1. Department of Chemistry, Faculty of ScienceChulalongkorn University, Phayathai Rd. Pathumwan Bangkok 10300 Thailand
2. Nanotec-CU Center of Excellence on Food and AgricultureDepartment of Chemistry, Faculty of Science, Chulalongkorn University Bangkok 10330 Thailand
3. National Nanotechnology Center, NSTDA, 111 Thailand Science Park, Klong Luang Pathum Thani 12120 Thailand