HT-DLS for Biotherapeutic and Nanoparticle Development
Speed up size and stability screening with high-throughput dynamic light scattering
Revolutionize your biotherapeutic and nanoparticle development with high- throughput dynamic light scattering (HT-DLS) and the automated DynaPro® Plate Reader II. The DynaPro excels at high-throughput sizing and screening of biopharmaceutical and nanoparticle formulations to enable novel workflows that simply would not be possible with other DLS instruments. Even if you need to run just a handful of samples, it's a great productivity booster.
Fully Automated DLS
The DynaPro Plate Reader II offers dynamic light scattering (DLS) measurements of the size and interactions of proteins, nanoparticles and other macromolecules in situ in industry-standard microwell plates. No liquid handling occurs after dispensing into the plates, to maximize throughput and minimize sample carryover. This ground-breaking instrument provides rapid optimization of formulations and process development for:
- Biotherapeutics such as monoclonal antibodies, insulin, virus-like particles (VLPs) and other parenteral biopharmaceuticals
- Nanoparticle drug delivery vehicles including liposomes, vaccines, and polymer micelles
- Nanosuspensions such as polymer-encapsulated peptide drug particles, emulsions and gold or magnetic nanoparticles
- Measure hydrodynamic radius from 0.5 nm to 1000 nm
- Sensitivity down to 0.125 mg/mL lysozyme
- Industry standard microwell plates of 96, 384 or 1536 wells
- All measurements made in situ in the wells
- Temperature ramps from 4°C to 85°C
- Integrates with plate-based liquid handling robotics
A wealth of applications
The DynaPro Plate Reader II provides unparalleled levels of ease-of-use, productivity, reproducibility, and flexibility in order to address additional demanding applications such as:
- Optimizing protein crystallization
- Assessing aggregation or oligomerization
- Quality control of proteins and nanoparticles
- Determining protein stability-indicating parameters such as thermal denaturation, chemical denaturation and colloidal stability through the diffusion interaction parameter kD
- Screening high-concentration protein solutions for reversible association and viscosity
A wealth of features
- Rapid or slow temperature ramps 4°C - 85°C with excellent uniformity across the plates. Samples are heated in parallel and all filled wells measured at each temperature
- Well read times as short as 5-10 seconds
- Integration with liquid-handling robots for higher levels of automation, especially when your workflow is plate-based, and utilizes spectroscopic and other plate readers in addition to DLS
- A camera for viewing each well from below, to aid in data diagnostics (e.g. to detect precipitation or bubble formation)
A set of images collected by the onboard camera, showing clean wells and wells containing bubbles, crystals and precipitates.
An OLE software API is available for interfacing the DynaPro Plate Reader II to robotic liquid handling in the high-throughput lab. This capability allows for fully automated plate loading and data collection.
Wyatt partners with several companies that offer integrated solutions for automated loading and analysis of plated samples:
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In addition, Hamilton Robotics, Caliper Life Sciences, and Tecan offer custom integration services.
How DLS Measures Size
Dynamic light scattering (DLS) takes advantage of Brownian motion to measure particle size. The smaller the particle, the higher its diffusion coefficient, and hence the more rapidly it jitters around in a liquid. The particles are illuminated with a laser beam to monitor their motion.
Each particle scatters light as it moves. Light waves from each particle in the detection volume will reach the detector and contribute to the scattering signal. However, the phase of each particle changes over time as the particles move randomly. The different phases may add constructively, producing a larger signal, or destructively producing a smaller signal. As particle diffuse randomly, the scattering signal fluctuates at a rate that may be directly tied to the diffusion coefficient.
A DLS detector incorporates a very fast detector that responds to the rapid signal fluctuations. The detector's electronics and the software work in combination to measure the rate of fluctuations and convert it to a measure of size known a the "hydrodynamic radius", Rh. In this manner DLS can measure the sizes over a large range covering peptides, proteins, viruses, lipsomes and other nanoparticles up to several microns in diameter
Size Distributions: When a solution contains a distribution of sizes, the scattering signal fluctuations reflect the various rates. The software can deconvolve the different diffusion coefficients to determine a size distribution. While DLS cannot resolve monomers from dimers or other small oligomers, it can distinguish between particles that vary in radius by 3-5x. The presence of large protein aggregates in a monomeric solution is readily determined, as is the presence of large micelles amongst monomeric peptides.
Viscosity: DLS measures viscosity of concentrated protein solutions using a probe particle of known size, such as a 100 nm polystyrene latex sphere. As the solution becomes viscous the probe diffuses more slowly. The software compares the measured diffusion coefficient with the known particle size to back out the viscosity.
Unfolding and Denaturation: DLS measures protein unfolding vs temperature (thermal denaturation) or vs. concentration of a denaturant such as urea or guanidine HCl (chemical denaturation) in order to assess protein stability. Unfolding is discriminated from aggregation by tracking the total scattering intensity:
- When no aggregation occurs, the total intensity remains constant even though the rate of diffusion changes.
- When unfolding is accompanied by aggregation, both the total intensity increase and the rate of diffusion changes.
Nanosolution Stability: DLS quantifies the stability of a nanoparticle in solution or nanosuspension by tracking the changes in size with time or temperature. Another possibility is to monitor aggregation at elevated temperature. The DynaPro supports all of these options.
Colloidal Stability: Attraction and repulsion between proteins or particles may be measured through the concentration dependence of the diffusion coefficient. This is quite easy to do in the DynaPro Plate Reader II, simply filling the wells with a series of concentrations and plotting the diffusion coefficient vs. concentration to determine the diffusion interaction parameter which is positive for stable solutions and negative for unstable solutions.
Supported Well Plate Formats 96, 384 or 1536 * Size Range (Radius, Rh) 0.5 to 1000 nm Minimum Concentration @ 14 kDa 0.125 mg/mL † Optics Laser Wavelength 830 nm Laser Power Control Programmable 10% – 100% Attenuation Range 1 to 106 Temperature Control 4 – 85°C †† Fluidics Minimum Sample Volume 4 µL ††† Data Acquisition Time 1 to 3600 seconds per well per read Read Time per Well 5 – 20 seconds Electronics Onboard Camera 3 megapixels †††† Digital Communication Ethernet (TCP/IP) Dimensions 60 cm (L) x 36 cm (W) x 25 cm (H)
† Minimum concentration specified with 50 µL of Lysozyme (14 kDa) sample in a 384 well plate, Wyatt P/N P8803-384, with 100 seconds acquisition.
†† Accuracy of ± 0.5°C for 4 – 50°C, and ± 1°C for 50 – 80°C. Minimum temperature of 4°C requires a laboratory temperature of 24°C or below.
††† Minimum volume specified with 2 mg/mL Lysozyme in a 1536 well plate, Wyatt P/N P8803-1536, with 25 seconds acquisition.
†††† Camera operates with sample temperature in the range of 4 – 50°C, and automatically powers off above 50°C.
Specifications subject to change without notice.