SCIENCE OF THE TOTAL ENVIRONMENT
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2024
·
IF 8.2
Lin Zhu,Wei Zeng,Yueqing Li,Yu Han,Jing Wei,Long Wu
In this work, on the basis of Fe 3 O 4 @Au-Pt nanozymes (MAP NZs) and aptamer recognition, a magnetic fluorescent aptasensor (MFA) was developed for sensitive and accurate detection of saxitoxin (STX). With the bridge of STX aptamer (Apt STX ) and complementary DNA (cDNA), Apt STX decorated MAP NZs (MAP/Apt) and cDNA modified green quantum dots (cDNA@g-QDs) were connected to form MAP/Apt-cDNA@g-QDs complex. As STX behaves a strong binding ability towards Apt STX , it will compete with cDNA and hybridize with Apt to release cDNA@g-QDs. With the addition of TMB, MAP will catalyze TMB to the oxidized TMB (ox-TMB), thereby quenching the fluorescence of g-QDs due to the inner filter effect. Based on this finding, the quantitative relationship between the change in fluorescence of gQDs and STX concentration was explored with a limit of detection (LOD, S/N = 3) of 0.6 nM. An internal standard signal of oxTMB was adopted and reduced the fluctuation of fluorescence signal output. Besides, the fluorescence probe can selectively recognize and detect STX among five marine toxins. Eventually, the MFA method behaved good performance in detecting seafood samples with recoveries of 82.0 % ∼ 102.6 % as well as coefficient of variations (CV) of 7.2 % ∼ 10.3 %. Therefore, the method with internal signal is hopeful to be a potential candidate for sensitive and accurate detection of STX in seafood.
研究领域:
分析化学
·
食品安全检测
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanomaterials
·
2022
·Vol. 12
·期 9
·1505
·
IF 5.719
Najeeb Ullah,Beenish Noureen,Yulan Tian,Liping Du,Wei Chen,Chunsheng Wu
Saxitoxin (STX) is a highly toxic and widely distributed paralytic shellfish toxin (PSP), posing a serious hazard to the environment and human health. Thus, it is highly required to develop new STX detection approaches that are convenient, desirable, and affordable. This study presented a label-free electrolyte-insulator-semiconductor (EIS) sensor covered with a layer-by-layer developed positively charged Poly (amidoamine) (PAMAM) dendrimer. An aptamer (Apt), which is sensitive to STX was electrostatically immobilized onto the PAMAM dendrimer layer. This results in an Apt that is preferably flat inside a Debye length, resulting in less charge-screening effect and a higher sensor signal. Capacitance-voltage and constant-capacitance measurements were utilized to monitor each step of a sensor surface variation, namely, the immobilization of PAMAM dendrimers, Apt, and STX. Additionally, the surface morphology of PAMAM dendrimer layers was studied by using atomic force microscopy and scanning electron microscopy. Fluorescence microscopy was utilized to confirm that Apt was successfully immobilized on a PAMAM dendrimer-modified EIS sensor. The results presented an aptasensor with a detection range of 0.5–100 nM for STX detection and a limit of detection was 0.09 nM. Additionally, the aptasensor demonstrated high selectivity and 9-day stability. The extraction of mussel tissue indicated that an aptasensor may be applied to the detection of STX in real samples. An aptasensor enables marine toxin detection in a rapid and label-free manner.Keywords:electrolyte-insulator-semiconductor sensor;aptamer;PAMAM dendrimer;saxitoxin;marine toxins
研究领域:
生物传感器
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毒理学
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分析化学
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海洋科学
✓ 已验证
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Liu-Na Wei,Lin Luo,Hong-Tao Lei,Tian Guan,Cheng Jiang,Qing-Chun Yin,Zhen-Lin Xu,Chenzhong Li
Investigating organic carriers’ utilization efficiency and bioactivity within organic–inorganic hybrid nanoflowers is critical to constructing sensitive immunosensors. Nevertheless, the sensitivity of immunosensors is interactively regulated by different classes of biomolecules such as antibodies and enzymes. In this work, we introduced a new alkaline phosphatase–antibody–CaHPO4 hybrid nanoflowers (AAHNFs) microreactor based colorimetric immunoprobe. This system integrates a biometric unit (antibody) with a signal amplification element (enzyme) through the biomineralization process. Specifically, the critical factors affecting antibody recognition activity in the formation mechanism of AAHNFs are investigated. The designed AAHNFs retain antibody recognition ability with enhanced protection for encapsulated proteins against high temperature, organic solvents, and long-term storage, facilitating the selective construction of lock structures against antigens. Additionally, a colorimetric immunosensor based on AAHNFs was developed. After ascorbic acid 2-phosphate hydrolysis by alkaline phosphatase (ALP), the generated ascorbic acid decomposes I2 to I–, inducing the localized surface plasmon resonance in the silver nanoplate, which is effectively tuned through shape conversion to develop the sensor. Further, a 3D-printed portable device is fabricated, integrated with a smartphone sensing platform, and applied to the data of collection and analysis. Notably, the immunosensor exhibits improved analytical performance with a 0.1–6.25 ng·mL–1 detection range and a 0.06 ng·mL–1 detection limit for quantitative saxitoxin (STX) analysis. The average recoveries of STX in real samples ranged from 85.9% to 105.9%. This study presents a more in-depth investigation of the recognition element performance, providing insights for improved antibody performance in practical applications.
