Journal of Immunotoxicology
·
2022
·
IF 3.439
Wenhua Zhong,Penghuan Chang,Lianfang Gan,Lifan Zhong,Zhaoxin Yang
Most current methods to assess T-cell-dependent antibody responses (TDAR) are semi-quantitative and based on measures of antibody titer generated against a standard antigen like keyhole limpet hemocyanin (KLH). The precision, sensitivity, and convenience of TDAR assays might be improved by applying rapid, sensitive, specific cytometric bead assays (CBA). In the study here, KLH antigen was covalently coupled onto the surface of cytometric beads using immune microsphere technology, and IgM antibody capture spheres were prepared for use in pretreatment processing of samples. The working parameters associated with this novel TDAR-CBA system were optimized in orthogonal experiments. The optimal concentration of the KLH coating solution in this system was 160 μg/ml, that of the anti-KLH IgG capture spheres 6.0 × 105/ml, and the optimal dilution of fluorescein isothiocyanate (FITC)-conjugated Affini-Pure Goat Anti-Mouse IgG (H + L) was 60 μg/ml. Repeated tests indicated that this approach yielded good linearity (r2 = 0.9937) method, with a within-run precision of 3.1–4.9%, and a between-run precision of 4.4–4.9%. This new approach had a limit of detection of 113.43 ng/ml (linear range = 390.63–50 000), and an interference rate of just 0.04–3.51%. Based on these findings, it seems that a new mouse TDAR assay based on CBA can be developed that would appear to be more sensitive, accurate, and precise than the current TDAR assay approaches based on traditional ELISA.
研究领域:
免疫学
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分子生物学
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分析化学
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DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2020
·
IF 5.162
Fenfen Li,Pengcheng Du,Weiyu Yang,Danfei Huang,Shaoping Nie,Mingyong Xie
The intestinal epithelium is known as an important barrier to protect the body from harmful pathogens or toxic substance that may induce intestinal barrier injury. The aim of this study was to investigate the effects of polysaccharide from the seeds of Plantago asiatica L. (PLP) on nonylphenol (NP) induced intestinal barrier injury in vitro . Caco-2 cells were pretreated with PLP, or co-cultured with PLP and NP simultaneously, and cytotoxicity, LDH leakage, transepithelial electrical resistance (TEER), FITC-dextran flux and tight junction (TJ) proteins were conducted to evaluate the intestinal barrier function. The results suggested that PLP pretreatment or co-culture with NP could significantly attenuated NP induced Caco-2 cytotoxicity, suppressed LDH release, restored the TEER value and paracellular permeability of Caco-2 monolayers, which were attributed to enhancing the TJ protein expressions. In addition, PLP co-cultured with NP possessed better protective effects against NP induced cytotoxicity. This study indicated that PLP assuaged NP induced intestinal barrier injury by increasing TJ, and threw light on the development of a dietary supplementation for preventing exogenous toxic substances induced intestinal barrier injury or improving intestinal TJ barrier function.
研究领域:
药理学
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毒理学
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细胞生物学
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胃肠病学
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PubMed
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2023
·Vol. 34
·期 7
·2340-2354
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IF 3.4
Ping Zhang,Chaoqun Zhang,Jie Song,Shuxin Wang,Qian Li,Feng Su,Suming Li
A novel nanoprobe was developed for the detection of hyaluronidase as cancer marker, using fluorescein 5-isothiocyanate (FITC) as fluorescence indicator, hyaluronic acid (HA), and polyethyleneimine (PEI) functionalized graphene oxide (GO) as quencher. PEI was attached to GO through amide bonding, using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and N -hydroxysuccinimide (NHS) as coupling agents. Aminated hyaluronic acid (HA) was then linked to GO-PEI (GOP) via the same route. Nuclear magnetic resonance, ultraviolet–visible–near infrared spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscope, and thermogravimetric analysis analyses confirmed the successful synthesis of GOP-HA. Finally, FITC was attached to GOP-HA through reaction between the isothiocyanate group of FITC and the amine group of aminated HA. The fluorescence of FITC is quenched in the resulted GOP-HA-FITC nanoprobe. Addition of hyaluronidase can cleave HA chains into small fragments, releasing FITC to emit fluorescence. Importantly, the nanoprobe is highly sensitive and selective, and can enter cells by specifically binding to the CD44 receptor on the surface of Hela cells. Therefore, GOP-HA-FITC nanoprobe could be used in targeted tumor cell imaging for the early diagnosis of cancers.
