Nanodroplet Array Platform for Integrated Synthesis and Screening of MEK Inhibitors: a Miniaturized Approach to Early Drug Discovery

M Maximilian Seifermann (Institute of Biological and Chemical Systems‐Functional Molecular Systems (IBCS‐FMS), Karlsruhe Institute of Technology (KIT) Hermann‐von Helmholtz‐Platz 1 Eggenstein‐Leopoldshafen 76344 Germany) J Julius Höpfner (Institute of Biological and Chemical Systems‐Functional Molecular Systems (IBCS‐FMS), Karlsruhe Institute of Technology (KIT) Hermann‐von Helmholtz‐Platz 1 Eggenstein‐Leopoldshafen 76344 Germany) L Liana Bauer (Institute of Biological and Chemical Systems‐Functional Molecular Systems (IBCS‐FMS), Karlsruhe Institute of Technology (KIT) Hermann‐von Helmholtz‐Platz 1 Eggenstein‐Leopoldshafen 76344 Germany) D Divya Varadharajan (Scivalon, Bruckenäcker 9 Stuttgart 70565 Germany) S Stefan Schmidt B Björn Fröhlich (Center for Mass Spectrometry and Optical Spectroscopy (CeMOS) Technische Hochschule Mannheim Paul‐Wittsack‐Straße 10 Mannheim 68163 Germany) B Benjamin Wellenhofer (Institute of Biological and Chemical Systems‐Functional Molecular Systems (IBCS‐FMS), Karlsruhe Institute of Technology (KIT) Hermann‐von Helmholtz‐Platz 1 Eggenstein‐Leopoldshafen 76344 Germany) C Charlotte Luchena (Institute of Biological and Chemical Systems‐Functional Molecular Systems (IBCS‐FMS), Karlsruhe Institute of Technology (KIT) Hermann‐von Helmholtz‐Platz 1 Eggenstein‐Leopoldshafen 76344 Germany) C Carsten Hopf A Anna A. Popova (Institute of Biological and Chemical Systems‐Functional Molecular Systems (IBCS‐FMS), Karlsruhe Institute of Technology (KIT) Hermann‐von Helmholtz‐Platz 1 Eggenstein‐Leopoldshafen 76344 Germany) P Pavel A. Levkin (Institute of Biological and Chemical Systems‐Functional Molecular Systems (IBCS‐FMS), Karlsruhe Institute of Technology (KIT) Hermann‐von Helmholtz‐Platz 1 Eggenstein‐Leopoldshafen 76344 Germany)

Abstract

Abstract Early‐stage drug discovery relies on high‐throughput screenings, which are costly and time‐intensive, limiting access for academic laboratories and small companies. A key bottleneck is the lack of miniaturization and the separation of compound synthesis from screening. We present a nanoliter droplet array platform integrating synthesis, characterization, and cell‐based screening of 325 MEK (mitogen‐activated protein kinase kinase) inhibitors, targeting the MAPK/ERK (mitogen‐activated protein kinase/extracellular signal‐regulated kinase) pathway, implicated in colorectal and pancreatic cancer. The platform enables on‐chip synthesis, MALDI‐MSI (matrix‐assisted laser desorption/ionization‐mass spectrometry imaging) characterization, and cell‐based screening within 200 nL droplets containing 20 nmol starting material (∼4 ng final compound), and only 300 cells per droplet. Screening identified 46 compounds with higher cytotoxicity than mirdametinib, a clinically approved MEK inhibitor. Molecular docking revealed a shared allosteric binding mechanism, indicating non‐competitive ATP inhibition. Synthesis and screening of all 325 compounds were completed within 7 days, requiring <10 mg of reactants, <250 µL solvent, and ∼100 µL of cell suspension (∼100,000 cells in total). Our results demonstrate that integrating miniaturized combinatorial synthesis and biological screening in a single platform can accelerate early‐stage drug discovery while reducing cost and resource use.

Article Details

Volume / Issue Vol. 64, Issue 48
Published November 24, 2025
ISSN 1433-7851
Publisher Wiley

Journal Info

Angewandte Chemie International Edition

Wiley

ISSN: 1433-7851 Physical Sciences

Authors (11)

M

Maximilian Seifermann

Institute of Biological and Chemical Systems‐Functional Molecular Systems (IBCS‐FMS), Karlsruhe Institute of Technology (KIT) Hermann‐von Helmholtz‐Platz 1 Eggenstein‐Leopoldshafen 76344 Germany

J

Julius Höpfner

Institute of Biological and Chemical Systems‐Functional Molecular Systems (IBCS‐FMS), Karlsruhe Institute of Technology (KIT) Hermann‐von Helmholtz‐Platz 1 Eggenstein‐Leopoldshafen 76344 Germany

L

Liana Bauer

Institute of Biological and Chemical Systems‐Functional Molecular Systems (IBCS‐FMS), Karlsruhe Institute of Technology (KIT) Hermann‐von Helmholtz‐Platz 1 Eggenstein‐Leopoldshafen 76344 Germany

D

Divya Varadharajan

Scivalon, Bruckenäcker 9 Stuttgart 70565 Germany

S

Stefan Schmidt

B

Björn Fröhlich

Center for Mass Spectrometry and Optical Spectroscopy (CeMOS) Technische Hochschule Mannheim Paul‐Wittsack‐Straße 10 Mannheim 68163 Germany

B

Benjamin Wellenhofer

Institute of Biological and Chemical Systems‐Functional Molecular Systems (IBCS‐FMS), Karlsruhe Institute of Technology (KIT) Hermann‐von Helmholtz‐Platz 1 Eggenstein‐Leopoldshafen 76344 Germany

C

Charlotte Luchena

Institute of Biological and Chemical Systems‐Functional Molecular Systems (IBCS‐FMS), Karlsruhe Institute of Technology (KIT) Hermann‐von Helmholtz‐Platz 1 Eggenstein‐Leopoldshafen 76344 Germany

C

Carsten Hopf

A

Anna A. Popova

Institute of Biological and Chemical Systems‐Functional Molecular Systems (IBCS‐FMS), Karlsruhe Institute of Technology (KIT) Hermann‐von Helmholtz‐Platz 1 Eggenstein‐Leopoldshafen 76344 Germany

P

Pavel A. Levkin

Institute of Biological and Chemical Systems‐Functional Molecular Systems (IBCS‐FMS), Karlsruhe Institute of Technology (KIT) Hermann‐von Helmholtz‐Platz 1 Eggenstein‐Leopoldshafen 76344 Germany