, Anhui Agricultural University, Hefei, 230036, China
| | - Ting Wu
- Department of Clinical Laboratory Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong, 510000, China
| | - Benshun Tian
- Department of Clinical Laboratory Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong, 510000, China
| | - Jiaxuan Li
- Department of Clinical Laboratory Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong, 510000, China
| | - Yun Liu
- Department of Clinical Laboratory Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong, 510000, China
| | - Zelan Wu
- Guangzhou Labway Clinical Laboratory Co., Ltd, Guangdong, 510000, China
| | - Xiong Jin
- Guangzhou Labway Clinical Laboratory Co., Ltd, Guangdong, 510000, China
| | - Chaoguang Wang
- College of Intelligence Science and Technology, National University of Defense Technology, Changsha, 410073, China.
| | - Chongwen Wang
- Department of Clinical Laboratory Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong, 510000, China; College of Life Sciences, Anhui Agricultural University, Hefei, 230036, China.
| | - Bing Gu
- Department of Clinical Laboratory Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong, 510000, China.
| |
Collapse
|
6
|
Zhong Y, Wu J, Pan X, Liu B, Wang L. Aptamer-functionalized polydiacetylene biosensor for the detection of three foodborne pathogens. ANAL SCI 2024; 40:199-211. [PMID: 37856010 DOI: 10.1007/s44211-023-00445-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Accepted: 09/27/2023] [Indexed: 10/20/2023]
Abstract
Rapid, simple and sensitive screening of foodborne pathogens is of great significance to ensure food safety. In this study, an aptamer-functionalized polydiacetylene (Apta-PDA) biosensor was developed for the detection of E. coli O157:H7, S. typhimurium or V. parahaemolyticus. First, aptamers responding to the target bacteria were modified on the surface of magnetic beads by covalent binding to form MBs-oligonucleotide conjugates for bacterial enrichment. Then, an Apta-PDA biosensor was obtained by connecting the aptamers to the PDA nanovesicles using the carbodiimide method. Molecular recognition occurred in the presence of the target bacteria, whereby the aptamer folded into a sequence-defined unique structure, resulting in an MBs-Apta/bacteria/Apta-PDA sandwich structure. Due to the optical properties of PDA, the blue-red transition of the detection system could be observed by the naked eye and quantified by the colorimetric response percentage (CR%). Under optimized conditions, the detection limits of E. coli O157:H7, S. typhimurium and V. parahaemolyticus were 39, 60 and 60 CFU/ml, respectively, with a selectivity of 100% and a reaction time of 30 min. Compared with the gold standard method, the accuracy of the three target bacteria detection reached 98%, 97.5% and 97%, respectively, and the sensitivity and specificity were both greater than 90%. The entire detection process was rapid and easy to execute without any special equipment, making this technology particularly suitable for resource-poor laboratories or regions.
Collapse
Affiliation(s)
- Yuhong Zhong
- Department of Clinical Laboratory, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, People's Republic of China.
