Study of the membrane permeability of a paramagnetic metal complex on single cells by NMR microscopy.
A new procedure has been developed for investigating the ability of paramagnetic metal complexes to penetrate the plasma membrane of eukaryotic cells without decomposition. Defolliculated Xenopus laevis oocytes formed the biological system to test N,N-ethylenebis-(1,5,5-trimethyltetramic-acid-3-acetiminato) copper (II). An increase of the signal intensities in spin-echo (SE) images of oocytes treated with the tested substance indicated that the complex was able to penetrate biological membranes due to the arrangement of hydrophobic and hydrophilic groups within the ligand. In contrast, the treatment with the commonly used contrast agent gadolinium-DTPA/dimeglumine did not enhance the signal intensity in NMR images of oocytes after time periods of exposure comparable to those used for the copper complex. After microinjection into Xenopus oocytes the copper complex was released into the extracellular medium without degradation, as shown by HPLC measurements.
Institute of Analytical Chemistry, Humboldt University of Berlin, Germany.
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Päuser
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Keller
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Zschunke
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Mügge
D000818:Animals; D002463:Cell Membrane Permeability; D002851:Chromatography, High Pressure Liquid; D003287:Contrast Media / Q000493:pharmacokinetics; D009682:Magnetic Resonance Spectroscopy; D008853:Microscopy; D009865:Oocytes / Q000166:cytology / Q000378:metabolism; D009942:Organometallic Compounds / Q000493:pharmacokinetics*; D014981:Xenopus
D003287:Contrast Media; C081509:N,N-ethylenebis(1,5,5-trimethyltetramic acid-3-acetiminato)copper(II); D009942:Organometallic Compounds