Monodisperse aqueous microspheres encapsulating high concentration of l-ascorbic acid: insights of preparation and stability evaluation from straight-through microchannel emulsification.
Stabilization of l-ascorbic acid (l-AA) is a challenging task for food and pharmaceutical industries. The study was conducted to prepare monodisperse aqueous microspheres containing enhanced concentrations of l-AA by using microchannel emulsification (MCE). The asymmetric straight-through microchannel (MC) array used here constitutes 11 × 104 μm microslots connected to a 10 μm circular microholes. 5-30% (w/w) l-AA was added to a Milli-Q water solution containing 2% (w/w) sodium alginate and 1% (w/w) magnesium sulfate, while the continuous phase constitutes 5% (w/w) tetraglycerol condensed ricinoleate in water-saturated decane. Monodisperse aqueous microspheres with average diameters (dav) of 18.7-20.7 μm and coefficients of variation (CVs) below 6% were successfully prepared via MCE regardless of the l-AA concentrations applied. The collected microspheres were physically stable in terms of their dav and CV for >10 days of storage at 40°C. The aqueous microspheres exhibited l-AA encapsulation efficiency exceeding 70% during the storage.
['Khalid|Nauman|N|', 'Kobayashi|Isao|I|', 'Neves|Marcos A|MA|', 'Uemura|Kunihiko|K|', 'Nakajima|Mitsutoshi|M|', 'Nabetani|Hiroshi|H|']
D000464:Alginates D001205:Ascorbic Acid D004339:Drug Compounding D004655:Emulsions D019649:Food Industry D020723:Glucuronic Acid D006603:Hexuronic Acids D008863:Microspheres D010316:Particle Size D014867:Water
high concentration l-ascorbic acid stability sodium alginate monodisperse microspheres