Kinetic Capillary Electrophoresis with Mass-Spectrometry Detection (KCE-MS) Facilitates Label-Free Solution-Based Kinetic Analysis of Protein-Small Molecule Interactions

摘要

1. KCE-MS is introduced as a platform for the development of label-free solution-based methods for studying kinetics of protein-small molecule interactions. 2. The off-line coupling allowed us to integrate a simple desalting/buffer exchange procedure between KCE and MS. 3. Our proof of principle suggests that efforts toward on-line interfacing of KCE and MS are justified. 4. The range of k_(on), k_(off), and K_d that can be measured by KCE-MS will be dependent on the efficiency of protein and small-molecule separat ion in KCE and on the MS detection limit. 5. Instrumentation for KCE-MS used in this study can measure K_d values as low as approximately 30 nM (see calibration curves). 6. The ability of MS to rapidly scan through m/z can facilitate simultaneous analysis of one protein with several small molecules and multiple interacting pairs which potentially can be used for high throughput screening of panels of drug candidates.