Biomolecular recognition using submicron laser lithography

Direct beam biomolecular patterning on gold-coated glass substrates, using diffraction limited near infrared laser spot, is used for DNA recognition and specific ligand-receptor interactions. Using a microscope objective lens, a near infrared laser beam is focused onto a glass slide coated with 50-Angstrom gold film. Localized laser absorption results in partial melting and ablation of gold. Spatially moving the laser spot, a stable etched gold pattern is obtained at submicron resolution. During the process, submicron particles in suspension aggregate along the melted gold film. The submicron particles are themselves coated with specific biomolecules, like the protein avidin or single stranded DNA oligomers, for specific biomolecular recognition. This opens many possibilities for biomolecular networks, biochip microfabrication, and bioelectronic circuitry. (C) 1998 American Institute of Physics.