Sr Research Scientist – Protein Chemist

We are seeking a highly motivated and experienced Protein Chemist to join the Structural Biology and Protein Production team within the Protein Science & Technology Department. The successful candidate will play a critical role in accelerating gene-to-structure workflows and antibody discovery programs. This is a highly collaborative role supporting small-molecule and biologics drug discovery programs. The ideal candidate will bring strong hands-on expertise in protein expression, purification, antibody purification, analytical characterization, and protein quality assessment.

• Independently design and optimize recombinant protein constructs for expression and downstream applications.
• Perform transfection of plasmids into mammalian cells, maintain cell lines, generate baculovirus, and express proteins in insect (Sf9) and mammalian systems.
• Express recombinant proteins using bacterial expression systems and optimize conditions to maximize yield, solubility, and quality.
• Develop, optimize, and execute protein purification workflows using chromatography techniques including affinity, ion-exchange, hydrophobic interaction, and size-exclusion chromatography (SEC).
• Develop and execute purification strategies for antibodies, antibody fragments, and antibody-containing complexes.
• Perform antibody purification and quality control, assessing purity, aggregation, integrity, concentration, and overall sample quality using appropriate analytical methods.
• Characterize purified proteins and antibodies using a broad range of biochemical and biophysical techniques, including analytical SEC/HPLC, SDS-PAGE, intact-mass analysis, DSF/thermal shift assays, BLI, SPR, and other analytical assays.
• Establish and apply protein and antibody quality-control criteria to ensure samples are suitable for structural studies, binding assays, biochemical assays, immunization campaigns, and other applications.
• Evaluate protein and antibody stability, homogeneity, aggregation state, concentration, and batch-to-batch consistency; identify potential quality issues and implement corrective strategies.
• Troubleshoot recombinant protein and antibody expression, purification, and stability challenges to improve yield, purity, monodispersity, and functional quality.
• Generate high-quality protein samples and protein complexes for X-ray crystallography, cryo-EM, biophysical studies, biochemical assays, and other structural biology applications.
• Support antibody discovery programs by providing purified and well-characterized antibody molecules and complexes for downstream functional and structural characterization.
• Independently plan and execute small- and large-scale expression, purification, and characterization experiments while effectively managing multiple projects and priorities.
• Contribute to the daily operations of a highly productive protein production laboratory, including maintaining equipment, improving workflows, and supporting laboratory development and technology implementation.
• Analyze and interpret experimental data, communicate results clearly, and make data-driven recommendations that influence program strategy and decision-making.
• Collaborate effectively with protein engineers, structural biologists, assay scientists, computational scientists, and project teams in a matrixed environment.
• Contribute to the development and implementation of AI-enabled and technology-driven approaches to accelerate protein production, characterization, structural biology, and drug discovery workflows.
• Maintain accurate experimental records and communicate results through presentations, written reports, and cross-functional project meetings.
• Work effectively in a fast-paced, dynamic environment while maintaining high scientific and operational standards.

• PhD in Biochemistry, Biophysics, Protein Chemistry, Molecular Biology, Structural Biology, or a related field with at least 2 years of relevant experience, or a Master's degree with at least 5 years of relevant experience in drug discovery, biotechnology, pharmaceutical research, or an academic laboratory.
• Demonstrated hands-on expertise in protein chemistry, recombinant protein expression, purification, and biophysical characterization.
• Experience with purification and characterization of antibodies and/or antibody fragments, including development and optimization of purification workflows and analytical quality control.
• Demonstrated experience evaluating protein and antibody purity, homogeneity, aggregation, stability, integrity, and suitability for downstream applications.
• Proficiency with chromatography-based purification techniques, including affinity, ion exchange, and analytical techniques such as SEC-HPLC, DSF/thermal stability assays, BLI.
• Ability to troubleshoot challenging protein expression and purification problems and independently develop effective solutions.
• Proven experience supporting drug discovery programs through protein chemistry.
• Ability to independently manage multiple projects, prioritize competing demands, and deliver high-quality results on established timelines.
• Excellent communication, collaboration, and interpersonal skills.
• Demonstrated ability to work effectively in cross-functional and matrixed teams.
• Self-driven, creative, scientifically curious, and entrepreneurial, with the ability to thrive in a fast-paced and evolving research environment.

This position is onsite, involving collaboration with a dynamic and cross-functional team in a fast-paced environment. The role requires maintaining high scientific and operational standards while working with cutting-edge technologies and equipment.

This is a Contract position based out of Wilmington, DE.

The pay range for this position is $40.00 - $43.27/hr.

Individual compensation offered for this position within this range will depend on many factors, including qualifications, skills, relevant experience, job knowledge, geographic location, internal equity, and other pertinent job-related factors.

Eligibility requirements apply to some benefits and may depend on your job classification and length of employment. Benefits are subject to change and may be subject to specific elections, plan, or program terms. If eligible, the benefits available for this temporary role may include the following: • Medical, dental & vision • Critical Illness, Accident, and Hospital • 401(k) Retirement Plan – Pre-tax and Roth post-tax contributions available • Life Insurance (Voluntary Life & AD&D for the employee and dependents) • Short and long-term disability • Health Spending Account (HSA) • Transportation benefits • Employee Assistance Program • Time Off/Leave (PTO, Vacation or Sick Leave)

This is a fully onsite position in Wilmington,DE.

This position is anticipated to close on Sep 29, 2026.

About Actalent

Actalent is a global leader in engineering and sciences services and talent solutions. We help visionary companies advance their engineering and science initiatives through access to specialized experts who drive scale, innovation and speed to market. With a network of almost 20,000 consultants and 5,000 clients across the U.S., Canada, Asia and Europe, Actalent serves many of the Fortune 500. We are proud to be an Engineering News-Record (ENR) Top 500 Design Firm for our engineering design services and a ClearlyRated Best of Staffing® winner for both client and talent service.

The company is an equal opportunity employer and will consider all applications without regard to race, sex, age, color, religion, national origin, veteran status, disability, sexual orientation, gender identity, genetic information or any characteristic protected by law.

If you would like to request a reasonable accommodation, such as the modification or adjustment of the job application process or interviewing process due to a disability, please email actalentaccommodation@actalentservices.com for other accommodation options.

San Francisco Fair Chance Ordinance: Pursuant to the San Francisco Fair Chance Ordinance, for all positions located in the city and county of San Francisco, we will consider for employment qualified applicants with arrest and conviction records.

Massachusetts Lie Detector: It is unlawful in Massachusetts to require or administer a lie detector test as a condition of employment or continued employment. An employer who violates this law shall be subject to criminal penalties and civil liability.

Use of Artificial Intelligence (AI): We may use Artificial Intelligence (AI) to support parts of our hiring process, including sourcing, screening, and evaluating candidates. AI helps assess applications and qualifications, but final decisions are made by our hiring team. By applying, you acknowledge and agree that your application may be reviewed using AI tools.