ENO2 and small cell lung carcinoma: Few examples from literature include GQD conjugated to antihuman immunoglobulin G antibody (mIgG) for sensing of immunoglobulin (Chen et al., 2018), glutathione functionalized GQD for sensing of ATP (Liu et al., 2013), N-functionalized GQD/Au nanoparticle/neuron-specific enolase antibodies (anti-NSE) bioconjugate for label free detection of small cell lung cancer (Kalkal et al., 2020), folic acid modifies/GQD/Au nanoparticle conjugate for ATP sensing (Zhang et al., 2019).