研究领域:
生物化学
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生物技术
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分析化学
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纳米技术
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TALANTA
·
2021
·
IF 6.057
Beenish Noureen,Najeeb Ullah,Yulan Tian,Liping Du,Wei Chen,Chunsheng Wu,Ping Wang
Saxitoxin (STX), is one of the most dangerous and widespread paralytic shellfish toxins , causing a severe threat to the ecosystem and human health. So, it is important and highly essential to develop novel techniques for STX detection in a convenient, desirable, and low-cost manner. Herein, this study developed an electrolyte-insulator-semiconductor (EIS) sensor covered with a layer-by-layer prepared, positively-charged weak polyelectrolyte layer of poly (allylamine hydrochloride) (PAH) for the label-free detection of STX. The specific aptamer (Apt) sensitive to STX was electrostatically adsorbed onto the PAH layer. This leads to a preferentially flat orientation of the Apt within the Debye length, thus yielding a reduced charge-screening influence and a higher sensor signal. Each step of sensor surface modification, i.e. PAH adsorption, immobilization of Apt, and attachment of STX, was monitored by capacitance-voltage ( C - V ) and constant-capacitance (ConCap) measurements. Furthermore, atomic force microscopy (AFM) was employed to characterize the surface morphology and roughness of the PAH layer. Fluorescence microscopy was used to confirm the effective immobilization of Apt onto the PAH-modified EIS sensor. The results showed that the detection range of this aptasensor for STX detection was 0.5–100 nM and the detection limit was as low as 0.05 nM. Furthermore, this aptasensor showed good selectivity and 9 days’ stability. The mussel tissue extraction test suggested that this aptasensor can be used to detect STX in real samples. This aptasensor provides a convenient approach for moderate, rapid, and label-free detection of marine biological toxins .
研究领域:
分析化学
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环境科学
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毒理学
·
生物传感器
✓ 已验证
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2021
·
IF 7.514
Mingming Yin,Weijie Wang,Jie Wei,Xiaomei Chen,Quansheng Chen,Xi Chen,Munetaka Oyama
In this work, we present a novel dual-emissive fluoroimmunoassay for synchronous monitoring of okadaic acid (OA) and saxitoxin (STX) using multicolor fluorescent labels composed of sulfur, phosphorous co-doped graphene quantum dots (S, P-GQDs), and ovalbumin (OVA)-coated gold nanoparticles (OVA-AuNPs). The novel OVA-AuNPs were prepared by the reduction of chloroauric acid under alkaline conditions using OVA as a reducing agent. Both S, P-GQDs and OVA-AuNPs exhibit bright fluorescence, more importantly, a large emission wavelength difference (Δλ = 156 nm) under an excitation of 400 nm and relatively independent fluorescence behavior, which are essential to realizing the dual-signal marks in a directly mixing system. Using a competitive fluorescence-linked immunosorbent assay (cFLISA) format, the dual-emissive cFLISA was successfully utilized to measure OA and STX contents in Alectryonella plicatula (commonly named as fingerprint oyster) and the detection results were in good agreement with the commercial enzyme-linked immunosorbent assay (ELISA) kits.
研究领域:
分析化学
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毒理学
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环境科学
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海洋生物学
✓ 已验证
DOI
高影响因子
Current Analytical Chemistry
·
2023
·Vol. 19
·期 9
·677-684
·
IF 1.8
Ullah Najeeb,Noureen Beenish,Zahra Qurat Ul A.,Aziz Tariq,Shehzadi Somia,Alfaifif Mohammad Y.,Elbehairif Serag Eldin I.,Thebo Khalid Hussain,Ullah Asmat,Iqbal Haroon
Background: Saxitoxin (STX) stands as one of the most potent marine biotoxins, exhibiting high lethality. Despite its severity, current treatments remain ineffective, and existing detection techniques are limited due to ethical concerns and technical constraints. Methods: Herein,
an innovative approach was constructed for STX detection, utilizing mesoporous silica nanoparticles (MSN) as a foundation. This innovative, easy, and label-free aptamer (Apt)- sensor was fabricated. Apts were employed as molecular identification probes and "gated molecules," while rhodamine
6G was encapsulated within particles to serve as a signal probe. In a lack of STX, Apts immobilized on an MSN surface kept a "gate" closed, preventing signal probe leakage. Upon the presence of STX, the "gate" opened, allowing a particular binding of Apts to STX and a subsequent release of
a signal probe. Results: Experimental results demonstrated a positive correlation between fluorescence intensity and concentrations of STX within a range of 1 to 80 nM, with an exceptional limit of detection of 0.12 nM. Furthermore, the selectivity and stability of a biosensor were rigorously
evaluated, validating its reliability. Conclusion: This newly developed sensing strategy exhibits remarkable performance in STX detection. Its success holds significant promise for advancing portable STX detection equipment, thereby addressing a pressing need for efficient and ethical
detection methods in combating marine biotoxin contamination.
