Most people are confused to understand the difference between moisture content and Loss on drying (LOD). So to know it read the entire section in this post. First, read a little bit about moisture analyzers. A moisture analyzer is used to determine water content in the sample. So questions are how many types of moisture analyzers are used in pharma to determine Loss on drying or LOD and the Principle of moisture analyzer.
Types of Moisture analyzers
- IR moisture analyzer
- Halogen Moisture analyzer
IR analyzer: IR Moisture analyzer is the equipment used to determine the moisture content of sample with a loss on drying method. It consists of a weighing unit for sample weight and a heating unit (IR) to heat the sample.
Halogen analyzer: it emits Infra-Red radiation and radiates moisture that is present in the sample.
What is moisture content:
Moisture content is the amount of water present in the sample
Formula for moisture content:
Principle of Moisture analyzer:
The principle of moisture analyzer works on the thermos gravimetric is also referred to as the “loss on drying” principle.
Loss on Drying (LOD) test:
The loss on drying test is designed to measure the amount of water and volatile solution, expressed as w/w present in the sample when the sample is drying under a certain condition.
The formula for % LOD check:
Difference between moisture content and (LOD)
The Karl Fischer titration method is used to determine moisture content, and the result only contains water; for example, the result does not contain any other volatile content.
Heat the sample below its melting point in an oven at a specific condition (105° for 3 hrs) to measure the drying loss, including all volatile materials, including water content and solvent.