研究领域:
纳米技术
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生物医学工程
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癌症研究
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分子生物学
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材料科学
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DOI
高影响因子
ANALYTICA CHIMICA ACTA
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2019
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IF 5.256
Yu Cai,Ji-Cheng Niu,Yu-Qi Liu,Xin-Li Du,Zhi-Yong Wu
Paper-based analytical device (PAD) has received more and more attention in the field of point-of-care test (POCT) due to its low cost, portability and simple operation. Sensitivity and selectivity are two important aspects in clinical diagnostic analysis. However, low sensitivity of a PAD limits its wider application for POCT. Here we introduced a PAD that can clean and enrich the protein content from salty media with both electric field (E) and pH gradient (double E/pH gradients), with which 100-fold enrichment effect could be achieved within 70 s as demonstrated by fluorescein isothiocyanate labeled bovine serum albumin (FITC-BSA) from artificial urine media. With post staining of the protein stacking band with bromophenol blue (BPB), selective colorimetric detection of human serum albumin (HSA) was achieved simply with smartphone camera in the clinically significant range of 10–300 mg‧L −1 (R 2 = 0.99) with a limit of detection (LOD) of 4.9 mg‧L −1 . Detection of microalbuminuria (MAU) of diabetic patients was demonstrated with this method without difference (ɑ = 0.01) to that by the clinical method (immunoturbidimetry). This work demonstrated the potential of this PAD method in online sample pretreatment and detection of target component from complex physiological samples.
研究领域:
分析化学
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生物医学工程
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临床诊断
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DOI
PubMed
高影响因子
TALANTA
·
2019
·
IF 4.916
Yang Xing,Ying Zhou,Li Fan,Yajuan Yang,Yuan Zhang,Xu Deng,Chuan Dong,Shaomin Shuang
Herein, we figured out a novel ratiometric fluorescent probe based on Janus silica nanoparticles (SiO 2 NPs) where fluorescein isothiocyanate (FITC) and rhodamine B (RB) were asymmetrically functionalized for intracellular pH detection. With this unique strategy, the probe exhibited dual emission bands at 530 and 580 nm upon excitation at a single wavelength of 488 nm. The pH titrations of the probe showed a remarkable increase in ratiometric intensities ratio (I 530nm /I 580nm ) when the pH was switched from 3.0 to 8.0 with a acid dissociation constant (pKa) value of 6.64. The probe was successfully applied to imaging and detection of pH in living cells without noticeable cytotoxicity, indicating that it is a promising candidate for bioanalysis and bioimaging.
研究领域:
纳米技术
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生物化学
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生物医学工程
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细胞生物学
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产品关联
DOI
PubMed
高影响因子
American Journal of Translational Research
·
2022
·
IF 3.94
Hui Yu,Ruxin Zheng,Fei Lei,Wanyue Wang,Weikang Guo,Lu Zhang,Yunduo Liu,Xiuwei Chen,Yaoxian Wang
This study aimed to synthesize silica-coated gold (Au@SiO 2 ) nanoparticles coupled to antibodies against the scavenger receptor class B type I (SR-BI) and investigate their potential ability of visual tracking and treatment of cervical cancer. The fluorescein isothiocyanate (FITC)-labeled Au@SiO 2 -SR-BI antibody was synthesized, followed by characterization determination. The expression and location of SR-BI protein in cervical cancer cells were respectively detected by western blot and immunofluorescence assays. The effects of nanoparticles on cancer cells were determined by adsorption assay and apoptosis detection, respectively. The effects of nanoparticles on tumor formation in nude mice were determined. The particle sizes of Au@SiO 2 ranged from 2-2.5 μm, and the particle size distribution was relatively uniform. MS751 showed the highest expression of SR-BI. SR-BI was located in the cytomembrane. There were more FITC-Au@SiO 2 -SR-BI nanoparticles on the surface of the cells compared to FITC-Au@SiO 2 . Significant apoptosis was observed in the FITC-Au@SiO 2 -SR-BI-treated group in both MS751 and H8 cells. Photothermal ablation of solid tumors was observed when FITC-Au@SiO 2 -SR-BI was activated using 808 nm wave. Expressions of the apoptosis-related markers including BCL2, BCLX, and p-AKT were significantly decreased, while those of caspase 3 and caspase 8 were significantly increased. The study presented a novel antibody-conjugated Au@SiO 2 nanoparticle specifically targeting molecular receptors on cancer cell membranes. Antibody-conjugated Au@SiO 2 nanoparticles may have therapeutic potential for the treatment of cervical cancer.
