Senior Scientist, LNP Formulations

Serif Biomedicines•Cambridge, MA

18h•Onsite

About The Position

Serif Biomedicines is seeking a highly motivated Senior Scientist II with deep expertise in lipid chemistry to advance the design of novel ionizable lipids and next-generation lipid nanoparticle (LNP) formulations for nucleic acid delivery. The role focuses on rationally designing and synthesizing ionizable lipids, optimizing LNP molar compositions, and preparing formulations to screen and benchmark new lipids. It brings together medicinal and organic chemistry, formulation science, and delivery biology, with molecules moving rapidly from bench synthesis into functional LNPs. The successful candidate will work independently, influence cross-functional program direction, and identify innovative solutions to advance platform capabilities. The role also involves mentoring junior scientists, contributing to scientific strategy and the delivery platform’s intellectual property position, and engaging with the broader scientific community. The position is located in Cambridge, Massachusetts.

Requirements

PhD in Organic Chemistry, Medicinal Chemistry, Chemical Biology, Pharmaceutical Sciences, or a related field, with at least 5 years of relevant industry experience; or an M.S. with at least 8 years of experience.
Strong background in multi-step organic synthesis, purification, and structural characterization, ideally involving lipids, amphiphiles, or other delivery materials.
Hands-on experience with LNP formulation, such as microfluidic mixing or nanoprecipitation, and understanding of how lipid structure and molar composition affect potency, stability, and tolerability.
Experience designing and conducting formulation screens, including characterization by DLS, encapsulation assays, and pKa determination.
Demonstrated ability to design experiments, analyze data, and solve complex technical problems.
Strong communication and collaboration skills, and experience mentoring junior scientists.

Nice To Haves

Experience with nucleic acid delivery, including mRNA, DNA, or siRNA, is highly preferred.
Familiarity with lipid analytics such as NMR, LC-MS, and HPLC-CAD/ELSD.
Familiarity with computational or data-driven approaches to lipid design.
A record of innovation, such as publications or patents.

Responsibilities

Design and synthesize novel ionizable lipids, including head-group, linker, and tail variants, using structure-activity relationships and the pKa, biodegradability, and tolerability profiles of each series to guide design.
Lead the design of LNP molar compositions, optimizing ionizable lipid, helper lipid, cholesterol, and PEG-lipid ratios and exploring alternative or novel excipients for potency, stability, and tolerability.
Prepare small-scale LNP formulations using microfluidic or other mixing methods to support medium- to high-throughput screening of lipids and compositions.
Plan and conduct formulation screening studies, define critical formulation parameters, and build structure-property relationships across lipid libraries.
Characterize lipids and LNPs using appropriate analytical methods, including NMR, LC-MS, HPLC with CAD/ELSD, DLS, encapsulation assays, and apparent pKa assays; ensure lipid identity and purity.
Collaborate with biology, analytical, process development, and external partners to evaluate lead formulations in vitro and in vivo, and use results to guide subsequent design cycles.
Analyze and interpret experimental data, maintain detailed documentation, and communicate findings clearly to internal stakeholders.
Mentor junior scientists and contribute to scientific strategy and the delivery platform’s intellectual property position.
Stay current with advances in ionizable lipid chemistry, LNP technologies, and nucleic acid delivery.