Lactate biosensor fabrication using a chitosan and cross linker configuration realised solution mediation(K3Fe (CN)6) with lactate linear range9.9 × 10−4 to 5.66×10−3 M, sensitivity 1.44×10−3C cm−2 mM−1 and LOD of 0.54 mM. Further development involved use of the heterocyclic quinoid species 1,10-phenanthroline-5,6-dione which acted as a proton and electron acceptor in relation to FADH2 cofactor regeneration. Graphite ink was formulated and utilis ed as an underlying conductive layer for LOx enzyme immobilisation and enzymatic polymerisation of 1,10-phenanthroline-5,6-dioneata GC electrode, resulting in a linear range of 0.74 -2.44×10−3 M, sensitivity of4.11×10−4C cm−2 mM−1 and LODof0.06mM.Scanning electron and electrochemical scanning microscopy realised surface characterisation of the enzyme layers.