Scientist / Senior Scientist

Yoh, A Day & Zimmermann Company; Sunnyvale (CA); On-site; USD 160,000 - 220,000; Full time

Benefits offered by this job

Medical benefits

HSA

401K Retirement Savings Plan

EAP

Certification and training

Job summary

Yoh, a Day & Zimmermann company, seeks a Senior Scientist to lead analytical validation for NGS-based molecular diagnostics in Sunnyvale. The role demands hands-on cfDNA workflow experience, robust NGS library prep knowledge, and expertise in regulated validation environments.

You will design studies, set acceptance criteria, and collaborate across assay development, bioinformatics, automation, quality, and regulatory teams to ensure assay performance and readiness for clinical milestones.

Qualifications

• Ph.D. required in a relevant scientific discipline.
• Hands-on experience with cell-free nucleic acid workflows or low-input molecular assays.
• Strong background in NGS library prep and sequencing workflows.
• Experience designing and executing analytical validation studies for molecular assays or NGS-based products.
• Knowledge of analytical sensitivity/specificity, LoB/LoD/LoQ, precision, and robustness testing.
• Ability to work independently in a multidisciplinary environment.

Responsibilities

• Design and execute analytical validation studies for molecular diagnostic assays and NGS-based testing platforms; develop study designs, acceptance criteria, sample size calculations, and statistical analysis plans.
• Lead validation studies covering LoB, LoD, LoQ, analytical sensitivity/specificity, repeatability, reproducibility, and variability assessments.
• Identify assay failure modes and implement corrective actions to improve performance.
• Perform and optimize workflows for plasma processing, cfDNA extraction, quantification, and quality assessment.
• Develop and qualify controls, reference materials, and test specimens for validation studies.
• Support characterization of low-abundance molecular signals and assay sensitivity limits.
• Operate and troubleshoot NGS instrumentation; analyze sequencing metrics and collaborate with bioinformatics teams.
• Generate technical summaries, validation reports, and performance assessments.
• Partner with automation engineers to transfer workflows to automated platforms; support workflow qualification and scale-up.
• Author validation protocols, reports, deviation investigations, and documentation in regulated environments.

Skills

Molecular biology

Analytical rigor

Statistical thinking

NGS workflows

Regulated assay development

Education

Ph.D. in Molecular Biology, Genetics, Genomics, Biochemistry, Bioengineering

Job description

Yoh is seeking a Senior Scientist, Analytical Validation – NGS & Molecular Diagnostics for an exciting opportunity with an innovative biotechnology client in the South Bay Area.

This role will be responsible for designing, executing, analyzing, and documenting analytical validation studies supporting advanced molecular diagnostic and next-generation sequencing (NGS) assays. The successful candidate will play a key role in establishing assay performance, reproducibility, robustness, and readiness for future clinical and regulatory milestones.

We are looking for a scientist who combines strong molecular biology expertise with analytical rigor, statistical thinking, and hands‑on experience in cell‑free nucleic acid workflows, NGS technologies, and regulated assay development environments.

Department

Assay Development / Research & Development

Location

Sunnyvale, CA

Employment Type

Full-time

Salary

$160,000 - $220,000 (DOE)

Analytical Validation Strategy & Execution

• Design and execute analytical validation studies for molecular diagnostic assays and NGS-based testing platforms.
• Develop scientifically sound study designs, acceptance criteria, sample size calculations, and statistical analysis plans.
• Lead studies evaluating:
  • Limit of Blank (LoB), Limit of Detection (LoD), and Limit of Quantitation (LoQ), as applicable
  • Analytical sensitivity and specificity
  • Repeatability and reproducibility
  • Operator, instrument, reagent lot, and workflow variability
  • Method comparison and analytical agreement
  • Interference, contamination, carryover, and assay robustness
  • Specimen and reagent stability
• Identify assay failure modes and implement corrective actions to improve performance and reliability.

Molecular Biology & NGS Assay Development

• Perform and optimize workflows involving plasma processing, cell‑free nucleic acid extraction, quantification, and quality assessment.
• Execute NGS library preparation workflows including:
  • End repair
  • Adapter ligation
  • Indexing
  • Amplification
  • Target enrichment
  • Library quality control
• Evaluate the impact of DNA input quantity, library efficiency, sequencing depth, and molecular background noise on assay performance.
• Develop and qualify controls, reference materials, and test specimens for validation studies.
• Support characterization of low‑abundance molecular signals and assay sensitivity limits.

NGS Data Analysis & Performance Assessment

• Operate and troubleshoot NGS instrumentation and associated workflows.
• Analyze sequencing and library quality metrics, including:
  • Read depth
  • Coverage uniformity
  • Mapping performance
  • Library complexity
  • Duplication rates
  • On‑target performance
• Collaborate with bioinformatics teams to evaluate analytical pipeline performance and quality‑control thresholds.
• Perform statistical analyses using tools such as R, Python, JMP, SAS, or equivalent platforms.
• Generate technical summaries, validation reports, and performance assessments.

