A “signal-on” chemiluminescence biosensor for thrombin detection based on DNA functionalized magnetic sodium alginate hydrogel and metalloporphyrinic metal-organic framework nanosheets

• Published in: Talanta (Oxford) 2020-01, Vol.207, p.120300-120300, Article 120300
• Main Authors: Lin, Yanna, Sun, Yuanling, Dai, Yuxue, Sun, Weiyan, Zhu, Xiaodong, Liu, Hao, Han, Rui, Gao, Dandan, Luo, Chuannan, Wang, Xueying
• Format: Article
• Language: English
• Subjects: Adsorption; Alginates - chemistry; Aptamer; Aptamers, Nucleotide - chemistry; Aptamers, Nucleotide - genetics; Aptamers, Nucleotide - metabolism; Base Sequence; Biosensing Techniques - methods; DNA, Single-Stranded - chemistry; DNA, Single-Stranded - genetics; Flow injection chemiluminescence; Hydrogels - chemistry; Luminescent Measurements; Magnets - chemistry; Metal-Organic Frameworks - chemistry; Metalloporphyrinic metal-organic framework nanosheets; Models, Molecular; Molecular Conformation; Nanotubes, Carbon - chemistry; Porphyrins - chemistry; Sodium alginate hydrogel; Thrombin; Thrombin - analysis; Thrombin - metabolism
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2019.120300

A “signal-on” chemiluminescence biosensor was established for detecting thrombin. The thrombin aptamer1-functionalized magnetic sodium alginate (Malg-Apt1) hydrogel was synthesized by physical interaction between sodium alginate and Ca2+, and it was used in the biosensor for separating and enriching thrombin. Ethylenediamine tetraacetic acid (EDTA) was used to chelate with Ca2+ to dissolve the hydrogel and release thrombin. A metalloporphyrinic metal-organic framework nanosheet, named as Cu-TCPP(Co) MOFs, was prepared as signal amplification strategy. Cu-TCPP(Co) MOFs/Au-ssDNA (ssDNA: single-strand DNA) was synthesized for controllable further amplification of chemiluminescent signal. The thrombin aptamer2-functionalized magnetic carbon nanotubes (MCNTs-Apt2) were used as a matrix, and Cu-TCPP(Co) MOFs/Au-ssDNA was adsorbed on the MCNTs by the complementary pairing of the partial bases between ssDNA and Apt2. Compared with ssDNA, Apt2 has a stronger interaction with thrombin. Therefore, thrombin can trigger the release of Cu-TCPP(Co) MOFs/Au-ssDNA to achieve signal amplification. Under the optimal conditions, the biosensor could detect thrombin as low as 2.178 × 10−13 mol/L with the range from 8.934 × 10−13 to 5.956 × 10−10 mol/L and exhibited excellent selectively. Moreover, the “signal-on” chemiluminescence biosensor showed potential application for the detection of thrombin in body fluids. [Display omitted] •Malg-Apt1 was prepared to separate and enrich thrombin, and the selectivity of the CL biosensor was improved.•Cu-TCPP(Co) MOFs nanosheets was prepared to provide more active sites and catalyze the reaction between luminol and H2O2.•The synthesized Cu-TCPP(Co) MOFs/Au-ssDNA as a catalyst significantly improved the sensitivity of CL biosensor.