The Milling Method in Formation of Inclusion Complex p-Methoxycinnamic Acid-Hydroxypropyl-β-Cyclodextrin

p-methoxycinnamic acid (pMCA) is a substance with several pharmacological activities, derived from the rhizome of Kaempferia galanga Linn. The solubility of pMCA can be increased by the formation of inclusion complexes (IC) using hydroxypropyl-β-cyclodextrin (HPβCD) compounds. IC are obtained through the milling method, which is a simple, environmentally friendly, and low-cost manufacturing method. The process involves the pounding of material with a certain speed and impact force. This research aims to characterize the pMCA-HPβCD IC made using the milling method. Milling the mixture of pMCA and HPβCD using a ball mill is a common technique to enhance the formation of the inclusion complex. The IC’s physical characteristics were analyzed in terms of their morphology, particle size, crystallinity, and thermal properties. The dissolution profile was also performed using paddle-typed dissolution apparatus (Type II) with 500 mL distilled water as dissolution medium. The amount of pMCA dissolved was determined using UV spectrophotometry. The dissolution parameter was determined as dissolution efficiency at 60 minutes (DE₆₀). The IC particles were irregular in shapes and porous. The size was reduced as compared to the individual components. The XRD revealed that the ICs were amorphous. The DE₆₀ of IC increased by a factor of 4.3 compared to the pure pMCA. In conclusion, the milling method successfully formed complex of pMCA-HPβCD with different characteristics from the initial compound and was significantly increased the percentage of the dissolved pMCA.