共查询到19条相似文献,搜索用时 78 毫秒
1.
具有特定构象的富G序列(如G-四链体和G-三链体)与荧光染料相互作用可有效增强其荧光信号强度,被广泛应用于构建无标记荧光生物传感。本研究以硫磺素T(Thioflavin T, ThT)为荧光染料,构建了两种基于富G序列的无标记荧光传感器,用于检测阿尔兹海默病标志物β-淀粉样蛋白(β-Amyloid protein, Aβ)的基因序列。实验结果表明,分子发夹茎长为4个碱基时,富G序列以G-三链体的结构存在,以此构建的G-三链体传感器的输出信号随Aβ基因浓度增加而降低,线性检测范围为1~100 nmol/L,检出限为0.3 nmol/L(S/N=3)。分子发夹茎长为8个碱基且5′端添加碱基AATT时,其与Aβ基因结合后,富G序列多以G-四链体结构存在,以此构建的G-四链体传感器的输出信号随Aβ基因浓度增加而增强,线性检测范围为0.1~100 nmol/L,检出限为0.04 nmol/L (S/N=3)。两种传感器制备过程相似但检测原理不同,为富G序列的深入研究与应用提供了参考,同时为单链核酸的无标记荧光检测提供了新的思路。 相似文献
2.
3.
4.
5.
6.
肿瘤已成为严重威胁人类健康的重大疾病之一。以顺铂为首的铂类抗肿瘤药物一直是化疗首选药物。但是长期用药导致的一系列的毒副作用如肾毒性、耳毒性和耐药性等极大地限制了铂类配合物的发展与应用。本文针对目前铂类药物所处形势重点综述了新一代铂类药物的设计研发方法:(1)研发具有新颖结构的铂类药物,例如经过改造的反式铂类配合物、多核铂类配合物、Pt(Ⅳ)配合物等;(2)发展新的抗肿瘤靶点,例如以G-四螺旋DNA(G4-DNA)为靶点,为寻找更有效的铂类抗肿瘤药物提供新的思路。同时通过列举最新研究成果,分析药物的抗肿瘤机理及在克服顺铂耐药性机理方面的研究进展,提出铂类药物的设计研发方法,让读者了解铂类抗肿瘤药物的发展历程和未来的发展趋势。 相似文献
7.
8.
富含鸟嘌呤的DNA或RNA序列可以折叠成非典型G-四链体二级结构. G-四链体结构丰富多样,在生物体内动态存在,参与了转录、复制、基因组稳定性和表观遗传调控等关键的基因组功能,与癌症生物学密切相关. G-四链体的结构与功能机制研究促进了以G-四链体为靶点的肿瘤治疗干预.本文综合评述了核酸G-四链体的特异性识别、细胞内探测及生物学功能的调控,总结了识别靶向G-四链体的小分子及复合物结构的研究进展,讨论了以G-四链体为靶点的靶向干预及疾病治疗的可能性,最后展望了G-四链体未来研究所面临的挑战与机遇. 相似文献
9.
富含鸟嘌呤碱基的DNA序列能够通过鸟嘌呤环的互联作用形成四链螺旋结构,这种结构被称为G-四链体。G-四链体由于能够抑制端粒酶的活性而成为抗肿瘤药物的新靶点,能促使G-四链体形成或稳定该结构的物质则可能对癌症有潜在的治疗意义。本文对以G-四链体为靶点的小分子端粒酶抑制剂的研究进行了综述。 相似文献
10.
11.
Koval O. A. Chernolovskaya E. L. Litvak V. V. Vlassov V. V. 《Russian Chemical Bulletin》2003,52(11):2517-2522
Site-directed cleavage of single- and double-stranded DNAs by an oligonucleotide conjugate with 5-[N-(3-aminopropyl)sulfamoyl]-2-bromobenzoic acid was investigated. When forming duplex complexes with a single-stranded DNA and triplex complexes with a double-stranded DNA, this conjugate cleaves DNA near the binding site in the presence of copper ions and free o-bromobenzoic acid. The efficacy and specificity of DNA cleavage by this conjugate and other oligonucleotide conjugates bearing tetracarboxyphthalocyanine CoII and bleomycin A5 as reactive groups were compared. 相似文献
12.
An autonomous DNA nanomachine based on rolling circle amplification (RCA)-bridged two-stage exonuclease III (Exo III)-induced recycling amplification (Exo III-RCA-Exo III) was developed for label-free and highly sensitive homogeneous multi-amplified detection of DNA combined with sensitive fluorescence detection technique. According to the configuration, the analysis of DNA is accomplished by recognizing the target to a unlabeled molecular beacon (UMB) that integrates target-binding and signal transducer within one multifunctional design, followed by the target-binding of UMB in duplex DNA removed stepwise by Exo III accompanied by the releasing of target DNA for the successive hybridization and cleavage process and autonomous generation of the primer that initiate RCA process with a rational designed padlock DNA. The RCA products containing thousands of repeated catalytic sequences catalytically hybridize with a hairpin reporter probe that includes a “caged” inactive G-quadruplex sequence (HGP) and were then detected by Exo III-assisted recycling amplification, liberating the active G-quadruplex and generating remarkable ZnPPIX/G-quadruplex fluorescence signals with the help of zinc(II)-protoporphyrin IX (ZnPPIX). The proposed strategy showed a wide dynamic range over 7 orders of magnitude with a low limit of detection of 0.51 aM. In addition, this designed protocol can discriminate mismatched DNA from perfectly matched target DNA, and holds a great potential for early diagnosis in gene-related diseases. 相似文献
13.
