Medium Throughput Screening
The throughput of native MS (non-covalent MS, non-denaturing, supermolecular MS) analysis has been substantially boosted by the introduction of an automated microfluidic chip-based nano-electrospray ionization interface. Coupling time-of-flight mass spectrometers to the Triversa Nanomate® has increased screening throughput to 96 – 384 samples a day. Such throughput is a useful secondary screening tool for hits selected from high throughput screens.
Native MS is certainly applicable to screening small sized libraries, up to several thousand of compounds. It is also practicable to screen libraries in the tens of thousands by using a multiplex approach (several compounds per sample). NovAliX software developments deliver rapid evaluation of the large amount of data generated. Native MS as a screening technique works particularly well for complexes with dissociation constants extending up to the low three-digit micromolar region.
Several valuable quantitative and qualitative parameters may be determined; namely binding stoichiometry, specificity and affinity range. Interesting hits may be characterized in greater depth in respect of the reversibility of binding, target site selectivity, binding affinity and gas phase stability.
The combination of speed, material efficiency and quality of data make native MS worthy of serious consideration either as a cost effective alternative to other screening technologies or an orthogonal methodology for the verification of hits from other platforms.