Abstract: The present invention is directed to a method and apparatus for an immunoassay technique that uses amperometric measurements to rapidly analyze different pathogenic microorganisms, including bacteria, viruses, toxins, and parasites. In accordance with one aspect of the present invention, at least one conductive membrane is used to provide support for antibody immobilization and serve as a working electrode; it could also be independent rather than the working electrode. This conductive membrane or powder can be fabricated of a conductive material or can be a nonconductive material over which a conductive material is coated. In either case, the proposed technique is adaptable for use with different materials so as to form a membrane having a pore size that is suited to the particular application. Another aspect of the present invention relates to a compact and simple disposable element that can be easily disposed of after use.

Abstract: The present invention is a disposable element for assaying food samples and a method for using the element. The disposable element includes a container having first, second, and third ports, a prefilter disposed in the container, an immuno-sorbent layer having antibodies to a target microbe affixed thereto, the immuno-sorbent layer also being disposed in the container, and an electrode in contact with the immuno-sorbent layer. The prefilter and immuno-sorbent layers are positioned in the container such that a sample introduced into the first port passes through the prefilter and the immuno-sorbent layer when a pressure differential is created between the first and third ports. In addition, liquid entering the second port passes through the immuno-sorbent layer, but not the prefilter, when a pressure differential is created between the second and third ports. The prefilter preferably has a pore size between 10 and 30 microns.

Abstract: A reusable, miniature, implantable electrochemical sensor, a method of making the same, and a powder therefor are provided. Enzyme material is immobilized on bulk particulate matter, and a reaction chamber of the sensor is then filled therewith. The sensor is implanted in an environment where it comes into contact with a specific component of a fluid with which the enzyme material chemically reacts to produce electrical signals for measuring the reaction. The method preferred for preparing the powder which is used in the electrochemical sensor involves first covalently bonding a quantity of an enzyme to fine particles in powder form to immobilize the enzyme is cross-linked to a non-enzyme protein with a cross-linking agent. Finally, the particles are added containing the immobilized enzyme cross-linked to a protein from the first step to the enzyme cross-linked to a protein from the second step to obtain the powder.

Abstract: A reusable, miniature, implantable electrochemical sensor, a method of making the same, and a powder therefor are provided. Enzyme material is immobilized on bulk particulate matter, and a reaction chamber of the sensor is then filled therewith. The sensor is implanted in an environment where it comes into contact with a specific component of a fluid with which the enzyme material chemically reacts to produce electrical signals for measuring the reaction.

Abstract: An arrangement for prolonging the useful life of an electrochemical refillable implantable glucose sensor employing an enzyme material such as glucose oxidase immobilized on bulk particulate matter suspended in a fluid for reaction with components of bodily fluids and which enzyme material when exhausted or degraded after reaction may be replaced by fresh enzyme-loaded particles.

Abstract: An improved membrane electrode for measuring the concentration of a non-ionic species in an essentially aqueous medium comprising:an electrically conductive substrate;a first coating surrounding said substrate composed of a mixture of polymeric material, an anion exchange material, and a water-insoluble alkaline earth metal salt of said non-ionic species, anda hydrogel coating of material surrounding said first coating having a positive charge of sufficient potential to prevent leaching of the substantial amounts of the alkaline eath metal component of said salt.

Abstract: A surgically implantable areola and nipple prosthesis comprising a base and a nipple forming protrusion, wherein said base is concave on one surface, and convex on the other surface and wherein the nipple forming protrusion is integrally formed onto the convex surface, and wherein the concave surface of the implantable nipple prosthesis may be affixed to a usual breast implantable sac in a location and manner so that the nipple forming prosthesis is oriented in as nearly normal position as possible, or wherein the invention may be implanted in a pocket in tissue as a separate item; and wherein the skin and tissue of the patient is closed about the areola and nipple forming prosthesis, and wherein the patient's skin will naturally assume the shape of the areola and nipple forming prosthesis, and wherein the exterior skin now shaped as an areola and nipple can be colored to resemble an areola and nipple, and wherein the coloring may be of the removable type, such as make-up, or of the more permanent type, such

Abstract: An aqueous gel comprising water and a cross-linked polyacrylamide provides a transparent, thermally insulating cover for a solar pond. Heat losses from the top of the pond to the atmosphere due to convection currents are minimized as well as losses due to evaporation. Advantage is taken of convection currents to maximize heat extraction efficiency.