1 research outputs found
Validation of Smart Nanoparticles as Controlled Drug Delivery Systems: Loading and pH-Dependent Release of Pilocarpine
Micelles are good
devices for use as controlled drug delivery systems
because they exhibit the ability to protect the encapsulated substance
from the routes of degradation until they reach the site of action.
The present work assesses loading kinetics of a hydrophobic drug,
pilocarpine, in polymeric micellar nanoparticles (NPs) and its pH-dependent
release in hydrophilic environments. The trigger pH stimulus, pH 5.5,
was the value encountered in damaged tissues in solid tumors. The
new nanoparticles were prepared from an amphiphilic block copolymer,
[(HEMA<sub>19%</sub>-DMA<sub>31%</sub>)-(FMA<sub>5%</sub>-DEA<sub>45%</sub>)]. For the present research, three systems were validated,
two of them with cross-linked cores and the other without chemical
stabilization. A comparison of their loading kinetics and release
profiles is discussed, with the support of additional data obtained
by scanning electron microscopy and dynamic light scattering. The
drug was loaded into the NPs within the first minutes; the load was
dependent on the degree of cross-linking. All of the systems experienced
a boost in drug release at acidic pH, ranging from 50 to 80% within
the first 48 h. NPs with the highest degree (20%) of core cross-linking
delivered the highest percentage of drug at fixed times. The studied
systems exhibited fine-tuned sustained release features, which may
provide a continuous delivery of the drug at specific acidic locations,
thereby diminishing side effects and increasing therapeutic rates.
Hence, the studied NPs proved to behave as smart controlled drug delivery
systems capable of responding to changes in pH