Enhanced photodynamic activity of meso-tetra(4-hydroxyphenyl)porphyrin by incorporation into sub-200 nm nanoparticles

Eur J Pharm Sci. 2003 Mar;18(3-4):241-9. doi: 10.1016/s0928-0987(03)00017-4.


A photosensitizer, meso-tetra(hydroxyphenyl)porphyrin (p-THPP) was incorporated into sterile submicronic nanoparticles of poly(D,L-lactide-co-glycolide) (50:50 and 75:25 PLGA) and poly(D,L-lactide) (PLA). With all polymers used, sub-130 nm p-THPP-loaded nanoparticles with similar drug loadings and entrapment efficiencies were produced using the emulsification-diffusion technique. The photodynamic activity (photocytotoxicity) of these nanoparticles was evaluated on EMT-6 mammary tumour cells in comparison with the free drug. The influence of drug concentration (3-10 microg/ml), incubation time (5-60 min) and light dose (6-9 J/cm(2)) on p-THPP photocytotoxic efficiency was investigated. With all p-THPP formulations tested, cell viability decreased with increasing values of these parameters. The beneficial effect of nanoencapsulation compared to free drug was highlighted at drug concentrations up to 6 microg/ml and short incubation times (15-30 min). The most important photocytotoxicity was observed with 50:50 PLGA nanoparticles allowing low drug doses and short drug administration-irradiation intervals for local photodynamic therapy.

Publication types

  • Comparative Study

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Cell Survival / drug effects
  • Cell Survival / physiology
  • Dose-Response Relationship, Drug
  • Drug Delivery Systems / methods*
  • Lactic Acid / administration & dosage
  • Lactic Acid / chemistry
  • Mice
  • Nanotubes*
  • Photosensitizing Agents / administration & dosage*
  • Photosensitizing Agents / chemistry
  • Polyglycolic Acid / administration & dosage
  • Polyglycolic Acid / chemistry
  • Polylactic Acid-Polyglycolic Acid Copolymer
  • Polymers / administration & dosage
  • Polymers / chemistry
  • Porphyrins / administration & dosage*
  • Porphyrins / chemistry


  • Photosensitizing Agents
  • Polymers
  • Porphyrins
  • Polylactic Acid-Polyglycolic Acid Copolymer
  • Polyglycolic Acid
  • Lactic Acid
  • 5,10,15,20-tetra(4-hydroxyphenyl)porphyrin