1 EXHIBIT 4.2 THIS WARRANT AND THE SECURITIES EVIDENCED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY OTHER SECURITIES LAWS, HAVE BEEN TAKEN FOR INVESTMENT, AND MAY NOT BE SOLD OR TRANSFERRED OR OFFERED FOR SALE...International Isotopes Inc • March 2nd, 2000 • In vitro & in vivo diagnostic substances • Texas
