is there an equipment (a method) to measure tissue pH from outside (e.g. percutaneous) ?

Although often overlooked, passive mechanisms can lead to significant accumulation or restriction of drugs to intracellular sites of drug action. These mechanisms include lipoidal diffusion of ionized species and pH partitioning according to the electrochemical potential and to pH gradients that exist across subcellular compartments, respectively....

The first tissue pH electrode is described and illustrated and notable features are commented on. Calibration procedure is discussed particularly concerning the need for temperature control. Experience with early examples of the tissue electrode is described and its performance with an independent pH monitoring and recording system assessed. Attent...