TalantaPub Date : 2025-01-01Epub Date: 2024-09-25DOI: 10.1016/j.talanta.2024.126944
Yu Shi, Jirui Yu, Yanxi Song, Ji Fan, Xiwen Wang, Shiji Li, Hongqi Li
{"title":"Multifunctional near-infrared fluorescent probe for sensing of lysine and Cu<sup>2+</sup>/Fe<sup>3+</sup> and relay detection of biothiols.","authors":"Yu Shi, Jirui Yu, Yanxi Song, Ji Fan, Xiwen Wang, Shiji Li, Hongqi Li","doi":"10.1016/j.talanta.2024.126944","DOIUrl":"10.1016/j.talanta.2024.126944","url":null,"abstract":"<p><p>Lysine (Lys), Cu<sup>2+</sup> and Fe<sup>3+</sup> ions and biothiols are essential to a myriad of biological and pathological pathways, and their dysregulation is implicated in a variety of diseases. Development of fluorescent probes capable of detecting multiple analytes may be of great significance for early and accurate diagnosis of diseases and remains a huge challenge. In this context, a novel coumarin-dicyanoisophorone-based probe, engineered for the concurrent sensing of Lys, Cu<sup>2+</sup>, Fe<sup>3+</sup> and biothiols was developed. The probe exhibited turn-on response to Lys, colorimetric and turn-off response to Cu<sup>2+</sup> by formation of the probe-Cu<sup>2+</sup> complex, and ratiometric sensing of Fe<sup>3+</sup>. In addition, the probe-Cu<sup>2+</sup> complex served colorimetric and fluorescence turn-on sensor for biothiols. The limit of detection (LOD) values for the analytes were in the range of 0.30-4.40 μM. Sensing mechanisms based on intramolecular charge transfer (ICT) and iron-mediated hydrolysis of Schiff base were proposed and substantiated through density functional theory (DFT) calculations. Application of the probe for living cell bioimaging was demonstrated.</p>","PeriodicalId":435,"journal":{"name":"Talanta","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142338760","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TalantaPub Date : 2025-01-01Epub Date: 2024-09-14DOI: 10.1016/j.talanta.2024.126896
Sarmento J Mazivila, Jose X Soares, Rui A S Lapa, M Lúcia M F S Saraiva, Jose O Fernandes, Sara C Cunha, Joao L M Santos
{"title":"PARAFAC under non-negativity constraint is adapted to recover the underlying Beer-Lambert law of the excitation-emission fluorescence matrix measurements acquired from analyte-triggered semiconductor QDs photoluminescence modulation. When and why?","authors":"Sarmento J Mazivila, Jose X Soares, Rui A S Lapa, M Lúcia M F S Saraiva, Jose O Fernandes, Sara C Cunha, Joao L M Santos","doi":"10.1016/j.talanta.2024.126896","DOIUrl":"10.1016/j.talanta.2024.126896","url":null,"abstract":"<p><strong>Background: </strong>Analyte-triggered semiconductor quantum dots (QDs) modulation in the presence of non-consistently responsive fluorescent species represents a challenging analytical issue in concrete multi-way data handling. QDs with heterogeneous sizes and/or uneven distribution of functional moieties on their surfaces exhibit significant fluctuations in the fluorescent response components, known as chemical rank, across different excitation/emission modes. This phenomenon may lead to a substantial deviation from the proportionality prescribed by Beer-Lambert law. Nonetheless, even in the presence of such deviation, a multi-way model may be successfully selected after determining a proper chemical rank in a QDs system.</p><p><strong>Results: </strong>We show that in a valid PARAllel FACtor (PARAFAC) model under properly determined chemical rank, meaningfully resolved pure spectral profiles can be reached for each fluorescent responsive constituent in the original excitation-emission fluorescence matrix (EEFM) measurements. This was thoroughly illustrated by applying PARAFAC trilinear decomposition of a three-way data array of two distinct datasets acquired from semiconductor QDs sensing systems with low-rank trilinear assumption. The first dataset, presented here for the first time, comprises EEFM measurements of the ligand-driven quenching of thiomalic acid (TMA)-capped AgInS<sub>2</sub> (AIS) QDs by vomitoxin. The second dataset, employed for illustrative purposes, comprises EEFM measurements of the quenching, via cation bridging, of glutathione (GSH)-capped CdTe QDs by Pb(II). The results of this study enabled the determination of vomitoxin at a ppb level in real samples of fish feeds, showcasing the efficacy of the PARAFAC model in resolving spectral signatures (loadings) and pure concentration profiles (scores).