The Protein Encapsulation in the Modified Chitosan Self-Aggregated Nanoparticles

Pharmaceutical drugs, such as proteins and peptides are well known as a new generation of drugs. However, the delivery of proteins and peptides in the body is limited by their specific physicochemical properties such as complex structure and high molecular weight. Encapsulation is an excellent method to the efficiently delivery of the proteins and peptides. Chitosan nanoparticles, with the ability to trap proteins in a hydrated polymer-network and minimize the protein fluctuations, are widely used as a drug delivery substance. In this study, we have evaluated the mechanisms of interactions between cholesterol-modified chitosan self-aggregated nanoparticles and human growth hormone (hGH) and follicle stimulating hormone (FSH) by using circular dichroism (CD), fluorescence, UV–vis absorption spectroscopy and molecular dynamics (MD) simulation. The fluorescence intensity of the proteins has indicated that the emission intensity increased with increasing of the nanoparticles concentration. The CD data have also revealed that the secondary structure of the proteins have not changed so much in the presence and absence of nanoparticles. The MD results have confirmed that the hormones backbone remained practically unchanged along MD simulations. According to previous studies and our results, the number of the cholesterol molecules per chitosan is critical for efficient performance. Our results have demonstrated that the protein molecules can be loaded on the cholesterol-modified chitosan self-aggregated nanoparticles and the mechanisms have been suggested to be regulated by several factors such as hydrogen bonding, hydrophobic, and electrostatic interactions. This study suggests that the cholesterol-modified chitosan self-aggregated nanoparticles can be useful as a carrier for protein drugs in the fields of nanomedicine and nanobiotechnology sciences.

کلیدواژه ها:

Human growth hormone ، Follicle stimulating hormone ، Drug delivery ، Nanobiotechnology ، Interactions