FDA Postdoctoral Fellowship - Metabolic Activation of Nitrosamine Impurities

Position: ORISE Research Fellowship

Food and Drug Administration (FDA) – National Center for Toxicological Research (NCTR), Jefferson, Arkansas.

FDA-NCTR-

12/1/2026 3:00 PM Eastern Time Zone

This fellowship focuses on investigating the metabolism of nitrosamine drug substance‑related impurities (NDSRIs) and their potential impact on mutagenicity and carcinogenicity. You will collaborate with an interdisciplinary team of scientists to elucidate metabolic activation pathways of structurally complex NDSRIs, with a particular emphasis on DNA adduct formation, using in vitro metabolic systems and mammalian cell models. The studies will provide mechanistic insights into the structure‑activity relationships underlying the mutagenic and carcinogenic potency of NDSRIs and support improvements in (Q)
SAR modeling.

Under the guidance of the mentor, you will receive hands‑on training in mechanistic study design, experimental execution, and systematic evaluation in drug metabolism and chemical carcinogenesis.

• In vitro metabolism studies using liver S9 fractions, microsomes, and mammalian cell culture systems.
• Characterization of metabolites using HPLC‑UV, LC‑MS/MS, and 1H‑NMR.
• Identification and quantification of DNA adducts formed by NDSRIs in S9/microsomal incubations with DNA and in cell culture systems using 1H‑NMR and LC‑MS/MS.
• Presentation of findings at scientific conferences and publication in peer‑reviewed journals.

Qiangen Wu (qiangen.wu.gov)

October/November 2026 (flexible depending on factors)

Initially one year, renewal possible upon FDA recommendation and fund availability.

Full‑time

Monthly stipend commensurate with educational level and experience.

Open to U.S. citizens, lawful permanent residents, and qualified foreign nationals. Non‑U.S. citizen applicants must meet immigration status guidelines as outlined by the program website.

Proof of health insurance required for participation. Participants are not FDA employees and do not receive employment benefits.

Successful background investigation by Office of Personnel Management required and limited to individuals who have resided in the U.S. for at least three of the past five years.

• Non‑employee nature of the ORISE appointment.
• Prohibition on performing inherently governmental functions.
• Obligation to convey rights to FDA regarding intellectual property conceived or first reduced to practice.
• Research materials and laboratory notebooks belong to FDA.
• Protection of non‑public information.

• Doctoral degree in Chemistry, Materials Sciences, or related disciplines (received within last five years or anticipated by 12/31/2026).
• Strong background in chemical analysis, toxicology, or drug metabolism.

• Doctoral degree received within last 60 months or anticipated by 12/31/2026.
• Disciplines:
  Chemistry (including subfields), Materials Sciences, Life Health and Medical Sciences, etc.
• U.S. citizenship or residency of 36 months in the past 60 months.
• Read and understand FDA Ethics Requirements.