</p><p><strong>Significance: </strong>PARAFAC under a properly examined chemical rank can be easily adapted for retrieval the underlying Beer-Lambert law of the original EEFM measurements with a low-rank trilinear structure through the chemically meaningful information either when (i) no deviation of Beer-Lambert law was observed as deeply discussed in connection with the dataset acquired from vomitoxin-driven molecular sensing through TMA-capped AIS QDs, or when (ii) substantial deviations of the Beer-Lambert law are evident, as discussed in connection with the dataset collected from sensing ionic species through Pb(II) bridging of GSH-capped CdTe QDs.</p>","PeriodicalId":435,"journal":{"name":"Talanta","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142338763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TalantaPub Date : 2025-01-01Epub Date: 2024-09-19DOI: 10.1016/j.talanta.2024.126910
Guangyao Li, Jieqing Li, Honggao Liu, Yuanzhong Wang
{"title":"Rapid and accurate identification of Gastrodia elata Blume species based on FTIR and NIR spectroscopy combined with chemometric methods.","authors":"Guangyao Li, Jieqing Li, Honggao Liu, Yuanzhong Wang","doi":"10.1016/j.talanta.2024.126910","DOIUrl":"10.1016/j.talanta.2024.126910","url":null,"abstract":"<p><p>Different varieties of Gastrodia elata Blume (G. elata Bl.) have different qualities and different contents of active ingredients, such as polysaccharide and gastrodin, and it is generally believed that the higher the active ingredients, the better the quality of G. elata Bl. and the stronger the medicinal effects. Therefore, effective identification of G. elata Bl. species is crucial and has important theoretical and practical significance. In this study, first unsupervised PCA and t-SNE are established for data visualisation, follow by traditional machine learning (PLS-DA, OPLS-DA and SVM) models and deep learning (ResNet) models were established based on the fourier transform infrared (FTIR) and near infrared (NIR) spectra data of three G. elata Bl. species. The results show that PLS-DA, OPLS-DA and SVM models require complex preprocessing of spectral data to build stable and reliable models. Compared with traditional machine learning models, ResNet models do not require complex spectral preprocessing, and the training and test sets of ResNet models built based on raw NIR and low-level data fusion (FTIR + NIR) spectra reach 100 % accuracy, the external validation set based on low-level data fusion reaches 100 % accuracy, and the external validation set based on NIR has only one sample classification error and no overfitting.</p>","PeriodicalId":435,"journal":{"name":"Talanta","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142278359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A tunable LDI-MS platform assisted by metal-phenolic network-coated AuNPs for sensitive and customized detection of amino acids.","authors":"Tong Hu, Qi Sang, Dingyitai Liang, Wenjing Zhang, Yuning Wang, Kun Qian","doi":"10.1016/j.talanta.2024.126928","DOIUrl":"10.1016/j.talanta.2024.126928","url":null,"abstract":"<p><p>This study introduces a novel approach for the sensitive and accurate detection of small molecule metabolites, employing metal-phenolic network (MPN) functionalized AuNPs as both adsorbent and matrix to enhance laser desorption/ionization mass spectrometry (LDI-MS) performance. The MPN comprising tannic acid (TA) and transition metal ions (Fe<sup>3+</sup>, Co<sup>2+</sup>, Ni<sup>2+</sup>, Cu<sup>2+</sup>, or Zn<sup>2+</sup>) was coated on the surface of AuNPs, forming metal-TA network-coated AuNPs (M-TA@AuNPs). The M-TA@AuNPs provided a tunable surface for specific interactions with analytes, displaying distinct enrichment efficacies for different amino acids, especially for Cu-TA@AuNPs exhibiting the highest affinity for histidine (His). Under the optimized condition, the proposed method enabled ultrasensitive detection of His, with good linearity (R<sup>2</sup> = 0.9627) in the low-concentration range (50 nM-1 μM) and a limit of detection (LOD) as low as 0.9 nM. Furthermore, the method was successfully applied to detect His from human urine samples, showcasing its practical applications in clinical diagnostics, particularly in the realm of amino acid-based targeted metabolomics.</p>","PeriodicalId":435,"journal":{"name":"Talanta","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142338750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TalantaPub Date : 2025-01-01Epub Date: 2024-09-25DOI: 10.1016/j.talanta.2024.126903
