Hi Carly,
Topical collagen based products won't work as collagen is a big molecule and there is no way it could pass through the skins layers to do any good for dark eye circles. You will just be applying them and them washing them away. Only way to boost collagen is internally i'e radiofrequency, LED light therapy, injections and maybe collagen drinks (i'm still not convinced on the drinks though).
Firstly you should check the dark eye circles are not due to an underlying health problem like anemia etc.
Secondly i would use a galvanic device to remove any dirt impurities etc then use LED Light therapy and/or Radiofrequency to internally boost collagen and bring blood circulation to the eye area. this increase in blood flow will bring with it nutrients and proteins to heal, repair and revive the eye area. I've also heard people using microneedling to help with dark circles but i've not tried it - the thought of needles on my under eyes scares me a little!
Thirdly i would use a good Ferulic acid or vitamin C based eye gel/serum - this will help to brighten the area and prevent signs of ageing
Be careful with some eye skincare, they say brightening but when you look at it under a magnifier the cream will have glitter like particles which when on the skin reflects light particles and makes it appear lighter but its not actually solving the problem! - i was caught out my this once and i wasn't very happy!
Hope this helps and If you need any further help with this just give me a shout!
Best wishes,
Mel