The oral route is considered the most patient-convenient means of drug administration. In recent years there has been a tendency to employ smart carrier systems that enable controlled or timed release of a bioactive material, thereby providing a better dosing pattern and minimizing side effects. Nano-encapsulation systems (nanocarriers) offer important advantages over conventional drug delivery techniques. Nanocarriers can protect the drug from chemical/enzymatic degradation and enhance bioavailability. Prebiotics are ideal ingredients for the nano-encapsulation and oral drug delivery due to their natural ability to protect the encapsulated compound in the upper gasterointestinal (GI) tract. Here the potential of prebiotics for oral delivery of drugs and other bioactives is reviewed.
Nanoscale lipid bilayers, or nanoliposomes, are generally spherical vesicles formed by the dispersion of phospholipid molecules in a water-based medium by energy input. The other nanoscale object discussed in this entry, i.e., tocosome, is a recently introduced bioactive carrier made mainly from tocopheryl phosphates. Due to their bi-compartmental structure, which consists of lipidic and aqueous compartments, these nanocarriers are capable of carrying hydrophilic and hydrophobic material separately or simultaneously. Nanoliposomes and tocosomes are able to provide protection and release of sensitive food-grade bioactive materials in a sustained manner. They are being utilized for the encapsulation of different types of bioactive materials (such as drugs, vaccines, antimicrobials, antioxidants, minerals and preservatives), for the enrichment and fortification of different food and nutraceutical formulations and manufacturing of functional products. However, a number of issues unique to the nutraceutical and food industry must first be resolved before these applications can completely become a reality. Considering the potentials and promises of these colloidal carrier systems, the present article reviews various aspects of nanoliposomes, in comparison with tocosomes, including the ingredients used in their manufacture, formation mechanisms and issues pertaining to their application in the formulation of health promoting dietary supplements and functional food products.