2019 Volume 35 Issue 1 Pages 29-38
Applications of electrochemical biosensing for surveying intact cells and tissues have been focus of attention. Two experimental approaches have been used when performing amperometric measurements on biological cells, the stylus-type microelectrode probes and the electrode-integrated microdevices based on lithographic technologies. For the probe scanning approach, various types of microsensors were developed to monitor localized physical or chemical natures at a variety of surfaces in situ under wet conditions. Scanning electrochemical microscopy (SECM) has been applied for monitoring local oxygen, enzyme activity, and collection of transcripts. For the non-scanning type of approach, electrode array devices allow very rapid response, parallel monitoring, and multi-analyte assay. Sveral topics of on-chip-culture system were introduced especially concerning on gene expression monitoring by reporter system and reconstruction of in vivo-like nature by controlling microenvironments. Electrochemical reporter assay has been demonstrated to monitor the gene expression process of the gene-modified cultured cells. Long-term monitoring of cellular function of spheroids and three dimensionally-cultured cells were carried out by controlling microenvironments on the cellular chip.