FOOD CHEMISTRY
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2020
·
IF 6.306
Min Jia,Junyi Sha,Zhihua Li,Wenjing Wang,Hongyan Zhang
The widespread exposure of bisphenol A (BPA) presents a significant risk to human health. A rapid, ultra-sensitive and label-free colorimetric aptasensor using high affinity truncated aptamers was developed for BPA detection. Truncated 38-mer and 12-mer aptamers specific for BPA were obtained through rationally truncation from 63-mer BPA aptamer. The dissociation constants ( K d ) of 38-mer and 12-mer aptamers were determined to be 13.17 nM and 27.05 nM. Then, truncated aptamers were used in label-free colorimetric detection assays based on gold nanoparticles (AuNPs). The limit of detections of aptasensors using 38-mer and 12-mer aptamers were 7.60 pM and 14.41 pM, which were 265-fold and 140-fold lower than that of the aptasensor using 63-mer aptamer, respectively. The recovery rates in milk, orange juice and mineralized water samples were 93.88% to 107.30%. Therefore, the developed BPA colorimetric aptasensor using truncated aptamers has great application prospects in food safety control and environmental monitoring.
研究领域:
分析化学
·
环境科学
·
食品安全
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产品关联
DOI
PubMed
高影响因子
Animal Diseases
·
2022
·Vol. 2
·期 1
·1-9
·
IF 0
Lu Ying,Liu Zehui,Li Yingxiang,Deng Zhuofan,Fang Weihuan,He Fang
Porcine circovirus type 2 (PCV2) is the main causative agent of porcine circovirus-associated diseases, and it causes substantial economic losses in the swine industry each year. It is crucial to develop an effective vaccine against the circulating strain PCV2d, which is prone to substantial degrees of mutation. In this study, a truncated form of flagellin (tFlic: 85-111 aa) was inserted into the C-terminal sequence of 2dCap, and Western blotting results showed that recombinant Cap-tFlic VLPs were successfully expressed. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) data indicated that purified recombinant Cap-tFlic fusion proteins existed in the form of polymers and that tFlic could not affect the formation and internalization of VLPs. Integrated Cap-tFlic VLPs induced the expression of antigen presentation-related factors (MHC-II and CD86) by bone marrow-derived dendritic cells (BM-DCs), and the expression of TLR5-related factors (TNF-α) was dramatically elevated. Mice intramuscularly immunized with Cap-tFlic VLPs exhibited significantly higher levels of Cap-specific antibodies and neutralizing antibodies than mice immunized with wild-type Cap VLPs. The data obtained in the current study indicate that Cap-tFlic may be a candidate for a subunit vaccine against PCV2 in the future.
研究领域:
兽医学
·
免疫学
·
病毒学
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DOI
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
·
2012
·Vol. 97
·期 3
·1113-1120
·
IF 3.425
Jia Dongxu,Li Jianghua,Liu Long,Zhang Dongxu,Yang Yu,Du Guocheng,Chen Jian
A 1,965-bp fragment encoding a poly(vinyl alcohol) dehydrogenase (PVADH) from Sphingopyxis sp. 113P3 was synthesized based on the codon bias of the methylotrophic yeast Pichia pastoris . The fragment was then amplified by polymerase chain reaction and inserted into the site between Eco RI and Not I sites in pPIC9K, which was under the control of the AOX1 promoter and α-mating factor signal sequence from Saccharomyces cerevisiae . The recombinant plasmid, designated as pPIC9K-PVADH, was linearized using Sal I and transformed into P. pastoris GS115 by electroporation. The PVADH activity reached 55 U/mL in a shake flask and 902 U/mL in a 3-L bioreactor. Surprisingly, the sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis and N-terminal sequencing indicated that the secreted PVADH was truncated, and it had only 548 amino acid residues (an 81-amino acid sequence from the secreted protein was cleaved). The optimum pH and temperature ranges for the truncated PVADH were 7.0–8.0 and 41–53 °C, respectively. The activation energy of the recombinant truncated PVADH was approximately 10.36 kcal/mol between 29 and 41 °C. Both Ca 2+ and Mg 2+ had stimulating effects on the activity of PVADH. With PVA1799 as the substrate, the truncated PVADH had a Michaelis constant ( K
m ) of 1.89 mg/mL and a maximum reaction rate ( V
max ) of 34.9 nmol/(min mg protein). To the best of our knowledge, this is the first report on the expression of PVADH in P. pastoris , and the achieved PVADH yield is the highest ever reported.