| | - Jiaqi Wu
- School of Laboratory Medicine and Bioengineering, Hangzhou Medical College, Hangzhou, 310059, People's Republic of China
| | - Xiaoyan Pan
- Department of Clinical Laboratory, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, People's Republic of China
| | - Bo Liu
- Department of Clinical Laboratory, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, People's Republic of China
| | - Lin Wang
- Department of Clinical Laboratory, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, People's Republic of China
| |
Collapse
|
7
|
Diep Trinh TN, Trinh KTL, Lee NY. Microfluidic advances in food safety control. Food Res Int 2024; 176:113799. [PMID: 38163712 DOI: 10.1016/j.foodres.2023.113799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 11/23/2023] [Accepted: 12/02/2023] [Indexed: 01/03/2024]
Abstract
Food contamination is a global concern, particularly in developing countries. Two main types of food contaminants-chemical and biological-are common problems that threaten human health. Therefore, rapid and accurate detection methods are required to address the threat of food contamination. Conventional methods employed to detect these two types of food contaminants have several limitations, including high costs and long analysis time. Alternatively, microfluidic technology, which allows for simple, rapid, and on-site testing, can enable us to control food safety in a timely, cost-effective, simple, and accurate manner. This review summarizes advances in microfluidic approaches to detect contaminants in food. Different detection methods have been applied to microfluidic platforms to identify two main types of contaminants: chemical and biological. For chemical contaminant control, the application of microfluidic approaches for detecting heavy metals, pesticides, antibiotic residues, and other contaminants in food samples is reviewed. Different methods including enzymatic, chemical-based, immunoassay-based, molecular-based, and electrochemical methods for chemical contaminant detection are discussed based on their working principle, the integration in microfluidic platforms, advantages, and limitations. Microfluidic approaches for foodborne pathogen detection, from sample preparation to final detection, are reviewed to identify foodborne pathogens. Common methods for foodborne pathogens screening, namely immunoassay, nucleic acid amplification methods, and other methods are listed and discussed; highlighted examples of recent studies are also reviewed. Challenges and future trends that could be employed in microfluidic design and fabrication process to address the existing limitations for food safety control are also covered. Microfluidic technology is a promising tool for food safety control with high efficiency and applicability. Miniaturization, portability, low cost, and samples and reagents saving make microfluidic devices an ideal choice for on-site detection, especially in low-resource areas. Despite many advantages of microfluidic technology, the wide manufacturing of microfluidic devices still demands intensive studies to be conducted for user-friendly and accurate food safety control. Introduction of recent advances of microfluidic devices will build a comprehensive understanding of the technology and offer comparative analysis for future studies and on-site application.
Collapse
Affiliation(s)
- Thi Ngoc Diep Trinh
- Department of Materials Science, School of Applied Chemistry, Tra Vinh University, Viet Nam
| | - Kieu The Loan Trinh
- BioNano Applications Research Center, Gachon University, 1342 Seongnam-daero, Sujeong-gu, Seongnam-si, Gyeonggi-do 13120, Republic of Korea
| | - Nae Yoon Lee
- Department of BioNano Technology, Gachon University, 1342 Seongnam-daero, Sujeong-gu, Seongnam-si, Gyeonggi-do 13120, Republic of Korea.
| |
Collapse
|
8
|
Silva GBL, Campos FV, Guimarães MCC, Oliveira JP. Recent Developments in Lateral Flow Assays for Salmonella Detection in Food Products: A Review. Pathogens 2023; 12:1441. [PMID: 38133324 PMCID: PMC10747123 DOI: 10.3390/pathogens12121441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 11/22/2023] [Accepted: 12/11/2023] [Indexed: 12/23/2023] Open
Abstract
Salmonellosis is a disease transmitted by contaminated food and is one of the leading causes of infections worldwide, making the early detection of Salmonella of crucial importance for public health. However, current detection methods are laborious and time-consuming, thus impacting the entire food supply chain and leading to production losses and economic sanctions. To mitigate these issues, a number of different biosensors have been developed, including lateral flow assays (LFAs), which have emerged as valuable tools in pathogen detection due to their portability, ease of use, time efficiency, and cost effectiveness. The performance of LFAs has been considerably enhanced by the development of new nanomaterials over the years. In this review, we address the principles and formats of the assay and discuss future prospects and challenges with an emphasis on LFAs developed for the detection of different Salmonella serovars in food.
