Artist adopted by fashion designer in Spain in state of isolation (10)
I believe the answer is:
quarantine
'state of isolation' is the definition.
(I've seen this before)
'artist adopted by fashion designer in spain' is the wordplay.
'artist' becomes 'RA' (Royal Academician, member of Royal Academy of Arts).
'adopted by' is an insertion indicator (I've seen this in other clues).
'fashion designer' becomes 'quant' (I've seen this before).
'spain' becomes 'e' (abbreviation for Espana).
'ra' put within 'quant' is 'quarant'.
'quarant'+'in'+'e'='QUARANTINE'
'in' is the link.
(Other definitions for quarantine that I've seen before include "Precautionary seclusion" , "Period of enforced isolation" , "Period of isolation to prevent spread of disease" , "State of isolation" , "solitary confinement" .)