Sensors for the determination of organometallic compounds

Sensors for the determination of organometallic compounds, e.g. n-butyllithium, comprise the following elements: a)an inorganic, organic or polymeric support, insoluble in the sample to analyze b)an indicator which reversibly reacts with the organometallic compound and whose reaction product gives a characteristic absorption, reflection or emission band in the range 150-15000nm, e.g. 1,10-phenanthroline and derivatives, triphenylmethane, or N-Ä2-(4-hydroxybenzyl)phenylÜ-2,2-dimethylpropanamide, and which is physically trapped, adsorbed, absorbed, dissolved or chemically linked in an electrostatic or covalent way to the support c)an optical sensor which measures the absorption, reflection or emission of the functionalized support at the characteristic wavelength and transforms it in the concentration of the organometallic present in the solution. Also described is the method for the determination of the concentration of organometallic compounds by the on line use of a sensor in anionic polymerizations.