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Optimizing PEGylation of TiO2 Nanocrystals through a Combined Experimental and Computational Study.

ABSTRACT: PEGylation of metal oxide nanoparticles is the common approach to improve their biocompatibility and in vivo circulation time. In this work, we present a combined experimental and theoretical study to determine the operating condition that guarantee very high grafting densities, which are desirable in any biomedical application. Moreover, we present an insightful conformational analysis spanning different coverage regimes and increasing polymer chain lengths. Based on 13C NMR measurements and molecular dynamics simulations, we show that classical and popular models of polymer conformation on surfaces fail in determining the mushroom-to-brush transition point and prove that it actually takes place only at rather high grafting density values.

SUBMITTER: Selli D

PROVIDER: S-EPMC6924593 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Optimizing PEGylation of TiO<sub>2</sub> Nanocrystals through a Combined Experimental and Computational Study.

Selli Daniele D Tawfilas Massimo M Mauri Michele M Simonutti Roberto R Di Valentin Cristiana C

Chemistry of materials : a publication of the American Chemical Society 20190809 18

PEGylation of metal oxide nanoparticles is the common approach to improve their biocompatibility and in vivo circulation time. In this work, we present a combined experimental and theoretical study to determine the operating condition that guarantee very high grafting densities, which are desirable in any biomedical application. Moreover, we present an insightful conformational analysis spanning different coverage regimes and increasing polymer chain lengths. Based on <sup>13</sup>C NMR measurem ...[more]

PMID: 31875864

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