Sr. Associate Scientist I - Microbiologist

At RayzeBio, every day is an opportunity to ignite meaningful change. As a wholly-owned subsidiary of Bristol Myers Squibb, RayzeBio blends the nimble, pioneering spirit of an emergent biotech with the global expertise and resources of a leading innovator in oncology. Our mission is to develop transformative radiopharmaceutical therapies that offer new hope for patients living with cancer. Here, you’ll join a multidisciplinary team where your ideas are valued, your expertise is amplified, and collaboration is at the heart of everything we do. From day one, expect to make an immediate impact—on our science, on our teams, and most importantly, on patients. Learn more about RayzeBio: https://careers.bms.com/rayzebio/

Job Description: Reporting to the Director of Microbiology, the Senior Associate Scientist I supports the routine operation of a Quality Control Microbiology laboratory supporting radiopharmaceutical manufacturing. This role performs routine microbiological release testing, including sterility, bacterial endotoxin, bioburden, and media qualification, in accordance with approved methods, SOPs, and cGMP requirements. The position also leads or supports method qualification/verification/validation, troubleshooting, investigations, and continuous improvement activities.

Key Responsibilities

• Perform routine sterility testing using approved methods and isolator or cleanroom systems in accordance with current SOPs and compendial requirements

• Execute bacterial endotoxin testing (BET) using approved methodologies and ensure accurate calculation, documentation, and review of results

• Conduct bioburden testing of raw materials, in‑process samples, and drug products using membrane filtration or plate count methods as defined in approved procedures

• Perform media qualification activities, including growth promotion testing, sterility checks, and physical inspection of media lots prior to use

• Execute method qualification, verification, and validation activities with minimal supervision.

• Troubleshoot assay issues and support out‑of‑trend (OOT) evaluations to drive timely resolution.

• Support continuous improvement initiatives, including adoption of new technologies and efforts that improve data visibility.

• Flexibility to support business needs (e.g., weekend work, early starts, or late end times) may be required

• Accurately document all testing activities in laboratory worksheets, logbooks, and electronic systems in a right‑first‑time manner

• Review data for completeness, accuracy, and compliance with SOPs and data integrity expectations

• Flexibility to support business needs (e.g., weekend work, early starts, or late end times) may be required

• Maintain inspection‑ready documentation and support internal audits and regulatory inspections as needed

• Maintain aseptic technique and proper gowning practices during all laboratory and cleanroom activities

• Ensure laboratory equipment, materials, and reagents are within calibration, qualification, and expiry prior to use

• Follow Environmental Health & Safety (EHS) policies and proper waste handling procedures

• Participate in routine laboratory maintenance, cleaning, and inventory activities

• Complete required GMP, safety, and method‑specific training prior to independent testing

• Collaborate effectively with peers, supervisors, QA, and cross‑functional partners

EDUCATION/EXPERIENCE/SKILLS

Education and Experience:

• BS/MS in Biology, Microbiology, or other Life Science related field with up to 3-5 years of relevant experience in production or quality control in a cGMP/FDA regulated facility.

• Experience with sterile manufacturing and/or radiopharmaceuticals strongly preferred.

Skills:

• Highly motivated and organized professional with the ability to work independently or in a team environment.

• Strong written and verbal communication skills required.

• Excellent professional ethics, integrity, and ability to maintain confidential information.

• Must be comfortable gowning in PPE to work in a cleanroom environment, working with ionizing radiation, and able to lift 40 lbs.

• Uses AI tools to enhance individual productivity and quality of work

#LI-Onsite

If you come across a role that intrigues you but doesn’t perfectly line up with your resume, we encourage you to apply anyway. You could be one step away from work that will transform your life and career.

The starting compensation range(s) for this role are listed above for a full-time employee (FTE) basis. Additional incentive cash and stock opportunities (based on eligibility) may be available. The starting pay rate takes into account characteristics of the job, such as required skills, where the job is performed, the employee’s work schedule, job-related knowledge, and experience. Final, individual compensation will be decided based on demonstrated experience. 
Eligibility for specific benefits listed on our careers site may vary based on the job and location. For more on benefits, please visit https://careers.bms.com/life-at-bms/.
 

Benefit offerings are subject to the terms and conditions of the applicable plans in effect at the time and may require enrollment. Our benefits include:

• Health Coverage: Medical, pharmacy, dental, and vision care.

• Wellbeing Support: Programs such as BMS Well-Being Account, BMS Living Life Better, and Employee Assistance Programs (EAP).

• Financial Well-being and Protection: 401(k) plan, short- and long-term disability, life insurance, accident insurance, supplemental health insurance, business travel protection, personal liability protection, identity theft benefit, legal support, and survivor support.

​Work-life benefits include:

Paid Time Off

• US Exempt Employees: flexible time off (unlimited, with manager approval, 11 paid national holidays (not applicable to employees in Phoenix, AZ, Puerto Rico or Rayzebio employees)

• Phoenix, AZ, Puerto Rico and Rayzebio Exempt, Non-Exempt, Hourly Employees: 160 hours annual paid vacation for new hires with manager approval, 11 national holidays, and 3 optional holidays

Based on eligibility*, additional time off for employees may include unlimited paid sick time, up to 2 paid volunteer days per year, summer hours flexibility, leaves of absence for medical, personal, parental, caregiver, bereavement, and military needs and an annual Global Shutdown between Christmas and New Years Day.

All global employees full and part-time who are actively employed at and paid directly by BMS at the end of the calendar year are eligible to take advantage of the Global Shutdown.

*Eligibility Disclosure: The summer hours program is for United States (U.S.) office-based employees due to the unique nature of their work. Summer hours are generally not available for field sales and manufacturing operations and may also be limited for the capability centers. Employees in remote-by-design or lab-based roles may be eligible for summer hours, depending on the nature of their work, and should discuss eligibility with their manager. Employees covered under a collective bargaining agreement should consult that document to determine if they are eligible. Contractors, leased workers and other service providers are not eligible to participate in the program.

RayzeBio and Bristol Myers Squibb

RayzeBio was acquired by Bristol Myers Squibb (BMS) in 2024 and is a wholly-owned subsidiary of BMS; however, RayzeBio will continue to operate as a standalone organization.

Supporting People with Disabilities

BMS and RayzeBio are dedicated to ensuring that people with disabilities can excel through a transparent recruitment process, reasonable workplace accommodations/adjustments and ongoing support in their roles. Applicants can request a reasonable workplace accommodation/adjustment prior to accepting a job offer. If you require reasonable accommodations/adjustments in completing this application, or in any part of the recruitment process, direct your inquiries to [email protected]. Visit careers.bms.com/eeo-accessibility to access our complete Equal Employment Opportunity statement.

Candidate Rights

BMS and RayzeBio will consider for employment qualified applicants with arrest and conviction records, pursuant to applicable laws in your area.

If you live in or expect to work from Los Angeles County if hired for this position, please visit this page for important additional information: https://careers.bms.com/california-residents/

Data Protection

We will never request payments, financial information, or social security numbers during our application or recruitment process. Learn more about protecting yourself at https://careers.bms.com/fraud-protection/

Any data processed in connection with role applications will be treated in accordance with applicable data privacy policies and regulations.

If you believe that the job posting is missing information required by local law or incorrect in any way, please contact BMS at [email protected]. Please provide the Job Title and Requisition number so we can review. Communications related to your application should not be sent to this email and you will not receive a response.