Photochemical tissue bonding using monomeric 4-amino-1,8-naphthalimides

Certain substituted naphthalimides have been shown to produce, on photochemical activation, mechanically viable bonds between a variety of tissue surfaces. It is believed that these compounds act as photochemically activated oxidants, catalyzing the formation of reactive intermediates in the extracellular matrices of approximated tissue surfaces. The condensation of these intermediates results in the formation of crosslinks between the intimate surfaces. Of particular interest is the application of this technique to the repair of tears in the typically unrepairable avascular zone of menisci. The menisci are collagen-rich fibrocartilaginous tissues that support up to 90% of the load across the knee joint and participate in important functions including shock absorption, joint stabilization, hyperextension prevention, and lubrication of the knee. Preliminary ex vivo and in vivo work in our laboratories has demonstrated that photochemically activated naphthalimides have significant potential for the repair of meniscal lesions. We describe preliminary ex vivo studies assessing the relative abilities of a variety of water-soluble monomeric 4-amino-1,8-naphthalimides to bond bovine knee meniscal tissue on visible light irradiation.