JOURNAL OF MOLECULAR STRUCTURE
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2024
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IF 4
Yuyang Luo,Shiyu Zheng,Congcong Dong,Haojie Yu,Kunming Liu,Juanhua Li,Jinbiao Liu
An innovative dual-modal colorimetric and fluorometric probe MDXM is synthesized based on the dihydro-1 H -xanthene motif via Knoevenagel reaction. The incorporation of a malononitrile group into the dihydro-1 H -xanthene motif via a double bond results in an extensive macroconjugated π-system, which endows MDXM with a pronounced molar absorptivity and effectively quenches the intramolecular charge transfer (ICT) effect. Upon exposure to hypochlorite, the C = C bond in MDXM undergoes cleavage, resulting in the formation of an aldehyde group. This process restores the ICT effect and manifests as a clear fluorescent ''turn-on'' signal at 530 nm, with a remarkably linear response across the ClO − concentration range of 0–60 μM. The probe achieves a notably low detection limit of 7.14 nM, reflecting its exceptional sensitivity. In the presence of 15 common metal ions and oxidizing agents, MDXM can specifically identify hypochlorite with excellent anti-interference ability. The response mechanism of MDXM to hypochlorite was confirmed through Nuclear Magnetic Resonance (NMR) spectroscopy and computational Density Functional Theory (DFT) calculations. The practical applicability of MDXM is underscored by its successful implementation in analyzing hypochlorite in 5 varied real water samples. This showcases MDXM' s promise for environmental and analytical chemistry, providing a robust tool for hypochlorite detection in diverse settings.
研究领域:
分析化学
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环境科学
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生物医学
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产品关联
DOI
高影响因子
Food Frontiers
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2023
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IF 9.9
Yaru Li,Jiali Qiao,Zhiying Zhao,Qiang Zhang,Wenlu Zhang,Shuli Man,Shengying Ye,Kai Chen,Long Ma
It is imperative to develop practicable pathogenic bacteria detection methods. We devised a biosensor for the ultrasensitive detection of Salmonella typhimurium ( S. typhi ), termed as SCOUT-dCas9 (ultrasensitive, cross-validating, on-site, and dUal-mode test using CRISPR/dCas9). Simply, the species-specific invA gene of S. typhi was amplified using loop-mediated isothermal amplification with a biotinylated primer, which can be specifically “pulled down” by “antibody-like” dCas9-single guide RNA to form a ternary complex. SYBR Green I and streptavidin-modified alkaline phosphatase were used to functionalize them to generate fluorescent and colorimetric signals, respectively. With this strategy, the target could be dexterously converted into bimodal signals that were cross-validated to afford more reliable results. For both modes, SCOUT-dCas9 was able to detect as low as 1 CFU/mL with a dynamic range from 1 to 10 9 CFU/mL. Lastly, SCOUT-dCas9 had satisfactory selectivity and was capable of detecting S. typhi -contaminated real food samples. SCOUT-dCas9 provides a robust platform for bacterial detection.
研究领域:
生物技术
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微生物学
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食品科学
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DOI
高影响因子
ANALYTICAL SCIENCES
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2024
·Vol. 40
·期 8
·1459-1473
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IF 1.8
Xu Xin,Zhang Ze,Shen Tong,Pan Hongzhi,Chang Dong
The main reason for the high mortality rate of non-small cell lung cancer is that patients are usually diagnosed at an advanced stage of the disease. Exosomes, small membrane vesicles secreted by normal cells or tumor cells, play a significant role in the progression of NSCLC. This study successfully optimized the preparation of artificial nanoenzymes self-coupling with horseradish peroxidase (IrO 2 NPs@HRP-AptCD63), without adding any ligand, demonstrating remarkable catalytic activity suitable for detecting the EGFR protein on the surface of NSCLC exosomes. When fused with the CD63 aptamer for identifying NSCLC exosomes, IrO 2 NPs@HRP showed enhanced catalytic activity in the 3,3′,5,5′-tetramethylbenzidine-H 2 O 2 oxidation–reduction system, thereby enhancing the colorimetric signal. This phenomenon can be distinguished by the naked eye and quantified using a UV–Vis spectrophotometer. Meanwhile, as the redox reaction occurs, the current signal of 3,3′,5,5′-tetramethylbenzidine-H 2 O 2 , acting as an electrolyte, changes. The developed aptasensor generates dual-mode signal outputs, firstly, to visually assess the samples for their positive or negative status, and subsequently employ more in-depth electrochemical or colorimetric analysis methods for a detailed quantitative analysis of suspected positive samples. The detection limits of electrochemical analysis and colorimetric analysis were 0.9 × 10 3 particles/mL and 0.14 × 10 3 particles/mL, respectively. Compared with traditional biomarkers such as CA125, this method exhibits exceptional specificity, capable of simultaneously distinguishing serum exosomes of healthy volunteers, COPD patients, and NSCLC patients, promoting exosome detection in mouse models for tumor monitoring. Additionally, it elucidates the changes in EGFR protein expression on the surface of serum exosomes throughout the developmental trajectory. Graphical abstract
研究领域:
癌症生物学
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纳米技术
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生物传感器
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分子诊断
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产品关联
DOI
PubMed
高影响因子
TALANTA
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2023
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IF 6.1
Jing Xu,Yinbing Liu,Ke-Jing Huang,Renjie Wang,Xiaoxuan Sun
We report here for the first time a self-powered biosensing platform based on graphene/graphdiyne/graphene (GDY-Gr) heterostructure substrate material for ultrasensitive hepatocarcinoma marker (microRNA-21) detection in both electrochemical and colorimetric test modes. The dual-mode signal intuitively displayed on a smartphone fundamentally improves the detection accuracy. In electrochemical mode, the calibration curve is established in the linear range of 0.1–10000 fM, and the detection limit is as low as 0.333 fM (S/N = 3). Simultaneously, colorimetric analysis of the miRNA-21 is realized by using ABTS as an indicator. The detection limit is confirmed as 32 fM (S/N = 3), and miRNA-21 of concentration from 0.1 pM to 1 nM exhibit a linear relationship with R2 = 0.9968. Overall, the combination of GDY-Gr and multiple signal amplification strategy significantly improved the sensitivity by 310 times compared with traditional enzymatic biofuel cells (EBFCs) based detection platform, showing broad application prospects for on-site analysis and future mobile medical services.
