Targeted Delivery of Chemotherapeutic Agents Using Improved Radiosensitive Liquid Core Microcapsules and Assessment of Their Antitumor Effect
- Department of Radiology, Iwate Medical University, Morioka (Japan)
- Department of Quantum Science and Energy Engineering, Tohoku University, Sendai (Japan)
- Takasaki Institute of the Radiation Chemistry Research Establishment, Japan Atomic Energy Research Institute, Takasaki (Japan)
- Cyclotron Center of Iwate Medical University, Iwate (Japan)
- Nishina Memorial Cyclotron Center, Japan Radioisotope Association, Takizawa (Japan)
Purpose: Radiation-sensitive microcapsules composed of alginate and hyaluronic acid are being developed. We report the development of improved microcapsules that were prepared using calcium- and yttrium-induced polymerization. We previously reported on the combined antitumor effect of carboplatin-containing microcapsules and radiotherapy. Methods and Materials: We mixed a 0.1% (wt/vol) solution of hyaluronic acid with a 0.2% alginate solution. Carboplatin (l mg) and indocyanine green (12.5 {mu}g) were added to this mixture, and the resultant material was used for capsule preparation. The capsules were prepared by spraying the material into a mixture containing a 4.34% CaCl{sub 2} solution supplemented with 0-0.01% yttrium. These capsules were irradiated with single doses of 0.5, 1.0, 1.5, or 2 Gy {sup 60}Co {gamma}-rays. Immediately after irradiation, the frequency of microcapsule decomposition was determined using a microparticle-induced X-ray emission camera. The amount of core content released was estimated by particle-induced X-ray emission and colorimetric analysis with 0.25% indocyanine green. The antitumor effect of the combined therapy was determined by monitoring its effects on the diameter of an inoculated Meth A fibrosarcoma. Results: Microcapsules that had been polymerized using a 4.34% CaCl{sub 2} solution supplemented with 5.0 x 10{sup -3}% (10{sup -3}% meant or 10%{sup -3}) yttrium exhibited the maximal decomposition, and the optimal release of core content occurred after 2-Gy irradiation. The microcapsules exhibited a synergistic antitumor effect combined with 2-Gy irradiation and were associated with reduced adverse effects. Conclusion: The results of our study have shown that our liquid core microcapsules can be used in radiotherapy for targeted delivery of chemotherapeutic agents.
- OSTI ID:
- 21282047
- Journal Information:
- International Journal of Radiation Oncology, Biology and Physics, Journal Name: International Journal of Radiation Oncology, Biology and Physics Journal Issue: 2 Vol. 75; ISSN IOBPD3; ISSN 0360-3016
- Country of Publication:
- United States
- Language:
- English
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