The present invention provides a water-based ink composition in which the wettability, surface tension, antibacterial properties, and other properties are controlled based on a simple formulation. The water-based ink composition of the present invention contains a semi-polar boron compound. Semi-polar boron compounds represented by diglycerin borate exhibit superior wettability in an ordinary environment, and addition of such a compound achieves a water-based ink composition well-balanced in surface tension, wettability, and drying property even if the composition is prepared according to a simple formulation. The optimum quantitative range for addition of the semi-polar boron compound depends on whether the coloring material contained in the watercolor ink composition is a dyestuff or a pigment. When the coloring material is a dyestuff, the quantitative range is preferably 0.5 to 3.0% by weight relative to the entire quantity of the water-based ink composition. When the coloring material is a pigment, the quantitative range is preferably 0.05 to 10% by weight relative to the same.

Methods and compositions for detecting and measuring the concentration in solution of polyhydroxyl compounds, such as sugars. The invention makes use of certain dye compositions that, when linked to a derivative of boronic acid (or boronate ion), arsenious acid (or arsenite ion), or germanic acid (or germanate ion), exhibit quantitative responses to the presence of polyhydroxyl species.

An aqueous ink composition includes a dye component which contains a water-soluble xanthene dye or a water-soluble phthalocyanine dye, each of which includes a moiety of formula (I) when the water-soluble dye is in the form of a free acid, ##STR1## a surfactant. By use of this aqueous ink composition, a method of forming images on an image receiving medium is performed which includes the step of ejecting the aqueous ink composition in the form of droplets by the application of thermal or mechanical energy thereto onto an image receiving medium with a Stockigt size degree of 3 seconds or more as defined in the Japanese Industrial Standards P-8122.

A printing system including a boronic acid dye and a coated print medium. The boronic acid dye comprises a boric acid group or a boronic acid group attached to the dye. The boronic acid dye covalently binds to a polyhydroxylated material present in a coating layer of the print medium, fixing the boronic acid dye to the print medium. A method of reducing dye migration on a print medium is also disclosed.

Methods are provided for the determination of the concentration of biological levels of polyhydroxylated compounds, particularly glucose. The methods utilize an amplification system that is an analyte transducer immobilized in a polymeric matrix, where the system is implantable and biocompatible. Upon interrogation by an optical system, the amplification system produces a signal capable of detection external to the skin of the patient. Quantitation of the analyte of interest is achieved by measurement of the emitted signal.