GSTM1 and diabetes mellitus: The median (range) HbA1c concentrations measured by POCT-HbA1cMWCNTs/AuNPs in DM and non-DM patients were 0.64 (0.36–0.93) and 0.48 (0.22–0.64) g/dL, respectively [corresponding to 7.19 (5.18–11.89) and 6.03 (4.10–6.40)% of total Hb, respectively].