Senior Biosensing Scientist (Surface Chemistry & Biomolecular Interfaces)

Location: London, UK (in-lab) Type: Full-time Level: Senior Scientist / Individual Contributor (with clear pathway to technical leadership) 
Compensation: Competitive salary + meaningful early-stage equity options 

We’re seeking a Senior Biosensing Scientist to join our founding R&D team. 

This role is responsible for building the biochemical layer of our platform: engineering the molecular interfaces that allow our novel photonic sensors to monitor biology in real-time. You will lead the design and validation of reversible biorecognition interfaces for continuous monitoring. About us (Stealth mode): We’re a stealth, venture-backed healthtech building a next-generation wearable molecular sensing platform, leveraging novel light-based sensing in a wearable form factor. Our mission is to turn the body’s molecular signals into a continuous source of truth - unlocking real-time biochemical clarity for areas like fertility, infl ammation, metabolic health, and recovery. Today’s wearables track proxies (heart rate, sleep, movement), but the biology that drives health still lives in episodic, invasive lab tests. We’re closing that gap. The role: We are seeking a Senior Biosensing Scientist to play a foundational role in designing and validating the biorecognition interfaces at the heart of our sensing platform. This role focuses on engineering aptamer-based, surface-functionalised molecular probes that can selectively capture target biomarkers and release them in a controlled, reversible manner - enabling uninterrupted long-term monitoring. Your work will directly determine sensor stability, specifi city, regeneration performance, and real-world usability.

 You’ll work at the intersection of surface chemistry, molecular biology, and biosensing, collaborating closely with our photonics, microfl uidics, and systems teams to translate molecular design into robust continuous sensing hardware. 

You will own: 
● Affinity Probe Engineering: Design and development of surface-immobilized molecular probes (specifi cally nucleic-acid based) and synthetic ligands. 
● Continuous Sensing Logic: Engineering reversible capture-release mechanisms to enable uninterrupted monitoring without signal degradation.
● Surface Architecture: Optimizing linker chemistry and immobilization techniques to ensure maximum signal transduction on proprietary optical surfaces. ● Dynamic Validation: Characterizing probe behavior and kinetics in complex biological media and simulated wear environments. 
● Experimental Leadership: Using advanced tools (e.g., QCM, optical readouts) to establish the performance limits of our biorecognition layer. 

You’ll collaborate closely with leaders across photonics, microfl uidics, clinical, and product and play a key role in bringing a genuinely cutting-edge wearable technology from first prototypes to pilot-ready systems. 

The person: Ideal requirements: 
● PhD (or MSc + 3+ years) in Chemistry, Biochemistry, or Bioengineering or related. 
● Proven, hands-on experience working with aptamers (or closely related nucleic-acid affi nity probes) in a biosensing / affi nity-capture context - including assay development and performance optimisation. 
● Strong background in surface chemistry and biomolecule/protein immobilisation. 
● Demonstrated experience designing controlled capture and release / regeneration strategies suitable for repeated or continuous sensing. 
● Experience with fl uorescence and/or absorbance-based characterisation techniques. 
● Profi ciency with PCR-based workfl ows where relevant to biomarker/assay validation Nice to have (strong signals, not required) 
● Development of custom aptamers or nucleic-acid–based probes (e.g., optimisation, truncations/modifi cations, or SELEX exposure). 
● Design of novel synthetic affi nity ligands. 
● Hands-on experience with QCM analysis (or related kinetics tools). 
● Familiarity with continuous or real-time biosensing platforms. 
● Experience working with microfl uidic, wearable, or lab-on-chip systems. 
● Experience validating biomarkers in interstitial fl uid (ISF). 
● Experience handling skin tissue samples. 

Why work for us? 
● Foundational ownership: You’ll be a core contributor to the chemistry and biorecognition layer of the platform, directly shaping sensor performance, biomarker selection, and long-term reliability. Your work will defi ne what we can measure and how well we can measure it. 
● Deep-tech, real-world impact: Work on genuinely novel continuous biosensing technology with the potential to transform how health is monitored - moving biochemical insight from occasional lab tests to continuous, real-time understanding. 
● Work with exceptional people: collaborate with top-tier talent from Cambridge and Imperial College and leaders across sensing, chemistry, and product in a highly ambitious environment.
● High-pace, high-support culture: a fl at structure, fast iteration, and genuine room to experiment - with regular check-ins and feedback to support your growth and development. 
● Competitive compensation & meaningful equity: we offer competitive salary and early-stage share options, so you’ll own a real stake in what you’re building