Upconversion luminescence resonance energy transfer-based aptasensor for the sensitive detection of oxytetracycline

详细信息    查看全文

• 作者：Hui Zhang^a ; Congcong Fang^b ; Shijia Wu^b ; ^{wusj1986@163.com" class="auth_mail" title="E-mail the corresponding author} ; Nuo Duan^b ; Zhouping Wang^b ; ^{wangzp1974@163.com" class="auth_mail" title="E-mail the corresponding author}
• 关键词：Oxytetracycline ; Aptamer ; Luminescence resonance energy transfer ; Upconversion nanoparticles
• 刊名：Analytical Biochemistry
• 出版年：2015
• 出版时间：15 November 2015
• 年：2015
• 卷：489
• 期：Complete
• 页码：44-49
• 全文大小：1351 K

文摘

In this work, a biosensor based on luminescence resonance energy transfer (LRET) from NaYF₄:Yb,Tm upconversion nanoparticles (UCNPs) to SYBR Green I has been developed. The aptamers are covalently linked to UCNPs and hybridized with their complementary strands. The subsequent addition of SYBR Green allows SYBR Green I to insert into the formed double-stranded DNA (dsDNA) duplex and brings the energy donor and acceptor into close proximity, leading to the fluorescence of UCNPs transferred to SYBR Green I. When excited at 980 nm, the UCNPs emit luminescence at 477 nm, and this energy is transferred to SYBR Green I, which emits luminescence at 530 nm. In the presence of oxytetracycline (OTC), the aptamers prefer to bind to its corresponding analyte and dehybridize with the complementary DNA. This dehybridization leads to the liberation of SYBR Green I, which distances SYBR Green I from the UCNPs and recovers the UCNPs' luminescence. Under optimal conditions, a linear calibration is obtained between the ratio of I₅₃₀ to I₄₇₇ nm (I₅₃₀/I₄₇₇) and the OTC concentration, which ranges from 0.1 to 10 ng/ml with a limit of detection (LOD) of 0.054 ng/ml.