A system and method are presented for use in monitoring brain activity of a subject. The devices and applications may be used in connection with items that are associated with an RFID tag, and optionally a magnetic security element. The invention includes a flexible element composed of one or more bio-compatible polymers, where the element is breathable, and allows contact between the mother and the infant. In particular, the method allows rapid isolation of high expression recombinant antibody-producing cell lines, or may be applied directly to rapid isolation of specific hybridomas, or to the isolation of antibody-producing transgenic animals.