High-throughput MALDI TOF mass spectrometry platform for 5α-reductase inhibitor screening

Overview

This offering extends a proven high-throughput matrix-assisted laser desorption/ionisation time-of-flight (MALDI TOF) mass spectrometry drug discovery platform to the screening of 5α-reductase (5α-R) inhibitors. The technology directly measures both substrate and product by mass, enabling label-free, enzyme-class-agnostic screening of inhibitors for 5α-R1 and 5α-R2, enzymes implicated in androgen-related disorders including benign prostatic hyperplasia, androgenetic alopecia, and certain hormone-sensitive conditions.

The underlying approach has been published across multiple target classes, including kinases, deubiquitylases, E3 ligases, and proteases, and was recognised with the Biochemical Society Industry and Academic Collaboration Award 2022. By applying this platform to 5α-R, partners gain access to a rapid, miniaturised screening workflow that supports both primary single-dose campaigns and dose-response characterisation.

Technical specifications

Assay design:

• In vitro biochemical assay measuring conversion of testosterone to dihydrotestosterone by 5α-R1 and 5α-R2
• Readout based on a 2 Da mass shift, well resolved within the relevant mass range
• Activity quantified as the ratio of product to substrate ion intensities, with inhibition detected by a reduction in this ratio

Platform capabilities:

• 1536-well plate format analysed in approximately 8 minutes
• Supports both single-dose compound screening and IC50 determination in dose-response experiments
• Label-free detection; compatible with any enzyme inducing a mass shift where substrates and products ionise under MALDI TOF conditions
• Performed on the rapifleX PharmaPulse MALDI TOF mass spectrometer

Workflow:

• In vitro reactions will be optimised to achieve 20–50% substrate turnover, providing a robust baseline for inhibitor detection
• Initial feasibility assessment can be completed rapidly to confirm ionisation and resolution of testosterone and dihydrotestosterone

Technology readiness level

The core MALDI TOF high-throughput screening technology is mature, validated across multiple published target classes, and in active use. Application to 5α-reductase is at an early validation stage: no preliminary data for this enzyme class currently exist, and the next step is a short feasibility experiment to confirm ionisation behaviour and assay performance. Once validated, the platform is positioned to support full single-dose screening campaigns and downstream dose-response studies.