Detection of cytokines using biosensor based on functionalized nanocarriers growth on gold electrode

Nowadays , it is well established that the performance of biosensors depends greatly on the influence imposed on biomolecules by immobilisation.In this context, the use of nanomaterials for the construction of biosensing... [ view full abstract ]

Nowadays , it is well established that the performance of biosensors depends greatly on the influence imposed on biomolecules by immobilisation.In this context, the use of nanomaterials for the construction of biosensing devices constitutes one of the most interesting approaches. Application of gold nanoparticules in biosensing has attracted considerable attention because gold nanoparticules (GNPs) are the most compatible nanomaterial for preparation of engineered nanoplatforms in smart sensing devices beside the fact that they have interesting electronic , optical ,thermal and catalytic properties . however, their application is obviously affected by many conditions, such as the size , the shape , the roughness of the substrate and the density of the particules on the surface . In this work we will present some phenomena noticed linked to the impact of gold Np characteristics’s on the sensing of cytokine. The cytokine studied for this purpose were : IL1β, IL-10 and IL-6 , using a spectroscopy of impedance for the detection of their corresponding antigens in the range of 1 pg/ml to 30 pg/ml. Effect such as antibodies/Np ratio on the sensing was noticed and this has affected really the sensibility of the biosensor. The gold nanoparticules were electrochemicaly synthesized from KAu(CN)2 diluted into phosphate buffer (PBS) at acidic bath using the chronoamperometric.
The sensitivity of Au-nanoparticles modified biosensor was more pronounced than gold biosensor. The limit of detection (LOD) of the gold biosensor was 1.5 pg/mL. The plot was linear (r=0.9968) within the range of 1-15 pg/ml. Whist the LOD of Au-nanoparticles modified biosensor was 1 pg/mL. The sensitivity of this modified biosensor was enhanced by the introduction of gold nanoparticules as electrolyte/gold interface has been increased. This biosensor is very promising for a rapid and sensitive detection.