Stabilization of horseradish peroxidase (HRP) for use in immunochemical sensors

摘要

Abstract: For biosensors it is very useful to work with enzymes which have a constant activity over a long period of time. For that purpose we tested 3,3',5,5'-tetramethylbenzidine (TMB), luminol, argon saturation of the buffer, bovine serum albumin (BSA) and Tween 20 on their stabilizing effect on the enzyme horseradish peroxidase. We found that TMB and luminol stabilize the enzyme very efficiently. Storing the solutions in the dark, even at stabilizer concentrations below 0.1 mM no significant loss of activity was observed during 12 weeks. At daylight the activity decreased with this stabilizers to 80% of initial activity within six weeks. In the dark no argon saturation of the buffer is necessary. On the other side, if the samples are stored at daylight, deactivation of the enzyme is strongly reduced by saturation of the buffer with argon. No stabilizing effect was observed with additives like BSA or Tween 20, which are often proposed as stabilizers in literature. The stabilized enzyme could be used for colorimetric or chemiluminescent detection independent from the stabilizing reagent used. We are now able to ensure high activity for the enzyme label HRP at room temperature over several weeks up to three months. !11