TALANTA
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2016
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IF 4.035
Bei Hua Kang,Zhong Feng Gao,Na Li,Yan Shi,Nian Bing Li,Hong Qun Luo
Silver ions have been widely applied to many fields and have harmful effects on environments and human health. Herein, a label-free optical sensor for Ag + detection is constructed based on thiazole orange (TO) as a fluorescent probe for the recognition of i-motif DNA structure change at neutral pH. Ag + can fold a C-rich single stranded DNA sequence into i-motif DNA structure at neutral pH and that folding is reversible by chelation with cysteine (Cys). The DNA folding process can be indicated by the fluorescence change of TO, which is non-fluorescent in free molecule state and emits strong fluorescence after the incorporation with i-motif DNA. Thus, a rapid, sensitive, and selective method for the detection of Ag + and Cys is developed with a detection limit of 17 and 280 nM, respectively. It is worth noting that the mechanism underlying the increase of the fluorescence of thiazole orange in the presence of i-motif structure is explained. Moreover, a fluorescent DNA logic gate is successfully designed based on the Ag + /Cys-mediated reversible fluorescence changes. The proposed detection strategy is label-free and economical. In addition, this system shows a great promise for i-motif/TO complex to analyze Ag + in the real samples.
研究领域:
分析化学
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生物化学
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分子生物学
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环境科学
✓ 已验证
DOI
PubMed
高影响因子
MOLECULAR PHARMACEUTICS
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2020
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IF 4.321
Dandan Miao,Yanyan Yu,Yong Chen,Yin Liu,Gaoxing Su
Stimuli-responsive DNA-based nanostructures have emerged as promising vehicles for intelligent drug delivery. In this study, i-motif DNA-conjugated gold nanostars (GNSs) were fabricated in a facile manner as stimuli-responsive drug delivery systems (denoted as A-GNS/DNA/DOX) for the treatment of cancer via combined chemo-photothermal therapy. The i-motif DNA is sensitive to the environmental pH and can switch from a single-stranded structure to a C-tetrad (i-motif) structure as the environmental pH decreases from neutral (∼7.4) to acidic (<6.0). The loaded drug can then be released along with the conformational changes. To enhance cellular uptake and improve cancer cell selectivity, the aptamer AS1411, which recognizes nucleolins, was employed as a targeting moiety. The A-GNS/DNA/DOX nanocomposites were found to be highly capable of photothermal conversion and exhibited photostability under near-infrared (NIR) irradiation, and the pH and NIR irradiation effectively triggered the drug-release behaviors. In addition, the A-GNS/DNA/DOX nanocomposites exhibited good biocompatibility. The targeting recognition enabled the A-GNS/DNA/DOX to exhibit higher cellular uptake and therapeutic efficiency than the GNS/DNA/DOX. Notably, under NIR irradiation, a synergistic effect between chemotherapy and photothermal therapy can be achieved with the proposed delivery system, which exhibits much higher therapeutic efficiency both in monolayer cancer cells and tumor spheroids as compared with a single therapeutic method. This study highlights the potential of GNS/DNA nanoassemblies for intelligent anticancer drug delivery and combined cancer therapy.
研究领域:
纳米技术
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癌症研究
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药物递送系统
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生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Sensors
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2020
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IF 7.333
Dandan Zhao,Haoran Tang,Hao Wang,Cheng Yang,Yongxin Li
The nanopore-based technique is a useful tool for single-molecule sensing and characterization. In this work, we have developed a new DNA-functionalized gold-modified nanopore, and analytes can induce the conformational switch of i-motif DNA formed on the inner surface of the nanopore. i-Motif DNA structure can be formed in the presence of silver ions (Ag+), which will result in the change in surface charge and structure of the nanopore tip and ion current rectification (ICR) ratio. The i-motif DNA structure on nanopore surface will be destroyed after the addition of glutathione (GSH) due to the strong interaction of Ag–S bond, which results in the recovery of surface charge, steric hindrance, and ICR ratio. This analyte-triggered conformational switch of i-motif DNA can help us deeply understand the DNA technology inside single nanopore and will benefit the possible applications in an ultrasensitive detection and biological/chemical analysis.
研究领域:
纳米技术
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生物物理学
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分子生物学
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Acta Biomaterialia
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2024
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IF 9.4
Kunlin Li,Lin Li,Xiyue Xie,Jing Zhu,Daqing Xia,Lunli Xiang,Kaiyong Cai,Jixi Zhang
Although immunogenic cell death (ICD) induced by lysosomal membrane permeabilization (LMP) evidently enhance the effectiveness of antitumor immunity for triple-negative breast cancer (TNBC) with poor immunogenicity, their potential is increasingly restricted by the development of other death pathways and the repair of lysosomes by endoplasmic reticulum (ER) during LMP induction. Herein, a polydopamine nanocomposite with i-motif DNA modified and BNN6 loaded is prepared toward boosting LMP and immunotherapy of TNBC by synergy of spatially confined photoacoustic (PA) effects and nitric oxide. Combining the high-frequency pulsed laser (4000 kHz) with the intra-lysosomal assembly of nanocomposites produced spatially confined and significantly boosted PA effects (4.8-fold higher than the individually dispersed particles extracellular), suppressing damage to other cellular components and selectively reducing lysosomal integrity to 19.2%. Simultaneously, the releasing of nitric oxide inhibited the repair of lysosomes by ER stress, causing exacerbated LMP. Consequently, efficient immune activation was achieved, including the abundant releasing of CRT/HMGB1 (5.93–6.8-fold), the increasing maturation of dendritic cells (3.41-fold), and the fostered recruitment of CD4 + /CD8 + T cells (3.99–3.78-fold) in vivo. The study paves a new avenue for the rational design and synergy of confined energy conversion and responsive nanostructures to achieve the treatment of low immunogenicity tumors. Statement of Significance A strategy of boosting lysosomal membrane permeabilization (LMP) and concomitantly preventing the repair was developed to address the immunotherapy challenge of triple-negative breast cancer. Spatially confined and significantly enhanced photoacoustic (PA) effects were achieved through DNA-guided pH-responsive assembly of polydopamine nanocomposites in lysosomes and application of a high-frequency pulsed laser. Efficient immunogenic cell death was guaranteed by selective and powerful damage of lysosomal membranes through the significant contrast of PA intensities for dispersed/assembled particles and nitric oxide release induced endoplasmic reticulum stress. The study paves a new avenue for the rational design and synergy of confined energy conversion and responsive nanostructures to achieve the treatment of low immunogenicity tumors.
研究领域:
癌症生物学
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纳米技术
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免疫治疗
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生物医学工程
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光声成像
✓ 已验证
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）