Background: Silk fibroin is the main protein of silk, and it has recently been evaluated for
drug delivery applications due to its excellent properties. Specifically, silk fibroin exhibits good biocompatibility,
biodegradability and low immunogenicity. Fibroin nanoparticles have attracted attention
due to their high binding ability to different drugs as well as their ability for controlled drug release.
The improvement of the therapeutic efficiency of drug encapsulation is important and depends
on the particle size, the chemical structure and the properties of the silk fibroin nanoparticles.
Methods: There is a variety of methods for the preparation of fibroin nanoparticles such as (i) electrospraying
and desolvation method, (ii) supercritical fluid technologies, (iii) capillary-microdot technique,
(iv) salting out etc. Furthermore, various techniques have been used for the characterization of
nanoparticles such as SEM (scanning electron microscopy), TEM (transmission electron microscopy),
DLS (dynamic light scattering), Zeta-potential and FTIR (Fourier transform infrared spectroscopy).
Different drugs (paclitaxel, curcumin, 5-fluorouracil etc) have been encapsulated in fibroin nanoparticles.
Results: Each separated synthesis method has different advantages such as (i) high yield, (ii) avoid use
of toxic solvents, (iii) low cost, (iv) controllable particle size, (v) no organic solvent residue, (vi) simplicity
of operation, (vii) small particles size, (viii) homeliness of operation, (ix) restrainable particle
size, (x) easy and safe to operate, (xi) no use of organic solvent. Moreover, some major drugs studied
are Floxuridine, Fluorouracil, Curcumin, Doxorubicin, Metotrexate, Paclitaxel, Doxorubicin, Horseradish
peroxidase. All the above combinations (preparation method-drug) are studied in detail.
Conclusion: Various drugs have been encapsulated successfully in silk fibroin and all of them exhibit
a significant release rate. Finally, the encapsulation efficiency and release rate depend on the molecular
weight of the drugs and it can be adjusted by controlling the crystallinity and concentration of silk