Biopharmaceuticals are a generation of drugs that include peptides, proteins,
nucleic acids and cell products. According to their particular molecular characteristics
(e.g. high molecular size, susceptibility to enzymatic activity), these products present
some limitations for administration and usually parenteral routes are the only option. To avoid these limitations, different
colloidal carriers (e.g. liposomes, micelles, microemulsions and dendrimers) have been proposed to improve biopharmaceuticals
delivery. Liposomes are promising drug delivery systems, despite some limitations have been reported (e.g.
in vivo failure, poor long-term stability and low transfection efficiency), and only a limited number of formulations have
reached the market. Micelles and microemulsions require more studies to exclude some of the observed drawbacks and
guarantee their potential for use in clinic. According to their peculiar structures, dendrimers have been showing good results
for nucleic acids delivery and a great development of these systems during next years is expected. This is the Part II
of two review articles, which provides the state of the art of biopharmaceuticals delivery systems. Part II deals with
liposomes, micelles, microemulsions and dendrimers.