Abstract
Biological membranes are important interfaces that control the movement of substances and information between cells. In order to develop efficient medical care and drugs, it is necessary to study microscale distribution behavior of drugs such as membrane permeability and intra–tissue diffusion, especially in the field of drug delivery system (DDS). Therefore, ultra–sensitive bioanalysis methods have been developed in which trace sample at the single cell level is collected and measured using nanoelectrospray ionization (nanoESI)–mass spectrometry (MS). While nanoESI–MS can detect drugs contained in trace samples with high sensitivity, it has the disadvantage of being unable to remove contaminant components such as salts, resulting in ionization suppression and poor quantitative performance. To solve this problem, we have developed a calibration method for accurate quantification in contaminated salts and a separation method by removing biological matrix. In this review, two of my research achievements for the trace drug analysis are summarized.
