Scientist II, Mass Spectrometrist

Molecular Assemblies is a San Diego-based company developing a revolutionary, enzymatic DNA synthesis technology capable of powering new products in industrial synthetic biology, personalized therapeutics, precision diagnostics, and eventually information storage, nanotechnology and more.

The R&D organization is seeking an experienced and highly motivated mass spectrometrist at the Scientist II level to characterize synthetic DNA, RNA, and small molecule reagents. The position will report to the Director of Reagent Development and work closely with the Chemistry and Biochemistry Development teams to advance Molecular Assemblies’ proprietary oligonucleotide synthesis technology.


  • Leads development of analytical methods for mass characterization of synthetic oligonucleotides and precursors, including identification of impurities.
  • Collaborates with Chemistry and Biochemistry teams to support the goals of the R&D organization; including providing timely sample analysis as needed.
  • Communicates findings through technical reports and oral presentations.
  • Authors formal analytical procedures for routine testing and potential QC implementation.
  • Serves as subject matter expert for all mass spectrometry needs.
  • Maintains laboratory notebook using good documentation practices.
  • Trains and mentors junior staff.


  • Five plus years of hands-on experience in mass spectrometry with a thorough technical understanding of state-of-the-art technologies is required.
  • Demonstrated success in mass characterization of oligonucleotides is preferable. Transferable experience with other biological macromolecules may be considered.
  • Experience in mass analysis of small molecules and impurities is a plus.
  • Successful development and optimization of analytical HPLC methods is required.
  • Experience managing the upkeep of LC-MS instrumentation and associated troubleshooting is highly desirable.
  • Experience with Thermo LC-MS systems and BioPharma Finder software is desirable.
  • Working knowledge of synthetic biology (gene synthesis/DNA assembly/sequence design) is a plus.
  • Resourceful team player and collaborator.
  • Strong work ethic with excellent organizational skills.
  • Strong written, oral, and presentation communication skills.


Ph.D. in Chemistry, Biochemistry, or Molecular Biology with 2- years post-graduate experience. Exceptional B.S. or M.S. candidates with 10+ years direct mass spectrometry experience may be considered.

Please direct inquiries to