A lactate needle-type biosensor for in vivo detection in muscular tissues

As an alternative method for whole blood lactate monitoring in clinical and sports medicine, a needle-type lactate biosensor [Z. Lin, W. Qiao, M. Wu, Anal. Lett., 25(7) (1992) 1171] is designed here for in vivo detection of lactate in muscular tissues. It was constructed by a stainless steel needle, with the surface modified by a polymer material for the enzyme (lactate oxidase, LOD, hydrogen peroxide oxidoreductase, HPO) immobilization. The influences of pH and temperature were discussed. It can determine the substrate ranging from 4.8×10−6 to 3.2×10−3 mol/l, with the response time of 3 min. The possible interference of the ascorbic acid, urea, glucose, etc., for in vivo detection was studied. The biosensor was used in the detection of the lactate in vivo in muscular tissues of the K.M. mice and different concentrations of lactate were obtained for about 10 min before and after exercise.