The stability of l-alanyl-l-tyrosine can also be improved from aspects such as crystal form regulation and packaging material selection. The specific methods are as follows:
I. Crystal Form Regulation
Screening of Stable Crystal Forms: l-alanyl-l-tyrosine may exist in multiple crystal forms, and the stabilities of different crystal forms vary. Through crystal form screening experiments, such as the solvent evaporation method and the cooling crystallization method, a crystal form with higher stability can be found for the production of pharmaceutical preparations. For example, studies have found that a specific crystal form of l-alanyl-l-tyrosine has significantly better stability than other crystal forms under high-temperature and high-humidity conditions.
Inhibition of Crystal Form Transformation: During the production and storage of pharmaceutical preparations, it is necessary to prevent the transformation of stable crystal forms into unstable crystal forms. This can be achieved by controlling process conditions and adding crystal form stabilizers. For example, during the crystallization process, precisely control parameters such as temperature and stirring speed to make the crystal growth uniform and reduce the possibility of crystal form transformation. At the same time, add an appropriate amount of crystal form stabilizers, such as certain polymers or surfactants, which can be adsorbed on the surface of the crystals to prevent the occurrence of crystal form transformation.
II. Packaging Material Selection
Materials with Good Barrier Properties: Select packaging materials with good barrier properties, which can effectively prevent the influence of external factors such as oxygen, moisture, and light on alanyl-L-tyrosine. For example, use multi-layer composite packaging materials, which include an aluminum foil layer, a polyester layer, etc. These materials have excellent oxygen barrier, water barrier, and light shielding properties, which can extend the shelf life of the drug.
Appropriate Packaging Forms: According to the properties and usage requirements of the drug, select appropriate packaging forms. For injectable preparations, ampoules or pre-filled syringes can be used for packaging to ensure the stability of the drug before use. For oral preparations, aluminum-plastic blister packaging or plastic bottle packaging can be used, and desiccants can be placed inside the packaging to prevent the drug from getting damp and deteriorating.
III. Optimization of Pharmaceutical Formulations
Preparation of Microspheres or Nanoparticles: Preparing l-alanyl-l-tyrosine into microsphere or nanoparticle formulations can increase the stability of the drug. By using appropriate preparation methods, such as the emulsion-solvent evaporation method and the spray drying method, the drug is encapsulated in a polymer carrier. This can reduce the contact between the drug and the external environment. At the same time, the polymer carrier can also play a role in protecting the drug and prevent the drug from being degraded during storage and release in the body.
Development of Sustained-Release and Controlled-Release Formulations: Sustained-release and controlled-release formulations can make the drug release slowly and continuously in the body, reducing the exposure time of the drug in the gastrointestinal tract, thereby improving the stability of the drug. For example, use a matrix-type sustained-release and controlled-release formulation. Mix l-alanyl-l-tyrosine with polymer materials to prepare tablets or capsules, and the drug is slowly released through the pores of the polymer materials, avoiding the rapid degradation of the drug in the gastrointestinal tract.
