Scientist of dodgy ethics taking millions in (7)
I believe the answer is:
chemist
'scientist' is the definition.
(chemist is a kind of scientist)
'dodgy ethics taking millions in' is the wordplay.
I cannot really understand how this works, but
'millions' could be 'm' (abbreviation) and 'm' is located in the answer.
an anagram of 'ethics' is 'cheist' which is within the left over letters.
No letters remain.
This explanation may well be incorrect...
'of' acts as a link.
(Other definitions for chemist that I've seen before include "Seller of medicines and toiletries" , "Drug store" , "Seller of medications" , "Nobel, say" , "Pharmacist, apothecary" .)