i am doing total phenol by FC method
i got R2 value 0.178 when dilution intervals are 150micro liters of Gallic acid microliter/ml
and FC 150 microliter with 7.5% Na2CO3 500 microliter
repeated with GA with 200 microliter dilution interval then R2 value 0.312
repeated with GA with 300 microliter dilution interval then R2 value 0.208
where i am doing wrong please suggest