1. Date of download: 5/28/2016 Copyright © 2016 SPIE. All rights reserved. (a) A stack of representative three-dimensional images of 80-nm AuNPs embedded into one A549 cell after 24-h incubation. A cross- section view (left bottom) and its two corresponding longitudinal section views (left top and right bottom) are displayed. (b) A comparison of the proportion of particles localized in cell membrane relative to the total cell during different periods of incubation time. Figure Legend: From: Quantitative evaluation and visualization of size effect on cellular uptake of gold nanoparticles by multiphoton imaging-UV/Vis spectroscopic analysis J. Biomed. Opt. 2014;19(10):101505. doi:10.1117/1.JBO.19.10.101505

2. Date of download: 5/28/2016 Copyright © 2016 SPIE. All rights reserved. Intensity distribution in each threshold regime of gold nanoparticles (AuNPs) with size of (a) 15 nm, 30 nm, (b) 50 nm and 80 nm. Figure Legend: From: Quantitative evaluation and visualization of size effect on cellular uptake of gold nanoparticles by multiphoton imaging-UV/Vis spectroscopic analysis J. Biomed. Opt. 2014;19(10):101505. doi:10.1117/1.JBO.19.10.101505

3. Date of download: 5/28/2016 Copyright © 2016 SPIE. All rights reserved. (a) to (d) Confocal laser scanning microscopy (CLSM) and multiphoton laser scanning microscopy (MP-LSM) images of AuNPs with sizes of 15, 30, 50, and 80 nm, respectively, after incubation of A549 cells for 24 h. Green color represents cell membrane stained with DiI (confocal images) and red color spots represent AuNPs (MP images). Laser wavelength for excitation of AuNPs is optimized to λem=778 nm. The number concentration of various-sized AuNPs exposure to A549 cells was set to 7.5×1010 particles/mL. (e) The bar graph shows the amount of nonagglomerated AuNPs per optical stack versus nanoparticles size. The number of AuNPs with all sizes applied in each plate was 3.75×1010 particles. Figure Legend: From: Quantitative evaluation and visualization of size effect on cellular uptake of gold nanoparticles by multiphoton imaging-UV/Vis spectroscopic analysis J. Biomed. Opt. 2014;19(10):101505. doi:10.1117/1.JBO.19.10.101505

4. Date of download: 5/28/2016 Copyright © 2016 SPIE. All rights reserved. Quantitative evaluation of cellular uptake extent of AuNPs with sizes of (a) 15 nm, (b) 30 nm, (c) 50 nm, and (d) 80 nm in different time points by MP-LSM analysis. Figure Legend: From: Quantitative evaluation and visualization of size effect on cellular uptake of gold nanoparticles by multiphoton imaging-UV/Vis spectroscopic analysis J. Biomed. Opt. 2014;19(10):101505. doi:10.1117/1.JBO.19.10.101505

5. Date of download: 5/28/2016 Copyright © 2016 SPIE. All rights reserved. UV/Vis spectra of different-sized AuNPs. The concentrations of particles (based on particle number) before incubation with the cells are (a) 5.8×1011 particles/ml (15-nm AuNPs); (b) 1.36×1011 particles/ml (30-nm AuNPs); (c) 3.0×1010 particles/ml (50-nm AuNPs); and (d) 4.4×109 particles/ml (80-nm AuNPs). After 24-h incubation with cells, the maximum peak intensities of AuNPs decreased relative to those of before incubation, indicating uptake of AuNPs by cells during incubation. Figure Legend: From: Quantitative evaluation and visualization of size effect on cellular uptake of gold nanoparticles by multiphoton imaging-UV/Vis spectroscopic analysis J. Biomed. Opt. 2014;19(10):101505. doi:10.1117/1.JBO.19.10.101505

6. Date of download: 5/28/2016 Copyright © 2016 SPIE. All rights reserved. Quantification of the uptake percentage of AuNPs into cells relative to the total amount of particles applied per well at different time points by UV/Vis analysis. The initial gold amounts applied per cell growth well are (a) 2.9×1011 particles (15-nm AuNPs); (b) 6.8×1010 particles (30-nm AuNPs); (c) 1.5×1010 particles (50-nm AuNPs); and (d) 2.2×109 particles (80-nm AuNPs). A549 cells were incubated with different-sized AuNPs at 37°C with defined concentration mentioned above, and at each time point, the suspension medium was collected and analyzed for gold concentration by UV/Vis. Figure Legend: From: Quantitative evaluation and visualization of size effect on cellular uptake of gold nanoparticles by multiphoton imaging-UV/Vis spectroscopic analysis J. Biomed. Opt. 2014;19(10):101505. doi:10.1117/1.JBO.19.10.101505

7. Date of download: 5/28/2016 Copyright © 2016 SPIE. All rights reserved. Representation of the cellular uptake process of colloidal gold. The uptake extent is determined by particles concentration in contact zone, which highly depends on the sedimentation and diffusion velocity of AuNPs. Figure Legend: From: Quantitative evaluation and visualization of size effect on cellular uptake of gold nanoparticles by multiphoton imaging-UV/Vis spectroscopic analysis J. Biomed. Opt. 2014;19(10):101505. doi:10.1117/1.JBO.19.10.101505

8. Date of download: 5/28/2016 Copyright © 2016 SPIE. All rights reserved. Sedimentation effects of 15-, 30-, 50-, and 80-nm AuNPs at a series of time points from 0 to 48 h in cell grow medium. Figure Legend: From: Quantitative evaluation and visualization of size effect on cellular uptake of gold nanoparticles by multiphoton imaging-UV/Vis spectroscopic analysis J. Biomed. Opt. 2014;19(10):101505. doi:10.1117/1.JBO.19.10.101505