Giorgia Sciutto

Miniaturized biosensors for the detection of aged proteins in paint samples

Giorgia Sciutto, M. Zangheri, L. Anfossi, M. Guardigli, S. Prati, M. Mirasoli, F. Di Nardo, C. Baggiani, R. Mazzeo, A. Roda

Department of Chemistry- University of Bologna, Via Guaccimanni 42, 48121 Ravenna

Immunological approaches have been proposed several years ago as powerful tools for the detection of aged proteins. In the last decades, performances of immunochemical approaches have been investigated by optimizing different systems for the identification of proteins in artistic samples. Exploiting the potentials of the chemiluminescent (CL) detection, we have developed single or multiplexed localization of proteins in artwork samples.

More recently, we proposed portable and reliable analytical systems to be used on site by not specialized operators, supporting restoration campaigns at a limited cost. The devices are based the lateral flow immunoassay (LFIA) technology to obtain maximum user-friendliness, as the operator does not need to manipulate any reagent.

Multiplex LFIA biosensors allowed the simultaneous detection of collagen and ovalbumin, exploiting an AuNP colorimetric approach or a CL reaction catalyzed by enzymes for the detection. The detectability of the chemiluminescent system was two times higher than that of the colorimetric system. On the other hand, the CL-LFIA method required a multistep analytical protocol with sequential addition of sample and reagents. To simplify the procedure, we designed a disposable analytical cartridge containing the LFIA strip and all the necessary reagents. Thus, only the sample must be added. In addition, to keep the device small, we used a “contact imaging” configuration, in which the CL signal is conveyed to the CCD sensor by a fiber optic faceplate. These results point to the enormous potential of these cheap, easy-to-use, and minimally invasive diagnostic tools for conservators.