Overcoming poor oral bioavailability using nanoparticle formulations – opportunities and limitations

Oral delivery of drugs with poor aqueous solubility and poor enzymatic and/or metabolic stability is very challenging. However, the advent of nanotechnology has revolutionized the field of oral drug delivery. The review provides an overview of various nano-architectures such as nanosuspensions, lipid and polymeric nanocarriers, inorganic nanostructures and describes advantages and challenges associated with their efficient delivery. Among various nano-architectures, only nanosuspensions and spontaneously emulsifying systems have succeeded in reaching pharmaceutical market.