The hydrophilic peptide YY (PYY)
is a promising hormone-based antiobesity
drug. We present a new concept for the delivery of PYY from pH-responsive
chitosan-based nanocarriers. To overcome the drawbacks while retaining
the merits of the polyelectrolyte complex (PEC) method, we propose
a one-pot approach for the encapsulation of a hydrophilic peptide
drug in cross-linked PEC nanocarriers. First, the hydrophilic peptide
is encapsulated via polyelectrolyte complexation within water-in-oil
miniemulsion droplets. In a second step, the PEC surface is reinforced
by controlled interfacial cross-linking. PYY is efficiently encapsulated
and released upon pH change. Such nanocarriers are promising candidates
for the fight against obesity and, in general, for the oral delivery
of protein drugs
