Optical measurement probe

An arrangement for detecting measurement values of a measurand of a measuring fluid, the arrangement comprising:

• an optical measurement probe including:
• a probe housing having at least one immersion region configured to be immersed in the measuring fluid;
• an indicator chamber defined in the probe housing and closed on a side thereof in the immersion region of the probe housing by a membrane, wherein an indicator is contained in the indicator chamber, wherein the indicator comprises an aggregation-induced emission active (AIE-active) substance dissolved in a primary solvent to form an indicator solution or indicator gel, which AIE-active substance is formed from species whose luminescence efficiency is increased via formation of aggregates containing the species, wherein the primary solvent is water or an ionic liquid
• wherein the indicator includes at least one auxiliary substance that increases the solubility of the AIE-active substance and/or decreases a boiling temperature of the indicator, wherein the at least one auxiliary substance is different than the primary solvent and is a compound having a molecular weight of greater than 200 g/mol;
• a radiation source disposed in the probe housing and configured to emit radiation into the indicator chamber as to generate radiation in the indicator;
• and
• a radiation receiver disposed in the probe housing and configured to detect the generated radiation emitted from the indicator within the chamber,
• wherein the measurand represents a concentration of an analyte in the measuring medium determined from the generated radiation emitted from the indicator, which is detected by the radiation receiver,
• wherein the membrane is permeable to the analyte, and wherein the membrane is impermeable to the AIE-active substance of the indicator and to the at least one auxiliary substance;
• and
• a superordinate unit in communication with the measurement probe, wherein the measurement probe and the superordinate unit are coupled with one another via a releasable connection, the connection configured to transmit energy uni-directionally from the superordinate unit to the measurement probe.

An optical measurement probe for detecting measurement values of a measurand of a measuring fluid, comprising:

• a probe housing having at least one immersion region configured to be immersed in the measuring fluid;
• an indicator chamber defined in the probe housing and closed on a side thereof in the immersion region of the probe housing by a membrane, wherein an indicator is contained in the indicator chamber, wherein the indicator comprises an aggregation-induced emission active (AIE-active) substance dissolved in a primary solvent to form an indicator solution or indicator gel, which AIE-active substance is formed from species whose luminescence efficiency is increased via formation of aggregates containing the species, wherein the primary solvent is water or an ionic liquid,
• wherein the indicator includes at least one auxiliary substance that increases the solubility of the AIE-active substance and/or decreases a boiling temperature of the indicator, wherein the at least one auxiliary substance is different than the primary solvent and is a compound having a molecular weight of greater than 200 g/mol;
• a radiation source disposed in the probe housing and configured to emit radiation into the indicator chamber as to generate radiation in the indicator;
• and
• a radiation receiver disposed in the probe housing and configured detect the generated radiation emitted from the indicator within the chamber,
• wherein the measurand represents a concentration of an analyte in the measuring medium determined from the generated radiation emitted from the indicator, which is detected by the radiation receiver,
• wherein the membrane is permeable to the analyte, and wherein the membrane is impermeable to the AIE-active substance of the indicator and to the at least one auxiliary substance,
• wherein materials comprising the membrane and/or the indicator chamber are functionalized with functional groups that suppress aggregation of the A1E-active substance at an interface between the membrane and the indicator contained in the indicator chamber and/or between the indicator chamber and the indicator.