Senior Scientist - Ionizable Lipids & LNP Formulations

Flagship Pioneering, Inc.; Cambridge (MA); On-site; USD 126,000 - 182,000; Full time

Benefits offered by this job

Frontier lipid science

Collaborative culture

Competitive package

Job summary

Serif Biomedicines in Cambridge, MA is seeking a Senior Scientist II with deep expertise in lipid chemistry to drive the design of ionizable lipids and next-generation LNP formulations for nucleic acid delivery. The role focuses on rational design, synthesis, and evaluation of new lipids and formulations.

As a senior contributor, you will mentor junior scientists, influence cross-functional program direction, and contribute to the broader scientific strategy and IP position of the delivery

Qualifications

• PhD in Organic Chemistry with 5+ years in industry or MS with 8+ years of experience.
• Strong background in multi-step organic synthesis, purification and structural characterization of lipids or related delivery materials.
• Hands-on LNP formulation experience (microfluidic mixing, nanoprecipitation) and understanding of lipid structure on potency and tolerability.
• Experience designing formulation screens and evaluating by DLS, encapsulation and pKa.
• Nucleic acid delivery experience (mRNA, DNA, siRNA) preferred.
• Familiarity with lipid analytics (NMR, LC-MS, HPLC-CAD/ELSD) and data-driven lipid design is a plus.
• Demonstrated ability to design experiments, analyze data, and mentor junior scientists.

Responsibilities

• Design and synthesize novel ionizable lipids and explore head group, linker and tail variants.
• Lead LNP molar composition design to optimize potency, stability, and tolerability.
• Prepare LNP formulations at small scale for medium- to high-throughput screening.
• Plan formulation screening studies and build structure–property relationships across lipid libraries.
• Characterize lipids and LNPs using NMR, LC-MS, HPLC-CAD/ELSD, DLS and pKa assays.
• Collaborate with biology, analytics, process development and external partners to evaluate lead formulations.
• Analyze data, document results, and communicate findings to stakeholders.
• Mentor junior scientists and contribute to scientific strategy and IP position.
• Stay current with advances in ionizable lipid chemistry and nucleic acid delivery.

Skills

Lipid chemistry

Organic synthesis

LNP formulation

DLS analysis

NMR / LC-MS

Mentoring

Education

PhD in Organic Chemistry

MS with 8+ years experience

Tools

LC-MS

NMR

HPLC-CAD/ELSD

DLS

Job description

Serif Biomedicines in Cambridge, MA is seeking a Senior Scientist II with deep expertise in lipid chemistry to drive the design of ionizable lipids and next-generation LNP formulations for nucleic acid delivery. The role focuses on rational design, synthesis, and evaluation of new lipids and formulations.

As a senior contributor, you will mentor junior scientists, influence cross-functional program direction, and contribute to the broader scientific strategy and IP position of the delivery