Electrochemical type biosensors comprising resorcarenes

An electrode for the electrochemical detection of an analyte in a biological sample, wherein the electrode is a printed miniaturized carbon-based electrode comprising gold-coated nanoparticles, said nanoparticles comprising on their surface a compound of formula (II):

• wherein
• R1 is selected from hydrogen, alkyl, (CH2)nC(═O)OX, SO3X, PO(OX)2, (CH2)2OH, wherein n is an integer from 1 to 5;
• R2 is selected from hydrogen, [heterocycle]-C(═O)OX, CH2-[heterocycle]-C(═O)OX, CH2SO3X, CH2PO(OX)2;
• preferably said [heterocycle] is piperidine, pyrrolidine or piperazine;
• R3 is selected from
• a saturated linear aliphatic group containing sulfur of molecular formula (CH2)mSH or (CH2)mS(CH2)mCH3, wherein m is independently at each occurrence an integer from 5 to 11;
• or
• an aromatic group of molecular formula C6H4—SH, C4H3S, C6H4—N2Y;
• X is independently selected from positively charged atoms or groups comprising:
• Na+, K+, NH4+;
• Y is selected from negatively charged atoms or groups comprising:
• Cl−, BF4−.
• wherein said compound of formula (II) is non-covalently bound to at least one antibody able to detect said analyte.