Background: The poor retention and penetration are the major issues in the bioavailability
of drugs through ocular route. Recently, the natural polymers have been exploited for the development
of nanoparticles to improve the ocular performance of various drugs. In the present investigation,
nanoparticles of timolol maleate (TM) were developed by using chitosan polymer to improve its release
through ocular delivery.
Method: Ionic gelation method was used for the development of timolol loaded chitosan nanoparticles
by using a cross linking agent, sodium tripolyphosphate (NaTPP). The Box- Behnken design was used
for the optimization of various parameters for the development of nanoparticles.
Objective: The objective behind the study was to study the effect of three critical parameters; concentration
of chitosan (X1), the concentration of NaTPP (X2), and the volume of NaTPP (X3) on the drug
release from the prepared nanoparticles.
Results: The results obtained showed that high level of the chitosan concentration and low level of the
NaTPP concentration and the mid levels of the NaTPP volume resulted in high levels of encapsulation
efficiency. The loading capacity was found maximum at a low level of chitosan and mid level of volume
of the NaTPP with a low level of NaTPP concentration. The optimized batch (NP-2) showed that
the entrapment efficiency was 75.34±0.17%, the particle size of 190.9 nm and in vitro cumulative percentage
of drug release was 49.11±0.49% in 12 h.
Conclusion: The study concluded that chitosan nanoparticles loaded with timolol maleate resulted in
improved drug release for ocular treatment.