The Messenger of Allah ﷺ never touched a woman with his hand. He would only take her pledge verbally, and once she had given it, he would say, "Go, for I have accepted your pledge."
أخبرت عن بيعة النساء:
ما مس رسول الله ﷺ بيده امرأة قط، إلا يأخذ عليها، فإذا أخذ عليها فأعطته قال: اذهبي فقد بايعتك