Extraction and detection of bisphenol A in human serum and urine by aptamer-functionalized magnetic nanoparticles

Abstract

A new type of magnetic nanoparticles (MNPs), as the absorbents of bisphenol A (BPA), was prepared by functionalization of FeO@SiO with BPA-specific aptamer in this work. ssDNA aptamer was immobilized on the FeO@SiO surface through biotin-avidin interactions, playing a role of the specific probe for BPA. The resultant materials (Apt-MNPs) exhibited outstanding magnetic responsibility and can be separated efficiently by the magnetic field. Experimental results also showed that Apt-MNPs had large adsorption capacity and high competitive selectivity for the targeted compound BPA. Furthermore, Apt-MNPs were adopted as the specific absorbents to extract and enrich BPA from human serum and urine samples. Therefore, an efficient detection method of BPA was developed in combination with high-performance liquid chromatography (HPLC). The linearity of the method was over a range of 5-10,000 ng mL with a correlation coefficient of 0.99997, and the limit of detections (LODs) for serum and urine were 2.0 and 1.0 ng mL, respectively. The recoveries of BPA in the spiked human serum and urine samples were 90.8 ± 7.3% (RSD) and 92.3 ± 1.5%, respectively. Our results demonstrated that Apt-MNPs were high-performance adsorbents for extracting and enriching BPA, resulting in fast and efficient detection of BPA in serum and urine samples. Graphical abstract Aptamer-MNPs were effective for BPA separation from serum and urine.

Pseudo aptamer expands aptamer’s applications

“…73,74 Synthetic peptide nucleic oligomers have been used in molecular biology procedures, diagnostic assays, and antisense therapies in recent years. Due to their higher binding strength it is not necessary to design too long PNA oligomers to use, it usually requires normal oligonucleotide probes of [20][21][22][23][24][25] bases. The main concern of the length of the PNA-oligomers is to guarantee the specificity that is determined by secondary and self-assembled structures.…”

“…Various modified aptamers have also been used to diagnose disease and imaging. 20 Aptameric analytical techniques, such as electrochemistry, calorimetry, optics, mass-sensitive methods, etc., have already been developed for detections 21,22 benefited by the advantages of the convenience of modification and the stability of the aptamer. In addition to medical and analytical applications, aptamers are also a promising material for use in many other fields, such as nanomaterials.…”

ABC Spotlight on magnetic composite nanoparticles in analysis: increased sensitivity at decreased analysis time

“…Such advantages seem less obvious when utilizing modified nanoparticles to pre-concentrate samples prior to separation and analysis. Nonetheless, the last 2 years saw several approaches published in Analytical and Bioanalytical Chemistry, such as a system for pre-concentrating endocrinedisrupting compounds from water [1], or estrogenic compounds from milk [2], extracting Bisphenol A from human serum [3], or a MNP-based method for determining di(2ethylhexyl)phthalate in aqueous solutions [4]. Figure 1 shows the general approach: First, suitably functionalized Fe 3 O 4 (magnetite) nanoparticles are added to samples.…”

“…Compared to Bclassical^SPME that uses (functionalized) cartridges, MNPs allow for much faster analysis: Distributing them in the sample matrix and agitating them there substantially increases the probability that a particle meets its target analyte. The idea therefore is bringing the analytical Bdevice^-the nanoparticle extraction medium-to the sample analyte, rather than the other way round: Whereas two of the papers exposed the samples (around 100 ml) to the particles for a few hours [3,4], the other two report incubation times of 0.5-2 min for sample sizes of 1.5 and 20 ml, respectively.…”

“…These examples also highlight the use of a variety of functionalization strategies to achieve selectivity, namely modification with sodium oleate [1], coating with polydopamine [2], with molecularly imprinted polymers (MIP) [4], and aptamers [3], respectively. They cover the entire range from broad-band affinity to high selectivity during extraction.…”