Meet the Team

Raphael H. Valdivia, PhD
Co-Director

Dr. Valdivia is the Nanaline H. Duke Distinguished Professor of Molecular Genetics and Microbiology. He is the Chair of the Department of Immunology, and a member of the Duke Cancer Institute. As the Co-Director of the DCI Flow Core, Dr. Valdivia provides invaluable scientific and administrative oversight and ensures that the core continues to maintain and provide state-of-the-art technologies and outstanding services to the members of the DCI and other Duke investigators. Dr. Valdivia’s laboratory is one of the major users of the DCI Flow Core, and his laboratory is interested in how microbes influence human health, both in the context of host-pathogen and host-commensal interactions.

Contact Information:
4112 MSRB III Box 3580, 3 Genome Court, Durham, NC 27710
Email: raphael.valdivia@duke.edu
Phone: (919) 668-3831

More about Dr. Valdivia here
Learn more about Valdivia lab here


Javid P. Mohammed, M.Sc., M.S
Co-Director

Javid Mohammed oversees day-to-day operations of the DCI Flow Core, in addition to providing experimental consultation involving high-dimensional flow cytometry, cell sorting and various downstream applications. Under his leadership, the flow core continues to keep pace with the advances in current technologies and the team stays abreast of the flow cytometry methodologies. He also evaluates and implements new instrumentation and services, training programs (for both clients and staff), SOPs and best practices to be able to continue providing outstanding flow cytometry and cell sorting services. Javid collaborates with investigators to help them design and develop custom flow cytometry assays as well.

Contact Information:
207 Research Drive, Durham, NC 27710 (Office: Jones#306)
Email: javid.mohammed@duke.edu
Phone: (919) 613-7818

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Team Members

Lynn Martinek, Flow Cytometry Research Analyst

Lynn has been part of DCI Flow Core since 1996. She provides assisted cell sorting services on the MoFlo Astrios cell sorter and is the primary contact for DCI Flow Core Biosafety compliance. She provides hands-on training on FortessaX20 and assists clients with troubleshooting instrument issues on Fortessa, FACSCanto and Sony sorters. Lynn loves helping students on their way to earning a PhD, while supporting research here at Duke. When she is not sorting on the Astrios, you will usually find her enjoying a hike in the mountains.

Bin Li, PhD., Flow Cytometry Research Analyst

Bin joined DCI Flow Core in July 2011. Prior to that, he was a postdoc in the Department of Pediatrics at Duke and conducted research in transplantation Immunology. He holds a Ph.D. in Microbiology and Immunology from the National University of Singapore, where his graduate research focused on Graft Versus Host Disease (GVHD). Bin provides assisted cell sorting services and is the primary contact for BD Diva cell sorter. He provides hands-on training on FACSCanto, Fortessa, Aurora, and Sony sorters. Bin enjoys playing badminton and pickleball in his spare time.

Yingqiu (Ying) Guo, PhD., Flow Cytometry Research Analyst

Ying joined DCI Flow Core in July 2021. She has worked in several different labs and has extensive experience with biological research and clinical trials. She is the primary contact for hands-on training on SonySH800 and SonyMA900 cell sorters and provides assisted cell sorting services on the Sony MA900. Ying assists clients with troubleshooting instrument issues on Fortessa, FACSCanto, Aurora and Sony sorters and oversees instrument maintenance. In her spare time, she likes traveling and spending time with her family.

Scientific Advisor

Michael S. Krangel, PhD
Scientific Advisor, Former Director of the DCI Flow Core

Dr. Krangel is the George Barth Geller Distinguished Professor of Immunology and a member of the Duke Cancer Institute. He is the former Chair of the Department of Immunology and the former Director of the DCI Flow Cytometry Shared Resource between 2009 and 2022. Under his leadership, the DCI Flow Core evolved into a state-of-the-art facility to provide outstanding services to the members of the DCI. Dr. Krangel played a vital role in implementing the latest Flow Cytometry technologies and methodologies within the core, including the most recent spectral cytometry technology to support high-dimensional flow cytometry. The DCI Flow Core is grateful to have Dr. Krangel’s continued support, vision and scientific oversight that enables us to ensure the technologies and services provided by the core continue to meet the needs of the DCI investigators. More about Dr. Krangel here