pravastatin transdermal patch: effect of the formulation and length of microneedles on in- vitro percutaneous absorption studies.

Transdermal patches loaded with pravastatin was previously characterized in another published study by serrano-castañeda et al; 2015. these transdermal patches (tp) were generated by the plate casting technique, the in-vitro percutaneous absorption studies of tp were evaluated for three different formulations with different quantities of pluronic f-127 (pf-127): i) without pf-127 (tp w), ii) 1% of pf-127 (tp 1%), and iii) 3% of pf-127 (tp 3%) using solid microneedles as a penetration enhancer with two different lengths: i) 0.25 mm and ii) 2.25 mm and iii) in-vitro permeation studies by passive diffusion. the fluxes (f), time lag (tlag) and permeability constants (kp) for each formulation were: tp w (f:38.5μg/cm²*h, tlag:18.97h and kp:5.9x10-3 cm/h), tp w with microneedles of 0.25 mm (f:103.3 μg/cm²*h, tlag: 20.76 h and kp: 0.0158 cm/h), tp w and microneedles of 2.25 mm (f:105.2μg/cm²*h, tlag: 21.16 h and kp: 0.0159cm/h), tp 1% (f:90 μg/cm²*h, tlag: 19.48 h and kp: 0.0137 cm/h), tp 1% with microneedles of 0.25 mm (f:111.4μg/cm2*h, tlag:19.11h and kp:0.017cm/h), and tp 1% with microneedles of 2.25 mm (f:115.2μg/cm²*h, tlag:16.73h and kp:0.017cm/h), tp 3% (f:40.9μg/cm²*h, tlag:20.45h and kp:0.0062 cm/h), tp 3% with microneedles of 0.25 mm (f:67.1 μg/cm²*h, tlag: 21.79h and kp:0.0102cm/h) and tp 3% with microneedles of 2.25 (f:70.5 μg/cm²*h, tlag:20.44h and kp:0.0107cm/h). results show that the formulation of tp affects the pravastatina flux and kp parameters, however the length of microneedles only has important effect on tlag.