Release of folic acid from sodium alginate-pectin-poly(ethylene oxide) electrospun fibers under in vitro conditions

- Folic acid was encapsulated in electrospun alginate-pectin fibers.
- In water, the release of folic acid was significant lower at pH 3 than at pH 7.8.
- Limited folic acid release was observed in simulated gastric fluid.
- Folic acid release rates were different in water and simulated intestinal fluid.
- Electrospun alginate-pectin fibers are promising carrier for delivering folic acid.

The present study evaluated the release behavior of folic acid from ultrafine sodium alginate-pectin-poly(ethylene oxide) electrospun fibers under in vitro conditions. In aqueous solution, the release of folic acid at pH 1.2 (64%) was significantly higher than at pH 3 (21%). At pH 7.8, the majority of folic acid was released (97%) due to extensive swelling and partial dissolution of the fibers. In simulated gastric juice, the folic acid release profile was similar to that of aqueous solution at pH 1.2. By contrast, using the simulated pH 7.8 intestinal fluid, a lower amount (40%) of folic acid was released as compared with the aqueous alkaline solution. These results showed that the release of folic acid from the alginate fibers is affected by the constituents present in the simulated intestinal fluid, in addition to the pH effect. The in vitro release study showed that the composite alginate electrospun fibers have good potential as a carrier that retains folic acid in acidic food products (pH 3), but selectively releases the micronutrient in the small intestine.