Molecularly Imprinted Hybrid Adsorbents for Adenine and Adenosine-5′-triphosphate

Abstract

Submicrometer-sized silica gel particles were coated with a polyanion and a polycation bearing thymine chromophores. The polymer-coated particles were found to selectively adsorb adenine and adenosine-5'-triphosphate (ATP), as compared to other nucleobases and nucleotides, respectively. The adsorption was enhanced by the irradiation of the particles in the presence of adenine which resulted in the molecular imprinting of adenine. ATP adsorption was strongly pH-dependent.

Generation of Novel Hybrid Aptamer–Molecularly Imprinted Polymeric Nanoparticles

“…The PolyT sequence reached an even higher incorporation level, possibly due to the shorter length in comparison with the other DNA sequences tested (12 versus 30 nucleotides), which might result in an easier accessibility as well as mobility of the double‐bond moiety during the polymerization process. Changing the monomer mixture or the polymerization conditions (e.g., time or monomer) might result in an increased incorporation level, but in this instance we did not want to use excessively harsh polymerization conditions because, as we mentioned initially, another important aspect of this work is to demonstrate the stability of the DNA aptamer sequence inside the nanoparticle matrix. This stability should derive entirely from its covalent connections established on the newly introduced double‐bond moieties rather than on secondary covalent connections established because of “thymine‐dimer” structures formed following the usage of more drastic initiation systems such as UV .…”

“…Changing the monomer mixture or the polymerization conditions (e.g., time or monomer) might result in an increased incorporation level, but in this instance we did not want to use excessively harsh polymerization conditions because, as we mentioned initially, another important aspect of this work is to demonstrate the stability of the DNA aptamer sequence inside the nanoparticle matrix. This stability should derive entirely from its covalent connections established on the newly introduced double‐bond moieties rather than on secondary covalent connections established because of “thymine‐dimer” structures formed following the usage of more drastic initiation systems such as UV . In addition, we wanted to make sure that the polymerization would take place in conditions mild enough to guarantee the correct folding of the DNA sequence around the template, as well as ensuring the obtainment of a “true” nanosystem rather than a sub‐micro or microsystem …”

“…It would be interesting to test whether larger templates like proteins can be exploited to produce AptaMIPs using the method described in this work . Likewise, performing a UV polymerization process might result in a higher incorporation as well as rigidity of the polymerizable aptamer monomer and associated increase in recognition . Both these aspects are currently under investigation.…”

Evaluation of an efficient and selective adsorbent based on multi-walled carbon nanotubes coated silica microspheres for detecting nucleobases and nucleosides in human urine

“…1 Concentrations of nucleosides in urine and serum are mostly very low with the exception of uridine and uric acid, and raised concentrations in plasma and urine can be used as biomarkers for some diseases, such as diabetes, gout and cancer. water-holding adsorbents bonded with a zwitter-ionic polymer, 10 online affinity solid phase extraction systems, 11 graphene 12 and molecularly/ion imprinted polymers [13][14][15] ). To quantify nucleobases and nucleosides, biological fluids can be concentrated by vacuum drying under low temperature, freeze drying and/or drying under nitrogen.…”

Thermoresponsive and magnetic molecularly imprinted polymers based on iron oxide encapsulated carbon nanotubes as a matrix for the selective adsorption and controlled release of 2,4,5‐trichlorophenol

“…Molecular imprinting technology is an approach for incorporating affinity binding sites for target molecules in synthetic polymers; these are called molecularly imprinted polymers . This molecular recognition characteristic has been applied in several different fields, including catalysis, solid‐phase extraction, chromatography, biomedical applications, and sensors . A surface molecular imprinting technique was established on the basis of molecular imprinting through the fabrication of the molecularly imprinted polymer layer on the surface of a supporting substrate; this resulted in the improvement of the mass transfer and a reduction in the permanent entrapment of templates in traditional molecules .…”