Potent enough to target deep-set wrinkles, the L'Oréal Paris Revitalift Laser Pure Retinol Night Serum (£25) contains 0.2 percent retinol, but it's not really the amount that's important here. The brand created something it calls the Retinol Stabilisation Technology, which helps protect the retinol and keep it stable in the formula. Because of this new proprietary technology, the brand did not need to add anything to the retinol to protect it or use another derivative of vitamin A, meaning it's a pure form of retinol and not an ester like retinyl palmitate and retinyl propionate, for example. Additionally, the brand also added in hyaluronic acid, glycerin, and three different types of oils to further help stabilise the formula and keep skin happy and hydrated whilst the retinol gets to work.