Why Is Sample Pretreatment Necessary?
Some samples can seriously interfere with the biochemical reaction of the Limulus Amebocyte Lysate (LAL) test and may even prevent the reaction from occurring. In such cases, special sample pretreatment procedures are required before testing.
Dilution Method
A considerable proportion of interfering substances only exert their effects at certain concentrations. Therefore, appropriately diluting the sample may reduce or eliminate the interference, allowing the sample to be tested using the routine procedure. Examples include injections containing mannitol, gentamicin, human serum albumin, sodium heparin, and vitamin C.
Heating Method
Some interfering substances are heat-labile. Holding the sample at an appropriate temperature for a specified period of time can inactivate or reduce these interfering factors, after which the sample can be tested using the routine procedure. This approach may be applicable to certain blood products and biological products.
pH Adjustment Method
Some samples have a pH that is too high or too low, and the pH buffer in the LAL reagent may be insufficient to bring the reaction mixture within the appropriate range. In such cases, the sample pH ```