Porphyrin-containing polyaspartamide gadolinium complexes as potential magnetic resonance imaging contrast agents

Int J Pharm. 2011 Apr 4;407(1-2):119-25. doi: 10.1016/j.ijpharm.2011.01.036. Epub 2011 Jan 25.

Abstract

Porphyrin-containing polyaspartamide ligands (APTSPP-PHEA-DTPA) were synthesized by the incorporation of diethylenetriaminepentaacetic acid (DTPA) and 5-(4'-aminophenyl)-10,15,20-tris(4'-sulfonatophenyl) porphyrin, trisodium salt (APTSPP) into poly-α,β-[N-(2-hydroxyethyl)-l-aspartamide] (PHEA). These ligands were further reacted with gadolinium chloride to produce macromolecule-gadolinium complexes (APTSPP-PHEA-DTPA-Gd). Experimental data of (1)H NMR, IR, UV and elemental analysis evidenced the formation of the polyaspartamide ligands and gadolinium complexes. In vitro and in vivo property tests indicated that APTSPP-PHEA-DTPA-Gd possessed noticeably higher relaxation effectiveness, less toxicity to HeLa cells, and significantly higher enhanced signal intensities (SI) of the VX2 carcinoma in rabbits with lower injection dose requirement than that of Gd-DTPA. Moreover, APTSPP-PHEA-DTPA-Gd was found to greatly enhance the contrast of MR images of the VX2 carcinoma, providing prolonged intravascular duration, and distinguished the VX2 carcinoma and normal tissues in rabbits according to MR image signal enhancements. These porphyrin-containing polyaspartamide gadolinium complexes can be used as the candidates of contrast agents for targeted MRI to tumors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Carcinoma / diagnosis
  • Carcinoma / pathology
  • Contrast Media* / administration & dosage
  • Contrast Media* / chemical synthesis
  • Dose-Response Relationship, Drug
  • Gadolinium / chemistry*
  • HeLa Cells
  • Humans
  • Magnetic Resonance Imaging / methods*
  • Neoplasms, Experimental / diagnosis
  • Neoplasms, Experimental / pathology
  • Organometallic Compounds / chemistry
  • Pentetic Acid / chemistry
  • Peptides / chemistry
  • Porphyrins / chemistry*
  • Proteins / chemistry
  • Rabbits

Substances

  • Contrast Media
  • Organometallic Compounds
  • Peptides
  • Porphyrins
  • Proteins
  • alpha,beta-poly((2-hydroxyethyl)-aspartamide)
  • Pentetic Acid
  • Gadolinium