Demantkryger8200

A strategy based on fluorescence coupled capillary electrophoresis (CE-FL) was developed for analyzing tetrahedron DNA (TD) and TD-doxorubicin (DOX) conjugate. Capillary gel electrophoresis exhibited desirable performance for separating TD and DNA strands. Under the optimized conditions, satisfactory repeatability concerning run-to-run and interday repeatability was obtained, and relative standard deviation value of resolution (n = 6) was 0.64%. Furthermore, the combination of CE and fluorescence detection provided a sensitive platform for quantifying TD concentration and calculating the damage degree of TD. The electrophoretograms indicated that CE-FL was a suitable TD assay method with high specificity and sensitivity. In addition, the application of CE-FL for TD fluorescence resonance energy transfer (FRET) research was also explored. Two types of DNA strands were utilized to interfere the formation of TD. The impact of partially complementary chain and completely complementary chain on FRET signal was explored, and the influence mechanism was discussed. After applying CE-FL for characterizing TD, we also combine CE and FRET to analyze TD-DOX conjugate. CE presented a favourable technique to monitor DOX loading and releasing processes. These noteworthy results offered a stepping stone for DNA nanomaterials assay by using CE-FL.Carbon nanodots (CNDs) have been widely applied in variety of fields, while some evidences indicate their components may be complicated. In this work, capillary electrophoresis (CE) was used to evaluate the effect of synthetic conditions of fluorescent CNDs prepared through the hydrothermal method using citric acid (CA) and Triaminoguanidinium chloride (TGCl) as the starting materials. The results indicated that the fluorescent components of the products were affected by the ratio of the starting materials, the reaction temperature and reaction time. Under selected conditions, a ratio of TGCl to CA of 16, the reaction at 180 °C for 3 h, the product contains more than 4 fluorescent components with similar optical properties. CNDs were used for the determination of Cr(VI) in environmental samples with recoveries ranging in 95.3-107%, and the mechanism was also confirmed.Alkaline phosphatase (ALP), as an immunological label, is widely used in biochemical assays. Here, a simple yet effective strategy for ALP activity detection was proposed on the basis of in situ formation of Prussian blue nanoparticles and polychromatic superposition effect. Firstly, ascorbic acid, a product from ALP-catalyzed hydrolysis of 2-phospho-l-ascorbic acid (AAP), converted yellow ferricyanide into ferrocyanide. Then, the specific reaction between ferrocyanide and ferric ions (Fe3+) initiated the generation of Prussian blue nanoparticles in situ. Meanwhile, the residual AAP chelated with Fe3+, and a stable Fe3+-AAP complex was quickly formed. When Prussian blue nanoparticles mixed with brown Fe3+-AAP complex and yellow ferricyanide at different ratios, a distinct color variation was presented. Therefore, a sensitive multicolor assay of ALP activity with a detection limit of 1.0 U/L was realized by simply blending commercially available reagents. Furthermore, magnetic sandwich and competitive sensing platforms for multiple biomarkers detection were constructed by combining the ALP-regulated multicolor system with the well-developed aptasensor. The feasibility of the sensors was convincingly demonstrated by using thrombin and prostate specific antigen as model targets. In addition, the proposed multicolor strategy was employed for evaluating inhibition efficiency, and shows potential in visual screening of enzyme inhibitors. Such a facile, sensitive and low-cost sensing strategy provides a new perspective to develop universal platforms of point-of-care testing.In this research, a novel Ag3PO4 NPs@MoS2 nanosheet-based electrochemiluminescence (ECL) sensing system was developed to provide an effective method for tumor gene detection. Tamoxifen solubility dmso At first, fluorine, sulfur-doped BN quantum dot (F, S-BN QD) were prepared as ECL emitter. Sulfur dopant can provide more reactive sites in the ECL reaction. Fluorine atoms in the QD structure further improved the stability of the crystal. Furthermore, Ag3PO4 NP@MoS2 nanosheets were fabricated via a hydrothermal route as ECL reaction catalyst. On the one hand, Ag3PO4 NP@MoS2 nanosheets promoted the generation of more oxidant of coreactant in the F, S-BN QD/H2O2 coreactant ECL pathway. On the other hand, the excellent conductivity of Ag3PO4 NP@MoS2 nanosheets facilitated the electron transfer and effectively reduce the damage of F, S-BN QD by excessive hot electrons. Finally, the proposed biosensor was designed to accurately quantify K-ras tumor gene from 10 fM to 100 pM with a limit of detection (LOD) of 0.2 fM. The sensing system was used to detect K-ras gene in human colorectal cancer tumor and tumor-adjacent tissues samples with satisfactory results. The amplified ECL sensing strategy with Ag3PO4 NPs@MoS2 nanosheet has significant potential value in the clinical detection.Tumor is a kind of abnormal organism generated by the proliferation and differentiation of cells in the body under the action of various initiating and promoting factors, which seriously threatens human life and health. Tumorigenesis is a gradual process that involves multistage reactions and the accumulation of mutations. Gene mutation usually occurs during tumorigenesis, and can be used for tumor diagnosis. Early diagnosis is the most effective way to improve the cure rate and reduce the mortality rate. Among the peripheral blood circulating tumor DNA (ctDNA), gene mutation in keeping with tumor cells can be detected, which can potentially replace tumor tissue section for early diagnosis. It has been considered as a liquid biopsy marker with good clinical application prospect. However, the high fragmentation and low concentration of ctDNA in blood result in the difficulty of tumor stage determination. Therefore, high sensitive and specific mutation detection methods have been developed to detect trace mutant ctDNA. At present, the approaches include digital PCR (dPCR), Bead, Emulsion, Amplification and Magnetic (BEAMing), Next Generation Sequencing (NGS), Amplification Refractory Mutation System (ARMS), etc. In this paper, the principle, characteristics, latest progress and application prospects of these methods are reviewed, which will facilitate researchers to choose appropriate ctDNA detection approaches.