研究领域:
纳米技术
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癌症研究
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生物医学工程
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分子生物学
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DOI
PubMed
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2020
·Vol. 167
·期 14
·147520
·
IF 3.721
Xinyi Wang,Liubing Kong,Shuqi Zhou,Tao Liang,Hao Wan,Ping Wang
Photoluminescence (PL) sensors based on quantum dots (QDs) are difficult to achieve exact detection in sample waters. In this paper, polyvinyl alcohol (PVA) based CdTe/ZnS/CdS QDs and fluorescein isothiocyanate (FITC) fluorophores were used to build a ratiometric PL sensor. Combining with the homemade smartphone-based PL E-eye, the Cd2+ exact detection can be achieved. PVA was used to connect QDs and FITC fluorophores without unnecessary ligand exchange and purification. For QDs fluorophore, ethylenediaminetetraaceticacid (EDTA) was used on the surface to induce the specifically Cd2+ recognition site. For FITC fluorophore, the PL remains unchanged in this experiment. Thus, the ratio of two fluorophores can be used to provide a built-in correction. The PL changes with the increase of Cd2+ concentrations could be displayed as a visual color change on the smartphone. Further quantitative analysis could be carried out by the RGB value of the picture through the App in less than 1 min The ratio of R/G is linear to Cd2+ concentration in the range of 1–2000 μg l−1 with a low LOD of 0.057 μg l−1 (S/N). Compared with traditional analysis methods, the PL ratiometric method with PL E-eye is portable, rapid, visible and highly selective especially in discriminate Cd2+ from Zn2+.
研究领域:
环境科学
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分析化学
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纳米技术
·
光学传感
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DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2020
·
IF 3.594
Na Zhang,Yujun Shen,Gaozong Pang,Suyun Chu,Wei Han,Qiong Mei,Xinlong Hu,Fengqi Dong,Yuxian Shen,Tingting Zhao
Owing to the great role of glucose in biological systems and food industry, it is significant to maintain the dynamic balance of organisms. Various methods widely reported are focused on the glucose detection with high sensitivity and low detection limit. However, the sensor with ultra-low concentration sensitivity is not suitable for the direct detection of high concentration of glucose in human serum and food samples. Additionally, the application of ratiometric fluorescence probe is usually limited by the narrow range of color changes and insensitivity color change of the target. Here, a novel dual-emission ratiometric fluorescence probe with green to red fluorescence intensity of 6:1 was first constructed by fluorescein isothiocyanate (FITC) with green fluorescence as signal unit and silica coated quantum dot (QD@SiO 2 ) with red fluorescence as the stable internal standard. The glucose was oxidized to generate H 2 O 2 by the catalysis of glucose oxidase , which can oxidize Fe 2+ to form Fe 3+ ion. The formation of Fe 3+ ion will cause the quenching of FITC fluorescence, which can realize the continuous fluorescence color change from green to yellow to orange to red for the qualitative and quantitative detection of blood glucose and fruit juice. The proposed method is cheap, simple, intuitive and has a wide detection range for glucose detection, which is of significance in designing the dual-emission ratiometric fluorescence sensor with wide range of color change.
研究领域:
分析化学
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生物化学
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纳米技术
·
传感器
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产品关联
DOI
高影响因子
ACS Biomaterials Science & Engineering
·
2017
·
IF 3.234
Hong-Yin Wang,Jie Sun,Liu-Yuan Xia,Yan-Hong Li,Zhan Chen,Fu-Gen Wu
Immunofluorescence staining is a crucial tool for studying the structure and behavior of intracellular proteins and organelles. During the staining process, the permeabilization treatment is usually required to enhance the penetration of a fluorescent antibody into the cells. However, since most of the membrane imaging dyes as well as the membrane lipids will detach from the cell surface after permeabilization, membrane labeling using these dyes is not compatible with immunofluorescence staining. Herein, by linking cholesterol-polyethylene glycol (PEG-Chol) and fluorescein isothiocyanate (FITC) with the amine-rich glycol chitosan (GC), we prepared a multifunctional polymeric construct, GC-PEG Chol-FITC, and realized permeabilization-tolerant plasma membrane imaging. Owing to the presence of abundant amine groups in the labeling reagent and the membrane proteins/lipids, the addition of paraformaldehyde in the fixation step induces the amine-cross-linking between the labeling reagents and the membrane proteins/lipids, thus preventing the detachment of fluorophores from the cell surface after permeabilization. Besides, the large molecular weight effect of the imaging reagent may also account for its antipermeabilization property. Furthermore, by combining immunofluorescence staining with the plasma membrane labeling by GC-PEG Chol-FITC, we simultaneously imaged the plasma membrane and cytoskeletons, and clearly observed metaphase cells and binucleated cells. The concept of using amine-rich polymeric dyes for plasma membrane imaging will inspire the development of more permeabilization-resistant membrane labeling dyes with better performance, which can realize simultaneous membrane and intracellular protein imaging and facilitate the future studies of membrane–intracellular protein interactions.
