(99m)Tc-DTPA Uptake and Electrical Impedance Measurements in Verification of In Vivo Electropermeabilization Efficiency in Rat Muscle.

Research output: Contribution to journalArticle


Objective: In vivo electropermeabilization of cell membranes in rat muscle tissue cause a significant decrease of the electrical impedance, in the frequency region of 1-10 kHz. We aimed to study how the Tc-99m-DTPA uptake in the electropermeabilized region correlates to the change of admittance Y = 1/absZ, where Z is the measured impedance. Methods: The electropermeabilization was performed in vivo by applying high-voltage (0.5-2 kV) short (0.1-2 ms) pulses through gold-plated needle electrodes in skeletal muscle. The impedance was measured before and after each electropermeabilization pulse. The uptake of Tc-99m-DTPA uptake in the electropermeabilized region was measured after 6 and 24 hours with a gamma camera. Results: The pulse shape (square and exponential), duration, and amplitude of the applied electric field were varied, and electropermeabilization efficiency was evaluated using the various measurement modalities. Good correlations were found (correlation coefficient approximate to 0.9) between the Tc-99m-DTPA uptake in the electropermeabilized and control "region of interest" the admittance ratio Y (post-treatment)/Y (pretreatment), and charge displacement parameter Q. Conclusion: The electrical impedance measurements method can be utilized in clinical settings to verify the efficiency of electropermeabilization applied to chemotherapy and to power RNAi (RNA-interference) and DNA-plasmid transfection in vaccination, immunization, and gene-therapy.


Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Cancer and Oncology


  • admittance, electrical impedance, electroporation, cell membranes, Tc-99m-DTPA, electropermeabilization, gamma camera, clinical dosimetry, chemotherapy, in vivo transfection, RNAi (RNA-interference), DNA-plasmid transfection, vaccination, gene therapy
Original languageEnglish
Pages (from-to)623-635
JournalCancer Biotherapy & Radiopharmaceuticals
Issue number6
Publication statusPublished - 2006
Publication categoryResearch