Collapse
Affiliation(s)
| | | | | | - Jairo P. Oliveira
- Morphology Department, Health Sciences Center, Federal University of Espírito Santo, Av Marechal Campos 1468, Vitória 29040-090, Brazil; (G.B.L.S.); (F.V.C.); (M.C.C.G.)
| |
Collapse
|
9
|
Dey MK, Iftesum M, Devireddy R, Gartia MR. New technologies and reagents in lateral flow assay (LFA) designs for enhancing accuracy and sensitivity. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2023; 15:4351-4376. [PMID: 37615701 DOI: 10.1039/d3ay00844d] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
Abstract
Lateral flow assays (LFAs) are a popular method for quick and affordable diagnostic testing because they are easy to use, portable, and user-friendly. However, LFA design has always faced challenges regarding sensitivity, accuracy, and complexity of the operation. By integrating new technologies and reagents, the sensitivity and accuracy of LFAs can be improved while minimizing the complexity and potential for false positives. Surface enhanced Raman spectroscopy (SERS), photoacoustic techniques, fluorescence resonance energy transfer (FRET), and the integration of smartphones and thermal readers can improve LFA accuracy and sensitivity. To ensure reliable and accurate results, careful assay design and validation, appropriate controls, and optimization of assay conditions are necessary. Continued innovation in LFA technology is crucial to improving the reliability and accuracy of rapid diagnostic testing and expanding its applications to various areas, such as food testing, water quality monitoring, and environmental testing.
Collapse
Affiliation(s)
- Mohan Kumar Dey
- Department of Mechanical and Industrial Engineering, Louisiana State University, Baton Rouge, LA 70803, USA.
| | - Maria Iftesum
- Department of Mechanical and Industrial Engineering, Louisiana State University, Baton Rouge, LA 70803, USA.
| | - Ram Devireddy
- Department of Mechanical and Industrial Engineering, Louisiana State University, Baton Rouge, LA 70803, USA.
| | - Manas Ranjan Gartia
- Department of Mechanical and Industrial Engineering, Louisiana State University, Baton Rouge, LA 70803, USA.
| |
Collapse
|
10
|
Liu X, Kukkar D, Deng Z, Yang D, Wang J, Kim KH, Zhang D. "Lock-and-key" recognizer-encoded lateral flow assays toward foodborne pathogen detection: An overview of their fundamentals and recent advances. Biosens Bioelectron 2023; 235:115317. [PMID: 37236010 DOI: 10.1016/j.bios.2023.115317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 04/11/2023] [Indexed: 05/28/2023]
Abstract
In light of severe health risks of foodborne pathogenic bacterial diseases, the potential utility of point-of-care (POC) sensors is recognized for pathogens detection. In this regard, lateral flow assay (LFA) is a promising and user-friendly option for such application among various technological approaches. This article presents a comprehensive review of "lock-and-key" recognizer-encoded LFAs with respect to their working principles and detection performance against foodborne pathogenic bacteria. For this purpose, we describe various strategies for bacteria recognition including the antibody-based antigen-antibody interactions, nucleic acid aptamer-based recognition, and phage-mediated targeting of bacterial cells. In addition, we also outline the technological challenges along with the prospects for the future development of LFA in food analysis. The LFA devices built based upon many recognition strategies are found to have great potential for rapid, convenient, and effective POC detection of pathogens in complex food matrixes. Future developments in this field should emphasize the development of high-quality bio-probes, multiplex sensors, and intelligent portable readers.
Collapse
Affiliation(s)
- Xiaojing Liu
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Deepak Kukkar
- Department of Biotechnology, Chandigarh University, Gharuan, Mohali, 147013, Punjab, India; University Centre for Research and Development, Chandigarh University, Gharuan, Mohali, 147013, Punjab, India
| | - Ziai Deng
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Di Yang
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Jianlong Wang
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Ki-Hyun Kim
- Department of Civil and Environmental Engineering, Hanyang University, Seongdong-gu, Wangsimni-ro, Seoul, 04763, South Korea.
| | - Daohong Zhang
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, Shaanxi, China.
