3.5. Interaction of the interfering species
As we know, human blood serum contains many more bio
components like salts, amino acids, carbohydrates, lipids etc.,
those can interfere with cholesterol detection and hamper the
selectivity of the biosensor. Therefore, we studied a wide range of
response in DPV for the species which can interfere with the
detection process of cholesterol in the blood serum. It is quite
evident from Fig. 4 that salts like NaCl, KCl and MgCl2; carbohydrates
and amino acids like glucose, glycine etc. showed negligible
interference even at the concentration of 2 mM, except tryptophan.
Anionic surfactant like Sodium Dodecyl Sulfate (SDS)
showed minute interference in the system, compared to cholesterol
detected for only 30 mM concentration. Similarly, few hydrophobic
drugs (lidocaine, chloropramine, quinine, quinidine and
piroxicam) were checked for their interference with cholesterol.
Results obtained showed very little interference for 2 mM drug
concentrations against 30 mM cholesterol concentration.