Lead Chemist (oil and surfactants) Rivercell
Data generation infrastructure for AI Virtual Cell models in drug discovery.
Permanent
Paris
No remote
Salary: Not specified
Skills we're looking for
Motivational skills
Windows
Primary
Assembly
Polymer
+3
You'll be part of
Artificial Intelligence / Machine Learning
Pharmaceutical / Biotech
Rivercell’s mission is to change how medicines are discovered by teaching AI to understand the human cell. Developing a single drug still takes years with an 90% failure rate in human. Predicting how cells respond to treatment before going to the lab would make it faster, and open up possibilities that are out of reach today.
That’s the promise of AI Virtual Cells: world models that learn the underlying rules of how cells respond to drugs and genetic changes, much as AlphaFold learned to predict protein structure. What holds them back is data. The vast, diverse, multimodal and time-resolved perturbational data they need doesn’t exist at scale, so we are building the infrastructure that generates it.
Our platform applies chemical and genetic perturbations to large cell populations and reads out their molecular and morphological responses at single-cell resolution, across millions of perturbation and context combinations. We then use that data to train our own world model of the cell.
Doing this takes a truly multidisciplinary team, where experts in thin films, microfluidics and instrumentation work side by side with experts in machine learning, computational biology and cell biology.
You'll be working on
We are looking for a hands-on Oil & Surfactant Lead Chemist to develop the fluidic operating system of Rivercell's platform and make it compatible with robust, high-throughput cell biology.
You will own the selection and optimization of carrier oils, surfactants, aqueous formulations, and operating protocols that enable reliable droplet manipulation while preserving cell viability and biological function. You will bridge microfluidics, interfacial physical chemistry, and cell biology.
You will work hand-in-hand with our device integration lead, surface engineering scientist, thin-film materials engineer, characterization engineer, assembly team, and cell biology team. You will also collaborate with an interdisciplinary group spanning genetic engineering, AI and software, bio-laboratory automation, optics, and electronics, and be an integral part of an ambitious startup project from its inception.
Select and optimize carrier oils based on viscosity, dielectric properties, conductivity, optical transparency, volatility, gas permeability, chemical stability, and biological compatibility
Select and optimize surfactants and interfacial additives to control droplet stability, coalescence, wetting, pinning, protein adsorption, and cell adhesion
Build formulation maps linking oil and surfactant composition, concentration, temperature, droplet size, waveform, frequency, and actuation performance
Evaluate formulations for cell viability, proliferation, morphology, membrane integrity, phenotype, and assay performance over relevant experimental durations
Adapt the fluidic system to complex media containing salts, serum, proteins, extracellular matrices, drugs, dyes, nucleic acids, and suspended cells
Characterize interfacial tension, viscosity, dynamic wetting, emulsion stability, evaporation, gas exchange, and the partitioning of water, proteins, and small molecules
Minimize cross-talk, reagent loss, fouling, osmotic drift, unwanted extraction, bubble formation, and contamination between droplets
Define chip priming, loading, filling, bubble-removal, sample-recovery, cleaning, storage, and preconditioning procedures
Design diagnostic experiments and translate results into formulation specifications, operating windows, quality controls, and standardized protocols
Opportunity to work on a cutting-edge project in the field of biotech
Opportunity to join an ambitious team and impactful startup among the first employees
Competitive salary and equity package
Exciting opportunities for personal and professional growth within the team
We're looking for
You have a PhD in microfluidics, chemical engineering, physical chemistry, soft matter, bioengineering, biophysics, or a related field.
You have 4+ years of hands-on experience developing microfluidic systems, multiphase formulations, emulsions, or droplet-based assays.
You have a strong understanding of wetting, capillarity, interfacial tension, surfactants, emulsions, mass transfer, and transport phenomena.
You can connect fluid properties and interfacial mechanisms to measurable device performance and biological outcomes.
You are comfortable exploring multidimensional formulation spaces and drawing practical conclusions from imperfect data.
You are autonomous, committed, enthusiastic, and comfortable working with a can-do, creative, and challenging mindset.
You are rigorous in experimental documentation, formulation traceability, data interpretation, and communication of uncertainty.
You have excellent communication skills and are fluent in English; professional proficiency in French is helpful but not required.
You have previous experience or knowledge in one or more of the following areas:
Droplet microfluidics, digital microfluidics, electrowetting, emulsions, or lab-on-a-chip systems
Fluorinated, silicone, or hydrocarbon oils; fluorosurfactants, non-ionic surfactants, block copolymers, or custom amphiphilic formulations
Cell culture, cell-based assays, organoids, primary cells, immune cells, or other sensitive biological samples
Tensiometry, contact-angle measurements, microscopy, particle tracking, or high-speed imaging
Design of experiments, formulation screening, statistical analysis, automated experimentation, or process development
Please let us know in your application if you specifically have experience with one or several of the following:
Optimizing oil and surfactant systems for mammalian cell culture or long-duration biological experiments
Quantifying partitioning, adsorption, reagent loss, cross-talk, or small-molecule transport in droplet systems
Working with fluorinated oils and biocompatible fluorosurfactants, including protein- or polymer-based surfactants
Electrowetting and the influence of conductivity, permittivity, viscosity, and waveform
Transferring fluid formulations and priming, filling, bubble-management, recovery, and cleaning protocols into repeatable operation
How we hire
Throughout the recruiting process, you will meet 4 to 6 team members of Rivercell.
Introductory call (up to 30mn, videocall)
Technical interview (up to 90mn)
Performance interview (up to 90mn, in person)
Culture interview (up to 60mn, in person)