Self-Assembled Chitosan Nanoparticles for Percutaneous Delivery of Caffeine: Preparation, Characterization, and In Vitro Release Studies

The study from 2018 focused on optimizing chitosan (CS)-tripolyphosphate (TPP) nanoparticles (NPs) for the enhanced percutaneous delivery of caffeine. Researchers found that the preparation conditions, including the CS:TPP volume ratio, drug concentration, and stirring speed, significantly affected the nanoparticles' size, charge, and uniformity. The optimal nanoparticles had a mean size of 143.43 nm, a zeta potential of +43.13 mV, and a polydispersity index of 0.30. The encapsulation efficiency and loading capacity for caffeine were 60.69% and 48.89%, respectively. In vitro release studies indicated that 58.7% of caffeine was released from the nanoparticles after 72 hours, which was higher than the control's 41.5%. Stability tests showed that the nanoparticles were more stable at 4 °C than at 25 °C and that freeze-dried nanoparticles were unstable. The study, with a sample size of n=3 for each test, concluded that CS-TPP-NPs have potential as a delivery system for sustained release of caffeine, which could be beneficial for treating conditions like androgenic alopecia.