Reactions of dipolar bio-molecules in nano-capsules — example of folding-unfolding process

The confinement of chemical reactions in nano-capsules can lead to a dramatic effect on the equilibrium constant of these latter. Indeed, capillary effects due to the curvature and surface energy of nano-capsules can alter in a noticeable way the evolution of reactions occurring within.Nano-encapsulation of bio-materials has attracted lately wide interest from the scientific community because of the great potential of its applications in biomedical areas and targeted therapies.The present paper focuses one's attention on alterations of conformation mechanisms due to extremely confining and interacting solvated dipolar macromolecules at their isoelectric point. As a specific example studied here, the folding–unfolding reaction of proteins (particularly RNase A and creatine kinase CK) is drastically changed when encapsulated in solid inorganic hollow nano-capsules.The effects demonstrated in this work can be extended to a wide variety of nano-encapsulation situations. The design and sizing of nano-capsules can even make use of the effects shown in the present study to achieve better and more effective encapsulation.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Nano-encapsulation is considered as a promising technique for new therapies. ► The nano-capsules material and size can drastically affect reactions within. ► Capilllary pressure alters equilibrium and kinetic constants inside nano-capsules. ► Dipolar interactions also alter protein unfolding kinetics in metal nano-capsules. ► Nano-encapsulation for bio-medical applications can exploit these effects.