| |
Collapse
|
11
|
Mao X, Ye R. One-Pot Synthesis of Enzyme and Antibody/CaHPO 4 Nanoflowers for Magnetic Chemiluminescence Immunoassay of Salmonella enteritidis. SENSORS (BASEL, SWITZERLAND) 2023; 23:2779. [PMID: 36904982 PMCID: PMC10006971 DOI: 10.3390/s23052779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 02/24/2023] [Accepted: 02/27/2023] [Indexed: 06/18/2023]
Abstract
In this study, through a bioinspired strategy, the horseradish peroxidase (HRP) and antibody (Ab) were co-embedded into CaHPO4 to prepare HRP-Ab-CaHPO4 (HAC) bifunctional hybrid nanoflowers by one-pot mild coprecipitation. The as-prepared HAC hybrid nanoflowers then were utilized as the signal tag in a magnetic chemiluminescence immunoassay for application in the detection of Salmonella enteritidis (S. enteritidis). The proposed method exhibited excellent detection performance in the linear range of 10-105 CFU/mL, with the limit of detection (LOD) of 10 CFU/mL. This study indicates great potential in the sensitive detection of foodborne pathogenic bacteria in milk with this new magnetic chemiluminescence biosensing platform.
Collapse
|
12
|
Yuan P, Deng Z, Qiu P, Yin Z, Bai Y, Su Z, He J. Bimetallic Metal−Organic framework nanorods with peroxidase mimicking activity for selective colorimetric detection of Salmonella typhimurium in food. Food Control 2023. [DOI: 10.1016/j.foodcont.2022.109357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
|
13
|
Song X, Wang H, Xu X. Amikacin- and AuNP-mediated colorimetric biosensor for the rapid and sensitive detection of bacteria. Lebensm Wiss Technol 2022. [DOI: 10.1016/j.lwt.2022.114189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
14
|
Tu Z, Yang X, Dong H, Yu Q, Zheng S, Cheng X, Wang C, Rong Z, Wang S. Ultrasensitive Fluorescence Lateral Flow Assay for Simultaneous Detection of Pseudomonas aeruginosa and Salmonella typhimurium via Wheat Germ Agglutinin-Functionalized Magnetic Quantum Dot Nanoprobe. BIOSENSORS 2022; 12:942. [PMID: 36354451 PMCID: PMC9687718 DOI: 10.3390/bios12110942] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 10/21/2022] [Accepted: 10/21/2022] [Indexed: 06/16/2023]
Abstract
Point-of-care testing methods for the rapid and sensitive screening of pathogenic bacteria are urgently needed because of the high number of outbreaks of microbial infections and foodborne diseases. In this study, we developed a highly sensitive and multiplex lateral flow assay (LFA) for the simultaneous detection of Pseudomonas aeruginosa and Salmonella typhimurium in complex samples by using wheat germ agglutinin (WGA)-modified magnetic quantum dots (Mag@QDs) as a universal detection nanoprobe. The Mag@QDs-WGA tag with a 200 nm Fe3O4 core and multiple QD-formed shell was introduced into the LFA biosensor for the universal capture of the two target bacteria and provided the dual amplification effect of fluorescence enhancement and magnetic enrichment for ultra-sensitivity detection. Meanwhile, two antibacterial antibodies were separately sprayed onto the two test lines of the LFA strip to ensure the specific identification of P. aeruginosa and S. typhimurium through one test. The proposed LFA exhibited excellent analytical performance, including high capture rate (>80%) to the target pathogens, low detection limit (<30 cells/mL), short testing time (<35 min), and good reproducibility (relative standard deviation < 10.4%). Given these merits, the Mag@QDs-WGA-based LFA has a great potential for the on-site and real-time diagnosis of bacterial samples.
