Novel Thymine-Functionalized Polystyrenes for Applications in Biotechnology. Polymer Synthesis and Characterization

Abstract

Novel polystyrenes (PS) carrying thymine functional groups were synthesized by copolymerizing styrene (St) and 1-(vinylbenzyl)thymine (1-VBT) in the presence and absence of divinylbenzene (DVB) in batch free radical emulsion polymerization. Microsphere latexes were obtained with an average particle size of ≈60 nm (3.0 and 5.0 wt % [VBT] 0) with ≈80% conversion and ≈38 nm (10 wt % [VBT]0) with 91% conversion. The final copolymer latexes were freeze-dried to obtain particles in the size range of 32-544 µm. Copolymer compositions were determined by FTIR-DRIFT, 1 H NMR, and elemental analysis and were found to be close to the composition of the monomer charges. XPS analysis revealed that VBT concentration on the surface of the particles was much higher (17, 24, and 36 wt %) than in the bulk. Phenol was selected as a model compound to examine adsorption onto the thymine functional groups. Hydrogen bonding between the phenolic hydroxyl group and the thymine units of soluble polymers was evidenced by 1 H NMR and FTIR spectroscopy. Adsorption isotherms obtained with all samples showed a good fit with Langmuir's model, supporting evidence for a monolayer chemisorption model in the heterogeneous adsorbent-phenol/hexane system investigated. 89.4% of the phenol was desorbed by adding Borax buffer solution of pH g 10 to the adsorbent-phenol/hexane system. These novel copolymers have potential in biotechnology.

Isolation and Characterization of 1,3-Bis(vinylbenzyl)thymine: Copolymerization with Vinylbenzyl Thymine Ammonium Chloride

“…From the GPC analysis it is likely that cross-linked network copolymers from bisVBT monomers will not be soluble, and therefore the observed GPC traces of filtered samples represent the soluble fraction of the materials with low degree of cross-linking. This might explain the unexpectedly low polydispersity (Pd) values of the copolymer molecular weights, compared to reported random VBT-VBA copolymerization reactions, which exhibit acceptable polydispersity values between 1.5 and 4 [3,26,28,29].…”

“…The study of bioinspired environmentally benign, nontoxic, and recyclable thymine-based polymers has been on a steady rise in the past decades, due to their photosensitivity and molecular recognition patterns [1][2][3][4]. A specific example of such a molecule is 1-(4-vinylbenzyl)thymine (VBT) [5,6].…”

“…Thus, VBT is often polymerized in different ratios with styrene derivative charged monomers, such as anionic vinyl phenyl sulfonate (VPS) salts [7] or cationic vinylbenzyl triethylammonium chloride (VBA) [8][9][10] which allows the copolymer to be soluble in water. Extending the knowledge achieved from the study of the natural phenomena related to thymine reactivity and intermolecular interactions has generated a diapason of potential applications [11][12][13][14] ranging from photoresist material [15,16] and organic-inorganic hybrid devices [2] to antibacterial coatings [17], drug delivery systems [3,[18][19][20], recyclable plastics [21], and biosensors [22,23]. On the other hand, the increasing attention given to the environmental and toxicological dilemmas linked to commercial materials situates the thymine-based polymeric systems as a Green Chemistry platform [24].…”

Polyisobutylene‐based biomaterials

“…90 The polymers were prepared via free-radical emulsion copolymerization of styrene and 1-(vinylbenzyl)thymine (1-VBT). XPS analysis showed that the thymine content was much higher on the surface (7-20 mol %) than in the bulk (1-4 mol %) of the PS-VBT polymers.…”

Synthesis of “bioinspired” copolymers: experimental and theoretical investigation on poly(vinyl benzyl thymine-co-triethyl ammonium chloride)

“…In addition, the existence of natural mechanisms to reverse the photo-dimerization reaction and to restore the polymers to their original state provides exciting opportunities to create fully recyclable materials (14). Some practical applications involve hair-styling products (11), electrically conductive coatings (13), antibacterial-coated surfaces (12), controlled-release drug-delivery systems (16,19), recyclable plastics (10,14), and photo-resists (5Á8,15) including fabrication of electronic components and printed circuit boards. Besides the large variety of potential applications, these thymine-based PS are environmentally-benign and consistent with the Twelve Principles of Green Chemistry (1): a non-toxic, water-soluble, and biodegradable material, which requires low energies for processing (20).…”