Construction of amphiphilic copolymer nanoparticles based on
hyperbranched Poly (Amine-Ester) and 1,2-Dipalmitoyl-Sn-Glycero-3-
Phosphoethanolamine as drug carriers for cancer therapy
Yan Wu, PhD
, Fang Jiao, PhD
, Siyuan Han, BS
, Tengfei Fan, BS
, Ying Liu, PhD
Wei Li, PhD
, Liming Hu, PhD
, Yuliang Zhao, PhD
, Chunying Chen, MD
CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology, Beijing, China
Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China
College of Life Science and Bioengineering, Beijing University of Technology, Beijing, China
Received 14 January 2011; accepted 18 April 2011
Novel amphiphilic copolymer nanoparticles (HPAE-co-PLA-DPPE) composed of hyperbranched poly (amine-ester), polylactide and 1,2-
dipalmitoyl-sn-glycero-3-phosphoethanolamine (DPPE) segments were designed and synthesized that provided high encapsulation
efficiency. These nanoparticles (NPs) were used to encapsulate an antitumor model drug, doxorubicin (DOX). The resulting NPs exhibited
high encapsulation efficiency to DOX under an appropriate condition. In vitro release experiments revealed that the release of DOX from
NPs was faster at pH 4.5 than that at pH 7.4 or pH 6.0. Confocal microscopy observation indicated that the DOX-loaded NPs can enter cells
and localize in lysosomes that can be released quickly into the cytoplasm. The DOX-loaded NPs showed comparable anticancer efficacy with
the free drug both in vivo and in vitro. These results demonstrate a feasible application of the hyperbranched copolymer, HPAE-co-PLA-
DPPE, as a promising nanocarrier for intracellular delivery of antitumor drugs.
From the Clinical Editor: In this paper, the development of novel amphiphilic copolymer nanoparticles is discussed with the goal of
establishing high encapsulation efficiency for chemotherapy drugs.
© 2011 Elsevier Inc. All rights reserved.
Key words: Drug delivery; Controlled drug release; Hyperbranched copolymer; Anti-tumor activity; Biocompatibility
Polymeric micelles from amphiphilic copolymers are supra-
molecular core-shell-type nanoparticles (NPs).
fields, amphiphilic polymers have been drawing significant
attention as promising carriers in drug delivery and matrices in
The aims of utilizing the polymeric micelles
in drug delivery are to improve the solubility of water-insoluble
drugs, to stabilize and protect drugs that are sensitive to the
surrounding environment, to reduce the nonspecific uptake by the
reticuloendothelial system, to prolong the circulation time in the
blood and to achieve targeted delivery.
The most widely studied
amphiphilic polymers for drug delivery include diblock co-
polymers and triblock copolymers.
However, the conventional
micelle drug-delivery systems based on the linear amphiphilic
copolymers suffer from low encapsulation efficiency, which
limits their applications in drug delivery.
Recently, it has been
shown that amphiphilic copolymers with nonlinear structure
exhibited improved properties as drug carriers.
Dendritic polymers, including dendrimers and hyperbranched
polymers, have a highly branched structure, intramolecular
voids, small rheological volumes and lower viscosity in solution,
providing a high density of functional groups at the periphery.
Distinct from their linear analogs, hyperbranched polymers have
structures and topologies similar to dendrimers and possess some
strikingly superior material properties.
dendrimers, which often require tedious synthetic procedures,
hyperbranched polymers are more easily produced on a large
The characteristics of the abundant terminal groups have
Nanomedicine: Nanotechnology, Biology, and Medicine
7 (2011) 945 – 954
The authors acknowledge the financial support from the Ministry of
Science and Technology of China (2010CB934004 and 2011CB933401),
National Natural Science Foundation of China (31070854), the CAS
Knowledge Innovation Program and Postdoctoral Foundation of China
No conflict of interest was reported by the authors of this paper.
Corresponding author: CAS Key Laboratory for Biomedical Effects of
Nanomaterials and Nanosafety, National Center for Nanoscience and
Technology, Beijing 100190, China.
E-mail address: firstname.lastname@example.org (C. Chen).
1549-9634/$ – see front matter © 2011 Elsevier Inc. All rights reserved.
Please cite this article as: Y., Wu, et al, Construction of amphiphilic copolymer nanoparticles based on hyperbranched Poly (Amine-Ester) and 1,2-
Dipalmitoyl-Sn-Glycero-3-Phosphoethanolamine as drug carriers for cancer therapy. Nanomedicine: NBM 2011;7:945-954, doi:10.1016/j.nano.2011.04.010