Table 1.

Summary of Protein Delivery Systems.

Strategies for Protein Delivery
Pegylation	This strategy consists in the conjugation of polymeric chains on protein surface. This allow increase significally the times of circulation of proteins in bloodstream, however has a limited efficacy to protect against proteases attack.
Liposomes	Liposomes are biocompatible and cell-like nanodevices. Proteins can be delivered inside the aqueous core of liposomes or attached on their surface. Liposomes are characterized by high flexibility but their use are limited by small stability in human body.
Inorganic nanoparticles	Mesoporous silica nanoparticles, gold nanoparticles and carbon nanotubes allow the delivery of proteins on their surface or inside them. They are characterized by a high sturdiness but have a poor flexibility.
Polymeric nanocapsules	This strategy consist in a polymerization in situ around the protein making a polymeric coating. This strategy can be used to a large number of proteins and allow the design of nanocapsules both degradable and non-degradable. This class of systems combine the sturdiness of inorganic nanoparticles with flexibility of liposomes