Abstract: A metered liquid sample collection device includes an absorbent pad, a color indicator concealed from view when the absorbent pad is dry, a mechanism for revealing the color indicator when the appropriate volume of a sample has been collected, and a handle for manipulating the metered liquid sample collection device. The metered liquid sample collection device employs a hydrophilic channel separating the absorbent pad from the color indicator and indicator zone. The mechanism can be a concealed insoluble colored spot deposited on a back face of the indicator zone that only becomes visible when the indicator zone becomes wet, a hydrochromic dye that changes color upon interacting with water, a soluble dye that dissolves into the sample and moves with the sample as it wicks up a zone adjacent the indicator, or an electrical circuit that is completed when the indicator zone becomes wet.

Abstract: An assay device including a loading zone for a sample that may contain an analyte, an activator in communication with the loading zone from which at least one activator is displaced by presence of the analyte, an amplifier in an inactive state in communication with the activator that becomes activated in the presence of the activator, a biomatrix barrier in communication with the activated amplifier that is degraded or modified by the activated amplifier, and an indicator responsive to the degradation or modification of the biomatrix barrier, which in turn reflects a concentration of the analyte in the sample loaded on the device. The selection of analyte or displacement of the activator by presence of the analyte may occur off-platform and/or may rely on use of non-covalent interactions. The activator may include an enzyme or other reagent that activates the amplifier. Also, associated methods.

Abstract: Paper supports for fluid or cells having a decreased surface area are provided. Methods of producing such support comprise contacting the support with a composition comprising sodium periodate such that the surface area is decreased. The support or a portion thereof are reduced in surface area and the reduced portion or reduced entire support is degradable. The resulting paper support may also have hydrophilic channels and/or hydrophobic barriers that are also reduced in surface area. In embodiments the support may be a micropad or support for producing a tissue have desired structure. The support is miniaturized dialdehyde paper support that is malleable and retains its structure.

Abstract: An assay device including a loading zone for a sample that may contain an analyte, an activator in communication with the loading zone from which at least one activator is displaced by presence of the analyte, an amplifier in an inactive state in communication with the activator that becomes activated in the presence of the activator, a biomatrix barrier in communication with the activated amplifier that is degraded or modified by the activated amplifier, and an indicator responsive to the degradation or modification of the biomatrix barrier, which in turn reflects a concentration of the analyte in the sample loaded on the device. The selection of analyte or displacement of the activator by presence of the analyte may occur off-platform and/or may rely on use of non-covalent interactions. The activator may include an enzyme or other reagent that activates the amplifier. Also, associated methods.