Rafael C Hensel, Biagio Di Vizio, Elsa M Materòn, Flávio M Shimizu, Monara Kaelle S C Angelim, Gabriela F de Souza, José L P Módena, Pedro M M Moraes-Vieira, Ricardo B de Azevedo, Lucio Litti, Stefano Agnoli, Stefano Casalini, Osvaldo N Oliveira
{"title":"Enhanced performance of impedimetric immunosensors to detect SARS-CoV-2 with bare gold nanoparticles and graphene acetic acid.","authors":"Rafael C Hensel, Biagio Di Vizio, Elsa M Materòn, Flávio M Shimizu, Monara Kaelle S C Angelim, Gabriela F de Souza, José L P Módena, Pedro M M Moraes-Vieira, Ricardo B de Azevedo, Lucio Litti, Stefano Agnoli, Stefano Casalini, Osvaldo N Oliveira","doi":"10.1016/j.talanta.2024.126903","DOIUrl":"10.1016/j.talanta.2024.126903","url":null,"abstract":"<p><p>Immunosensors based on electrical impedance spectroscopy allow for label-free, real-time detection of biologically relevant molecules and pathogens, without requiring electro-active materials. Here, we investigate the influence of bare gold nanoparticles (AuNPs), synthesized via laser ablation in solution, on the performance of an impedimetric immunosensor for detecting severe acute respiratory syndrome coronavirus (SARS-CoV-2). Graphene acetic acid (GAA) was used in the active layer for immobilizing anti-SARS-CoV-2 antibodies, owing to its high density of carboxylic groups. Immunosensors incorporating AuNPs exhibited superior performance compared to those relying solely on GAA, achieving a limit of detection (LoD) of 3 x 10<sup>-20</sup> g/mL to detect the Spike Receptor Binding Domain (RBD) protein of SARS-CoV-2 and of 2 PFU/mL for inactivated virus. Moreover, these immunosensors presented high selectivity against the H1N1 influenza virus. We anticipate that this platform will be versatile and applicable in the early diagnosis of various diseases and viral infections, thereby facilitating Point-of-Care testing.</p>","PeriodicalId":435,"journal":{"name":"Talanta","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142338755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jae Hwan Shin, Navnath S Padalkar, Hyo Jeong Yang, Jayshri A Shingade, Jong Pil Park
{"title":"Affinity peptide-based electrochemical biosensor with 2D-2D nanoarchitecture of nickel-chromium-layered double hydroxide and graphene oxide nanosheets for chirality detection of symmetric dimethylarginine.","authors":"Jae Hwan Shin, Navnath S Padalkar, Hyo Jeong Yang, Jayshri A Shingade, Jong Pil Park","doi":"10.1016/j.bios.2024.116871","DOIUrl":"10.1016/j.bios.2024.116871","url":null,"abstract":"<p><p>The accurate assessment of kidney dysfunction is crucial in clinical practice, necessitating the exploration of reliable biomarkers. However, current methods for measuring SDMA often fall short in terms of sensitivity and specificity. In this study, we employed phage display technology to identify high affinity peptides that specifically bind to SDMA. The selected peptide was subsequently integrated into a novel Ni-Cr layered double hydroxide-graphene oxide (NCL-GO) nanoarchitecture. We characterized the electrochemical properties of the biosensor using cyclic voltammetry, electrochemical impedance spectroscopy and differential pulse voltammetry, systematically evaluating critical parameters such as limit of detection (LOD), reproducibility, and performance in complex biological matrices including urine. The NCL-GO architecture not only enhances the surface area available for electrochemical reactions but also facilitates rapid electron transfer kinetics which are essential for the accurate quantification of small molecule, SDMA. The electrochemical biosensor exhibited an outstanding limit of detection of 0.1 ng/mL in the 0-1 ng/mL range and 7.2 ng/mL in the 1-100 ng/mL range, demonstrating exceptional sensitivity and specificity for SDMA. Furthermore, the biosensor displayed excellent reproducibility with a relative standard deviation of 4.9%. Notably, it maintained robust chirality sensing capabilities, even in complex biological fluids. These findings suggest that this biosensor could play a pivotal role in early disease diagnosis and therapeutic monitoring, ultimately improving clinical outcomes and advancing biomedical research.</p>","PeriodicalId":259,"journal":{"name":"Biosensors and Bioelectronics","volume":null,"pages":null},"PeriodicalIF":10.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142491901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Qianqian Li, Shengfan Chen, Huawei Wang, Qiaoying Chang, Yi Li, Jianxun Li
