Fabrication and Characterization of Hollow Microcapsules from Polyelectrolytes Bearing Thymine Pendant Groups for Ultraviolet‐B (UVB)‐Induced Crosslinking

GIMÉNEZ, RODRIGO E.; SERRANO, MARIANA P.; ÁLVAREZ, ROSA MARÍA S.; MARTINO, DÉBORA M.; BORSARELLI, CLAUDIO D.

ChemPlusChem

Wiley-VCH

Año: 2019 vol. 84 p. 504 - 511

2192-6506

DNA ? bioinspired polyelectrolytes poly[vinylbenzylthymine(VBT)-4-vinylbenzyltriethylammonium chloride (VBA)] and poly[vinylbenzylthymine (VBT)-4-vinylphenylsufonate (VPS)] wereused for the preparation of hollow microcapsules (HMC) usingthe layer-by-layer method and CaCO3 microspheres as removablemolds. Stable aqueous suspensions of spherical-shapedHMCs with a shell composed of six layers of VBA-basedpolyelectrolytes were obtained, of approximately (7.0�1.5) μmdiameter and a shell thickness of 1 μm. Ultraviolet-B irradiationof the HMC suspensions induces an efficient crosslinkingbetween adjacent polyelectrolyte chains through the formationof thymine photodimers, such as the cyclobutane pyrimidinedimer (CPD) and the (6?4) pyrimidine?pyrimidone photoproduct(6?4PP). This process resulted in a reduction of the averageinterstitial mesh size of the HMC shells, modulating theirpermeability properties and increasing the mechanical stabilityof the HMC without a noticeable modification of size and shape.Thus, the DNA-bioinspired polyelectrolytes are promisingmaterials for the preparation of UVB-responsive HMCs.