研究领域:
分析化学
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毒理学
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海洋生物学
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纳米技术
✓ 已验证
DOI
高影响因子
Toxins
·
2025
·Vol. 17
·期 9
·430
·
IF 4
Yi Jiao,Liqing Yang,Junping Hao,Yuhang Wen,Jianhua Wang,Hengchao E,Zhiyong Zhao,Yufeng Chen,Xianli Yang
Saxitoxin (STX) is a toxin with paralyzing and lethal properties, necessitating the development of a simple analytical method. This study developed a nucleic acid aptamer biosensor using graphene oxide (GO) as a fluorescence quencher for STX detection. GO was combined with M30-f, an STX nucleic acid aptamer modification with 5-carboxyfluorescein, which can produce fluorescence absorption under the conditions of an excitation wavelength of 408 nm and emission wavelength of 515 nm. Based on the principle of fluorescence resonance energy transfer, the fluorescence of M30-f was quenched. In the presence of STX, M30-f specifically binds to STX and dissociates from the GO surface, thereby restoring fluorescence. The STX content can be quantitatively detected through differences in fluorescence absorption. The influence of ultrasonic time on the fluorescence quenching ability of GO was investigated. The aqueous solution of graphene oxide, 30GO, optimized by ultrasound treatment for a duration of 30 min, demonstrated excellent fluorescence quenching capability. 30GO was analyzed utilizing various characterization techniques, including SEM, FT-IR, UV, XPS, XRD, AFM, and contact angle measurements. The methodological validation showed that the established STX sensor exhibits excellent linearity within a concentration range of 10–100,000 ng/L, with a limit of detection (LOD) as low as 0.098 μg/L. In addition, the results further demonstrated the sensor’s high specificity for detecting neurotoxic shellfish toxin STX. The recovery rate for clam samples ranged from 89.12% to 104.71%, while that for oyster samples ranged from 91.20% to 109.65%, with relative standard deviations (RSDs) all below 3%. This aptamer sensor is characterized by its simplicity, high sensitivity, and broad detection range, providing significant technical support for advancing marine biotoxin research.
研究领域:
分析化学
·
环境毒理学
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海洋生物学
·
食品安全
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生物传感器
·
分子识别
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ELECTROPHORESIS
·
2016
·
IF 2.482
Ye He,Fan Mo,Danlong Chen,LiangJun Xu,Yongning Wu,FengFu Fu
As one of paralytic shellfish toxins, the saxitoxin (STX) in the aqueous environment can be accumulated by most shellfish, and thus harms human health through the food chain. Therefore, it is crucial to determine trace STX in seafood samples in order to ensure the safety of seafood consumption. In this study, we developed a novel indirect method for ultrasensitively determining trace STX in seafood by using CE-ICP-MS together with Eu 3+ chelate labeling. We demonstrated that diethylenetriamine- N , N , N ′, N ″, N ″-pentaacetic acid (DTPA) can couple with STX and simultaneously chelate with Eu 3+ to realize metallic labeling of STX, and thus realize the ultrasensitive quantification of trace STX with CE-ICP-MS. The proposed method has strong antiinterference ability, good stability, and extremely high sensitivity. It could be used to determine trace STX in seafood samples with an extremely low detection limit of 0.38 fmol (3.8×10 −9 M, 100 nL sample injection) and a relative standard deviation (RSD, n = 5) <7%. The success of this study provides an alternative to precise quantification of ultra-trace STX in seafood samples, and further expands the application of ICP-MS.
研究领域:
食品安全
·
分析化学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF FOOD COMPOSITION AND ANALYSIS
·
2024
·
IF 4
Long Wu,Yueqing Li,Yu Han,Xing Liu,Bingjun Han,Haimei Mao,Qi Chen
Saxitoxin (STX), one of paralytic shellfish poison neurotoxins with high toxicity, posing a significant threat to seafood safety. Therefore, it is of great need to protect human health by screening STX contaminated seafood samples. In this study, to achieve specificity for STX, molecularly imprinted polymers (MIP) were fabricated on Au-Pt nanoparticles modified Fe 3 O 4 magnetic nanozymes (MS@Au-Pt NZs) with numerous memory cavities (MS@Au-Pt/MIP), which catalyzed the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB). STX will occupy the recognition cavity of MIP and obstruct the catalytic site of MS@Au-Pt, thus hindering the color development reaction, and the oxidized TMB (oxTMB) can be measured by Raman spectroscopy and recorded with Raman signals. Under the optimal conditions, the MIDMs method obtained a wide linear range for colorimetric assay (0.01 μM to 100 μM) and Raman detection (0.1 nM to 100 nM), with limits of detection (3σ/S, n=3) of 3.1 nM and 0.03 nM, respectively. As a proof-of-concept, the approach showed acceptable recoveries of 78.0∼96.2% in real samples of mussel and clam. The dual-mode optical sensor, therefore, is hopeful to be a potential candidate for sensitive and accurate detection of STX in seafood.
研究领域:
分析化学
·
食品安全
·
纳米技术
·
毒理学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）