Collapse
Affiliation(s)
- Zhijie Tu
- Beijing Institute of Microbiology and Epidemiology, Beijing 100089, China
- Medical Technology School, Xuzhou Medical University, Xuzhou 221004, China
| | - Xingsheng Yang
- Beijing Institute of Microbiology and Epidemiology, Beijing 100089, China
| | - Hao Dong
- Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230036, China
| | - Qing Yu
- Beijing Institute of Microbiology and Epidemiology, Beijing 100089, China
- College of Life Sciences, Anhui Agricultural University, Hefei 230036, China
| | - Shuai Zheng
- Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230036, China
- College of Life Sciences, Anhui Agricultural University, Hefei 230036, China
| | - Xiaodan Cheng
- Beijing Institute of Microbiology and Epidemiology, Beijing 100089, China
| | - Chongwen Wang
- Beijing Institute of Microbiology and Epidemiology, Beijing 100089, China
- Medical Technology School, Xuzhou Medical University, Xuzhou 221004, China
- College of Life Sciences, Anhui Agricultural University, Hefei 230036, China
| | - Zhen Rong
- Beijing Institute of Microbiology and Epidemiology, Beijing 100089, China
| | - Shengqi Wang
- Beijing Institute of Microbiology and Epidemiology, Beijing 100089, China
| |
Collapse
|
15
|
Xiao F, Li W, Xu H. Advances in magnetic nanoparticles for the separation of foodborne pathogens: Recognition, separation strategy, and application. Compr Rev Food Sci Food Saf 2022; 21:4478-4504. [PMID: 36037285 DOI: 10.1111/1541-4337.13023] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Revised: 07/20/2022] [Accepted: 07/25/2022] [Indexed: 01/28/2023]
Abstract
Foodborne pathogens contamination is one of the main sources of food safety problems. Although the existing detection methods have been developed for a long time, the complexity of food samples is still the main factor affecting the detection time and sensitivity, and the rapid separation and enrichment of pathogens is still an objective to be studied. Magnetic separation strategy based on magnetic nanoparticles (MNPs) is considered to be an effective tool for rapid separation and enrichment of foodborne pathogens in food. Therefore, this study comprehensively reviews the development of MNPs in the separation of foodborne pathogens over the past decade. First, various biorecognition reagents for identification of foodborne pathogens and their modifications on the surface of MNPs are introduced. Then, the factors affecting the separation of foodborne pathogens, including the size of MNPs, modification methods, separation strategies and separation forms are discussed. Finally, the application of MNPs in integrated detection methods is reviewed. Moreover, current challenges and prospects of MNPs for the analysis of foodborne pathogens are discussed. Further research should focus on the design of multifunctional MNPs, the processing of large-scale samples, the simultaneous analysis of multiple targets, and the development of all-in-one small analytical device with separation and detection.
Collapse
Affiliation(s)
- Fangbin Xiao
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, P. R. China
| | - Weiqiang Li
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, P. R. China
| | - Hengyi Xu
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, P. R. China
| |
Collapse
|
16
|
Jaisankar A, Krishnan S, Rangasamy L. Recent developments of aptamer-based lateral flow assays for point-of-care (POC) diagnostics. Anal Biochem 2022; 655:114874. [PMID: 36027971 DOI: 10.1016/j.ab.2022.114874] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 08/08/2022] [Accepted: 08/19/2022] [Indexed: 12/11/2022]
Abstract
In the field of lateral flow assay (LFA), the application of aptamer as a bioreceptor has been implemented to overcome the limitations of antibodies, such as tedious in vivo processes, short shelf-life, and functionalization issues. To address these limitations aptamer-based LFA (ALFA) is preferred to antibody-based LFA that produces higher sensitivity and specificity. In principle, aptamers have a strong affinity towards their targets like small, large, and non-immunogenic molecules because of their high affinity, sensitivity, low dissociation constant, cost-effectiveness, and flexible nature. Thus, ALFA can be considered an efficient biosensor model for its superior portability, rapid detection with quick turnaround time, and usability by a non-technical person at any location with simple visual output. This review concisely overviews ALFA, its principles, formats, aptamer selection process, and biomedical applications. In addition, the critical components to design, develop, test, and amplify signals to create ALFA are discussed in brief. In addition, the aspects of conceptualization of ALFA product transforming from bench-side laboratory design and fabrication to commercial market are addressed in detail.
