ABSTRACT
The aim of this research is to study the effect of different storage conditions [different temperatures and formalin preservation] on the stability of amitriptyline and fluphenazine in some biological samples. The LD[50] of amitriptyline and fluphenazine were administrated orally to rabbits which were sacrificed two hours after administration of the drugs. The tissues were stored at different conditions for six months. U.V. Spectrophotometer was used for estimation of the drugs at different periods. The results revealed that both amitriptyline and fluphenazine were rapidly declined in samples stored at room temperature [25 - 38°C]. It could not be detected in brain and liver samples at the end of three weeks, in the kidney at the end of four weeks and in plasma at the end of six weeks. While fluphenazine could not be detected in the brain at the end of three weeks, in the kidney and liver at the end of four weeks and in the plasma at the end of six weeks. At fridge temperature [5°C], amitriptyline could not be detected in brain and liver at the end of four weeks, in kidney samples at the end of six weeks. While fluphenazine could not be detected in brain at the end of four weeks, in kidney and liver at the end of six weeks, in plasma both of them couldn't be detected at the end of eight weeks. At freezer temperature [-20°C], amitriptyline could be detected up to the end of six months of the storage in the different samples with different relative recovery percent 80%, 75%, 69.57%, and 63.00% [for plasma, kidney, brain and liver samples respectively]. While fluphenazine could be detected up to the end four months of the storage in the plasma, kidney, and liver with different relative recovery percent [19.77%, 13.88%, and 11.56% respectively]. In brain fluphenazine could be detected up to the end of twelve weeks with a relative recovery percent of 15.76%. In samples preserved in 10% formalin solution, amitriptyline could be detected up to the end of six months of the storage in the different samples with high relative recovery percents [90.81%, 90.18%, 87.84% and 86.14%] for the kidney, plasma, brain, and liver respectively. While fluphenazine could not be detected in brain samples at the end of six weeks. It could not be detected in liver, kidney, and plasma at the end of eight weeks of the storage. In conclusion amitriptyline is stable in tissues stored at freezer [-20°C] and that preserved in formalin solution. While fluphenazine is stable in tissues stored at freezer [-20°C] for sometime, but it is not stable in the samples stored at room temperature, fridge temperature, and in samples preserved in formalin solution