We have completed clinical trials proving that SPOTMYUV™ changes colour at the correct time (when your SPF 50 sunscreen is only giving you SPF 10), and that the top layer (skin-mimicking material) loses sunscreen at the same rate as skin.
We use the same techniques that the world’s leading academics use for measuring sunscreen on skin, which are detailed at a high-level in our reports. In short, we use alcohol swabs to measure the sunscreen on skin, and quantify using UV/Vis spectroscopy.
We compare
- The amount of sunscreen taken off of the alcohol swab
- The amount of sunscreen on a SPOT (right beside the swabbed area of skin)
- The colour of the SPOT in sunlight
We check to see that (1) and (2) have an equivalent amount of sunscreen. We also then check if that amount of sunscreen is above or below 0.8mg/cm^2, and compare that to the colour of the SPOT in sunlight (3). The test is a pass if (1)=(2), and if the colour of (3) reports the correct colour for the surface coverage (purple if <0.8mg/cm^2, otherwise clear)
When we do this over time, we can track how sunscreen comes off both skin and SPOT.
We show that when SPOT turns purple, it means that there is an effective SPF of 10 on SPOT, and thus on skin, so the user should reapply sunscreen soon.