Collapse
Affiliation(s)
- Abinaya Jaisankar
- Drug Discovery Unit, Centre for Biomaterials, Cellular, and Molecular Theranostics (CBCMT), Vellore Institute of Technology (VIT), Vellore, 632014, Tamil Nadu, India
| | - Sasirekha Krishnan
- Drug Discovery Unit, Centre for Biomaterials, Cellular, and Molecular Theranostics (CBCMT), Vellore Institute of Technology (VIT), Vellore, 632014, Tamil Nadu, India
| | - Loganathan Rangasamy
- Drug Discovery Unit, Centre for Biomaterials, Cellular, and Molecular Theranostics (CBCMT), Vellore Institute of Technology (VIT), Vellore, 632014, Tamil Nadu, India.
| |
Collapse
|
17
|
Zhang D, Wang J. Editorial to Special Issue-Research on Isolation and Intelligent Detection Methods of Foodborne Pathogens. Foods 2022; 11:foods11091213. [PMID: 35563936 PMCID: PMC9103726 DOI: 10.3390/foods11091213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 04/20/2022] [Indexed: 01/27/2023] Open
Abstract
Foodborne illnesses pose a significant threat worldwide to public health [...].
Collapse
|
18
|
Aptamer-Based Lateral Flow Assays: Current Trends in Clinical Diagnostic Rapid Tests. Pharmaceuticals (Basel) 2022; 15:ph15010090. [PMID: 35056148 PMCID: PMC8781427 DOI: 10.3390/ph15010090] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 01/09/2022] [Accepted: 01/10/2022] [Indexed: 12/18/2022] Open
Abstract
The lateral flow assay (LFA) is an extensively used paper-based platform for the rapid and on-site detection of different analytes. The method is user-friendly with no need for sophisticated operation and only includes adding sample. Generally, antibodies are employed as the biorecognition elements in the LFA. However, antibodies possess several disadvantages including poor stability, high batch-to-batch variation, long development time, high price and need for ethical approval and cold chain. Because of these limitations, aptamers screened by an in vitro process can be a good alternative to antibodies as biorecognition molecules in the LFA. In recent years, aptamer-based LFAs have been investigated for the detection of different analytes in point-of-care diagnostics. In this review, we summarize the applications of aptamer technology in LFAs in clinical diagnostic rapid tests for the detection of biomarkers, microbial analytes, hormones and antibiotics. Performance, advantages and drawbacks of the developed assays are also discussed.
Collapse
|
19
|
Chen S, Zong X, Zheng J, Zhang J, Zhou M, Chen Q, Man C, Jiang Y. A Colorimetric Strategy Based on Aptamer-Catalyzed Hairpin Assembly for the On-Site Detection of Salmonella typhimurium in Milk. Foods 2021; 10:foods10112539. [PMID: 34828820 PMCID: PMC8623332 DOI: 10.3390/foods10112539] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Revised: 10/15/2021] [Accepted: 10/19/2021] [Indexed: 12/19/2022] Open
Abstract
Salmonella typhimurium (S. typhimurium) is a foodborne pathogen that has caused numerous outbreaks worldwide, necessitating the development of on-site strategy to prevent early contamination. Here, we set up an enzyme-free strategy for aptamer-catalyzed hairpin assembly in which salt-induced aggregation of unmodified gold nanoparticles (AuNPs) served as a colorimetric signal output, allowing on-site detection of S. typhimurium in milk. The aptamer-functionalized magnetic beads were used as a vehicle of specifically enriching target bacteria which conjugated with target aptamer to trigger the “Y” shape catalytic hairpin assembly (Y-CHA) circuit. Due to the hairpins desorbing from the surface of AuNPs to the formation of a large amount of double-stranded DNA (dsDNA), AuNPs turned from dispersion to aggregation in the presence of S. typhimurium, resulting in a change of the colorimetric signal from red to blue-gray. The signal output showed a linear relationship for S. typhimurium over a concentration range of 102 to 106 CFU/mL, with a sensitivity of 2.4 × 102 CFU/mL under optimal conditions. The visual protocol has excellent selectivity even in the presence of other competitive bacteria and has been validated in real milk samples with a sensitivity of 2.8 × 103 CFU/mL.
Collapse
|