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

471283

Sigma-Aldrich

Triethylamine, ≥99.5%

S7795

Sigma-Aldrich

Sodium carbonate, BioXtra, ≥99.0%

E2385

Supelco

Ethanol standards 10% (v/v), 10 % (v/v) in H₂O, analytical standard

2858

Sigma-Aldrich

Ethanol Fixative 80% v/v, suitable for fixing solution (blood films)

T0886

Sigma-Aldrich

Triethylamine, ≥99%

71363

Supelco

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

90340

Sigma-Aldrich

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

90338

Sigma-Aldrich

Triethylamine, ampule, ≥99.5% (GC)

90337

Sigma-Aldrich

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

90335

Sigma-Aldrich

Triethylamine, BioUltra, ≥99.5% (GC)

71631

Sigma-Aldrich

Sodium bicarbonate, tested according to Ph. Eur.

71345

Sigma-Aldrich

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

S6297

Sigma-Aldrich

Sodium bicarbonate, BioXtra, 99.5-100.5%

PHR1070

Supelco

Dehydrated Alcohol, Pharmaceutical Secondary Standard; Certified Reference Material

V900801

Sigma-Aldrich

Sodium carbonate, Vetec^™, reagent grade, ≥99.5%

E7148

Sigma-Aldrich

Ethyl alcohol, Pure 190 proof, for molecular biology

S5761

Sigma-Aldrich

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

451614

Sigma-Aldrich

Sodium carbonate, anhydrous, powder, 99.999% trace metals basis

V900182

Sigma-Aldrich

Sodium bicarbonate, Vetec^™, reagent grade, 99%

48075

Supelco

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

900504

Sigma-Aldrich

Sodium carbonate, anhydrous, free-flowing, Redi-Dri^™, ACS reagent (primary standard), 99.95-100.05% dry basis

900505

Sigma-Aldrich

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

900506

Sigma-Aldrich

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

13433

Sigma-Aldrich

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

900503

Sigma-Aldrich

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

791768

Sigma-Aldrich

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

73487

Supelco

Triethylamine, analytical standard

223484

Sigma-Aldrich

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

222321

Sigma-Aldrich

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

S6014

Sigma-Aldrich

Sodium bicarbonate, ACS reagent, ≥99.7%