What is use of LOQand LOD in residual solvent method validation. Suppose methanol limit 3000 ppm and calculated result in test sample 2500 then sample is pass then why in residual solvent LOQ and LOD performed.
In analytical method validation the purpose of establishing LOQ and LOD is to determine how sensitive analytical method is to detect the analyte compound. The more sensitive analytical method will reflect in accurate results. The threshold limit of LOQ & LOD should be in compliance with the regulatory requirements of Analytical method validation. Generally, the traces of solvents much below the higher limit in a product should be detectable and quantifed by having a senstive analytical method. If the analytical method is not sensitive then it can not detect the traces of solvents quantitatively, in such cases the results will be reported as below LOQ. Moreover, it is a regulatory requirement to establish LOD & LOQ of analytical methods (instrumental) as a part of Analytical method validation.