The development of microcapsules using combined alginate-chitosan technology

Introduction. Microencapsulation techniques often use a single encapsulating material; however, combining materials such as sodium alginate and chitosan can enhance their individual properties by complementing each other’s characteristics [1]. In this study, the technique is applied to encapsulate the emulsion of Artemisia annua L. extract and cannabis seed oil, rich in flavonoids, terpenes and cannabinoids, which are recognized for their potential cancer preventing effects [2,3]. Aim of the study. To determine the optimal alginate-chitosan ratio for producing microcapsules with superior physical characteristics. Research methods. The Artemisia annua L extract was prepared by using ultrasound-assisted extraction. The double W/O/W emulsion containing 16% (w/w) plant extract and 21% (w/w) cannabis seed oil was formulated using ultrasound and homogenization techniques. Emulsions were prepared with varying concentrations of sodium alginate (1%, 2% and 3%). A 2% CaCl2 crosslink solution was mixed with 1% neutralized chitosan (pH 6,5). The emulsion was extruded at 0,05 ml/min flow rate and stirred at 400 rpm for 15 min. 10 samples of microcapsules were subjected to encapsulation yield, compression, moisture and particle size analyses. Main results. The moisture content of the microcapsules ranged from 11.0 ± 0.5% to 31.9 ± 1.9%, with the highest observed in 1% alginate microcapsules and the lowest in 3% alginate. Microcapsules containing 2% alginate exhibited the strongest compressibility resistance, with a hardness of 3195 ± 178 g, followed by 3 % alginate (2582 ± 148 g) and 1% alginate which demonstrated the weakest resistance (448 ± 22 g). The 2% alginate microcapsules also exhibited the largest encapsulation yield (92.5 ± 0.4%) and the smallest size (1.46 ± 0.03 mm). Conclusions. Microcapsules with 2% alginate and 1% chitosan demonstrated optimal characteristics making them suitable for future research.