Graphene based filters represent an innovative solution for contaminant or pollutant filtering that is able to combine very good filtering capability and small size scale. Recent researches have proposed to consider the realization of these filters with graphene nanoplatelets. The main advantages of this technological solution are associated to the simple and cheap production process and the possibility to monitoring their status, by measuring their electrical impedance during the adsorption of the pollutant.In this paper, the improvement of an innovative impedance measuring technique is proposed in order to increase the sensitivity of the monitoring process and the reliability of the filter health state classification. It is based on a multi-frequency excitation of the filter during the electrical impedance measurement and the analysis of the impedance behavior at the different frequencies. It allows observing in real-time the different phases of life of the filter: clean, polluted, saturated and regenerated. The proposed techniques is here successfully validated with reference to filters absorbing acetonitrile. The result could be of interest for potential applications for the realization of smart sensing device for predictive maintenance of the filters and air quality remediation. © 2020 IEEE.