Encapsulation of Menthol in Beeswax by a Supercritical Fluid Technique

Abstract

Encapsulation of menthol in beeswax was prepared by a modified particles from gas-saturated solutions (PGSS) process with controlling the gas-saturated solution flow rate. Menthol/beeswax particles with size in the range of 2-50 μm were produced. The effects of the process conditions, namely, the pre-expansion pressure, pre-expansion temperature, gas-saturated solution flow rate, and menthol composition, on the particle size, particle size distribution, and menthol encapsulation rate were investigated. Results indicated that in the range of studied conditions, increase of the pressure, decrease of the gas-saturated solution flow rate, and decrease of the menthol mass fraction can decrease the particle size and narrow particle size distribution of the produced menthol/beeswax microparticles. An N 2 -blowing method was proposed to measure the menthol release from the menthol/beeswax microparticles. Results showed that the microparticles have obvious protection of menthol from its volatilization loss.

Natural Polymers in Micro- and Nanoencapsulation for Therapeutic and Diagnostic Applications: Part I: Lipids and Fabrication Techniques

“…The resulting saturated solution is rapidly expanded through a tiny nozzle using moderate pressure which leads to reduction in temperature and the formation of particles due to the cooling effect. Zhu and colleagues [87] encapsulated menthol in beeswax using the PGSS.…”

Characteristics of lipid micro- and nanoparticles based on supercritical formation for potential pharmaceutical application

“…Equipped with an 80-μm-diameter nozzle and under the same pre-expansion conditions, the same authors showed less attractive results from lipid particles synthesized with beeswax and menthol. A multimodal population of particles ranging from 45 to 180 μm was obtained [ 100 ]. By application of similar conditions, Sampaio de Sousa and colleagues [ 62 ] achieved glyceryl monostearate microparticles of about 5 μm loaded with caffeine, though, owing to the hydrophilicity of caffeine, it was necessary to use water as co-solvent.…”

Precise size‐controllable generation of alginate encapsulated menthol microcapsules by active flow‐focusing microfluidic technology

“…7,8 However, spray-dried microcapsules tend to have a wide particle size distribution and a high surface drug residue rate, which limits their practical application. In addition to the two aforementioned methods, Lan et al 9 encapsulated menthol by beeswax using a supercritical fluid approach. The as-prepared menthol/beeswax microcapsules protected menthol from volatilization loss.…”