Automation & Workflow Optimization

• Partner with automation engineers to transfer molecular workflows onto automated liquid‑handling platforms.
• Evaluate variability introduced by automation and support workflow qualification activities.
• Assess contamination control strategies, sample tracking systems, and recovery procedures.
• Support high‑throughput laboratory process development and operational scale‑up.
• Contribute to SOP development, troubleshooting guides, and workflow documentation.

Quality & Regulatory Support

• Author validation protocols, reports, deviation investigations, and technical documentation.
• Maintain traceable documentation for samples, instrumentation, reagents, software, and analytical methods.
• Support quality‑system initiatives and documentation practices consistent with regulated laboratory environments.
• Collaborate with Quality and Regulatory teams on validation strategies, verification activities, design controls, and submission‑support documentation.

Cross‑Functional Leadership

• Work closely with assay development, bioinformatics, automation, clinical, quality, and regulatory teams.
• Present study results, technical findings, and recommendations to project stakeholders.
• Lead technical investigations and support risk mitigation activities.
• Contribute to assay development strategy, validation planning, and project execution.

Required Qualifications

• Ph.D. in Molecular Biology, Genetics, Genomics, Biochemistry, Bioengineering, or a related scientific discipline.
• Hands‑on experience with cell‑free nucleic acid workflows, liquid biopsy technologies, or low‑input molecular assays.
• Strong background in NGS library preparation, sequencing workflows, and molecular assay development.
• Experience designing and executing analytical validation studies for molecular assays or NGS‑based products.
• Working knowledge of:
  • Analytical sensitivity and specificity
  • LoB, LoD, and LoQ studies
  • Precision and reproducibility assessments
  • Interference and robustness testing
  • Statistical study design and analysis
• Experience analyzing complex experimental data and applying appropriate statistical methodologies.
• Strong troubleshooting, documentation, experimental design, and scientific communication skills.
• Ability to work independently and effectively in a multidisciplinary environment.

Preferred Qualifications

• Experience supporting development or validation of liquid biopsy, cell‑free DNA (cfDNA), or other advanced molecular diagnostic assays.
• Experience with targeted sequencing, low‑frequency variant detection, DNA methylation analysis, or related technologies.
• Familiarity with FDA‑regulated diagnostic development programs and analytical validation frameworks.
• Knowledge of CLSI guidance and quality‑system requirements applicable to molecular diagnostics.
• Experience with laboratory automation and liquid‑handling systems.
• Proficiency in R, Python, JMP, SAS, or similar analytical tools.
• Experience with design controls, risk management, CAPA, method transfer, and assay lifecycle management.
• Experience supporting medium‑to‑high‑throughput laboratory operations.

Estimated Min Rate: $160000.00

Estimated Max Rate: $220000.00

What’s In It for You?

We welcome you to be a part of the largest and legendary global staffing companies to meet your career aspirations. Yoh’s network of client companies has been employing professionals like you for over 65 years in the U.S., UK and Canada. Join Yoh’s extensive talent community that will provide you with access to Yoh’s vast network of opportunities and gain access to this exclusive opportunity available to you. Benefit eligibility is in accordance with applicable laws and client requirements. Benefits include:

• Medical, Prescription, Dental & Vision Benefits (for employees working 20+ hours per week)
• Health Savings Account (HSA) (for employees working 20+ hours per week)
• Life & Disability Insurance (for employees working 20+ hours per week)
• MetLife Voluntary Benefits
• Employee Assistance Program (EAP)
• 401K Retirement Savings Plan
• Direct Deposit & weekly epayroll
• Referral Bonus Programs
• Certification and training opportunities

Note: Any pay ranges displayed are estimations. Actual pay is determined by an applicant's experience, technical expertise, and other qualifications as listed in the job description. All qualified applicants are welcome to apply.

Yoh, a Day & Zimmermann company, is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability, or status as a protected veteran.

Visit https://www.yoh.com/applicants-with-disabilities to contact us if you are an individual with a disability and require accommodation in the application process.

For California applicants, qualified applicants with arrest or conviction records will be considered for employment in accordance with the Los Angeles County Fair Chance Ordinance for Employers and the California Fair Chance Act. All of the material job duties described in this posting are job duties for which a criminal history may have a direct, adverse, and negative relationship potentially resulting in the withdrawal of a conditional offer of employment.

It is unlawful in Massachusetts to require or administer a lie detector test as a condition of employment or continued employment. An employer who violates this law shall be subject to criminal penalties and civil liability.