Study of the in vitro degradation dynamics of the encapsulated PAL enzyme preparation in model biological fluids

The use of PAL in the phenylketonuria treatment is hindered by the lack of well-studied mechanisms and systems of targeted transport of enzyme preparations to certain organs and tissues (brain, liver, skin, muscle and connective tissues, blood cells). It is known that as a result of the incorporation of any pharmaceutical composition into the composition of the carrier, the pharmacokinetics and pharmacodynamics of the drug change. The essence of the enzyme stabilization process is to increase and maintain the catalytic activity of proteins, increase the duration of the catalytic action of enzymes on the substrate, change the optimal temperature and active acidity, increase productivity, as well as change the temporary effect of enzymes on the substrate in order to transform into an end product of the reaction. When stabilizing enzymes, encapsulation is preferred due to the fact that this method provides a high stability of enzymes under the influence of low temperature and low acidity of the environment, as well as the effect of harmful microflora and oxygen. It was proven that the degradation degree of capsules with PAL reaches 55–65% after 120 minutes of the experiment in distilled water. The maximum degradation of the encapsulated form of the PAL enzyme preparation (the proportion of capsule weight loss is 90–98%) occurs in model biorelevant media that mimic intestinal juice: SIF and FaSSIF. It should be noted that the rate of capsule degradation is higher in the simulated intestinal fluid (SIF) without pancreatin (the proportion of capsule weight loss is 92–98% after 15 minutes of the experiment) compared to the fasted state simulated intestinal fluid (FaSSIF) (the proportion of capsule weight loss is 90-97 % after 30 min of experiment).