title: High affinity truncated DNA aptamers for the development of fluorescence based progesterone biosensors.
abstract: Aptamers have shown a number of potential applications in sensing and therapeutic due to the high affinity and specificity towards their target molecules. Not all the nucleotides in the full length aptamers are involved in the binding with their targets. The non-binding domain of the aptamer may affect the binding affinity of the aptamer-target complex. Mapping the aptamer binding region could increase the affinity and the specificity. In this paper, we designed aptamer-based fluorescence sensors from a truncated progesterone (P4) aptamer. Then, fluorescein and quencher labelled aptamer complementary oligonucleotide sequences were hybridized to the truncated aptamer at different sites to form duplex structures. We used fluorescence-quencher pair displacement assay upon progesterone binding for the determination of P4. One of the truncated sequences has shown high binding affinity with 16 fold increase in the dissociation constant, Kd(2.1 nM) compared to the original aptamer. The aptasensor was highly selective for P4 against similar compounds such as 17-β estradiol, bisphenol-A and vitamin D. The sensor has been applied for the detection of P4 in spiked tap water and in urine samples showing good recovery. This new developed aptamer-based fluorescence biosensor can be applied in food, pharmaceutical, and clinical industries.
authors.affiliation: Faculty of Applied Medical Sciences, King Abdulaziz University, Post Office Box 80402, Jeddah 21589, Saudi Arabia.
authors.forename: Hani A
authors.initials: HA
authors.lastname: Alhadrami
authors.affiliation: Department of Chemistry, Alfaisal University, Al Zahrawi Street, Al Maather, AlTakhassusi Rd, Riyadh 11533, Saudi Arabia.
authors.forename: Raja
authors.initials: R
authors.lastname: Chinnappan
authors.affiliation: Department of Chemistry, Alfaisal University, Al Zahrawi Street, Al Maather, AlTakhassusi Rd, Riyadh 11533, Saudi Arabia.
authors.forename: Shimaa
authors.initials: S
authors.lastname: Eissa
authors.affiliation: King Faisal Specialist Hospital and Research Center, Zahrawi Street, Al Maather, Riyadh 12713, Saudi Arabia.
authors.forename: Anas Abdel
authors.initials: AA
authors.lastname: Rahamn
authors.affiliation: Department of Chemistry, Alfaisal University, Al Zahrawi Street, Al Maather, AlTakhassusi Rd, Riyadh 11533, Saudi Arabia; King Faisal Specialist Hospital and Research Center, Zahrawi Street, Al Maather, Riyadh 12713, Saudi Arabia. Electronic address: mzourob@alfaisal.edu.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Zourob
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods*; D015342:DNA Probes / Q000737:chemistry*; D005453:Fluorescence; D006801:Humans; D011374:Progesterone / Q000032:analysis*; D016482:Urinalysis; D014556:Urine / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
chemical_list: D052157:Aptamers, Nucleotide; D015342:DNA Probes; D014867:Water; D011374:Progesterone
keywords: Aptamers; Hormones in water; Progesterone