Purpose: To formulate solidified reverse micellar solutions (SRMS)-based solid lipid microparticles
(SLMs) using homolipid from
Capra hircus
, and evaluate its suitability for the delivery of gentamicin.
Methods: SLMs were formulated by melt-emulsification using SRMS (15 % w/w Phospholipon® 90G in
35 % w/w
Capra hircus), PEG 4000 and gentamicin (1.0, 2.0 and 3.0 % w/w), and characterized with
respect to size, morphology, encapsulation efficiency (EE) and pH-dependent stability. In vitro release
of gentamicin from the SLMs was performed in phosphate buffer (pH 7.4) while bioevaluation was
carried out using clinical isolates of
Pseudomonas aeruginosa
and
Staphylococcus aureus
.
Results: Stable and discrete SLMs of size range 1.47 ± 0.02 to 3.55 ± 0.09 ìm were obtained. The
SLMs showed a biphasic pattern of drug release and exhibited time-dependent and capacity-limited
bioactivity. Overall, SLMs containing 2 % w/w SRMS, 3 % w/w gentamicin and PEG 4000 entrapped
the highest amount of drug, released 99 % of drug and gave the highest inhibitory zone diameter (IZD)
against the organisms within 420 min, while plain gentamicin gave the least.
Conclusion: SRMS-based SLMs prepared with homolipid from
Capra hircus offers a suitable delivery
system for gentamicin.
