ArticleMagnetic resonance in medicine2019
Free-base porphyrins as CEST MRI contrast agents with highly upfield shifted labile protons.
Article in Magnetic resonance in medicine, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 17 papers.
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Who cites it
17 citing papers in PubMed, 21 citations in OpenAlex.
- CEST MRI: Translational prospects for intervertebral disc degeneration - from basic research to clinical applications.Journal of orthopaedic translation · 2026Review
- Protamine-1 encoded recombinant adeno-associated virus for enhanced brain magnetic resonance imaging.Magnetic resonance letters · 2026Article
- Quantitative MRI Pharmacokinetic Modeling and MALDI Mass Spectrometry Imaging Biodistribution of a pH Mapping MRI Contrast Agent.Theranostics · 2026Article
- Novel non‑metal‑based contrast agents for MR imaging: Emerging approaches and clinical perspectives (Review).International journal of oncology · 2025Review
- Synthesis, Characterization, Magnetic Properties, and Applications of Carbon Dots as Diamagnetic Chemical Exchange Saturation Transfer Magnetic Resonance Imaging Contrast Agents: A Review.Nanomaterials (Basel, Switzerland) · 2025Review
- Going Above and Beyond: Achieving High Contrast and Higher Offset through Carbon Dot-Based diaCEST MRI Contrast Agent.Chemical & biomedical imaging · 2025Article
- MRI detection of free-contrast agent nanoparticles.Magnetic resonance in medicine · 2025Article
- Design Chemical Exchange Saturation Transfer Contrast Agents and Nanocarriers for Imaging Proton ExchangeACS nano · 2024Review
- Intramolecular Hydrogen Bonding Based CEST MRI Contrast Agents As an Emerging Design Strategy: A Mini-Review.ACS omega · 2024Review
- Exploring the potential of the novel imidazole-4,5-dicarboxyamide chemical exchange saturation transfer scaffold for pH and perfusion imaging.NMR in biomedicine · 2023Article
- Acyl Hydrazides and Acyl Hydrazones as High-Performance Chemical Exchange Saturation Transfer MRI Contrast Agents.Pharmaceuticals (Basel, Switzerland) · 2023Article
- Structural and functional imaging of brains.Science China. Chemistry · 2023Review
- Preparation of Hydrothermal Carbon Quantum Dots as a Contrast Amplifying Technique for the diaCEST MRI Contrast Agents.ACS omega · 2022Article
- Coloring ultrasensitive MRI with tunable metal-organic frameworks.Chemical science · 2021Article
- Paracetamol and other acetanilide analogs as inter-molecular hydrogen bonding assisted diamagnetic CEST MRI contrast agents.RSC advances · 2021Article
- Repurposing Clinical Agents for Chemical Exchange Saturation Transfer Magnetic Resonance Imaging: Current Status and Future Perspectives.Pharmaceuticals (Basel, Switzerland) · 2020Review
- Amplified detection of phosphocreatine and creatine after supplementation using CEST MRI at high and ultrahigh magnetic fields.Journal of magnetic resonance (San Diego, Calif. : 1997) · 2020Article
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Authors and funding
11 authors at 2 institutions in 2 countries.
Funding
Abstract
purposeCEST has become a preeminent technology for the rapid detection and grading of tumors, securing its widespread use in both laboratory and clinical research. However, many existing CEST MRI agents exhibit a sensitivity limitation due to small chemical shifts between their exchangeable protons and water. We propose a new group of CEST MRI agents, free-base porphyrins and chlorin, with large exchangeable proton chemical shifts from water for enhanced detection.
methodsTo test these newly identified CEST agents, we acquired a series of Z-spectra at multiple pH values and saturation field strengths to determine their CEST properties. The data were analyzed using the quantifying exchange using saturation power method to quantify exchange rates. After identifying several promising candidates, a porphyrin solution was injected into tumor-bearing mice, and MR images were acquired to assess detection feasibility in vivo.
resultsBased on the Z-spectra, the inner nitrogen protons in free-base porphyrins and chlorin resonate from -8 to -13.5 ppm from water, far shifted from the majority of endogenous metabolites (0-4 ppm) and Nuclear Overhauser enhancements (-1 to -3.5 ppm) and far removed from the salicylates, imidazoles, and anthranillates (5-12 ppm). The exchange rates are sufficiently slow to intermediate (500-9000 s
conclusionThese results highlight the capabilities of free-base porphyrins and chlorin as highly upfield CEST MRI agents and provide a new scaffold that can be integrated into a variety of diagnostic or theranostic agents for biomedical applications.
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Registered trials
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