研究领域:
生物传感器
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癌症诊断
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纳米材料
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电化学
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即时检测
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产品关联
DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
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2021
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IF 10.618
Wan Huang,Danyan Zhan,Yiming Xie,Xin Li,Guosong Lai
DNA walkers have been recognized as a type of powerful signal amplification tool for biosensors, but how to adopt a proper strategy to increase their amplification efficiency is still highly desirable. Herein we design a dual-catalytic hairpin assembly (CHA)-mediated strategy for the high-efficient formation of a tripedal Mg 2+ -dependent DNAzyme (MNAzyme)-DNA walker, and thus develop a novel proteinase-free dual-mode biosensing method for the kanamycin (Kana) antibiotic assay. The first CHA is initiated by a target-biorecognition reaction, which can produce the DNA walker and also induce the target recycling. The second CHA is initiated by a special base sequence designed as a one-half substrate of the MNAzyme. Upon the first CHA-triggered DNA walking at a magnetic bead (MB) track, this “pseudo-target” sequence can be released to induce another CHA-cycle for the formation of the same DNA walker. Meanwhile, the other one-half substrate strand exposed on the MB surface will trigger the quantitative hybridization chain reaction (HCR)-assembly of a G-quadruplex DNAzyme (G-DNAzyme)-enriched double-stranded DNA polymer. So the enzymatic reaction of G-DNAzymes enabled the convenient colorimetric and photoelectrochemical dual-mode signal transduction of the method. Due to the dual-CHA facilitation to the tripedal and three-dimensional DNA walking and synergetic signal amplification of HCR, this method exhibits very low detection limits of 9.4 and 0.55 fg mL −1 , respectively. In combination with its wide linear range, automated manipulation, and excellent selectivity , repeatability and reliability, the proposed method is expected to be used for the convenient semiquantitative screening and accurate determination of possible antibiotic residues in complicated matrices.
研究领域:
生物化学
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分析化学
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生物传感器
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纳米技术
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产品关联
DOI
PubMed
高影响因子
Science China-Materials
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2023
·Vol. 66
·期 7
·2843-2851
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IF 8.1
Xia Shan,Fu Wei,Liu Jiahao,Gao Guanghui
Ionic conductive hydrogels have emerged as one of the most promising alternatives to wearable sensors for human motion detecting, owing to their unique advantages in biocompatibility, conductivity and flexibility. However, the current hydrogel electronics still face the limitations of non-reusability and single-signal detection capability. Here, an ionic conductive hydrogel based on polyvinyl alcohol, sodium alginate fibers, and collagen was prepared by simulating the network structure and ion conduction mechanism of organisms for dual-mode signal acquisition of human motion and electrophysiological signals. Through the synergistic regulation of sodium alginate fibers and collagen, the hydrogels exhibit skin-like mechanical properties with low modulus, high toughness, and fatigue resistance to maximize the wearing comfort and motion detection capabilities of hydrogel wearable sensors. Furthermore, the hydrogel conductors with ion-transporting behavior close to organisms can be used as epidermal electrodes to collect the epidermis biopotential containing important human physiological information. As a result, through the rational design and assembly of wearable devices, hydrogels can be used to not only continuously and accurately identify whole-body motion signals, but also collect different electrophysiological signals such as electromyogram and electrocardiogram signals. Notably, the hydrogel based on the non-covalent cross-linked structure is completely recyclable, which can be arbitrarily reconstituted into new electronic devices while retaining the original function, improving the reusability of the hydrogels and reducing electronic waste.
研究领域:
材料科学
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生物医学工程
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可穿戴技术
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可持续电子
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）