{"title":"Decoding wheat contamination through self-assembled whole-cell biosensor combined with linear and non-linear machine learning algorithms.","authors":"Qianqian Li, Shengfan Chen, Huawei Wang, Qiaoying Chang, Yi Li, Jianxun Li","doi":"10.1016/j.bios.2024.116869","DOIUrl":"10.1016/j.bios.2024.116869","url":null,"abstract":"<p><p>The contamination of mycotoxins is a serious problem around the world. It has detrimental effects on human beings and leads to tremendous economic loss. It is essential to develop a rapid and non-destructive method for contamination recognition particularly for early alarm. In this study, the whole-cell biosensor array was constructed and employed for rapid recognition of wheat contamination by combining with machine learning algorithms. Seven key VOCs were explored through univariate coupling to multivariate analysis of orthogonal partial least squares-discrimination analysis (OPLS-DA) models. The promoters of dnaK, katG, oxyR, soxS obtained from the stress-responsive of key VOCs were fused to the bacterial operon and fabricated on the whole-cell biosensor. The constructed whole-cell biosensor array was consisted with four kinds of sensors and 18 sensor unit. The bioluminescent intensity combined with linear machine learning algorithm of partial least squares discriminant analysis (PLS-DA) and non-linear algorithms of back propagating artificial neural network (BP-ANN) and least square support vector machine (LS-SVM) were employed to establish discrimination models for mold contamination especially for early warning. The Monte-Carlo strategy was performed to generate thirty subsets for modeling to give more reliable results. As a result, the whole-cell biosensor combined with non-linear algorithm of LS-SVM was practicable for detecting mold identification for wheat early-warning with the accuracy of 97.24%. Additionally, this study provides practical and effective methods not only for wheat quality guarantee and supervision but also for other foodstuffs.</p>","PeriodicalId":259,"journal":{"name":"Biosensors and Bioelectronics","volume":null,"pages":null},"PeriodicalIF":10.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142491902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Minsu Park, Chan-Hyeong Lee, Hyowoong Noh, Geeyoon Kang, Junyeong Lee, Ju-Hyun Bae, Hyeri Moon, Jonghoo Park, Seongho Kong, Moon-Chang Baek, Hongsik Park
{"title":"High-precision extracellular-vesicle isolation-analysis integrated platform for rapid cancer diagnosis directly from blood plasma.","authors":"Minsu Park, Chan-Hyeong Lee, Hyowoong Noh, Geeyoon Kang, Junyeong Lee, Ju-Hyun Bae, Hyeri Moon, Jonghoo Park, Seongho Kong, Moon-Chang Baek, Hongsik Park","doi":"10.1016/j.bios.2024.116863","DOIUrl":"10.1016/j.bios.2024.116863","url":null,"abstract":"<p><p>Cancer-derived small extracellular vesicles (sEVs) in body fluids hold promise as biomarkers for cancer diagnosis. For sEV-based liquid biopsy, isolation of sEVs with a high-purity and cancer-sEV detection with an extremely high sensitivity are essential because body fluids include much higher density of normal-cell-derived sEVs and other biomolecules and bioparticles. Here, we propose an isolation-analysis-integrated cancer-diagnosis platform based on dielectrophoresis(DEP)-ELISA technique which enables a three orders of magnitude higher sensitivity over conventional ELISA method and direct cancer diagnosis from blood plasma with high accuracy. The limit of detection (LOD) for sEVs in human plasma was as low as 10<sup>4</sup> sEVs/mL without a time-consuming and low-yield sEV isolation and purification process. The capability of this platform was validated by monitoring mice with cancer cell inoculation and assessing the effect of cancer-sEV-inhibiting drug. Using the developed sEV-based liquid biopsy, we diagnosed clinical samples from healthy donors (N = 39) and cancer patients (N = 90). The diagnostic accuracy was 94.2%, 98.6%, and 91.3% for breast, colon, and lung cancers, respectively. This integrated sEV isolation and analysis platform could be applied for high-sensitivity biomarker profiling and sEV-based liquid biopsy.</p>","PeriodicalId":259,"journal":{"name":"Biosensors and Bioelectronics","volume":null,"pages":null},"PeriodicalIF":10.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142491916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nan Hai, Han Yi, Yining Bai, Lingyun Zhang, Haonan Chi, Jiajing Yan, Longshan Zhao, Shuang Cai
