LEP and non-alcoholic fatty liver: One year later, leptin, a vital biomarker of non-alcoholic fatty liver (NAFLD), was detected in PBS buffer and human serum by SVW (range 0.150–2500 pg/mL, LOD 0.036 pg/mL) on glassy carbon electrode (3 mm) modified with BP-black phosphorous (BP)/porous graphene (PG)/AuNPs/anti-leptin antibodies (20 × 103 pg/mL).