研究领域:
生物化学
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分子生物学
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微生物学
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DOI
PubMed
高影响因子
ANALYTICAL LETTERS
·
2023
·
IF 2
Liran Tian,Xiangwei Song,Tianjiao Liu,Anfeng Li,Yang Ning,Xiuyi Hua,Deming Dong,Zhijun Song,Dapeng Liang
Acetamiprid is mainly used to control pests. However, the residues of acetamiprid have resulted in significant negative effects on mammals. Many researchers are working on developing acetamiprid detection methods. In our study, four truncated aptamers were designed based on the secondary structure of the original aptamer. Molecular docking simulation of truncated aptamers confirmed that all of the truncated aptamers bind to acetamiprid, and their binding sites were identified. The affinity, sensitivity, and specificity of these truncated aptamers were measured by a spectrophotometric method with gold nanoparticles (AuNPs). Acetamiprid aptamers with 17-mer (Apt-J2) and 16-mer (Apt-J4) were successfully obtained, which show higher detection sensitivity and satisfactory specificity. Additionally, a spectrophotometric detection route superior to the original aptamer was explored, and the linear ranges were from 1 to 70 μM and 0.5 to 40 μM, respectively. The truncated aptamers were applied to the analysis of lake water, indicating that the aptamers have potential for practical analysis.
研究领域:
分析化学
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环境科学
·
分子生物学
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产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2024
·
IF 4.9
Hanbing Jiang,Yijie Liu,Chunhua Tang,Zheng Wei,Meilun Chen,Xiaoling Lu,Jie Yang,Peng Yu
This study introduces a novel E2 (17β-estradiol) colorimetric sensor constructed using a truncation optimization strategy of the nucleic acid aptamer. Systematic truncation of the 17β-estradiol nucleic acid aptamer was performed, leading to the design and evaluation of a series of aptamer variants with different lengths to enhance their structural stability and synthesis efficiency. Through a series of experiments, the binding affinities of these truncated aptamer variants with E2 were compared, resulting in the selection of an optimal aptamer, E12. Aptamer E12, chosen through this process, was successfully applied in a gold nanoparticle-based colorimetric assay, enabling susceptible and specific detection of E2. Our research not only presents a simple and cost-effective method for E2 detection but also provides new insights into the truncation optimization strategy of nucleic acid aptamers. The developed E2 colorimetric sensor exhibits outstanding specificity and sensitivity and holds great promise for applications in environmental pollution detection.
研究领域:
生物化学
·
环境科学
·
分析化学
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产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2020
·
IF 6.306
Lu Qiao,He Wang,Junlin He,Shuming Yang,Ailiang Chen
17β-estradiol (E2) residues could enrich in organisms via food chain and lead to harmful biological effects for human body. To ascertain the binding domain of original E2 aptamer (E00) with long-sequence (76-mer), we developed novel truncated aptamers from E00, through rationally designed truncation by intercepting a single ring or a combination of rings (containing hairpin loop, interior loop or multiloop) at different sites and retaining appropriate double helix regions. Through comparison, 15-mer E09 presented improved affinity and higher specificity, indicating the hairpin loop near to 3′ end of E00 served on the binding domain to E2. E09 was used for gold nanoparticles (AuNPs)-based colorimetric determination of E2, achieved the detection limit of 0.02 μg/mL. The truncated aptamer (only 15-mer) first proposed in this study has great application potential in E2 determination, and this work provides proof-of-concept study for truncation of other long-sequence aptamers.
研究领域:
分析化学
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纳米技术
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生物技术
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产品关联
DOI
PubMed
高影响因子
Food Analytical Methods
·
2022
·Vol. 15
·期 8
·2202-2212
·
IF 3.498
Feng Junli,Wu Yuanyuan,Shen Qing
In the present study, a sensitive and simple approach for colorimetric detecting microcystin-LR (MC-LR) in fish tissue was developed based on gold nanoparticles (AuNPs) and a truncated aptamer Apt-910–2, which was obtained by mutation and rational truncation from the previously selected 60-mer one. The 23-mer Apt-910–2 presented improved binding affinity to MC-LR and higher specificity. Under the optimum experimental conditions, the Apt-910–2 colorimetric aptasensor worked well in 10 to 150 ng/mL MC-LR concentration ranges, and the limit of detection (LOD) was 0.38 ng/mL. This Apt-910–2 colorimetric aptasensor was also applied to spiked fish tissue samples and gave recovery rates ranged from 75.18 to 87.72%, with the visual LOD 10 μg/kg in fish tissue judged by the naked eye. Thus, this study provides a rapid, reliable, and convenient approach for visual detection of MC-LR, which is of great significance for food safety control by assessing potential health risks related to seafood consumption.
