Analytical Chemist

About ScionxBio

ScionxBio is engineering the next generation of RNA medicines, combining synthetic chemistry and artificial intelligence to create xRNA - a platform for long-acting therapeutics. By expanding RNA beyond nature's four-letter alphabet, we engineer molecules that sustain protein expression for weeks to months rather than days, with the durability that chronic disease demands. With an initial focus on cardiometabolic disease, we are working to turn transient treatments into durable therapies. A spinout from Eleven Therapeutics, we are an international team operating across Cambridge (UK), Tel Aviv, and Cambridge (MA), with our Cambridge (UK) site serving as our largest research and development hub, and we are proud to foster a culture of collaboration, diversity, and scientific excellence. 

The Opportunity

We are looking for an ambitious, detail-oriented Analytical Chemist to join our fast-paced lab in Cambridge. In this role, you won't just run samples; you will directly power our pipeline by purifying and characterising novel mRNA constructs and chemically modified oligonucleotides. Working in a collaborative, interdisciplinary environment, you will support synthetic chemists, molecular biologists, and formulation scientists by delivering high-quality analytical data and executing routine downstream purification workflows. The ideal candidate is an adaptable scientist with a Master’s degree, practical experience with HPLC and LC-MS instruments, and a strong desire to build a career in RNA therapeutics. If you are eager to apply your separation chemistry skills to cutting-edge RNA medicines, we invite you to join our team.

Key Responsibilities

• Routine HPLC Purification: Execute semi-preparative and preparative HPLC methods to purify synthetic oligonucleotides, modified xRNA constructs, and mRNA samples to meet purity standards.


• Analytical Testing & Sample Analysis: Operate and maintain analytical instrumentation (HPLC, LC-MS) to assess the purity, concentration, and structural integrity of various RNA constructs.


• Chemical Characterisation: Prepare samples and perform routine LC-MS analysis to confirm chemical modifications and sequence identity.


• Downstream Processing: Conduct post-synthesis and post-purification handling, including desalting, lyophilization, gel analysis, concentration determination and aliquot preparation.


• Equipment Maintenance & Troubleshooting: Perform routine instrument maintenance, system suitability checks, and basic troubleshooting for HPLC and LC-MS systems to minimise downtime.


• Cross-Functional Support & Documentation: Maintain detailed laboratory notebooks, summarise analytical results clearly, and communicate data effectively to cross-functional teams in chemistry and biology.

Qualifications & Experience:

• Master’s degree (MSc or equivalent) in Analytical Chemistry, Biochemistry, Chemistry, or a closely related discipline.


• Direct hands-on industrial or internship experience operating HPLC systems and LC-MS instruments.


• Basic working knowledge of nucleic acid chemistry, synthetic oligonucleotides, or RNA concepts.


• Familiarity with common chromatographic techniques (e.g. Reversed-Phase, Ion-Pair RP, or Anion Exchange).


• Solid problem-solving skills with the ability to optimise oligonucleotide purification workflows.


• Attention to detail/strong documentation/willingness to learn in a fast paced interdisciplinary research environment.


• Strong communication and collaborative skills, dynamic and ability to thrive as part of a team.

ScionxBio is an equal opportunities employer. We celebrate diversity and are committed to creating an inclusive environment for all employees. We particularly welcome applications from people who are underrepresented in the sciences.