A novel polymer-paclitaxel conjugate based on amphiphilic triblock copolymer

J Control Release. 2007 Feb 12;117(2):210-6. doi: 10.1016/j.jconrel.2006.11.014. Epub 2006 Nov 23.

Abstract

A novel amphiphilic polymer-paclitaxel conjugate P(LGG-paclitaxel)-PEG-P(LGG-paclitaxel) has been prepared. It was derived from its parent polymer P(LGG)-PEG-P(LGG), poly{(lactic acid)-co-[(glycolic acid)-alt-(l-glutamic acid)]}-block-poly(ethylene glycol)-block-poly{(lactic acid)-co-[(glycolic acid)-alt-(l-glutamic acid)]}, which was prepared by ring-opening copolymerization of l-lactide (LLA) with (3s)-benzoxylcarbonylethyl-morpholine-2,5-dione (BEMD) in the presence of dihydroxyl PEG with molecular weight of 4600 as a macroinitiator using stannous octoate (Sn(Oct)(2)) as catalyst, and by subsequent catalytic hydrogenation. It could self-assemble into micelles in an aqueous system with P(LGG-paclitaxel) block in the core and PEG in the shell. ESEM and DLS analysis of the micelles revealed a homogeneous spherical morphology and a unimodal size distribution. In vitro release of paclitaxel from the conjugate micelles showed that its release rate depended on pH value and was higher at lower pH than in neutral condition. In vitro antitumor activity of the paclitaxel conjugate against rat brain glioma C6 cells was evaluated by MTT method. The results showed that the paclitaxel can be released from the conjugate without losing cytotoxicity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antineoplastic Agents, Phytogenic / administration & dosage
  • Antineoplastic Agents, Phytogenic / chemistry
  • Antineoplastic Agents, Phytogenic / pharmacology
  • Biological Availability
  • Cell Line, Tumor
  • Cell Survival / drug effects
  • Delayed-Action Preparations / chemical synthesis
  • Delayed-Action Preparations / chemistry
  • Drug Delivery Systems / methods
  • Hydrogen-Ion Concentration
  • Magnetic Resonance Spectroscopy
  • Micelles
  • Microscopy, Electron, Scanning
  • Molecular Weight
  • Paclitaxel / administration & dosage
  • Paclitaxel / chemistry*
  • Paclitaxel / pharmacology
  • Particle Size
  • Polyesters / chemical synthesis
  • Polyesters / chemistry*
  • Polyethylene Glycols / chemical synthesis
  • Polyethylene Glycols / chemistry*

Substances

  • Antineoplastic Agents, Phytogenic
  • Delayed-Action Preparations
  • Micelles
  • Polyesters
  • poly(lactic acid-co-((glycolic acid)-alt-(L-glutamic acid))glucose)-poly(ethylene glycol)-poly(lactic acid-co-((glycolic acid)-alt-(L-glutamic acid))glucose)
  • Polyethylene Glycols
  • Paclitaxel