“Here’s the smell of the blood still: all the perfumes of Arabia will not sweeten this little hand.”
olfactory imagery(sense of smell= suggest her guilt- blood-motif- the guilt hasn't just stained her physically but has fully engulfed her to the point where her senses are affected-inescapable sensory experience
no luxury or power can cover up her moral corruption.
"little hand"- trying to feminise herself again- realisation has hit she no longer wants to be masculine any more- Shakespeare showing that attempts to subvert ones gender role will eventually lead to regret- also shows how because she is a woman- she is weak and is incapable of dealing with violence
her guilt is manifested both physically and psychologically-Shakes crafts her downfall as a moral justice