Senior Scientist Mass Spectrometrist
- United States - Connecticut - Groton
Use Your Power for Purpose
At Pfizer, our purpose is to deliver breakthroughs that change patients' lives. Central to this mission is our Research and Development team, which strives to translate advanced science and innovative technologies into impactful therapies and vaccines. Whether you are involved in discovery sciences, ensuring drug safety and efficacy, or supporting clinical trials, your role is crucial. You will leverage cutting-edge design and process development capabilities to accelerate the delivery of best-in-class medicines to patients globally.
What You Will Achieve
An opening is available for a Mass Spectrometrist in the Structure Elucidation Group within Pfizer Worldwide Research and Development’s Pharmaceutical Sciences Synthetic Molecule Division in Groton, CT. The Structure Elucidation Group plays a critical role across the pharmaceutical development continuum, supporting programs from drug substance through drug product and beyond. The team is responsible for the characterization of drug candidates, degradation products, and impurities, while partners closely with technology and project teams throughout Pfizer. This role offers the opportunity to develop and have a meaningful impact by advancing the Pfizer’s portfolio..
It is your innovative scientific temperament that will help in making Pfizer ready to achieve new milestones and help patients across the globe.
How You Will Achieve It
Elucidate chemical structures and solve scientific questions for small molecules of pharmaceutical interest using high resolution mass spectrometry tools.
Work within a team of disparate scientific disciplines as a subject matter expert (e.g., working closely with mass spectrometrists, NMR spectroscopists, purification scientists, analytical and organic chemists, etc.).
The individual will be expected to provide strong technical and strategic input to ensure efficient and timely execution of deliverables.
Investigate innovative scientific approaches to all aspects of mass spectrometry support for pharmaceutical development.
Utilize digital tools to enhance workflows.
Write technical documents.
Publish and present externally.
Qualifications
Must-Have
B.S./M.S. in chemistry with 9 to 11 years of experience in mass spectrometry focused on structural elucidation, or MBA/MS with 7 to 8 years of experience OR a Ph.D. 0 to 3 years of experience. in chemistry or equivalent with a focus on mass spectrometry applications (experience with peptide/proteomics preferred).
Strong understanding of mass spectrometry theory and applications.
Experience with the structure elucidation of small molecules and/or peptides.
Fundamental understanding of organic chemistry.
Familiarity with MS data analysis software for small molecules and peptides, such as Thermo Freestyle, ACD/Labs, BioPharma Finder, and Protein Metrics.
Ability to work independently in problem-solving and research.
Experience using HRMS systems, particularly Thermo Orbitrap instruments.
Strong communication skills.
Nice-to-Have
Experience in structural elucidation of small molecules using mass spectrometry. Knowledge of various ionization sources, mass analyzers and detectors required for structure elucidation of both API and complex drug product formulations.
Working knowledge of ionization induced fragmentation mechanisms and ability toutilize MS tools to propose solutions to a variety of structure/degradation questions. Fundamental understanding of organic chemistry.
A strong understanding of the theory and application of mass spectrometry. Experience with Thermo and Bruker systems.
Strong communication skills and a demonstrated ability to carry out independent research are required.
Strong interest and motivation to learn new technologies and concepts is expected.
Experience with MS processing software (Xcalibur, DataAnalysis, Masslynx, ACD etc.).
PHYSICAL/MENTAL REQUIREMENTS
This role requires the use of laboratory equipmentand working in laboratories.
Applicant must be able to adhere to safe laboratory practices. Some lifting may be required.
NON-STANDARD WORK SCHEDULE, TRAVEL OR ENVIRONMENT REQUIREMENTS
Relocation support available
Work Location Assignment: On Premise
Relocation assistance may be available based on business needs and/or eligibility.

Candidates must be authorized to be employed in the U.S. by any employer.
U.S. work visa sponsorship (such as TN, O-1, H-1B, etc.) is not available for this role now or in the future.

Sunshine Act
Pfizer reports payments and other transfers of value to health care providers as required by federal and state transparency laws and implementing regulations. These laws and regulations require Pfizer to provide government agencies with information such as a health care provider’s name, address and the type of payments or other value received, generally for public disclosure. Subject to further legal review and statutory or regulatory clarification, which Pfizer intends to pursue, reimbursement of recruiting expenses for licensed physicians may constitute a reportable transfer of value under the federal transparency law commonly known as the Sunshine Act. Therefore, if you are a licensed physician who incurs recruiting expenses as a result of interviewing with Pfizer that we pay or reimburse, your name, address and the amount of payments made currently will be reported to the government. If you have questions regarding this matter, please do not hesitate to contact your Talent Acquisition representative.
EEO & Employment Eligibility
Pfizer is committed to equal opportunity in the terms and conditions of employment for all employees and job applicants without regard to race, color, religion, sex, sexual orientation, age, gender identity or gender expression, national origin, disability or veteran status. Pfizer also complies with all applicable national, state and local laws governing nondiscrimination in employment as well as work authorization and employment eligibility verification requirements of the Immigration and Nationality Act and IRCA. Pfizer is an E-Verify employer. This position requires permanent work authorization in the United States.
Pfizer endeavors to make www.pfizer.com/careers accessible to all users. If you would like to contact us regarding the accessibility of our website or need assistance completing the application process and/or interviewing, please email disabilityrecruitment@pfizer.com. This is to be used solely for accommodation requests with respect to the accessibility of our website, online application process and/or interviewing. Requests for any other reason will not be returned.
To learn more about acceptable and prohibited uses of AI during the recruitment process, please review our candidate AI-use guidelines available on Pfizer Careers.

