An extraction system for testing microbial contamination includes a biocompatible outer vessel that has a side wall and a biocompatible suspension system that is positionable within an interior of the biocompatible outer vessel. The biocompatible suspension system includes a horizontal member on which a sample may be supported and a securement mechanism that is engagable with the side wall of the biocompatible outer vessel to maintain the suspension system at a desired position within the biocompatible outer vessel.

The present invention relates to a biosensor for determining an analyte comprising a substrate, a working electrode comprising an electrically conductive pad in conductive contact with a mediator layer, and an enzyme layer in diffusion-enabling contact with said mediator layer, wherein said mediator layer is an electrodeposited mediator layer, and wherein said mediator layer comprises, in an embodiment consists of, an electrocatalytic agent. The present invention further relates to a method for manufacturing a biosensor, comprising providing a substrate having at least one conductive pad, electrodepositing a mediator layer onto at least part of said conductive pad, wherein said mediator layer comprises, in an embodiment consists of, an electrocatalytic agent, and depositing an enzyme layer onto at least part of said mediator layer. Moreover, the present invention relates to uses and methods related to the biosensor of the present invention.

A mutant cytochrome protein originated from a cytochrome protein having three heme-binding domains, which mutant cytochrome protein lacks the first heme-binding domain and the second heme-binding domain as counted from the N-terminus, is provided. The mutant cytochrome protein may lack a region(s) containing the first and second heme-binding domains.

NADP-dependent oxidoreductase compositions, and electrodes, sensors and systems that include the same. Analyte sensors include an electrode having a sensing layer disposed thereon, the sensing layer comprising a polymer and an enzyme composition distributed therein. The enzyme composition includes nicotinamide adenine dinucleotide phosphate (NAD(P).sup.+) or derivative thereof; an NAD(P).sup.+-dependent dehydrogenase; an NAD(P)H oxidoreductase; and an electron transfer agent comprising a transition metal complex.

Provided are an amadoriase that is less likely to be influenced by oxygen concentration and a method and a reagent kit for measurement of HbA1c using such amadoriase. Provided are an amadoriase that is obtained via substitution of one or more amino acid residues at a position or positions corresponding to the position(s) selected from the group consisting of positions 280, 267, 269, 54, and 241 of the amadoriase derived from the genus Coniochaeta, a method for measurement of HbA1c, a reagent kit for measurement, and a sensor using such amadoriase. The modified amadoriase according to the invention has a lowered oxidase activity and an enhanced dehydrogenase activity, and this enables the use of an electron mediator, and this reduces the influence of oxygen concentration. Thus, HbA1c can be measured with high sensitivity.

A method for detecting an analyte is described in which the simultaneously binding of two fusion proteins (i.e., a sandwich assay in solution) is used, bringing two halves of a split enzyme together to produce product, which is detected via a FRET-based biosensor. The method may incorporate an autocatalytic feedback loop that responds to enzymatic product by producing more product to provide ultrasensitive, bistable detection of analyte that is tunable over several orders of magnitude. This system is broadly applicable for protein and small molecule detection.

NADP-dependent oxidoreductase compositions, and electrodes, sensors and systems that include the same. Analyte sensors include an electrode having a sensing layer disposed thereon, the sensing layer comprising a polymer and an enzyme composition distributed therein. The enzyme composition includes nicotinamide adenine dinucleotide phosphate (NAD(P).sup.+) or derivative thereof; an NAD(P).sup.+-dependent dehydrogenase; an NAD(P)H oxidoreductase; and an electron transfer agent comprising a transition metal complex.

A system for preparing a sample containing hemoglobin HbA1c for measurement by an electrochemical sensor includes a lysing formulary, the lysing formulary including a zwitterionic surfactant. The system further includes a oxidizing formulary, the oxidizing formulary including a cationic surfactant and a isothiazoline derivative and a protease formulary, the protease formulary including a molecule including an azole.

The invention provides amperometric analyte sensor systems comprising one or more electrodes designed to monitor in vivo levels of 3-hydroxybutyrate (and optionally glucose as well) in order to facilitate the management of diabetic ketoacidosis. The invention further includes compositions, elements and methods useful with such amperometric analyte sensor systems.

A coated electrode includes an electrode, a coating configured to immobilize biomolecules, and a coating configured to improve electron transfer rate. Methods of making the coated electrode are also provided. A biosensor comprises a plurality of electrodes, each electrode including the coated electrode.