Scientist/Senior Scientist, Assay Development - Neuroscience Biomarkers

Spear Bio, founded in 2021, is a well-funded and rapidly growing biotech start-up headquartered in Woburn, Massachusetts. Our proprietary technology, Successive Proximity Extension Amplification Reaction (SPEAR), is a novel wash-free immunoassay platform, offering unprecedented sensitivity. We are dedicated to revolutionizing early disease diagnosis and monitoring by providing scalable, ultrasensitive solutions that deliver unparalleled accuracy in measuring low-abundant biomarkers, enabling clinicians and researchers to improve patient outcomes and advance global health. Scientist/Senior Scientist, Assay Development - Neuroscience Biomarkers: Our Assay Development team translates emerging biomarker science into robust assays for research and future clinical applications. We are seeking a Scientist / Senior Scientist who is intellectually curious, hands-on, self-motivated, and comfortable solving difficult scientific problems to play a pivotal role in advancing initiatives for our new range of ultrasensitive immunoassays. The ideal candidate combines deep neurobiology knowledge with experimental rigor, practical troubleshooting skills, and a strong sense of accountability. The successful candidate will help optimize assay strategies, identify the most relevant molecular forms and epitopes, evaluate preanalytical variables and matrix effects, interpret clinical-sample data, and troubleshoot complex assay-development challenges. We welcome applications from exceptional recent Ph.D. graduates and postdoctoral fellows who have demonstrated strong scientific ownership, as well as industry scientists who have rapidly taken on increasing responsibility in biotechnology or diagnostics environments. **This role is based onsite in our lab in Woburn, MA 5 days/week. Responsibilities: Develop a portfolio of ultrasensitive immunoassays throughout the product lifecycle, from initial screening and optimization through feasibility, verification, and transfer. Plan, design, and execute hands-on assay-development studies, including antibody selection and pairing, reagent conjugation, buffer optimization, reference-material evaluation, matrix characterization, and analytical validation for research and future clinical applications. Provide scientific leadership and translate biomarker biology into assay-design strategies by optimizing for clinically relevant molecular forms, isoforms, post-translational modifications, cleavage fragments, aggregation states, epitopes, and sample types. Analyze data from clinical and preclinical samples and interpret findings in the context of disease biology, sample characteristics, and published literature. Collaborate closely with Platform, Product Development, Operations, and Business Development teams to transition assays from feasibility through verification and transfer. Prepare clear scientific presentations, technical reports, study summaries, abstracts, and publications. Contribute to a rigorous, accountable, and highly collaborative startup environment. Requirements: Ph.D. in Neuroscience, Neurobiology, Molecular Biology, Biochemistry, Biomedical Engineering, or a closely related field. Strong scientific expertise in fluid biomarkers and assay-development strategies for the diagnosis, stratification, or therapeutic monitoring of neurodegenerative diseases, such as Alzheimer’s disease, Parkinson’s disease, or related neurological disorders. Strong understanding of biomarker heterogeneity and the factors that influence measurement in human biofluids. Hands-on experience developing immunoassays or other quantitative protein-detection methods. Demonstrated ability to design experiments independently and troubleshoot technical challenges. Evidence of meaningful scientific contributions through peer-reviewed publications, patents, conference presentations, or translational research programs. Strong written and verbal communication skills. Experience working in a startup or fast-paced biotechnology environment. A record of rapidly increasing scientific ownership, leadership, or responsibility. Can work 5 days/week on site in Woburn, MA . We offer competitive compensation, meaningful stock ownership, comprehensive benefits, and a great work environment. This is an opportunity to enter an innovative, high-growth startup at an early stage and play an integral role in the company's growth and success. We are focused on identifying candidates who have demonstrated leadership and excellence throughout their careers and are excited by the prospect of building an industry-leading company. Spear Bio Inc. provides equal opportunity in employment to all persons. No person shall be denied equal access because of race, creed, color, religion, national origin, sex, sexual orientation, gender identity, age, or physical/mental disability. Spear Bio does not accept resume submissions from external recruiting agencies. Any unsolicited resumes or candidate information submitted without prior written agreement will be deemed the property of Spear Bio, and no placement fees will be paid.