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

179272

Sigma-Aldrich

Diethyl ether

451614

Sigma-Aldrich

Sodium carbonate, powder, 99.999% trace metals basis

471283

Sigma-Aldrich

Triethylamine, ≥99.5%

48075

Supelco

Ethanol solution, certified reference material, 2000 μg/mL in methanol

PHR1070

Supelco

Dehydrated Alcohol, Pharmaceutical Secondary Standard; Certified Reference Material

91238

Supelco

Diethyl ether, analytical standard

71345

Sigma-Aldrich

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

90337

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

90335

Sigma-Aldrich

Triethylamine, BioUltra, ≥99.5% (GC)

90340

Sigma-Aldrich

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

90338

Sigma-Aldrich

Triethylamine, ampule, ≥99.5% (GC)

71363

Supelco

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

71631

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Sodium bicarbonate, tested according to Ph. Eur.

W424601

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Triethylamine, ≥99.5%

S6297

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Sodium bicarbonate, BioXtra, 99.5-100.5%

T0886

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Triethylamine, ≥99%

S5761

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S7795

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Sodium carbonate, BioXtra, ≥99.0%

1012772

USP

Dehydrated Alcohol, United States Pharmacopeia (USP) Reference Standard

346144

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

222321

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Sodium carbonate, ACS reagent, anhydrous, ≥99.5%, powder or granules

223484

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Sodium carbonate, ACS reagent (primary standard), anhydrous, 99.95-100.05% dry basis

401676

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Sodium hydrogencarbonate, −40-+140 mesh, ≥95%

791768

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

900506

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Sodium bicarbonate, anhydrous, free-flowing, Redi-Dri^™, ReagentPlus^®, ≥99.5%

676845

Sigma-Aldrich

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

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Sodium carbonate, ReagentPlus^®, ≥99.5%

792519

Sigma-Aldrich

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Sigma-Aldrich

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