1. Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, School of Biomedical Engineering, Health Science Center, Shenzhen University, Shenzhen 518060, China
2. School of Electrical and Electronic Engineering, Nanyang Technological University, 639798 Singapore
3. Departments of Chemistry and Chemical Engineering, National University of Singapore, 119077 Singapore
4. School of Biomedical Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia
5. The University of Sydney Nano Institute, The University of Sydney, Sydney, New South Wales 2006, Australia