초록 ▼

Chemical analysis of a sample with reagents spotted on a fibrous or porous medium employs a medium pretreated both with reagents and with conditioning agent. The conditioning agent increases the degree to which the liquid reactants wet the medium. One form of pretreated medium has different reagents

Chemical analysis of a sample with reagents spotted on a fibrous or porous medium employs a medium pretreated both with reagents and with conditioning agent. The conditioning agent increases the degree to which the liquid reactants wet the medium. One form of pretreated medium has different reagents located predominantly within different selected zones. Liquid is applied to the medium, typically as diluted sample, at a rate selected to enhance formation of repeatable spots. In one embodiment the liquid is applied by flowing it onto a wick element seated on the medium. The wick is disc-like and small relative to the spot which the reactants form on the medium. The disc can be pretreated to carry reagent, which the liquid transfers to the medium. The analysis instrument receives a reaction medium between selectively recessed upper and lower surfaces aligned in opposition at the reaction spot being analyzed. The analysis can, depending on the analytical reaction, the medium and the precision required, proceed while the reactants are wet or can measure a reaction product after the reactants are dry. A single point analysis can also be made.

대표청구항 ▼

A method for preparing a porous medium for use in chemical spot test analysis employing a measured parameter responsive to concentration of a reaction-produced material at a test site on the porous medium, said method including the improvement comprising the step of exposing at least said test site

A method for preparing a porous medium for use in chemical spot test analysis employing a measured parameter responsive to concentration of a reaction-produced material at a test site on the porous medium, said method including the improvement comprising the step of exposing at least said test site of said medium to a liquid preparation conditioning agent having a balance of hydrophobic and hydrophilic properties for retarding the spreading of liquid in the medium and for increasing the concentration of liquid the medium can hold, said exposure being sufficient, after drying, to diminish the absorption of liquid by the porous structure of said medium.