title: Highly sensitive colorimetric detection of 17β-estradiol using split DNA aptamers immobilized on unmodified gold nanoparticles.
abstract: Gold nanoparticle (AuNP) based colorimetric aptasensor have been developed for many analytes recently largely because of the ease of detection, high sensitivity, and potential for high-throughput analysis. Most of the target aptamers for detection have short sequences. However, the approach shows poor performance in terms of detection sensitivity for most of the long-sequence aptamers. To address this problem, for the first time, we split the 76 mer aptamer of 17β-estradiol into two short pieces to improve the AuNP based colorimetric sensitivity. Our results showed that the split P1 + P2 still retained the original 76 mer aptamer's affinity and specificity but increased the detection limit by 10-fold, demonstrating that as low as 0.1 ng/mL 17β-estradiol could be detected. The increased sensitivity may be caused by lower aptamer adsorption concentration and a lower affinity to the AuNPs of a short single-strand DNA (ssDNA) sequence. Our study provided a new way to use long-sequence aptamers to develop a highly sensitive AuNP-based colorimetric aptasensor.
authors.affiliation: 1] Key Laboratory of Agro-product Quality and Safety, Institute of Quality Standards and Testing Technology for Agro-products, Chinese Academy of Agricultural Sciences, Beijing, 100081, China [2] Key Laboratory of Agri-food Quality and Safety, Ministry of Agri-culture, Beijing, 100081, China.
authors.forename: Jinchuan
authors.initials: J
authors.lastname: Liu
authors.affiliation: 1] Key Laboratory of Agro-product Quality and Safety, Institute of Quality Standards and Testing Technology for Agro-products, Chinese Academy of Agricultural Sciences, Beijing, 100081, China [2] Key Laboratory of Agri-food Quality and Safety, Ministry of Agri-culture, Beijing, 100081, China.
authors.forename: Wenhui
authors.initials: W
authors.lastname: Bai
authors.affiliation: 1] Key Laboratory of Agro-product Quality and Safety, Institute of Quality Standards and Testing Technology for Agro-products, Chinese Academy of Agricultural Sciences, Beijing, 100081, China [2] Key Laboratory of Agri-food Quality and Safety, Ministry of Agri-culture, Beijing, 100081, China.
authors.forename: Shucao
authors.initials: S
authors.lastname: Niu
authors.affiliation: 1] Key Laboratory of Agro-product Quality and Safety, Institute of Quality Standards and Testing Technology for Agro-products, Chinese Academy of Agricultural Sciences, Beijing, 100081, China [2] Key Laboratory of Agri-food Quality and Safety, Ministry of Agri-culture, Beijing, 100081, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Zhu
authors.affiliation: 1] Key Laboratory of Agro-product Quality and Safety, Institute of Quality Standards and Testing Technology for Agro-products, Chinese Academy of Agricultural Sciences, Beijing, 100081, China [2] Key Laboratory of Agri-food Quality and Safety, Ministry of Agri-culture, Beijing, 100081, China.
authors.forename: Shuming
authors.initials: S
authors.lastname: Yang
authors.affiliation: 1] Key Laboratory of Agro-product Quality and Safety, Institute of Quality Standards and Testing Technology for Agro-products, Chinese Academy of Agricultural Sciences, Beijing, 100081, China [2] Key Laboratory of Agri-food Quality and Safety, Ministry of Agri-culture, Beijing, 100081, China.
authors.forename: Ailiang
authors.initials: A
authors.lastname: Chen
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry*; D003124:Colorimetry / Q000379:methods; D004958:Estradiol / Q000032:analysis*; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*
chemical_list: D052157:Aptamers, Nucleotide; D004958:Estradiol; D006046:Gold