Encapsulation of Frankincense Essential Oil by Microfluidic and Bulk Approaches: A Comparative Study

Herbs and hand-made herbal remedies have been long used for disease control, treatment, and health improvement. Evidence suggests that a single herb’s compounds can have synergistic functions with probably no adverse effect. Unfortunately, the traditional administration of essential oil (EO) does not follow a regulatory dose regimen, causing reduced bioavailability due to EO evaporation or denaturation in harsh biological environments. Hence, encapsulation can help enhance EO stability and dose dependence. Here, chitosan nanoparticles (ChNPs) were used to encapsulate frankincense essential oil (FEO) to preserve its remarkable therapeutic effects. Also, traditional bulk preparation methods were compared with microfluidic with central aqueous stream configuration (CAS). The results indicated the higher quality of microfluidic-based nanoparticles with uniform, spherical, and separated morphologies. The size of bulk and microfluidic nanoparticles ranged from 86 to 118 nm, the surface charge varied from 12.5 to 19.5 for different amounts of FEO, and the as-prepared colloid remained stable for three days. Narrow size distribution (PDI≤0.28) and high encapsulation efficiency (EE≤99 %) were achieved using the microfluidic process compared to the bulk method (PDI=0.74, EE≤90 %). The microfluidic nanoparticle also indicated a burst release rate greater than the bulk method (≤30 %). It was concluded that the high-performance microfluidic approach provided higher quality and more control over nanoparticle properties.