研究领域:
细胞生物学
·
材料科学
·
生物医学工程
·
分子生物学
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DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2017
·
IF 7.78
Shuzhen Yue,Tingting Zhao,Hongjie Qi,Yongcun Yan,Sai Bi
A toehold-mediated strand displacement (TMSD)-based cross-catalytic hairpin assembly (C-CHA) is demonstrated in this study, achieving exponential amplification of nucleic acids . Functionally, this system consists of four hairpins (H1, H2, H3 and H4) and one single-stranded initiator (I). Upon the introduction of I, the first CHA reaction (CHA1) is triggered, leading to the self-assembly of hybrid H1·H2 that then initiates the second CHA reaction (CHA2) to obtain the hybrid H3·H4. Since the single-stranded region in H3·H4 is identical to I, a new CHA1 is initiated, which thus achieves cross operation of CHA1 and CHA2 and exponential growth kinetics. Interestingly, because the C-CHA performs in a cascade manner, this system can be considered as multi-level molecular logic circuits with feedback mechanism. Moreover, through incorporating G-quadruplex subunits and fluorescein isothiocyanate (FITC) in the product of H1·H2, this C-CHA is readily utilized to fabricate a chemiluminescence resonance energy transfer (CRET) biosensing platform, achieving sensitive and selective detection of DNA and microRNA in real samples. Since the high background signal induced by FITC in the absence of initiator is greatly reduced through labeling quencher in H1, the signal-to-noise ratio and detection sensitivity are improved significantly. Therefore, our proposed C-CHA protocol holds a great potential for further applications in not only building complex autonomous systems but also the development of biosensing platforms and DNA nanotechnology.
研究领域:
分子生物学
·
生物化学
·
分析化学
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纳米技术
·
生物医学工程
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DOI
PubMed
高影响因子
Journal of Materials Chemistry B
·
2024
·
IF 6.1
Zhiheng Zhang,Hongchen Chen,Weize Diao,Chuangxin Zhou,Guozhen Liu
Eutectic gallium indium (EGaIn) nanoparticles can be modified with aniline derivatives to introduce versatile functional groups toward bioapplications beyond materials science. The p-aminobenzoic acid (PABA) modified EGaIn (EGaIn-PABA) demonstrated high wettability with the presence of carboxyl groups, but the priority of carboxyl and amino groups binding on EGaIn surface remains unclear. To study the binding nature of PABA to EGaIn, the anti-mouse IgG antibody labeled with fluorescein isothiocyanate (FITC) (IgG-FITC) was covalently modified to EGaIn-PABA to verify the presence of terminal carboxyl groups on EGaIn surface. The binding of gold nanoparticles (AuNPs) to EGaIn-PABA nanoparticles suggested the presence of terminal amino groups on EGaIn surface. Then, taking advantage of the reductive nature of amino groups, the Almar blue fluorescence experiment was designed to determine the co-existence of carboxyl and amino groups on the EGaIn-PABA surface with the approximate ratio of 3:7, suggesting carboxyl groups had a higher probability of binding with the EGaIn surface than that of amino groups. Then, an aptasensor was fabricated on the EGaIn-PABA surface with AuNPs for electrochemical detection of interleukin-6 with a sensitivity of 1 pg/mL.
研究领域:
材料科学
·
生物传感器
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纳米技术
·
分析化学
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生物医学工程
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产品关联
DOI
PubMed
高影响因子
Food & Function
·
2024
·
IF 5.1
Zhengming Xu,Kseniya Hileuskaya,Aliaksandr Kraskouski,Yujiao Yang,Zhe Huang,Zhengang Zhao
A diet containing natural active compounds that can inhibit the hydrolytic activity of α-glucosidase on carbohydrates and intestinal glucose absorption is an effective means of controlling postprandial hyperglycemia. Phlorizin and polydatin as phenolic glycosides had a high affinity to the catalytic site of α-glucosidase, but exhibited unsatisfactory competitive inhibitory capacity, with IC50 of 0.97 and > 2 mM, respectively. However, dodecyl-acylated derivatives of phlorizin and polydatin exerted α-glucosidase inhibitory capacity, with IC50 of 55.10 and 70.95 µM, respectively, which were greatly enhanced and much stronger than that of acarbose with IC50 of 2.46 mM. Both dodecyl phlorizin and dodecyl polydatin reduced the catalytic ability of α-glucosidase by reversible noncompetitive and uncompetitive mixed inhibition, which bind noncovalently to the allosteric site 2 through hydrogen bonds and hydrophobic interactions, thereby inducing the secondary structure unfolding and intrinsic fluorescence quenching of α-glucosidase. Confocal microscopy detection visually showed the significant inhibitory effects on FITC-labeled glucose uptake in intestinal Caco-2 cells by phlorizin, polydatin, dodecyl phlorizin and dodecyl polydatin. In addition, based on the differentiated Caco-2 cell monolayer model, dodecyl phlorizin and dodecyl polydatin suppressed intestinal glucose transport more effectively than phlorizin and polydatin, suggesting that they were promising in vivo hypoglycemic active compounds.
研究领域:
药理学
·
生物化学
·
分子生物学
·
营养学
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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）