Holographic Characterization of Protein Aggregates Size, morphology and differentiation … one particle at a time (and fast) D. G. Grier, C. Wang, X. Zhong, & M. D. Ward New York University D. B. Ruffner & L. A. Philips Spheryx, Inc
Holographic Characterization Particle-resolved measurements of Radius: subvisible range 200 nm to 10 m m Refractive index: proxy for composition Useful for differentiation Morphology Useful for differentiation Useful for analyzing aggregation mechanism Concentration Divide observed counts by measured sample volume Real-time processes 30 measurements/second Complete analysis in 10 minutes 2 2016 UMB-CERSI
So, what’s the problem? 3 2016 UMB-CERSI
Conventional Characterization (DLS) 40 PDMS spheres in water 0 500 1000 Malvern Zetasizer Nano ZS 4 2016 UMB-CERSI
Holographic Characterization 1.42 1.0 Relative Probability 1.41 Refractive Index 1.40 0.5 1.39 5,000 spheres one sphere 1.38 1.37 0 0.4 0.6 0.8 1.0 1.2 Radius Wang, et al. , Soft Matter 11 , 1062 (2015) 5 2016 UMB-CERSI
Holographic Tracking & Characterization Lorenz-Mie Microscopy Parameters 3D Position 𝒔 𝑞 (𝑢) Tracking 𝑏 𝑞 Radius Characterization Refractive Index 𝑜 𝑞 Lee et al. , Optics Express 15 , 18275 (2007) 6 2016 UMB-CERSI
Holographic Tracking & Characterization How Lorenz-Mie Microscopy works Incident plane wave: Scattered field: : position : radius : refractive index Focal plane Lee et al. , Optics Express 15 , 18275 (2007) 7 2016 UMB-CERSI
Holographic Tracking & Characterization How Lorenz-Mie Microscopy works Lee et al. , Optics Express 15 , 18275 (2007) 8 2016 UMB-CERSI
Holographic Tracking & Characterization How Lorenz-Mie Microscopy works Lorenz-Mie scattering coefficients for a sphere: • relative radius: • refractive index: Lee et al. , Optics Express 15 , 18275 (2007) 9 2016 UMB-CERSI
Lorenz-Mie Microscopy Lee et al. , Optics Express 15 , 18275 (2007) 10 2016 UMB-CERSI
Holographic Tracking & Characterization Independently verified performance Property Precision Range 100 × 100 × 100 𝜈 m 3 Δ𝒔 𝑞 ≤ 3 nm 3D Position Radius Δ𝑏 𝑞 ≤ 2 nm 200 nm − 20 𝜈 m Δ𝑜 𝑞 ≤ 10 −3 Refractive Index 1 − 5 10 3 mL −1 − 10 8 mL −1 Δ𝑑 𝑞 ≈ 𝑑 𝑞 Concentration NIST Traceable Particles 𝑒 𝑞 = 2 𝑏 𝑞 = 1.54 ± 0.05 𝜈 m 𝑜 𝑞 = 1.598 ± 0.005 Bangs Labs #12035 Krishnatreya et al. , Am. J. Phys. 82 , 23 (2014) 11 2016 UMB-CERSI
Holographic Tracking & Characterization Independently verified performance Property Precision Range 100 × 100 × 100 𝜈 m 3 Δ𝒔 𝑞 ≤ 3 nm 3D Position Radius Δ𝑏 𝑞 ≤ 2 nm 200 nm − 20 𝜈 m Δ𝑜 𝑞 ≤ 10 −3 Refractive Index 1 − 5 10 3 mL −1 − 10 7 mL −1 Δ𝑑 𝑞 ≈ 𝑑 𝑞 Concentration NIST traceable PS Measured flow volume (no calibration) Krishnatreya et al. , Am. J. Phys. 82 , 23 (2014) 12 2016 UMB-CERSI
Automated Holographic Characterization 1. Particles pass through laser beam in microfluidic channel 3. Compare measurement to scattering theory 2. Microscope records interference pattern 4. Comparison yields 5. Build statistics: : radius Each point : refractive index characterizes : 3D position one particle Size/refractive index distribution: for 2,500 spheres acquired in 10 minutes 13 2016 UMB-CERSI
Characterizing Colloidal Mixtures silica polystyrene Yevick, Hannel & Grier, Optics Express 22 , 22864 (2014) 14 2016 UMB-CERSI
Characterizing Protein Aggregates BSA in Tris + added salt Wang et al. , J. Pharm. Sci. 105 , 1074 (2016) 15 2016 UMB-CERSI
Differentiating Silicone Oil Droplets Wang et al. , J. Pharm. Sci. 105 , 1074 (2016) 16 2016 UMB-CERSI
Characterizing Protein & Contaminants Wang et al. , J. Pharm. Sci. 105 , 1074 (2016) 17 2016 UMB-CERSI
Effective Medium Theory Porous particle Material: Refractive index: Volume fraction: Medium: Refractive index: Effective refractive index: Lorentz-Lorenz factor: Cheong et al. , Soft Matter 7 , 6816 (2011) 18 2016 UMB-CERSI
Fractal Aggregates Volume fraction: Effective Medium Theory: Size-Index Scaling: Wang et al. , Soft Matter 12 , 8774 (2016) 19 2016 UMB-CERSI
Fractal Scaling of Protein Aggregates Bovine Serum Albumin Bovine Insulin Filamentary clusters Cluster-cluster aggregates Wang et al. , Soft Matter 12 , 8774 (2016) 20 2016 UMB-CERSI
Holographic Characterization of Human IgG 10 -1 10 -2 10 -3 silicone 10 -4 1 10 1 10 Large fractal dimension: compact clusters Differentiation between protein aggregates and silicone droplets Ruffner et al. , unpublished (2016) 21 2016 UMB-CERSI
Holographic Characterization Detects, counts and characterizes subvisible protein aggregates in situ Differentiates by composition & morphology Fast, time-resolved measurements Independently verified precision & accuracy Minimal calibration 22 2016 UMB-CERSI
23 2016 UMB-CERSI
Comparison with Industry Standard DLS (Malvern Zetasizer Nano) 1. Consistent mean radius results in common range 2. HVM also works for larger particles 3. HVM results have smaller (better) instrumental spread 4. HVM also yields refractive index (porosity) Cheong et al. , Opt. Express 17 , 13071 (2009) Cheong, Xiao, Pine & Grier, Soft Matter 7 , 6816 (2011) 24 2016 UMB-CERSI
So, what do our clusters look like? hologram fit 25 2016 UMB-CERSI
So, what do our clusters look like? hologram fit Holographic Deconvolution Microscopy Dixon et al., Opt. Express 19 , 16410 (2011) Chen et al. , J. Pharm. Sci. 105 , 1074 (2016) 26 2016 UMB-CERSI
So, what do our clusters look like? hologram fit 27 2016 UMB-CERSI
So, what do our clusters look like? hologram fit 28 2016 UMB-CERSI
So, what do our clusters look like? hologram fit 29 2016 UMB-CERSI
Recommend
More recommend