Research and Development
Breakthroughs that change patients’ lives
Research confirms what intuition tells us: that purpose-driven companies perform better, are more innovative, attract and retain the best people, and know how to unleash the power of those people. Pfizer’s purpose—Breakthroughs that change patients' lives—fuels everything we do and reflects our passion for building on our legacy as one of the greatest contributors of good to the world.
Each word in our purpose has meaning and reflects the value we strive to bring to patients and society:
“Breakthroughs” - These are the innovations, scientific and commercial, that we seek to deliver every day. All colleagues, regardless of role, level or location, strive for breakthroughs every day.
“Change” - We want to do more than simply improve patients’ medical conditions; we want to dramatically change their lives for the better.
“Patients’ lives” - We consider not only patients, but everyone they touch—including their families, caregivers, and friends—and everything they love to do. It’s an intentionally holistic view.
Our purpose ensures that patients remain at the center of all we do. We live our purpose by sourcing the best science in the world; partnering with others in the healthcare system to improve access to our medicines; using digital technologies to enhance our drug discovery and development, as well as patient outcomes; and leading the conversation to advocate for pro-innovation/pro-patient policies.
Every decision we make and every action we take is done with the patient in mind—and to nurture an environment where breakthroughs can thrive.
Our Values
To fully realize Pfizer’s purpose, we have established a clear set of expectations regarding “what” we need to achieve for patients and “how” we will go about achieving those goals.
The “how” is represented by four simple, powerful values—courage, excellence, equity, and joy—that define our company and our culture.
Courage: Breakthroughs start by challenging convention, especially in the face of uncertainty or adversity. This happens when we think big, speak up, and are decisive.
Excellence: We can only change patients’ lives when we perform at our best together. This happens when we focus on what matters, agree who does what, and measure our outcomes.
Equity: We believe that every person deserves to be seen, heard, and cared for. This happens when we are inclusive, act with integrity, and reduce healthcare disparities.
Joy: We give ourselves to our work, but it also gives to us. We find joy when we take pride, recognize one another, and have fun.
Pfizer Research & Development
Pfizer Research & Development serves as the beating heart of Pfizer's trailblazing product pipeline, the essence of our mission to bring life-changing medicines to the world.
With an unwavering commitment to innovation, we use a multidisciplinary approach that blends scientific expertise, cutting-edge technologies, and strategic collaborations, igniting a powerful engine that propels groundbreaking discoveries into life-saving treatments for patients in need.
Through our relentless pursuit of progress, we envision a future where cutting-edge medicines pave the way to healthier, happier lives worldwide.
Benefits at Pfizer
Pfizer offers competitive compensation and benefits programs designed to meet the diverse needs of our colleagues. Our Pay for Performance Philosophy and Practices reward colleagues based on the contributions they make to our business.
Our Competitive Benefits Programs help our colleagues by:
- Promoting Health and Wellness to help colleagues maintain and improve their physical and mental wellbeing. Pfizer offerings include health and disability insurance, preventative health programs, medical screenings, free or reduced-cost vaccinations, discounts on Pfizer products, mental health support, nutrition and fitness counseling and more.
- Strengthening Colleagues’ Financial Security by providing company contributions to retirement plans, life insurance and financial planning education to help colleagues achieve their financial goals.
- Providing Benefits and Time off for the Moments that Matter to ensure Pfizer colleagues have the time away from the office to recharge, recover and return to work as the best version of themselves. Vacation, Holiday time and Sick time are just the beginning, with a 12 week parental leave policy for both parents of a new born, 10 day of caregiver leave for those times when your family needs you whether it’s a child, spouse or parent, bereavement leave, and additional country-specific programs.
- And so much more, depending on your country and site, Pfizer offers childcare facilities or discount programs, on-site health and/or fitness centers, movement and mindfulness solutions, “Log in for your Day” work flexibility and so much more.
For U.S. based jobs, view an overview of Pfizer’s U.S. benefits program (opens in a new window)