Selection and application of ssDNA aptamers against spermine based on Capture-SELEX

• Published in: Analytica chimica acta Vol. 1081; pp. 168 - 175
• Main Authors: Tian, Huili, Duan, Nuo, Wu, Shijia, Wang, Zhouping
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 12.11.2019
• Subjects: Animals; Aptamer; Aptamers, Nucleotide - chemistry; Capture-SELEX; DNA, Single-Stranded - chemistry; Food Contamination - analysis; Isothermal titration calorimetry; Limit of Detection; Pork; Pork Meat - analysis; SELEX Aptamer Technique - methods; Spermine; Spermine - analysis; Swine; Capture-SELEX; Aptamer; Spermine; Isothermal titration calorimetry; Pork
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2019.07.031

Spermine contamination ranks as one of the food safety issues, it will cause some adverse reactions if the intake of spermine is excessive in human body. So it is of great significance to establish fast and efficient analysis method to detect spermine in foods. In this study, the spermine aptamers with high affinity and specificity were obtained by the capture systematic evolution of ligands by exponential enrichment (Capture-SELEX) technique. Forty-one aptamer sequences were obtained by cloning and sequencing, and were divided into eight families based on homology and secondary structure analysis. The affinity and specificity of candidate aptamers was analyzed by isothermal titration calorimetry (ITC) and fluorescence assay. The aptamers named APJ-6 was picked out as the optimal aptamer that recognizes spermine specifically with the Kd value of 9.648 ± 0.896 nM. In order to verify the practicability of the selected aptamers, the sensitive aptamer-based fluorescene assay was designed. Under optimized conditions, this aptasensor exhibited a low detection limit of 0.052 nM, as well as a linear within the range of 0.1–20 nM. Besides, it has been further applied for the determination of spermine in pork samples and the recoveries ranged from 86.45% to 98.15%, showing its great potential for sensitive analysis in food safety control. [Display omitted] •Aptamers against spermine were obtained by the Capture-SELEX.•The affinity and specificity of aptamers was analyzed by ITC and fluorescence method.•Aptamer APJ-6 with Kd value of 9.648 ± 0.896 nM was obtained.•The aptasensor showed a linear range for spermine (0.1–20 nM) with LOD 0.052 nM.