Faculty Collaboration Database

In vitro enzymatic stability of dendritic peptides. J Biomed Mater Res A 2006 Feb;76(2):398-407

Date

11/05/2005

Pubmed ID

16270346

DOI

10.1002/jbm.a.30529

Scopus ID

2-s2.0-33645102601 (requires institutional sign-in at Scopus site)   27 Citations

Abstract

PEGylated polyamidoamine (PAMAM) dendrimers as drug carriers have been a topic of interest because of their biomedically favorable features, including minimal toxicity, reduced immunogenicity, and excellent solubility in aqueous and most organic solutions. A PEG shell on dendrimer surface may provide steric hindrance, known as stealth properties of PEG, to stabilize drug molecules to be delivered. In this article, the effects of PEG and coupling sequence of drug, PEG, and dendrimer in modulating the stability of delivered drug molecules were evaluated. N-succinyl-Ala-Ala-Pro-Phe-p-nitroanilide was chosen as a model peptide. Dendritic peptides, that is, peptide-dendrimer, peptide-PAMAM-PEG, and peptide-PEG-dendrimer, were constructed based on Starbursttrade mark G3.0 PAMAM dendrimer and characterized by (1)H-NMR spectroscopy. Hydrolysis of dendritic peptides was catalyzed by alpha-chymotrypsin in pH 7.4 PBS buffer containing 5% DMF (v/v) at room temperature. The enzymatic stability of dendritic peptides was peptide-PAMAM-PEG > peptide-PAMAM > free peptide > peptide-PEG-PAMAM. The ratio of PEG/peptide could be reduced for increasing peptide loading while maintaining the delivered peptides' relatively high enzymatic stability. The quantitative analysis of dendritic peptide/enzyme interactions provided the understandings of the molecular structure/stability relationships of dendrimer/drug for the design of an optimal PEGylated dendrimer-based drug-delivery system.

Author List

Yang H, Lopina ST

Author

Hu Yang PhD Chair, Professor in the Biomedical Engineering department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Biocompatible Materials
Chymotrypsin
Dendrimers
Drug Carriers
Hydrolysis
Magnetic Resonance Spectroscopy
Peptides
Polyamines
Polyethylene Glycols