On the protection of insulin against UV-Light
With different wordings, all insulin producers advise users of insulin pens to put the pen cap on the pen after each use to protect the insulin from light.
The reason is that especially sunlight (with UV-radiation) gradually will damage the insulin. The damaging effect begins immediately when the insulin is exposed to the light.
For details see the article Correia M, Neves-Petersen MT, Jeppesen PB, Gregersen S, Petersen SB (2012) UV-Light Exposure of Insulin: Pharmaceutical Implications upon Covalent insulin Dityrosine Dimerization and Disulphide Bond Photolysis. Plos ONE, 7(12): e50733, doc 10.1371/journal pone 0050733
The article describes how continuous exposure of insulin to UV-Light with wavelengths and strengths similar to the total irradiance of sunlight in the UVB region will damage the insulin.
The effect of insulin exposed to such light for 1,5 hours is reduced by 61,7 %.
Furthermore, the article notes that commercially available indoor light sources such as fluorescent tubes, quartz halogen lamps and even tungsten filament incandescent lamps can provide damaging UV-Light.
It is therefore recommended putting the cap on the insulin pen after each use and in any case not use the insulin pen outdoor in direct sunlight.
The use of DUKADA Trio does not change these recommendations!
However, we have tested that the plastic of the DUKADA Caps protects against penetration of UVB-Light (as do the original caps). The difference is that the original caps are totally removed from the insulin pens during injections. To the contrary, when using the DUKADA Trio Cap, the main part of the cap stays on the pen during injections.
Although there are so-called control windows on the main part of the DUKADA Trio Cap, the Cap covers between 75% and 96% of the insulin in the container during injections (depending on how much insulin is remaining in the container).
It is, therefore, safe to conclude that the usage of the DUKADA Trio Cap gives better protection against light during injections than the usage of the original caps.