Laboratory glass ware cleaning validation

Dear all
Please suggest the best and unanimously accepted cleaning validation practices for laboratory glass ware. Can we use the TOC for that if yes how we will proof the inorganic contents in glass ware what will be our motto.
If our motto is to check the used detergent how we will ensured that what ever the reading we are finding by TOC, is correspond to the respective used detergent.
Please suggest
R C Pantola

Dear R.C. Pantola,

I don´t think there is the ideal one-fits-all cleaning validation practice. If you target the elimination of detergent in your lab glassware, first you need to know the exact formulation of the detergent, and only then you can develop a suitable analytical method. TOC is an excellent way to detect traces, but being completely nonspecific the whole organic carbon found has to be assigned to your target analyte, and the inorganic compounds of the detergent, as you say, won´t be detected. Probably the simplest way would be a combination of TOC and measurement of sodium (by atomic absorption spectrophotometry), and a sound recovery test to correlate the values found with actual detergent residues.

The question is why it is so critical to validate the detergent elimination from the lab glassware. Without knowing the background of the issue, usually the lab glassware cleaning is not a regulatory requirement and does not require a validation. If the detergent is an interference in the analytical method, perhaps there is no need for a validation but a thorough cleaning (even with the old-fashioned sulphochromic mixture) may be enough.

Best regards