Abstract: A test agent includes a composite probe having at least one nanoparticle having multiple metal atoms, a directing agent, and an enzyme. The directing agent attaches the probe to a target in a test sample. The test sample and bound probe are then treated with an enzyme substrate. A method of detecting a target in a test sample includes exposing the test sample to the probe, then treating the test sample with an enhancement or development solution to deposit at least one of a fluorophore, a chromogen, or a metal.

Abstract: Disclosed embodiments concern site-specific, enzymatic-directed deposition of elemental metal for in-situ analysis. Enzyme substrates are contacted with metal ions and subsequently direct the deposition of elemental metals. Sensitive and selective detection of target molecules, such as biomarkers in various biological samples, can be obtained using various methods, such as in-situ chromogenic immunohistochemical (IHC) detection with bright field light microscopy.

Abstract: A test agent includes a composite probe having at least one nanoparticle having multiple metal atoms, a directing agent, and an enzyme. The directing agent attaches the probe to a target in a test sample. The test sample and bound probe are then treated with an enzyme substrate. A method of detecting a target in a test sample includes exposing the test sample to the probe, then treating the test sample with an enhancement or development solution to deposit at least one of a fluorophore, a chromogen, or a metal.

Abstract: Novel metal-lipid molecules have the formula M-Or-L. M represents a cluster or colloid of atoms of Au, Ag, Pt, Pd, or combinations thereof. Or is an organic group covalently attached to the metal atoms. L represents a lipid moiety. In a preferred embodiment, M represents a cluster of about 50-70 gold atoms having a diameter of about 1.4 nm in diameter and L represents dipalmitoyl phosphatidyl ethanolamine.

Abstract: Small organometallic probes are disclosed which include a core of metal atoms bonded to organic moieties. The metal atoms are gold, silver, platinum, palladium, or combinations thereof. In one embodiment, a multifunctional organometallic probe is disclosed which includes a core of metal atoms surrounded by a shell of organic moieties covalently attached to the metal atoms, a fluorescent molecule, e.g., fluorescein, covalently attached to one of the organic moieties, and a targeting molecule, e.g., an antibody, covalently attached to another of the organic moieties. In another embodiment, a small metal cluster of palladium or platinum is disclosed in which the central metal core comprises platinum or palladium in which the central metal core is from about 1.8 to 3.6 nm in diameter and contains about 309 to about 2,057 metal atoms. This metal core has 1,10-phenanthroline organic moieties covalently attached to the metal core. A process for making this palladium and platinum cluster compound is also disclosed.

Abstract: Small organometallic probes comprise a core of metal atoms bonded to organic moieties. The metal atoms are gold, silver, platinum, palladium, or combinations thereof. In one embodiment, a multifunctional organometallic probe comprises a core of metal atoms surrounded by a shell of organic moieties covalently attached to the metal atoms, a fluorescent molecule, e.g., fluorescein, covalently attached to one of the organic moieties, and a targeting molecule, e.g., an antibody, covalently attached to another of the organic moieties.