{"title":"HOF-derived Step-Scheme FJU-200@CdSe heterojunction: A photoelectrochemical sensing platform for sensitive detection of EGFR.","authors":"Nan Hai, Han Yi, Yining Bai, Lingyun Zhang, Haonan Chi, Jiajing Yan, Longshan Zhao, Shuang Cai","doi":"10.1016/j.bios.2024.116862","DOIUrl":"10.1016/j.bios.2024.116862","url":null,"abstract":"<p><p>Here, a photoelectrochemical (PEC) immunosensor based on the FJU-200@CdSe heterostructure was developed for epidermal growth factor receptor (EGFR) detection. This is the first application of FJU-200 in PEC. After modification using CdSe quantum dots (QDs), FJU-200 and CdSe QDs formed an S-scheme heterostructure due to the interleaved energy band structure and the difference in Fermi energy (Ef) levels, which generated an efficient and stable PEC signal. When EGFR bound specifically to the antibody, a large spatial site resistance was generated, which hindered the electron transfer at the interface and the PEC signal was quenched. The proposed PEC sensing platform exhibited excellent detection performance for EGFR, with a good linear relationship with the photocurrent change value (ΔI) in the detection range of 10 fg/mL-100 ng/mL, and the detection limit was as low as 1.08 fg/mL. This work illustrates the potential electron transfer pathway between FJU-200 and CdSe QDs and creatively applies to the construction of PEC immunosensors, providing a new option for the detection of EGFR as well as other substances to be tested.</p>","PeriodicalId":259,"journal":{"name":"Biosensors and Bioelectronics","volume":null,"pages":null},"PeriodicalIF":10.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142491917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Enhanced trans-cleavage activity using CRISPR-Cas12a variant designed to reduce steric inhibition by cis-cleavage products.","authors":"Injoo Hwang, Yo Han Song, Sanghwa Lee","doi":"10.1016/j.bios.2024.116859","DOIUrl":"10.1016/j.bios.2024.116859","url":null,"abstract":"<p><p>The CRISPR-Cas12a system has emerged as a promising tool for molecular diagnostics due to its indiscriminate trans-ssDNase activity. However, the sensitivity of Cas12a-based diagnostics remains insufficient for clinical use without a pre-amplification step such as loop-mediated isothermal amplification, and therefore the trans-cleavage activity of Cas12a needs to be enhanced. Here, we present a novel strategy to enhance the trans-cleavage activity of Cas12a by reducing the steric hindrance from cis-cleavage products. We have designed Cas12a variants with alanine mutations in the target strand loading (TSL) domain, resulting in reduced affinity for target strand (TS) overhangs to the catalytic site and significantly increased trans-cleavage efficiency by up to 5.8-fold. In addition, we used a novel salt dilution method to exploit the enhanced trans-cleavage activity of Cas12a under low ionic strength conditions (7-fold), significantly improving the sensitivity of our Cas12a-based detection system. To demonstrate the clinical potential of our Cas12a-based detection system, we validated its ability to detect small amounts of hepatitis B virus (HBV) DNA model using the combination of the KE1096AA Cas12a mutant and the salt dilution method, which enables the detection of DNA at atto-molar concentrations. Our strategy to enhance the trans-cleavage activity of Cas12a paves the way for the development of more sensitive and efficient Cas12a-based diagnostics.</p>","PeriodicalId":259,"journal":{"name":"Biosensors and Bioelectronics","volume":null,"pages":null},"PeriodicalIF":10.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142454495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}