Moisture Content Determination

As a part of routine, regular testing to ensure the quality of drug products, moisture content measurement is an important quality control testing in the manufacture of pharmaceuticals, from checking raw materials and in-process control of tablets and capsules to quality checks of finished drugs as part of the pharmacopeial testing procedure.

BOC Sciences has extensive experience in weighing and moisture analysis, and we offer validated drying methods for some of the most common pharmaceutical samples and excipients, so you can be sure that your results will be consistent with official methods. Our team of experts are proud of providing fast, accurate and reliable measurements using a variety of tools and expertise to support and enhance your pharmaceutical moisture analysis.

Figure 1. Titer determination in Karl Fischer titration. (Alyson Lanciki. 2020)

Our Technologies

Karl Fischer (KF) Titration Method

The Karl Fischer titration method is an excellent choice when accurate, rapid and selective determination of the water content in pharmaceutical products is required. Nowadays, Karl Fischer titration has been widely used in quality and in-process control, research, manufacturing and development to determine the amount of water in various pharmaceutical raw materials and products samples. This rapid and accurate wet chemical analysis method can quantify water content in a variety of substances in concentrations from 10 ppm to 100%. BOC Sciences is able to perform Karl Fischer titration for accurate moisture measurements required by pharmacopoeias, ensuring the quality and stability of raw materials and finished products.

• Technology Principle

The Karl Fischer titration employs a double potential endpoint determination to quantify the titrant consumed by the water in the sample. During the titration, the titrant is added dropwise to the dissolved sample, and the titration is complete when enough titrant has been added to react with all analytes in the sample. An excess of titrant ions can be identified either through an indicator color change or change in the electric potential. This point at which the chemical reaction is completed is called the 'equivalence point' or 'endpoint'. Ultimately, the exact amount of analyte can be calculated from the volume of titrant consumed.

• Features
• Fast and selective determination of water content
• High precision and accuracy
• Suitable for most pharmaceutical sample types

Figure 2. Moisture measurements during the drying process. (Liu, X; et al. 2013)

Moisture Analyzer

Based on the principle of thermo-gravimetry (similar to 'Loss on Drying' (LoD) test), BOC Sciences also has introduced moisture analyzers to deliver fast, accurate and reliable measurements by optimizing processes and assisting with the faster release of batches of finished products.

• Our Workflow
• First, we weigh the sample in a moisture analyzer. Then, we heat the sample with an infrared radiator and continue track the weight
• When the sample stops losing weight, we stop heating and compare the new and initial weights to calculate the moisture determination of the sample
• Finally, our chemists analyze the final results to provide data to support your subsequent drug research and development projects and quality control monitoring

In-process Quality Control

Moisture content in raw materials such as Active Pharmaceutical Ingredients (APIs) and excipients is an important factor during blending and granulation in the production of drugs. Moisture content affects overall flow properties and the consistency of blended powders.

• Granulation

Granulation is an important step in the production of tablets and capsules. After wet granulation, the powder is dried. The residual moisture content needs to be measured at key points in this process.

• Tablets

As an important quality factor, the moisture content is measured prior to tablet pressing; if the mixture is too dry, the tablet will be unstable and if it is too wet, the tablet press may clog. Therefore, during tablet production, we carefully control the moisture content in the composite to ensure the overall shape, strength, solubility and shelf life of the tablets.

• Capsules

During the production of gelatin-based capsules, proper moisture maintains the strength and solubility of the capsule. We usually measure THE moisture in the raw gelatin powder and empty gelatin capsules.