1 research outputs found
Triple Hit with Drug Carriers: pH- and Temperature-Responsive Theranostics for Multimodal Chemo- and Photothermal Therapy and Diagnostic Applications
Currently there is a strong need
for new drug delivery systems, which enable targeted and controlled
function in delivering drugs while satisfying highly sensitive imaging
modality for early detection of the disease symptoms and damaged sites.
To meet these criteria we develop a system that integrates therapeutic
and diagnostic capabilities (theranostics). Importantly, therapeutic
efficacy of the system is enhanced by exploiting synergies between
nanoparticles, drug, and hyperthermia. At the core of our innovation
is near-infrared (NIR) responsive gold nanorods (Au) coated with drug
reservoirsmesoporous silica shell (mSi)that is capped
with thermoresponsive polymer. Such design of theranostics allows
the detection of the system using computed tomography (CT), while
finely controlled release of the drug is achieved by external trigger,
NIR light irradiationON/OFF switch. Doxorubicin (DOX) was
loaded into mSi formed on the gold core (Au@mSi-DOX). Pores were then
capped with the temperature-sensitive poly(<i>N</i>-isopropylacrylamide)-based <i>N</i>-butyl imidazolium copolymer (poly(NIPAAm-<i>co</i>-BVIm)) resulting in a hybrid systemAu@mSi-DOX@P. A 5 min
exposure to NIR induces polymer transition, which triggers the drug
release (pores opening), increases local temperature above 43 °C
(hyperthermia), and upregulates particle uptake (polymer becomes hydrophilic).
The DOX release is also triggered by drop in pH enabling localized
drug release when particles are taken up by cancer cells. Importantly,
the synergies between chemo- and photothermal therapy for DOX-loaded
theranostics were confirmed. Furthermore, higher X-ray attenuation
value of the theranostics was confirmed via X-ray CT test indicating
that the nanoparticles act as contrast agent and can be detected by
CT