courtesy of Surface Measurement Systems

This study investigates the chemical degradation and dehydration behaviours of pharmaceutical compounds, acetylsalicylic acid (ASA) and citric acid monohydrate, used in drug formulation, stability, and drug delivery systems. The combination of DVS and Raman spectroscopy reveals changes during ASA degradation, influenced by humidity and temperature. Analysing the process of dehydration of citric acid monohydrate is important when understanding drug release mechanisms. This has been shown to be affected by temperature and humidity, with higher humidity necessitating elevated temperatures to produce its anhydrous form. Understanding the changes and kinetics involved in these processes can influence decisions in pharmaceutical design, enhancing drug efficacy and shelf-life.

Introduction

During pharmaceutical development, ensuring the stability and efficacy of drug formulations is of paramount importance. For many materials, chemical and physical transitions can be influenced by the amount of water vapour surrounding the sample. Water vapor can associate with a solid in various ways: adsorption or chemisorption onto the surface, absorbing into the bulk, acting as a plasticizing agent, or chemically reacting with the solid. Measuring temperature dependent stability is important as it impacts physical, chemical, and biological efficacy. Understanding the complex interplay between moisture and temperature in pharmaceutical compounds is essential for mitigating risks caused by transformations and degradation, potentially rendering the pharmaceutical ingredient inactive [1]. Water vapor's multifaceted interactions with pharmaceutical ingredients underscore the need for analytical techniques capable of measuring these processes.

This study uses a combination of water sorption measured using the Dynamic Vapour Sorption technique (DVS) and Raman spectroscopy to detect, monitor, and measure humidity and temperature induced changes in pharmaceutical ingredients. This approach enables researchers to explain chemical changes occurring in drug formulations in response to varying moisture levels. This interdisciplinary approach not only enhances our understanding of the fundamental mechanisms underlying changes, but also facilitates the development of robust strategies for formulation design, storage, and packaging.

 

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