5,6-Dihydroxyindole-2-carboxylic-Acid-TiO2 Charge Transfer Complexes in the Radical Polymerization of Melanogenic Precursor(s)

被引：37

作者：

Vitiello, Giuseppe ^{[1
,2
]}

Pezzella, Alessandro ^{[3
,4
]}

Calcagno, Vincenzo ^{[5
]}

Silvestri, Brigida ^{[1
]}

Raiola, Luca ^{[5
]}

D'Errico, Gerardino ^{[2
,3
]}

Costantini, Aniello ^{[1
]}

Branda, Francesco ^{[1
]}

Luciani, Giuseppina ^{[1
]}

机构：

[1] Univ Naples Federico II, Dept Chem Mat & Prod Engn, Ple V Tecchio 80, I-80125 Naples, Italy

[2] Consorzio Interuniv Sviluppo Sistemi & Grande Int, CSGI, Via Lastruccia 3, I-50019 Florence, Italy

[3] Univ Naples Federico II, Dept Chem Sci, Via Cintia 4, I-80126 Naples, Italy

[4] CNR, IPCB, Via Campi Flegrei 34, I-80078 Naples, Italy

[5] IIT, Ctr Adv Biomat Hlth Care CRIB, Via Largo Barsanti & Matteucci 53, I-80125 Naples, Italy

来源：

JOURNAL OF PHYSICAL CHEMISTRY C | 2016年 / 120卷 / 11期

关键词：

AEROBIC OXIDATION; TIO2; SURFACES; MELANIN; ACID; PHOTOCATALYSIS; EUMELANIN; NANOPARTICLES; POLYDOPAMINE; REDUCTION; MECHANISM;

D O I：

10.1021/acs.jpcc.6b00226

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

A combination of biomedical and technological applications is generating, over the past decades, the well established interest toward melanins and melanogenesis. Several compounds have been explored to promote/catalyze oxidative polymerization of melanogenic precursors, such as 5,6-dihydroxyindole-2-carboxylic acid (DHICA), to melanin-like biopolymers in vitro. TiO2 has shown a photocatalytic activity driving DHICA polymerization and leading to the formation of melanin-TiO2 hybrid nanostructures with unique biocide behavior even under visible light. However, the mechanism of melanin formation in those hybrids is not yet well understood although a ligand to metal charge transfer (LMCT) process involving DHICA and Ti4+ ions was hypothesized. Here, we focus on melanin formation and apply a complementary analysis, by using photoluminescence (PL), UV-vis, electron paramagnetic resonance (EPR), and nuclear magnetic resonance (NMR) spectroscopy to reveal the mechanism of DHICA polymerization in the presence of a TiO2-sol. This study discloses TiO2 potentialities to drive and template DHICA polymerization to melanin via LMCT-based photo-oxidative process.

引用

页码：6262 / 6268

页数：7

共 39 条

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