A novel folic acid-conjugated TiO₂-SiO₂ photosensitizer for cancer targeting in photodynamic therapy.

A novel folic acid-conjugated TiO₂-SiO₂ photosensitizer for cancer targeting in photodynamic therapy.

Colloids and surfaces. B, Biointerfaces (2014-12-17)

Xiaohui Feng, Shaokun Zhang, Hong Wu, Xia Lou

ABSTRACT

In this paper, a novel folic acid-conjugated silica-coated titanium dioxide (TiO2-SiO2) photosensitizer was synthesized and characterized using various analytical instruments. The photosensitizer was further assessed with regards to its photoreactivity, cellular and hemocompatibility, cell internalization, and phototoxicity. Conjugating folic acid with TiO2-SiO2 has shown a significantly improved compatibility of the nanoparticles with the mouse fibroblast cells (L929) at 24 h. An improved compatibility with the human nasopharyngeal epidermoid cancer (KB) cells was also demonstrated, but to a slightly reduced degree. Enhanced cell internalization was well demonstrated in the TiO2-SiO2 folate nanoparticles. Upon exposure to UV light, TiO2-SiO2 folate nanoparticles maintained a high level photodynamic reactivity and yielded a 38-43% photo-killing of KB cells. The photo-killing effect increased with increasing dosage in the investigated concentration range of 50-100 μg ml(-1).

MATERIALS

Product Number

Brand

Product Description

S5761

Sigma-Aldrich

Sodium bicarbonate, powder, BioReagent, Molecular Biology, suitable for cell culture, suitable for insect cell culture

S6297

Sigma-Aldrich

Sodium bicarbonate, BioXtra, 99.5-100.5%

S7795

Sigma-Aldrich

Sodium carbonate, BioXtra, ≥99.0%

71631

Sigma-Aldrich

Sodium bicarbonate, tested according to Ph. Eur.

71363

Supelco

Sodium carbonate, reference material for titrimetry, certified by BAM, >99.5%

71345

Sigma-Aldrich

Sodium carbonate, BioUltra, anhydrous, ≥99.5% (calc. on dry substance, T)

673811

Sigma-Aldrich

Diethyl ether, anhydrous, ACS reagent, ≥99.0%, contains BHT as inhibitor

346136

Sigma-Aldrich

Diethyl ether, ACS reagent, anhydrous, ≥99.0%, contains BHT as inhibitor

346144

Sigma-Aldrich

Diethyl ether, reagent grade, ≥98%, contains ≤2% ethanol and ≤10ppm BHT as inhibitor

676845

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Diethyl ether, ACS reagent, ≥98.0%, contains ≤2% ethanol and ≤10ppm BHT as inhibitor

309966

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Diethyl ether, suitable for HPLC, ≥99.9%, inhibitor-free

73487

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Triethylamine, analytical standard

90340

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Triethylamine, puriss. p.a., ≥99.5% (GC)

90335

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90337

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Triethylamine, for amino acid analysis, ≥99.5% (GC)

90338

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Triethylamine, ampule, ≥99.5% (GC)

W424601

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Triethylamine, ≥99.5%

91238

Supelco

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451614

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471283

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Triethylamine, ≥99.5%

179272

Sigma-Aldrich

Diethyl ether

T0886

Sigma-Aldrich

Triethylamine, ≥99%

791768

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Sodium carbonate, anhydrous, free-flowing, Redi-Dri^™, ACS reagent, ≥99.5%

13433

Sigma-Aldrich

Sodium bicarbonate, puriss., meets analytical specification of Ph. Eur., BP, USP, FCC, E500, 99.0-100.5%, powder

S6014

Sigma-Aldrich

Sodium bicarbonate, ACS reagent, ≥99.7%

900506

Sigma-Aldrich

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S8875

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Sodium bicarbonate, ReagentPlus^®, ≥99.5%, powder

S2127

Sigma-Aldrich

Sodium carbonate, ReagentPlus^®, ≥99.5%

792519

Sigma-Aldrich

Sodium bicarbonate, anhydrous, free-flowing, Redi-Dri^™, ACS reagent, ≥99.7%

1613655

USP

Sodium bicarbonate, United States Pharmacopeia (USP) Reference Standard