1. Healthy Medical Engineering Technology Research Center, Guangdong Food and Drug Vocational College, Guangzhou 510520, P. R. China
2. MOE Key Laboratory of Laser Life Science & SATCM Third Grade Laboratory of Chinese Medicine and Photonics Technology, College of Biophotonics, South China Normal University, Guangzhou 510631, P. R. China
3. College of Materials and Energy, South China Agricultural University, Guangzhou 510642, P. R. China