2A-O1-1000 PDF
Development of Laser Ionization Techniques for Pharmacokinetic Analysis of Cancer Drugs using Imaging Mass Spectrometry
Recently, the combined therapy using chemotherapy and Photodynamic therapy (PDT) has been proposed. The distributions of the anticancer drug and the photosensitizer are important to evaluate the efficacy of the combined therapy. We are investigating IMS to simultaneously observe the distributions of anticancer drug and photosensitizer administered into cancer cells. The purpose of this research is to enhance the detection sensitivity for the anticancer drugs, anticancer drug and photosensitizer, protoporphyrinIX by improving the ionization assisting reagents. Mass spectra were obtained with a time-of-flight mass spectrometer equipped with a Nd:YAG laser at a wavelength of 355 nm. By mixing zeolite (NaY5.6) with 6-aza-2-thiothymine known as an organic matrix for matrix-assisted laser desorption/ionization at the same weight ratio, the signal intensity of Sodium adduct ion of docetaxel at a concentration of 100 μM increased to about 13 times. Moreover, docetaxel at a concentration of 1 μM was detected using the zeolite matrix and was not detected using 6-aza-2-thiothymine only. Then docetaxel and PpIX administered into the human prostate cancer cells PC-3 were detected using the zeolite matrix in the droplet method and CHCA in the spray method, respectively.