Within the framework of cleaning validation, the riboflavin test is discussed time and again. This test is meant to show the equipment cleanability in advance. The individual performance of the test made it well-nigh impossible to make comparisons and gave repeatedly rise to questions. In December 2007, the VDMA (German Process Plant and Equipment Association), with 3,000 mainly medium-sized member firms from the capital goods industry one of the largest and most important industry associations in Europe, published an information sheet on this test. "Riboflavin test for low-germ or sterile process technologies Fluorescence test for examination of cleanability For food, aseptic, pharmacy and chemistry." On 10 pages, the information sheet gives advice on agreement, planning, performance and documentation of a fluorescence test. The following chapters are of special interest:
Apart from these, there is an introduction (Chapter 1), the definition of the scope (Chapter 2) as well as explanations of terms and definitions (chapter 3). Another very important part is chapter 8 (Annex), in which ingredients and recipes of test solutions as well as a schematic sketch of an installation for carrying out a fluorescence test are defined and specified.
Conclusion: The document can be helpful for the pharmaceutical industry since the information sheet describes a standardised procedure of the riboflavin test. Concentrations and the optional use of a thickening agent are defined. An alternative to riboflavin as a fluorescent substance is also indicated (uranin). Interestingly, the text recommends that drying of the fluorescent dye should be avoided. This might need to be discussed, since some riboflavin tests deliberately opt for the drying as the worst-case scenario. The information sheet can be downloaded from the VDMA website.
On behalf of the European Compliance Academy (ECA)
PS. Within the framework of the ECA event Cleaning Validation in Prague on 15-16 April 2010, we will also deal with the riboflavin test. Details on the event can be found here.