RETRACTED: Graphene quantum dots decorated CdS doped graphene oxide sheets in dual action mode: As initiator and platform for designing of nimesulide imprinted polymer

Santanu Patra, Ekta Roy, Raksha Choudhary, Ashutosh Tiwari, Rashmi Madhuri, Prashant K. Sharma

The present work describes the preparation of a nanohybrid by a combination of the 2D graphene sheet and 0D graphene quantum dots (GQDs). The GQDs were prepared from natural green precursors i.e. carrot juice by the one-step hydrothermal process. To get the maximum fluorescence property from nanohybrid, the graphene sheets were chemically doped with cadmium sulphide (CdS). The as prepared nanohybrid was characterized by means of X-ray diffraction analysis (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), fluorescence and UV-vis spectroscopic techniques. The nanohybrid was further modified to design a nano-iniferter, which shows dual property i.e. works as polymerization initiator as well as provides platform for synthesis of the nimesulide-imprinted polymer. For designing of imprinted polymer two biocompatible monomers (cystine monomer and N-vinyl caprolactam) were used, which provides biodegradability to the polymer matrix. The imprinted polymer shows a very good selectivity towards the detection of nimesulide with a limit of detection as low as 6.65ngL(-1) (S/N=3). The sensor was also applied for the detection of nimesulide in real samples like human blood serum, plasma and urine samples as well as some pharmaceutical tablets.