Exploiting second-order advantage for simultaneous biosensing of romidepsin and vorinostat in the presence of belinostat as uncalibrated interference in human serum samples

In this work, a novel, ultra-sensitive, selective, and multi-electrochemical techniques biosensor was fabricated for simultaneous determination of romidepsin (RD) and vorinostat (VN) in the presence of belinostat (BS) as uncalibrated interference in human serum samples. A glassy carbon electrode (GCE) was modified with chitosanionic liquid (CS-IL) which was used as a platform to immobilize histone deacetylase (HDAC) by the use of glutaraldehyde. The RD and VN as inhibitors of the HDAC were trapped by the HDAC onto the biosensor surface which didn't show any response at the surface of the CS-IL/GCE. In order to simultaneous biosensing of RD and VN, the biosensor was immersed into a probe solution to get a response from the biosensor. By individual immersion of the biosensor into RD and VN solutions different steric hindrances were occurred at the biosensor surface which caused generation of two different responses from the biosensor. The biosensor responses were individually calibrated and used to develop second-order calibration models to support the biosensor for simultaneous determination of RD and VN. Second-order hydrodynamic square wave voltammetric (HSWV) data were generated and modeled by PARAFAC2, MCR-ALS, PARASIAS, and U-PCA/RBL to find the best method to couple with outputs of the biosensor. The results confirmed the best performance for the biosensor- U-PCA/RBL for simultaneous determination of RD and VN in the presence of BS in artificial human serum samples. The biosensor-U-PCA/RBL combinatorial method was also successful in simultaneous determination of RD and VN in the presence of BS in real human serum samples with a comparable performance with HPLC as the reference method.