Sr. Associate Scientist

Make a global impact—join Repligen.
We’re united by a mission to inspire advances in bioprocessing as a preferred partner in the production of biologic drugs that improve human health worldwide. No matter your role or background, at Repligen, you will play a key part in shaping some of the most innovative and life-changing therapies in the world. We foster a culture of purpose, collaboration, and shared success—where every voice matters and every contribution drives progress. Join us!
The Sr. Associate Scientist is a hands-on R&D role focused on the development and evaluation of membrane-based separation technologies for downstream bio-processing, with an emphasis on ultrafiltration and tangential flow filtration (TFF) applications. This position performs laboratory and pilot scale experiments with a high degree of independence, carrying out defined experimental plans to support product and process development including concentration, diafiltration, and purification of biologics, while troubleshooting issues and generating reliable, high-quality data. The role analyzes and interprets results, identifies performance trends, and communicates clear conclusions to support product design, scalability, and customer applications, including preparation of internal reports and supporting technical papers. Working closely with cross functional teams including R&D, Product Management, and Manufacturing, the Sr. Associate Scientist supports new product development, line extensions, and continuous improvement efforts within Repligen’s filtration portfolio. Ability to accomplish goals with limited supervision while collaborating with colleagues and providing technical guidance as needed.
This role is expected to model our Leadership Behaviors—Integrity & Compliance, Customer Focus, Collaboration, Courage, Team Empowerment, and Accountability & Results—in all aspects of work.

Responsibilities

• Execute laboratory and pilot-scale experiments to support development of membrane-based filtration products, with a focus on ultrafiltration and tangential flow filtration (TFF) applications for biologics processing
• Independently carry out experimental plans, including system setup, operation, and troubleshooting of filtration hardware, ensuring consistent and reliable data generation
• Generate, analyze, and interpret experimental data; identify trends, assess performance, and communicate clear, data-driven conclusions
• Support development of downstream bioprocessing applications including protein concentration, diafiltration, and purification across varying conditions and scales
• Troubleshoot membrane, device, and process performance issues and recommend practical, technically sound solutions
• Prepare internal technical reports, data summaries, and supporting white papers to document findings
• Collaborate with cross-functional teams to support product development, line extensions, and continuous improvement efforts
• Maintain laboratory equipment and ensure proper operation while adhering to safety practices
• Provide technical guidance and collaborate across the team

Required Qualifications

• Bachelor’s degree in chemical engineering, Chemistry, Biochemistry, or a related scientific or engineering discipline
• 3–5+ years of relevant industry experience in bioprocessing, filtration, or related environments
• Ability to execute experiments independently and manage multiple priorities with limited supervision
• Strong data analysis and problem-solving skills
• Ability to work effectively in cross-functional teams
• Strong written and verbal communication skills including technical report writing

Preferred Qualifications

• Hands-on experience with membranes, TFF cassettes (hollow fiber), ultrafiltration diafiltration, and/or tangential flow filtration (TFF) systems
• Experience operating, troubleshooting, and maintaining laboratory or pilot scale equipment
• Familiarity with downstream bioprocessing applications such as protein concentration, purification, or buffer exchange
• Experience with membrane manufacturing development, filtration device manufacturing development, filtration device failure analysis.
• Experience preparing technical reports and supporting white papers
• Experience using statistical or data analysis tools (e.g., JMP, Minitab, Excel, or similar) for data evaluation, visualization, and trend analysis
• Hands-on experience with analytical techniques such as UV/Vis, pH, conductivity, HPLC, FTIR, or similar methods for routine sample and process characterization

Physical / Laboratory Requirements

• Hands on laboratory role requiring operation of pumps, tubing systems, and filtration equipment
• Ability to lift up to 25–50 lbs. and work in a laboratory environment
• Must follow established safety procedures and handle chemicals appropriately

This role is not eligible for employment-based immigration sponsorship. Applicants must be legally authorized to work in the United States without employer sponsorship.

Our mission is to inspire advances in bioprocessing as a trusted partner in the production of biologic drugs that improve human health worldwide. Focused on cost and process efficiencies, we deliver innovative technologies and solutions that help set new standards in bioprocessing. The estimated salary range for this role, based in the United States of America is $85,000-121,900. Compensation decisions are dependent on several factors including, but not limited to an individual's qualifications, location, internal equity, and alignment with market data. Additionally, employees are eligible to participate in one of our variable cash programs (bonus or commission) and eligible roles may receive equity as part of the compensation package. We offer a wide range of benefits such as paid time off, health/dental/vision, retirement benefits and flexible spending accounts. All compensation and benefits information will be confirmed in writing at the time of offer.