A novel competitive aptasensor for thrombin detection is developed by using a tetrahedral DNA (T-DNA) probe and hybridization chain reaction (HCR) signal amplification. Sulfur and nitrogen co-doped reduced graphene oxide (SN-rGO) is firstly prepared by a simple reflux method and used for supporting substrate of biosensor. Then, T-DNA probe is modified on the electrode by Au-S bond and a competition is happened between target thrombin and the complementary DNA (cDNA) of aptamer. The aptamer binding to thrombin forms an aptamer-target conjugate and make the cDNA remained, and subsequently hybridizes with the vertical domain of T-DNA. Finally, the cDNAs trigger HCR, which results in a great current response by the catalysis of horseradish peroxidase to the hydrogen peroxide + hydroquinone system. For thrombin detection, the proposed biosensor shows a wide linearity range of 10-10M and a low detection limit of 11.6fM (S/N = 3), which is hopeful to apply in biotechnology and clinical diagnosis.
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http://dx.doi.org/10.1016/j.bios.2017.09.022 | DOI Listing |
Biomaterials
January 2025
Tianjin Key Laboratory of Function and Application of Biological Macromolecular Structures, School of Life Sciences, Faculty of Medicine, Tianjin University, Tianjin, 300072, China. Electronic address:
As a promising anti-tumor modality, photodynamic immunotherapy (PDIT) has been applied for the treatment of many solid tumors. However, tumor hypoxic condition and immunosuppressive microenvironment severely limit the treatment outcome of PDIT. Here, we have designed a hairpin tetrahedral DNA nanostructure (H-TDN)-modified bifunctional cascaded Pt single-atom nanozyme (PCFP@H-TDN) with encapsulation of the photosensitizer.
View Article and Find Full Text PDFTalanta
January 2025
School of Life Science, Jiangsu Normal University, Xuzhou, 221116, China.
Sensitive and accurate detection and imaging of different microRNAs (miRNAs) in cancer cells hold great promise for early disease diagnosis. Herein, a DNA tetrahedral scaffold (DTS)-corbelled autonomous-motion (AM) molecular machine based fluorescent sensing platform was designed for simultaneous detection of two types of miRNAs (miRNA-21 and miRNA-155) in HeLa cells. Locking-strand-silenced DNAzymes (P:L duplex) were firstly grafted at the loop of target-analogue-embedded double-stem hairpin substrates (TDHS) of DTS, making the sensor in a "signal off" state due to the closely distance between modified fluorophores (FAM and Cy5) with the corresponding quenchers (BHQ1 and BHQ2).
View Article and Find Full Text PDFAnal Chem
January 2025
Key Laboratory of Laboratory Medicine, Ministry of Education of China, and Zhejiang Provincial Key Laboratory of Medical Genetics, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou 325035, China.
An RCA product is a promising scaffold for the construction of DNA nanostructures, but so far, there is no RCA scaffold-based dynamic reconfigurable nanorobot for biological applications. In this contribution, we develop an intracellular stimuli-responsive reconfigurable coiled DNA nanosnake (N-Snake) by using incomplete aptamer-functionalized (A) DNA tetrahedrons (T) to fold a long tandemly repetitive DNA strand synthesized by rolling circle amplification reaction (R) with the help of palindromic fragment (P). A DNA-assembled product, ARTP, including spiked aptamers, can retain the structural integrity even if exposed to fetal bovine serum (FBS) for 24 h and displays substantially enhanced target molecule-dependent cellular internalization efficiency.
View Article and Find Full Text PDFMikrochim Acta
January 2025
College of Chemistry and Environmental Engineering, Sichuan University of Science and Engineering, Zigong, 643000, P.R. China.
Cytosine-rich and poly(adenine)-tailed tetrahedral DNA framework (TDF) is designed as template (A-TDF) for anchoring silver nanoclusters (AgNCs) and igniting the dual-color fluorescence of AgNCs. The resultant DNA-AgNCs simultaneously emits red and green fluorescence, and the quantum yield of red fluorescence is as high as 44.8%.
View Article and Find Full Text PDFNanoscale
January 2025
State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, Sichuan, China.
Rheumatoid arthritis (RA) remains a challenging autoimmune disease due to its complex and heterogeneous pathophysiology, which complicates therapeutic and diagnostic efforts. Advances in DNA nanotechnology have introduced DNA nanomaterials as promising tools to overcome these barriers. This review focuses on three primary categories of DNA nanomaterials applied in RA: DNA nanostructures, DNA aptamers, and DNA-modified nanoparticles.
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