研究领域:
环境科学
·
分析化学
·
食品安全
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产品关联
DOI
高影响因子
ANALYST
·
2019
·Vol. 144
·期 12
·3826-3835
·
IF 4.019
Xinglin Wang,Xiaoyi Gao,Jiale He,Xiaochen Hu,Yunchao Li,Xiaohong Li,Louzhen Fan,Hua-Zhong Yu
Graphene oxide (GO)-based aptasensors are currently one of the most popular sensing platforms for the simple and rapid detection of various targets. Unfortunately, the GO-based aptasensors with long aptamer strands typically show unsatisfactory performance resulting from insignificant structural transformations upon target binding. We report herein the utilization of an aptamer-truncating strategy to combat such a challenge. Taking a pre-selected anti-aflatoxin B1 (AFB1) aptamer (P-AFB1-50) as a trial system, we sequentially remove the extraneous nucleotides within the aptamer by means of circular dichroism (CD) spectroscopy and binding affinity analysis. Particularly, the ratio of the quenching constants between the GO sheets and the truncated aptamers (labelled with fluorophores) in the absence and presence of the target was determined for each of the truncated aptamers to evaluate the optimal sequence. As a result, the truncated aptamer comprising 40 nucleotides was confirmed to show the highest FL output and the best detection limit upon conjugation with GO sheets. More importantly, we demonstrated that this truncating strategy is versatile, i.e., it can be easily extended to other aptamer systems (anti-ochratoxin A (OTA) aptamer, P-OTA-61, as an example) for extraneous nucleotide identification. Impressively, the two optimal truncated aptamers can work together on GO sheets to achieve a simultaneous detection of two different mycotoxins (i.e., AFB1 and OTA) in one single test. Essentially, this research opens a new avenue for the design and testing of aptamer-/GO-based-sensing platforms for rapid, low-cost and multiplex quantification of analytical targets of interest.
研究领域:
分析化学
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生物传感器
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毒理学
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产品关联
DOI
PubMed
高影响因子
ADVANCED MATERIALS
·
2021
·Vol. 33
·期 34
·2101707
·
IF 30.849
Min Li,Sanpeng Li,Yixuan Huang,Haixia Chen,Songya Zhang,Zhicheng Zhang,Weigang Wu,Xiaobin Zeng,Boping Zhou,Bin Li
The transfer of foreign synthetic messenger RNA (mRNA) into cells is essential for mRNA-based protein-replacement therapies. Prophylactic mRNA COVID-19 vaccines commonly utilize nanotechnology to deliver mRNA encoding SARS-CoV-2 vaccine antigens, thereby triggering the body's immune response and preventing infections. In this study, a new combinatorial library of symmetric lipid-like compounds is constructed, and among which a lead compound is selected to prepare lipid-like nanoassemblies (LLNs) for intracellular delivery of mRNA. After multiround optimization, the mRNA formulated into core–shell-structured LLNs exhibits more than three orders of magnitude higher resistance to serum than the unprotected mRNA, and leads to sustained and high-level protein expression in mammalian cells. A single intravenous injection of LLNs into mice achieves over 95% mRNA translation in the spleen, without causing significant hematological and histological changes. Delivery of in-vitro-transcribed mRNA that encodes high-affinity truncated ACE2 variants (tACE2v mRNA) through LLNs induces elevated expression and secretion of tACE2v decoys, which is able to effectively block the binding of the receptor-binding domain of the SARS-CoV-2 to the human ACE2 receptor. The robust neutralization activity in vitro suggests that intracellular delivery of mRNA encoding ACE2 receptor mimics via LLNs may represent a potential intervention strategy for COVID-19.
