Perhaps lead with a small amount (7)
I believe the answer is:
element
I believe this is a double definition.
'perhaps lead' is the first definition.
(I know that lead is a superconducting element)
'small amount' is the second definition.
(I've seen this before)
'with a' acts as a link.
(Other definitions for element that I've seen before include "Constituent part (7)" , "Primary chemical substance" , "Singular ingredient" , "silver perhaps?" , "Basic substance or feature" .)