pH Monitoring of Tumor Microenvironment and Low Volume of Urine in Experimental Rats

The pH monitoring of the tumor microenvironment in vivo seems to be in fact complicated and technically quite challenging nowadays. Also the strategy of measuring urine pH of a little amount is not fully solved. Thus, the aim of our study was to monitor pH of urine samples (< 0.1 ml) and of tumor microenvironment of anesthetized rats in a minimal invasive way. The small urine volumes of rats or mice make pH measurements difficult, as standard pH electrodes usually need a minimal volume of several milliliters to function. The manual micromanipulator together with a needle-type housed pH microsensor offers a simple and effective way to do so. Our results show that pH of urine and tumor microenvironment was lower in tumor bearing rats compared to healthy subjects. The unique technology of pH microsensors could be a promising way to monitor the pH in many experimental designs and clinical praxis