Bioconjugation Scientist

Discover International; Philadelphia (Philadelphia County); On-site; USD 90,000 - 130,000; Full time

Job summary

Discover International is seeking a temporary, lab-based Bioconjugation Scientist for its Protein Sciences team in Philadelphia. The 6-month contract role involves bench work on protein purification, bioconjugation chemistry, and analytical characterization to support protein-toxin and siRNA-conjugate programs.

The ideal candidate will reliably execute experiments, document results in ELN, and collaborate with cross-functional teams in a fast-paced research environment.

Qualifications

• B.S./M.S. in Biochemistry, Chemistry, Chemical Engineering, Molecular Biology or related field.
• 5–8 years of hands-on industry lab experience in biotech/pharma/CDMO settings.
• Hands-on protein purification and chromatography experience (FPLC/AKTA, affinity, IEX, SEC).
• Direct bioconjugation experience; protein-toxin conjugates preferred.
• Experience with siRNA or oligonucleotide conjugation is desirable.
• Solid knowledge of analytical methods (SEC-HPLC, RP-HPLC, LC-MS, SDS-PAGE, UV-Vis).

Responsibilities

• Perform protein purification of recombinant proteins and bioconjugates using chromatography (FPLC/AKTA, affinity, IEX, SEC).
• Execute bioconjugation to generate protein-toxin conjugates and optimize reactions.
• Conjugate siRNA payloads to protein vehicles for various programs.
• Support analytical development and characterize proteins and conjugates (SDS-PAGE, HPLC, LC-MS).
• Maintain detailed ELN records and compliant lab documentation.
• Troubleshoot experiments, analyze data, and report results to the team.
• Collaborate with process development, analytical, and discovery biology teams.

Skills

Protein purification

Bioconjugation chemistry

Analytical techniques

Bench-based independence

ELN documentation

siRNA conjugation

Education

B.S./M.S. in Biochemistry, Chemistry, Chemical Engineering, Molecular Biology

Tools

FPLC/AKTA systems

Affinity chromatography

Ion-exchange chromatography

SEC/Size-exclusion

RP-HPLC

LC-MS

SDS-PAGE

Job description

Our client is seeking a temporary, lab-based Bioconjugation Scientist to join our Protein Sciences team for an initial 6-month contract, with the potential to extend based on program needs. This is a hands-on, bench-based role for an experienced scientist who is comfortable working independently at the lab bench on protein purification, bioconjugation chemistry, and analytical characterization in support of Client's protein-toxin conjugate and siRNA-conjugate programs. The ideal candidate is a self-starter who can step in quickly, execute experiments with minimal ramp-up, and contribute to a fast-paced, deadline-driven research environment.

Key Responsibilities

• Perform protein purification of recombinant proteins and bioconjugates using chromatography techniques such as affinity, ion-exchange, and size-exclusion chromatography (FPLC/AKTA systems).
• Execute bioconjugation reactions to generate protein-toxin conjugates, including conjugation chemistry optimization, reaction monitoring, and purification of conjugated species.
• Conjugate siRNA and other oligonucleotide payloads to protein targeting vehicles, supporting both proprietary and partnered programs.
• Support analytical development activities, including assay execution and characterization of proteins and conjugates (e.g., SDS-PAGE, SEC-HPLC, RP-HPLC, LC-MS, UV-Vis, and related techniques).
• Maintain detailed, accurate laboratory records and electronic lab notebooks (ELN) in compliance with good documentation practices.
• Troubleshoot experiments, analyze data, and communicate results clearly to project team members and stakeholders.
• Collaborate cross-functionally with process development, analytical, and discovery biology teams to advance conjugate candidates.
• Maintain lab equipment, reagent inventory, and adhere to all laboratory safety and quality standards.

Qualifications

• B.S. or M.S. in Biochemistry, Chemistry, Chemical Engineering, Molecular Biology, or a related life sciences discipline.
• 5-8 years of relevant, hands-on industry laboratory experience in a biotech, pharma, or CDMO/CRO setting.
• Demonstrated hands-on experience with protein purification and chromatography (FPLC/AKTA, affinity, IEX, SEC).
• Direct experience with bioconjugation chemistry; experience generating protein-toxin conjugates (e.g., ADC-like or similar payload conjugation) strongly preferred.
• Experience with siRNA or other oligonucleotide conjugation techniques is highly desirable.
• Working knowledge of analytical development and characterization techniques (SEC-HPLC, RP-HPLC, LC-MS, SDS-PAGE, UV-Vis, or similar).
• Comfortable working independently at the bench in a fast-paced, lab-based, full-time on-site role.
• Strong organizational skills, attention to detail, and clear written/verbal communication of experimental results.
• Prior experience in a small-biotech or start-up environment is a plus.