A method of bioactive molecule delivery includes providing a first aqueous medium comprising native graphene oxide and a second aqueous medium comprising a bioactive molecular component that includes Gd(III)-labeled molecules; mixing said first and second media to form a mixture thereof; co-incubating the mixture for a first period of time for coupling said molecular component on a surface of said native graphene oxide, to provide a co-incubation product; and contacting a cellular medium with said co-incubation product for a second period of time for cellular delivery of said bioactive molecular component.