Xue-Wen Liu Ning-Yi Liu Yuan-Qing Deng Shan Wang Ting Liu Yu-Cai Tang Yuan-Dao Chen Ji-Lin Lu 《应用有机金属化学》2020,34(8):e5703
The detection of G-quadruplex is of major interest. Nitro-substituted ruthenium (II) complexes have attracted much attention due to fluorescent sensitivity to environment change. We report here a new nitro-substituted ruthenium (II) complex, [Ru (phen)2(hnoip)]2+ ( 1) (hnoip = 2-(2-hydroxyl-5-nitrophenyl)imidazo[4,5-f][1,10-phenanthroline]), which displays distinct fluorescent properties in aqueous solution and non-aqueous solvents. This complex exhibits large fluorescence enhancement after binding with G-quadruplex DNA, and displays good fluorescent selectivity over other DNAs. The limit of detection is 6 nm for 22AG in Na+ and 43 nm for 22AG in K+, respectively. The results demonstrated that nitro-substituted ruthenium (II) complexes can be utilized to design as G-quadruplex fluorescent probes by protection of the nitro group on the complex from water. 相似文献
14.
水的氧化是光合作用的重要步骤,其提供用于二氧化碳固定的电子和质子,以及生物圈所必需的氧气.在将太阳能转换为化学能的人工光合作用中,设计合成高效稳定的水氧化催化剂是研究的关键.目前的催化体系主要是基于钌和铱等贵金属的金属氧化物纳米颗粒和多核金属配合物.基于钌和铱的单核催化体系近年来也得到了广泛的发展.最近几年,第一过渡系列金属元素单核水氧化催化剂快速得到重视.作为配合物中心原子,它们不仅具有丰富的氧化态,而且因相对充足的蕴藏和较低的开采冶炼成本,其具有钌和铱等贵金属不可比拟的重大优势和广阔的应用前景.本文总结了近几年第一过渡系列金属元素单核水氧化催化剂的进展,并在此基础上,简单讨论了氧—氧键的生成,为进一步设计新颖、具有高催化效率和高稳定性的单核水氧化催化剂提供了理论依据. 相似文献
15.
A novel nanoparticle-bioconjugate has been prepared by specific hybridization of the target with complementary thiol-labeled and nanoparticle-labeled probes. The rapid adsorption of the nanoparticle-bioconjugate onto a gold surface via a thiol-gold reaction was monitored in real-time using a quartz crystal microbalance, and used to perform microgravimetric flow analysis of nucleic acid for the first time. This innovative assay is highly reproducible and sensitive, and shows great promise for clinical applications. 相似文献
16.
Determination of nucleic acid based on increased resonance light-scattering of fluorinated surfactants 总被引:1,自引:0,他引:1
Ling Li 《Journal of fluorine chemistry》2009,130(6):567-728
Two novel surfactants perfluoroalkanesulfonyl quaternary ammonium iodides (FC134) and potassium perfluorooctanesulfonate (FC95) were successfully used as new probes for detection of DNA by resonance light-scattering (RLS) technique. Resonance light-scattering characteristics of the binding of fluorinated surfactants FC134 and FC95 to calf thymus nucleic acid (ctDNA) were studied. After DNA was added, aggregation of FC134 on the molecular surface of DNA in the pH 3.0-6.0 and aggregation of FC95 on the surface of DNA in the pH 3.5-6.0 occurred, both of which resulted in an enhanced resonance light-scattering peak at 370 nm. The intensity of resonance light-scattering was found to be proportional to the concentration of DNA. The determination limits were 3.5 and 20.0 μg L−1, respectively. UV-vis spectra and IR-spectra both proved the binding of fluorinated surfactants to DNA. 相似文献
17.
We report a novel label-free method for the investigation of the adaptive recognition of small molecules by nucleic acid aptamers using capillary electrophoresis analysis. Cocaine and argininamide were chosen as model molecules, and the two corresponding DNA aptamers were used. These single-strand DNAs folded into their specific secondary structures, which were mainly responsible for the binding of the target molecules with high affinity and specificity. For molecular recognition, the nucleic acid structures then underwent additional conformational changes, while keeping the target molecules stabilized by intermolecular hydrogen bonds. The intrinsic chemical and physical properties of the target molecules enabled them to act as indicators for adaptive binding. Thus any labeling or modification of the aptamers or target molecules were made obsolete. This label-free method for aptamer-based molecular recognition was also successfully applied to biological fluids and therefore indicates that this approach is a promising tool for bioanalysis. 相似文献
18.
19.
Hao Yue Wan Chan KongJie Yu Lin Guo Ning Liu HuWei Liu ZongWei Cai 《中国科学B辑(英文版)》2009,52(10):1576-1582
Aristolochic acid (AA), a mixture of structure-related nitrophenanthrene carboxylic acid derivatives derived from Aristolochia spp, is associated with nephrotoxin and carcinogen. AA-DNA adducts induced by reductive metabolic activation of AA were detected in tissues of animals and in patients exposed to AA. The DNA adducts were generally used as biomarkers in toxicological study of AA. In this short review, quantitative analysis of AA-DNA adducts in various in vitro and in vivo systems by using 32P-postlabe... 相似文献