Graphite nanoparticle as nanoquencher for 17β-estradiol detection using shortened aptamer sequence

Abstract

A graphite nanoparticle (GN) with a spherical shape and stacked by a few layered graphene sheets is an ideal fluorescent nanoquencher for the fluorophore. We developed a novel aptasensor based on fluorescence resonance energy transfer for the sensitive and specific detection of 17β-estradiol (E2) by using the GN as a fluorescent nanoquencher and the shorter E2 specific aptamer as the sensing probe. The physiological and chemical properties of the aptasensor in response to the E2 capture were investigated with an atomic force microscopic analysis and an E2 detection principle was clarified accordingly. Also, it was demonstrated that the sensitivity of the aptasensor was affected by the length of aptamer and the particle size of the nanoquencher, and the highest sensitivity for E2 detection was achieved with a shorter aptamer of 35 base sequences and a smaller GN with a particle size of around 5 nm. And the detection limit was 1.02 ng mL-1. Moreover, this presented no cross reaction with E2 analogs and was successfully utilized for the real environmental water monitoring.

One-Pot SELEX: Identification of Specific Aptamers against Diverse Steroid Targets in One Selection

“…25 Of the various reported estradiol aptamers, those developed by Kim et al 26 and Alsager et al 27 have been widely adopted in various applications. 28−31 In the case of progesterone, only one aptamer has been reported to date, 32 which has been exploited 33,34 despite the fact that it cross reacts with other steroids. 33−35 Finally, testosterone-binding aptamers have been reported 36 but to date, no application of this aptamer has been reported.…”

“…Steroids belong to a family of hormones involved in many physiological processes and are used as biomarkers in many fields, including reproductive health, , cancer diagnostics as well as in doping control, and the detection of environmental pollutants. , Steroid-binding aptamers have already been reported, with the majority of these reports targeting estradiol, and their binding properties were evaluated in a previous work . Of the various reported estradiol aptamers, those developed by Kim et al and Alsager et al have been widely adopted in various applications. − In the case of progesterone, only one aptamer has been reported to date, which has been exploited , despite the fact that it cross reacts with other steroids. − Finally, testosterone-binding aptamers have been reported but to date, no application of this aptamer has been reported. The structural similarities between steroids are quite high thus obtaining aptamers with high specificity for these small molecules is a challenging task.…”

A self-powered electrochemical aptasensor for the detection of 17β-estradiol based on carbon nanocages/gold nanoparticles and DNA bioconjugate mediated biofuel cells

“…27,28 Accordingly, developing efficient and sensitive methods for the monitoring of E2 levels is of great significance. So far, many different techniques have been established for the determination of E2, such as gas chromatography/ liquid chromatography-mass spectrometry (GC/LC-MS), 29,30 enzyme-linked immunosorbent assay (ELISA), 31,32 colorimetry, [33][34][35] fluorescence, [36][37][38][39] electrochemistry, [40][41][42][43][44][45][46] and surface-enhanced Raman spectroscopy. 47,48 Nevertheless, these methods might suffer from the high cost of devices, the need for high levels of technical skill, low sensitivity, cumbersome operation processes and the need for sample pretreatment.…”

A “turn-on” fluorescence resonance energy transfer aptasensor based on carbon dots and gold nanoparticles for 17β-estradiol detection in sea salt

“…A FRET aptasensor based on a fluorescence dye label as the donor and a spherical graphite nanoparticle as the fluorescent nanoquencher was developed for 17β-estradiol detection. 23 However, semiconductor QDs are highly toxic, and organic dyes are easy to photobleach and have poor light stability. 24 Carbon dots (CDs) have the advantages of low toxicity, low cost, and environmental friendliness.…”