Efektivitas ekstrak centella asiatica dalam nanopartikel kitosan terhadap aktivitas proliferasi sel fibroblas dan keratinosit sintesis kolagen I, III dan ekspresi protein aquaporin-3 secara in vitro = The Effectiveness of centella asiatica in chitosan nanoparticles to the activity of cell proliferation collagen synthesis I,III and protein expression of aquaporin-3 in vitro