Microfluidic Modulation Spectroscopy (MMS): A Novel IR-Based Technique Providing Automated, Highly-Sensitive Protein Secondary Structure Characterisation in in situ Conditions

Patrick King

RedShiftBio Inc.


Infra-Red (IR) analysis has been long accepted as a powerful tool in protein characterization, particularly in the Amide I band (~1600 1700 cm-1), which gives detailed secondary-structural information that can be critical in determining protein structure-activity relationships, stability, batch-to-batch comparisons and in formulation studies as a few examples. Technologies traditionally used for secondary structure analysis, such as benchtop Fourier Transform IR (FTIR) or Circular Dichroism (CD), suffer from a number of issues that have prevented their routine use in this area, preventing this application from reaching its full potential. These include concentration and buffer restrictions, incompatibility with a range of excipients, a lack of automation, low spectral reproducibility and for FTIR, water subtraction problems.

Microfluidic Modulation Spectroscopy (MMS) is a new key technology that was brought to market in 2019 by RedShift Bioanalytics. It focuses on the IR Amide I region to produce exceptionally high data quality and reproducibility that aim to solve the aforementioned issues encountered with traditional technologies. It is fully automated, running samples from 24- and 96-well plates, compatible with a very broad concentration range (0.1 to >200 mg/ml), and is also compatible with a wide range of complex buffer systems and excipients, including those that absorb in the amide I region, surfactants and organic solvents. The platform includes a powerful software package that facilitates data analysis, and can be included in the automation procedure. This presentation highlights the technical benefits of MMS and its application in the protein structural workflow, giving relevant application examples.