Measurement unit for an ion-sensitive solid-state electrode, that serves to measure pH in a measurement solution, with a layered structure including an ion-sensitive glass layer with a first ring-shaped contact surface, an electrically conducting layer that directly or via at least one intermediate layer adheres to the ion-sensitive glass layer, and a substrate that adheres to the electrically conducting layer and is provided with a second ring-shaped contact surface; and with a holding member that is provided with a first ring-shaped sealing surface, a second ring-shaped sealing surface, and an annular section; wherein the first ring-shaped sealing surface is sealingly connected to the first ring-shaped contact surface, wherein the second ring-shaped sealing surface is connected to the second ring-shaped contact surface of the substrate, and wherein the first and second ring-shaped sealing surfaces of the holding member are sealingly connected by the annular section.