High-throughput and sensitive Taylor dispersion analysis of proteins using sequential injections

The size characterization of nano-objects in the 0.1–300 nm range can be achieved by Taylor dispersion analysis (TDA), with typical analysis times of 10–20 min in capillaries with an internal diameter of 50 μm. In TDA, longer detection times lead to improved detection sensitivity. To increase throughput while preserving sensitivity, sequential TDA is investigated, in which successive injections are performed within a single experiment without waiting for complete elution of the previous sample. In this work, the feasibility of sequential TDA applied to different protein samples is evaluated, using thyroglobulin and γ-globulin as model compounds. This strategy provides significantly higher analytical throughput without compromising detection sensitivity or the accessible sizing range of TDA. Based on five to six successive injections performed in a single run, the total analysis time can be reduced by a factor of more than three. Sequential analysis is not restricted to Gaussian fitting and can be also analyzed using Constrained Regularized Linear Inversion (CRLI).