Noha M. Zaki
Nutraceuticals have always been considered as natural and safe supplements that may prevent disease, may substitute prescription drugs, may compensate for a poor diet or promote health. Several nutraceuticals products are in the market at present most of which are antioxidants and probiotics. The majority of nutraceutical products are intended for oral administration however; concerns related to their formulation, bioavailability and/or their site specific delivery arise. The labile nature, oral absorption and target-ability are the major underlying causes for poor nutraceuticals oral delivery. Investigators attempted to circumvent these obstacles by wide spectrum approaches tailored for each specific nutraceutical with solubility-enhancement techniques being the most commonly tackled. Recently, nanosizing techniques are utilized to answer the problem of nutraceuticals delivery with promising results in terms of nutraceutical-protection and stability on shelf and in vivo, solubility and dissolution rate enhancement, intestinal permeability improvement, intracellular and subcellular organelle targeting as well as extended circulation half-life all of which result in boosted bioavailability. The present review elucidates the progress and problems in the oral delivery of nutraceuticals.