Synergy of Post-Crosslinked imprinting strategy and silanol chemistry for the anisotropic construction of molecularly imprinted polymers onto Halloysite nanotubes

Abstract

Searching for alternative porous substrates which can realize anisotropic preparation of “tailor-made” complementary binding sites is an important way to improve the identification efficiency and interfacial stability of the surface molecularly imprinted polymers (SMIPs). In this work, a functional polymer (FP) with multi-functional properties was firstly synthesized using 3-(isobutenyloxy) propyltrimethoxysilane, 1-(vinylbenzyl) thymidine and cinnamoyloxyethyl methacrylate (CEMA) as monomers, and then FP with post-crosslinking property was covalently deposited onto theoutersurfaceof halloysite nanotubes (HNTs) using silanol chemistry to prepare 2′-deoxyadenosine (dA) imprinted sorbents (HNTs-SMIPs). More than 65 % of dA molecules was captured within the first 2.0 h. The number of high affinity site from the total binding sites of HNTs-SMIPs is estimated to be as high as 73.25 %, and the maximum adsorption amount of HNTs-SMIPs is 48.78 μmol g -1 at 25 °C. The imprinting factor (IF) of HNTs-SMIPs towards dA is 1.89, and 79.49 % the adsorption capacity is remained after five adsorption–desorption cycles. In addition, 70.2 % of the dA from spiked human urine samples can be selectively extracted by HNTs-SMIPs. HNTs-SMIPs have excellent interfacial stability and strong affinity for the template molecule dA, and this work provides a new strategy for the specific separation and enrichment of dA.