化工专业英语求翻译

Hollow polymeric spheres have been attracting increasing interest because of their potential applications， which range from targeted drug delivery to advanced functional materi- als.[1，2] Because of their hollow core structure， such poly... Hollow polymeric spheres have been attracting increasing
interest because of their potential applications， which range
from targeted drug delivery to advanced functional materi-
als.[1，2] Because of their hollow core structure， such polymeric
spheres can encapsulate large quantities of guest moleculesÐ
especially those spheres with functionalities within the empty
coreÐand release them at a later stage in a controlled man-
ner. Although hollow polymeric spheres with dimensions in
the micrometer and submicrometer regions are readily con-
structedÐby layer-by-layer deposition of polyelectrolytes
onto a template core，[3±6] polymerizing monomers in lipid vesi-
cles，[7，8] emulsion polymerization，[9，10] pH-induced micelliza-
tion of a grafted copolymer，[11] and by the assembly of posi-
tively charged polyelectrolytes and negatively charged
nanoparticles[12]Ðthe synthesis of hollow spheres 100 nm or
less in size has only recently become the subject of research
activity. Several different routes， such as the self-assembly of
block copolymers in a selective solvent，[13，14] the deposition of
polyelectrolytes on a decomplexable or soluble core，[15，16] and
microemulsion (as well as miniemulsion) polymerization，[17，18]
have been developed to form hollow polymeric nanospheres.
Although some of these methods have been quite successful，
these strategies require the core templates to be removed in
order to create a hollow interior， or need large quantities of
surfactants to form nanosized micelles. Furthermore， although
the majority of the proposed applications of hollow nano-
spheres or nanocapsules are concentrated in the biomedical
field， most of the hollow polymeric spheres described to date
are ill-suited for such purposes. Therefore， materials (in par-
ticular for the surfaces of the hollow nanospheres) that are
biocompatible， non-toxic， and sometimes also biodegradable，
are highly desirable. Herein， we demonstrate a simple and di-
rect method for fabricating hollow polymeric nanospheres
with biocompatible and biodegradable macromolecules. In
this approach， hollow polymeric nanospheres were formed in
a completely aqueous system without the aid of surfactants，