writer：Cong Cheng, Yan Gao,* Weihua Song, Qiang Zhao, Haisong Zhang, and Hailei Zhang *
keywords：halloysite nanotube; clay science; H2O2-responsive; drug loading.
source：期刊
specific source：Chemical Engineering Journal
Issue time：2019年

In this paper, a

novel halloysite-based hydrogel with a “turn-on” fluorescence character upon H2O2

was facilely prepared and used to construct the H2O2-responsive

drug delivery system, in which a coprecipitation

method was proposed to afford the drug-loaded halloysite

nanotubes

(DHNTs). DHNTs were carefully characterized by

FTIR, TGA, XPS, XRD and TEM to demonstrate that the drugs were mainly loaded

into the cavity rather than attached on the external surface of halloysite nanotubes (HNTs). The B-C linkage in the

as-prepared hydrogel was broken in the presence of H2O2,

resulting in the degradation and thereby a responsive

release. The drug release was almost not occurred under the

physiological concentration ([H2O2] = 0.02 μM), while a

complete release (>90%) can be achieved under pathological concentration

([H2O2] = 200 μM). Moreover, the broken of B-C linkage

triggered a transformation from arylboronates to phenols,

in which the formed fluorescein gave rise to the change from non-fluorescent

to fluorescent of the hydrogels.

The fluorescence intensity enhanced

with the increase of release rate, in which a good linear relationship can be

achieved. The attractive properties make the halloysite-based

hydrogels a promising

application in the field of biomedicine.