Graphene oxide (GO) has unique structural properties, can effectively adsorb single-strand DNA through π–π stacking, hydrogen bonding and hydrophobic interactions, and is useful in many biotechnology applications. In this study, we developed a thrombin-binding-aptamers (15- and 29-mer) conjugated graphene oxide (TBA₁₅/TBA₂₉–GO) composite for the efficient inhibition of thrombin activity towards the formation of fibrin from fibrinogen. The TBA₁₅/TBA₂₉–GO composite was simply obtained by the self-assembly of TBA₁₅/TBA₂₉ hybrids on GO. The high density and appropriate orientation of TBA₁₅/TBA₂₉ on the GO surface enabled TBA₁₅/TBA₂₉–GO to acquire an ultrastrong binding affinity for thrombin (dissociation constant = 2.9 × 10⁻¹² M). Compared to bivalent TBA₁₅h₂₀A₂₀/TBA₂₉h₂₀A₂₀ hybrids, the TBA₁₅/TBA₂₉–GO composite exhibited a superior anticoagulant potency (ca. 10-fold) against thrombin-mediated coagulation as a result of steric blocking effects and a higher binding affinity for thrombin. In addition, the prolonged thrombin clotting time, prothrombin time (PT), and activated partial thromboplastin time (aPTT) of TBA₁₅/TBA₂₉–GO were at least 2 times longer than those of commercially available drugs (heparin, argatroban, hirudin, and warfarin). The in vitro cytotoxicity and hemolysis analyses revealed the high biocompatibility of TBA₁₅/TBA₂₉–GO. The rat-tail bleeding assay of the hemostasis time and ex vivo PT and aPTT further revealed that TBA₁₅/TBA₂₉–GO is superior (>2-fold) to heparin, which is commonly used in the treatment and prevention of thrombotic diseases. Our multivalent, oligonucleotide-modified GO nanocomposites are easy to prepare, cost-effective, and highly biocompatible and they show great potential as effective anticoagulants for the treatment of thrombotic disorders.

中文翻译：

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在氧化石墨烯上自组装的二价适体作为有效的抗凝剂†

氧化石墨烯（GO）具有独特的结构特性，可以通过π-π堆积，氢键和疏水相互作用有效吸附单链DNA，并在许多生物技术应用中有用。在这项研究中，我们开发了一种凝血酶结合适体（15和29个单体）共轭氧化石墨烯（TBA ₁₅ / TBA ₂₉ –GO）复合材料，可有效抑制凝血酶对纤维蛋白原从纤维蛋白原形成的活性。通过在GO上自组装TBA ₁₅ / TBA ₂₉杂种，可以简单地获得TBA ₁₅ / TBA ₂₉ -GO复合材料。TBA ₁₅ / TBA ₂₉在GO表面上的高密度和适当的定向使TBA成为可能₁₅ / TBA ₂₉ –GO获得对凝血酶的超强结合亲和力（解离常数= 2.9×10 ^-12 M）。与二价TBA ₁₅ h ₂₀ A ₂₀ / TBA ₂₉ h ₂₀ A ₂₀杂种相比，TBA ₁₅ / TBA ₂₉ -GO复合材料由于空间阻滞，对凝血酶介导的凝血显示出优异的抗凝效力（约10倍）效果和对凝血酶的更高结合亲和力。此外，TBA ₁₅ / TBA ₂₉延长的凝血酶凝血时间，凝血酶原时间（PT）和活化的部分凝血活酶时间（aPTT）–GO至少比市售药物（肝素，阿加曲班，水rud素和华法林）长2倍。在体外细胞毒性和溶血分析揭示TBA的高生物相容性₁₅ / TBA ₂₉ -GO。对止血时间和离体PT和aPTT的尾巴出血分析进一步表明，TBA ₁₅ / TBA ₂₉ -GO优于（大于2倍）肝素，后者通常用于治疗和预防血栓性疾病。我们的多价，寡核苷酸修饰的GO纳米复合材料易于制备，具有成本效益且具有高度生物相容性，并且作为治疗血栓性疾病的有效抗凝剂具有巨大潜力。