研究领域:
纳米技术
·
分子生物学
·
药学
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病毒学
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治疗学
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产品关联
DOI
PubMed
高影响因子
Journal of Biomedical Nanotechnology
·
2022
·Vol. 18
·期 11
·2498-2507
·
IF 3.641
Yang Jie,Hou Yucui,Ren Yi,Tang Chunhua,Li HuanHuan,Huang Jing,Jiang Hanbing,Cai Tongji,Zhao Jia,Yu Peng
This study built an electrochemical label-free progesterone aptasensor to detect progesterone (P4) levels in environmental water samples. The truncated aptamer-modified sulfhydryl adopted self-assembly as a way to stably immobilize at the electrode surface modified by gold nanoparticles
(AuNPs). When progesterone combines with the aptamer, the complexes will inhibit electrode surface electron transfer, which reduces the redox peak current value of [Fe(CN)6]3−/4−. As a result, the amount of progesterone combined with the aptamer on the electrode
reacted to the electric current’s response values. We have established the relationship between the concentration of progesterone and the current change by a standard curve that is ΔI (μA) = 11.78log CP4 (nM)+48.98. The coefficient of association was 0.9358.
The test ranges were from 0.5 nM to 1000 nM. At the same time, other molecules with a similar structure, such as testosterone, estradiol, and 17α-hydroxyl progesterone, had lower response interference than P4. In conclusion, the aptasensor, which had outstanding repeatability
and stability, could be applied to determine P4. Food hygiene and clinical diagnosis can be made easier with this newly developed electrochemical biosensor based on aptamers.
研究领域:
分析化学
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环境科学
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生物传感器
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电化学
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DOI
高影响因子
Biosensors-Basel
·
2022
·Vol. 12
·期 7
·513
·
IF 5.743
Xingyue Chen,Lulan Yang,Jiaming Tang,Xu Wen,Xiaoling Zheng,Lingling Chen,Jiaqi Li,Yong Xie,Tao Le
Herein, we developed a novel truncation technique for aptamer sequences to fabricate highly sensitive aptasensors based on molecular docking and molecular dynamics simulations. The binding mechanism and energy composition of the aptamer/sulfaquinoxaline (SQX) complexes were investigated. We successfully obtained a new SQX-specific aptamer (SBA28-1: CCCTAGGGG) with high affinity (Kd= 27.36 nM) and high specificity determined using graphene oxide. This aptamer has a unique stem-loop structure that can bind to SQX. Then, we fabricated a fluorescence aptasensor based on SBA28-1, gold nanoparticles (AuNPs), and rhodamine B (RhoB) that presented a good linear range of 1.25–160 ng/mL and a limit of detection of 1.04 ng/mL. When used to analyze water samples, the aptasensor presented acceptable recovery rates of 93.1–100.1% and coefficients of variation (CVs) of 2.2–10.2%. In conclusion, the fluorescence aptasensor can accurately and sensitively detect SQX in water samples and has good application prospects.Keywords:molecular docking;molecular dynamics simulations;aptamer truncation;fluorescence aptasensor;gold nanoparticles
研究领域:
分析化学
·
环境科学
·
纳米技术
·
生物化学
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产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Xin Zheng,Yajing Ji,Shengjie Li,Siyao Liu
The sensing of phthalate esters (PAEs) is vital for people’s health and environmental protection. This study aimed to develop a highly sensitive and selective photoelectrochemical (PEC) biosensor for PAEs analysis in complex samples. The biosensor is based on a CdS nanoparticle/TiO2 nanotube (CdS NP/TiO2 NT) electrode substrate and a truncated PAEs aptamer (PAEs-apt). By exploiting spatial variations in the potential resistance of the sensing interface, the biosensor achieved superior sensitivity in determining the concentration of PAEs compared to the SELEX aptamer. It exhibited a linear correlation in the range of 0.005 to 1 ng/mL with a detection limit of 1.67 ng/L. Furthermore, the biosensor displayed excellent selectivity for PAEs, with an analysis error factor below 0.277 when the concentration of interfering species was 100 times that of the target. The high performance of the biosensor was attributed to the excellent photoelectronic properties of CdS NPs/TiO2 NTs, high density of PAEs-apt for PAEs, high affinity of PAEs-apt for PAEs, and specific recognition of PAEs. Notably, this PEC biosensor could be used for the PAEs assay in urine and water samples, providing a sensitive and simple analytical method for detecting the same class of compounds with similar chemical structures in complex samples.
研究领域:
环境科学
·
分析化学
·
生物传感器
·
材料科学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）