Abstract: An optical biosensor has a first enclosure with a pathogen recognition surface, including a planar optical waveguide and grating located in the first enclosure. An aperture is in the first enclosure for insertion of sample to be investigated to a position in close proximity to the pathogen recognition surface. A laser in the first enclosure includes means for aligning and means for modulating the laser, the laser having its light output directed toward said grating. Detection means are located in the first enclosure and in optical communication with the pathogen recognition surface for detecting pathogens after interrogation by the laser light and outputting the detection. Electronic means is located in the first enclosure and receives the detection for processing the detection and outputting information on the detection, and an electrical power supply is located in the first enclosure for supplying power to the laser, the detection means and the electronic means.

Abstract: A formulation of markers for the identification of liquids is provided. Formulation includes a marker which has a high molar absorptivity in the wavelength range of 600-1000 nm. The invention further provides for a combination marker including a marker with known absorbtivity within a wavelength range and a molecular marker including various molecular formulations and isotopic markers used in conjunction. The invention further provides a method of testing for a marked liquid which employs the testing for an absorbance marker as a screening mechanism to reduce the number of tests for the molecular marker required to assure the unadulterated nature of the liquid.

Abstract: A process for marking an article in a manner which is optically invisible and difficult to detect. The process is carried out by selecting a laser luminophore which fluoresces in a predetermined portion of the spectrum when exposed to an excitation light of predetermined wavelength and applying the laser luminophore to the article in an amount which is optically invisible when the article is exposed to electromagnetic radiation but which is sufficient for machine detection when the article is exposed to an excitation light of predetermined wavelength.