A new Taylor Dispersion Analysis (TDA)-based system from Malvern Instruments offers researchers a novel orthogonal technique to develop biopharmaceutical drug candidates. The Viscosizer TD speeds up stability and formulation studies by offering unique solution-based molecular sizing capabilities, combined with relative viscosity measurement. Ultra-low sample volumes, fully automated measurement protocols and precise environmental control for sample storage and measurement further enhance the value of the new system for early development screening.
TDA is a microcapillary flow-based technique that enables the sizing of small molecules, peptides and proteins, and samples containing mixtures of these species. Measurements of hydrodynamic size in different solution conditions are a critical element of screening and formulation studies because they give insight into the conformational stability and self-association behaviour of a candidate drug.
However, such measurements can be challenging because of the limited availability of target proteins at the candidate validation stage. Into early stage formulation development, candidate molecules are further worked up into complex buffer and excipient backgrounds, and can be present at a concentration — either high or low — that complicates analysis.
The Viscosizer TD uses TDA with UV-absorbance detection to directly address these issues and deliver hydrodynamic sizing in the range 0.2–50nm (radius). Target molecule detection is selective on the basis of the UV wavelength used in the measurement. In addition, the ability to baseline the system against a matched sample buffer offers novel measurement capabilities for the label-free analysis of biomolecules in complex formulations.
TDA can be used to monitor the stability and self-association of target molecules in mixtures of excipients and surfactants, for example, without measurement interference. Furthermore, measurements are not adversely affected by the presence of low levels of aggregates, so samples can be run without dilution of filtration. The capability to work in biologically relevant solutions makes TDA highly complementary to established tools such as Dynamic Light Scattering (DLS) and Size Exclusion Chromatography (SEC).
