A do-it-yourself electrochemical cell based on pencil leads and transparency sheets: application to the enzymatic determination of histamine

This research received financial support from the European Union (FEDER funds through COMPETE POCI-01-0145-FEDER-030735) and National Funds (“Fundaçao para a Ciencia e a Tecnologia” (FCT)) through the project PTDC/QUI-QAN/30735/2017 - TracAllerSens. This work was also financially supported by Portuguese national funds through projects UIDB/50006/2020 and UIDP/50006/2020 from FCT/ “Ministério da Ciencia, Tecnologia e Ensino Superior” (MCTES). E. Costa-Rama thanks the support of the grant “Beatriz Galindo” (BG20/00027) funded by the “Ministerio de Universidades” of the Spanish Government. R. Torre thanks FCT and the European Social Fund (ESF), through the “Programa Operacional Capital Humano” (POCH), for her PhD grant (SFRH/BD/143753/2019).