Honors & Awards

  • T32 Stanford Molecular Imaging Program, NIH (2023-2025)
  • Jack Krohmer Early-Career Investigator Award, AAPM Annual Meeting (2023)
  • Bio-X Travel Award, Stanford University (2023)
  • Expanding Horizons Travel Award, AAPM (2022)
  • Radiation Oncology Trainee Seed Grant, Stanford University School of Medicine (2022)
  • School of Medicine Dean's Postdoctoral Fellowship, Stanford University (2022)
  • Presidential Fellowship in Biomedical Engineering, The University of Texas at Austin (2020)
  • Professional Development Award, The University of Texas at Austin (2020)
  • Graduate Fellowship, The University of Texas at Austin (2019)
  • Singapore Government Scholarship, Singapore Ministry of Foreign Affairs (2007-2011)

Professional Education

  • Master of Science in Engr, University of Texas Austin (2019)
  • Doctor of Philosophy, University of Texas Austin (2020)
  • Ph.D., The University of Texas at Austin, Biomedical Engineering (2020)
  • M.S., The University of Texas at Austin, Biomedical Engineering (2019)
  • B.E., Nanyang Technological University, Singapore, Materials Science and Engineering (2011)

Stanford Advisors

All Publications

  • Efficient and multiplexed tracking of single cells using whole-body PET/CT. bioRxiv : the preprint server for biology Nguyen, H. T., Das, N., Wang, Y., Ruvalcaba, C., Mehadji, B., Roncali, E., Chan, C. K., Pratx, G. 2023


    In vivo molecular imaging tools are crucially important for elucidating how cells move through complex biological systems, however, achieving single-cell sensitivity over the entire body remains challenging. Here, we report a highly sensitive and multiplexed approach for tracking upwards of 20 single cells simultaneously in the same subject using positron emission tomography (PET). The method relies on a new tracking algorithm (PEPT-EM) to push the cellular detection threshold to below 4 Bq/cell, and a streamlined workflow to reliably label single cells with over 50 Bq/cell of 18F-fluorodeoxyglucose (FDG). To demonstrate the potential of method, we tracked the fate of over 70 melanoma cells after intracardiac injection and found they primarily arrested in the small capillaries of the pulmonary, musculoskeletal, and digestive organ systems. This study bolsters the evolving potential of PET in offering unmatched insights into the earliest phases of cell trafficking in physiological and pathological processes and in cell-based therapies.

    View details for DOI 10.1101/2023.08.23.554536

    View details for PubMedID 37662335

    View details for PubMedCentralID PMC10473747

  • Radioluminescence from polymer dots based on thermally activated delayed fluorescence NANOSCALE ADVANCES Asanuma, D., Nguyen, H., Liu, Z., Tojo, S., Shigemitsu, H., Yamaji, M., Kawai, K., Mori, T., Kida, T., Pratx, G., Fujitsuka, M., Osakada, Y. 2023

    View details for DOI 10.1039/d3na00308f

    View details for Web of Science ID 000998986500001

  • Red, green, and blue radio-luminescent polymer dots doped with heteroleptic tris-cyclometalated iridium complexes. RSC advances Liu, Z., Nguyen, H. T., Asanuma, D., Tojo, S., Yamaji, M., Kawai, K., Pratx, G., Fujitsuka, M., Osakada, Y. 2023; 13 (22): 15126-15131


    In this study, we synthesized radioexcitable luminescent polymer dots (P-dots) doped with heteroleptic tris-cyclometalated iridium complexes that emit red, green, and blue light. We investigated the luminescence properties of these P-dots under X-ray and electron beam irradiation, revealing their potential as new organic scintillators.

    View details for DOI 10.1039/d3ra01216f

    View details for PubMedID 37207100

    View details for PubMedCentralID PMC10190261

  • Preclinical evaluation of 89Zr-Panitumumab for biology-guided radiotherapy. International journal of radiation oncology, biology, physics Natarajan, A., Khan, S., Liang, X., Nguyen, H., Das, N., Anders, D., Malik, N., Oderinde, O. M., Chin, F., Rosenthal, E., Pratx, G. 2023


    Biology-guided radiotherapy (BgRT) uses real-time line-of-response data from on-board PET detectors to guide beamlet delivery during therapeutic radiation. The current workflow requires 18F-fluorodeoxyglucose (FDG) administration daily prior to each treatment fraction. However, there are advantages to reducing the number of tracer injections by using a PET tracer with a longer decay time. In this context, we investigated 89Zr-Panitumumab (89Zr-Pan), an antibody PET tracer with a half-life of 78 hours that can be imaged for up to 9 days using PET.The BgRT workflow was evaluated pre-clinically in mouse colorectal cancer xenografts (HCT116) using small-animal PET/CT for imaging, and image-guided kilovoltage conformal irradiation for therapy. Mice (n=5 per group) received 7 MBq of 89Zr-Pan as a single dose 2 weeks after tumor induction, with or without fractionated radiation therapy (RT; 6×6.6 Gy) to the tumor region. The mice were imaged longitudinally to assess the kinetics of the tracer over 9 days. PET images were then analyzed to determine the stability of the PET signal in irradiated tumors over time.Mice in the treatment group experienced complete tumor regression, whereas those in the control group were sacrificed due to tumor burden. PET imaging of 89Zr-Pan showed well-delineated tumors with minimal background in both groups. On day 9 post-injection, tumor uptake of 89Zr-Pan was 7.2 ± 1.7 in the control group vs 5.2 ± 0.5 in the treatment group (mean %ID/g ± SD; P = 0.07), both significantly higher than FDG uptake (1.1 ± 0.5 %ID/g) 1 hour post injection. To assess BgRT feasibility, the clinical eligibility criteria was computed using human-equivalent uptake values that were extrapolated from preclinical PET data. Based on this semiquantitative analysis, BgRT may be feasible for 5 consecutive days following a single 740 MBq injection of 89Zr-Pan.This study indicates the potential of long-lived antibody-based PET tracers for guiding clinical BgRT.

    View details for DOI 10.1016/j.ijrobp.2023.01.007

    View details for PubMedID 36669541