Krarup Anthony (artactive5)

DNA glycosylase is an indispensable DNA damage repair enzyme which can recognize and excise the damaged bases in the DNA base excision-repair pathway. The dysregulation of DNA glycosylase activity will give rise to the dysfunction of base excision-repair and lead to abnormalities and diseases. The simultaneous detection of multiple DNA glycosylases can help to fully understand the normal physiological functions of cells, and determine whether the cells are abnormal in pre-disease. Regrettably, the synchronous detection of functionally similar DNA glycosylases is a great challenge. Herein, we developed a multifunctional dsDNA probe mediated exponential rolling circle amplification (E-RCA) method for the simultaneously sensitive detection of human alkyladenine DNA glycosylase (hAAG) and uracil-DNA glycosylase (UDG). Rucaparib The multifunctional dsDNA probe contains the hypoxanthine sites and the uracil sites which can be recognized by hAAG and UDG respectively to generate apyrimidinic (AP) sites in the dsDNA probe. Then the AP sites will be recognized and cut by endonuclease Ⅳ (Endo IV) to release corresponding single-stranded primer probes. Subsequently, two padlock DNA templates are added to initiate E-RCA to generate multitudinous G-quadruplexes and/or double-stranded dumbbell lock structures, which can combine N-methyl mesoporphyrin IX (NMM) and SYBR Green Ⅰ (SGI) for the generation of respective fluorescent signals. The detection limits are obtained as low as 0.0002 U mL-1 and 0.00001 U mL-1 for hAAG and UDG, respectively. Notably, this method can realize the simultaneous detection of two DNA glycosylases without the use of specially labeled probes. Finally, this method is successfully applied to detect hAAG and UDG activities in the lysates of HeLa cells and Endo1617 cells at single-cell level, and to detect the inhibitors of DNA glycosylases.In this work, a catalytic material of cobalt doped nitrogenous porous carbon (Co/NPC) was fabricated from covalent organic frameworks (COFs) and cobalt ion via directly carbonization. Attribute to the excellent selective catalytic performance towards n-hexane, Co/NPC was employed in cataluminescence (CTL) for rapid and sensitive determination of n-hexane. Moreover, the detection conditions of CTL were evaluated, including temperature, flow rate and detecting wavelength. Under optimized conditions, a good linear relation between signal intensity of CTL and n-hexane concentration was obtained in the linear range of 0.4-250.0 mg/L and the limit of detection (LOD, S/N = 3) was 0.13 mg/L. Furthermore, the Co/NPC based CTL sensor was successfully applied to the determination of n-hexane in edible oil samples with the recoveries in the range of 92.0%-104.0%. The method comparison results of GC/MS and CTL on real sample analysis further proved the accuracy of the developed Co/NPC based CTL method. Additionally, the possible catalytic mechanism of n-hexane on the surface of Co/NPC was investigated, assisting by GC/MS on intermediation products identification. Overall, the Co/NPC based CTL sensor has been confirmed excellent performance in the n-hexane determination, which revealing extensive application in rapid residual n-hexane analysis in edible oil.The continuous intake of 17β-estradiol (E2) residue from animal-derived food may pose a threat to the health of consumers, so the rapid screen and detection of E2 is very necessary. Although visual immunochromatographic strip (ICS) has played a great role in food safety control such as the screen of many food contaminants, it cannot meet the requirements for E2 detection due to the insufficient sensitivity of traditional visual ICS and the low concentration range of estrogen in food. Here, we developed a dual-mode ICS strategy to achieve rapid and highly sensitive detection of E2. Based on the visual detection mode of a competitive ICS, the afterglow detection mode working in fluorescence resonance energy transfer mechanism was introduced b