writer：25． Zhimin Xing, Congling Wang, Jie Yan, Li Zhang, Lan Li, Liusheng Zha
keywords：dual stimuli responsiveness, IPN, hollow nanogels, drug delivery
source：期刊
specific source：Soft Matter, 2011, 7:7992-7997
Issue time：2011年
nanogels with an interpenetrating polymer network (IPN) structure
based on a poly(acrylic acid) (PAA) network and a poly(N-isopropylacrylamide)
(PNIPAM) network (PNIPAM/PAA IPN
hollow nanogels) were fabricated by a two-step sequential colloidal
template polymerization and subsequent removal of the cavity
templates. Their chemical composition, IPN structure and hollow
structure were verified by Fourier transformation infrared spectroscopy
(FTIR) and transmission electron microscopy (TEM),
respectively. pH and temperature dependent particle sizes measured
by dynamic light scattering indicated that the hollow nanogels have
both pH and temperature dual stimuli responsive properties. Isoniazid
(INH), an antitubercular drug, was loaded into PNIPAM/PAA
IPN hollow nanogels by controlling the equilibrium temperature
ensuring it is lower than their volume phase transition temperature,
so that the drug loading capacity can reach 668 mg INH per gram of
the hollow nanogel. It can be seen from the TEM results that the
encapsulated INH is mainly located in the cavities of the hollow
nanogels. In vitro drug release studies showed that the INH loaded
PNIPAM/PAA IPN hollow nanogels possess distinct acid triggered
drug release behavior, which may make them suitable for a stomachspecific
drug delivery system.