Scientist, Delivery Sciences Lipid Chemistry

NewLimit•South San Francisco, CA

5d•$130,000 - $171,000•Onsite

About The Position

NewLimit is seeking a Lipid Chemist to design, synthesize, and characterize ionizable lipids, PEG-lipid Conjugates, peptide and antibody conjugates to build our targeting LNP platform with a particular focus on getting nucleic acid payloads into target cells and tissues beyond the liver. This is a hands-on bench role with real lipid design ownership. You will work closely with the Delivery Sciences and biology teams to design and build relevant Ionizable and targeting lipids portfolio for New Limit’s pipeline programs.

Requirements

PhD in Chemistry, Pharmaceutical Chemistry, or a related discipline, plus 1–2 years of relevant work; or an MS with 5 years of focused lipid design experience for liposomal or lipid nanoparticle applications.
Strong skill set in the design and synthesis of new lipids or other delivery chemistries, performed personally rather than with a supervisor directing each step.
SAR-driven design, synthesis, purification, and characterization of ionizable lipids and PEG-lipid conjugates, using tools such as ChemDraw, Sci-Finder, Reaxsys, and AI-based SAR prediction tools for tLNP applications.
Working knowledge of conjugation chemistries for attaching targeting moieties such as peptides, antibodies, nanobodies, and small-molecule ligands, including linker design and the selection of suitable biorthogonal or site-specific handles.
Practical purification skills spanning normal- and reverse-phase chromatography and preparative HPLC.
Analytical characterization across LC-CAD, LC-UV, LC-MS/MS, and NMR (¹H, ¹³C, and ³¹P as needed), with the ability to deconvolute the data to produce well-characterized lipids.

Nice To Haves

Familiarity with lipid degradation pathways and impurity work such as N-oxides, hydrolysis products, and lipid–nucleic acid adducts, and how they affect potency and stability.
Solid-phase peptide synthesis, or antibody/nanobody modification experience.
Exposure to scale-up, CMC, or tech transfer to a CDMO.
Experience with data visualization and statistical analysis (R, Python, JMP)

Responsibilities

Design new ionizable lipids and lipid conjugates for antibodies, peptides, and other targeting moieties across multiple structural families, pushing the platform beyond current-generation materials.
Devise and execute practical synthetic routes to priority targets to support NewLimit’s pipeline needs for targeting lipids.
Plan synthesis and purification for these modalities with scale and final purity in mind from the outset, delivering against agreed project timelines.
Build ionizable and targeting lipids for the tLNP platform using an SAR-based approach to guide the next design cycle rather than simply cataloging results.
Develop conjugation chemistry that links peptides, antibodies, nanobodies, and small-molecule ligands to lipid anchors, generating building blocks for cell- and tissue-selective delivery to support tLNP research and pipeline targets.
Turn in vitro and in vivo data from discovery teams into concrete structural hypotheses and revised molecules.
Present synthetic strategy, experimental results, and SAR conclusions, authoring protocols and technical reports.