Encapsulation of Antitumor Drug Doxorubicin and Its Analogue by Chitosan Nanoparticles

• Published in: Biomacromolecules Vol. 14; no. 2; pp. 557 - 563
• Main Authors: Sanyakamdhorn, Sriwanna, Agudelo, Daniel, Tajmir-Riahi, Heidar-Ali
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 11.02.2013
• Subjects: Antibiotics, Antineoplastic - chemistry; Applied sciences; Biological and medical sciences; Chitosan - chemistry; Doxorubicin - analogs & derivatives; Doxorubicin - chemistry; Drug Carriers - chemistry; Exact sciences and technology; General pharmacology; Hydrogen Bonding; Hydrophobic and Hydrophilic Interactions; Medical sciences; Models, Molecular; Nanoparticles - chemistry; Natural polymers; Pharmaceutical technology. Pharmaceutical industry; Pharmacology. Drug treatments; Physicochemistry of polymers; Polymers - chemistry; Starch and polysaccharides; Antineoplastic agent; Complexation; Control release polymer; Drug carrier; Experimental study; Doxorubicin; Modeling; Intermolecular interaction; Molecular model; Binding mode; Oside polymer; Chitosan; Aqueous solution
• ISSN: 1525-7797; 1526-4602
• DOI: 10.1021/bm3018577

Biodegradable chitosan of different sizes were used to encapsulate antitumor drug doxorubicin (Dox) and its N-(trifluoroacetyl) doxorubicin (FDox) analogue. The complexation of Dox and FDox with chitosan 15, 100, and 200 KD was investigated in aqueous solution, using FTIR, fluorescence spectroscopic methods, and molecular modeling. The structural analysis showed that Dox and FDox bind chitosan via both hydrophilic and hydrophobic contacts with overall binding constants of K Dox‑ch‑15 = 8.4 (±0.6) × 103 M–1, K Dox‑ch‑100 = 2.2 (±0.3) × 105 M–1, K Dox‑ch‑200 = 3.7 (±0.5) × 104 M–1, K FDox‑ch‑15 = 5.5 (±0.5) × 103 M–1, K FDox‑ch‑100 = 6.8 (±0.6) × 104 M–1, and K FDox‑ch‑200 = 2.9 (±0.5) × 104 M–1, with the number of drug molecules bound per chitosan (n) ranging from 1.2 to 0.5. The order of binding is ch-100 > 200 > 15 KD, with stronger complexes formed with Dox than FDox. The molecular modeling showed the participation of polymer charged NH2 residues with drug OH and NH2 groups in the drug–polymer adducts. The presence of the hydrogen-bonding system in FDox-chitosan adducts stabilizes the drug–polymer complexation, with the free binding energy of −3.89 kcal/mol for Dox and −3.76 kcal/mol for FDox complexes. The results show chitosan 100 KD is a more suitable carrier for Dox and FDox delivery.