| 摘要 |
A diagnostic composition for blood detection comprises a bibulous carrier impregnated with an organic hydroperoxide, as hereinafter defined, an indicator which changes colour in the presence of the hydroperoxide and blood, and a buffer maintaining the pH of the material under test at 4-7, wherein the hydroperoxide is encapsulated by means of a protein or polysaccharide encapsulating material hardened by a dialdehyde polysaccharide. The organic hydroperoxide is a hydroperoxide of cumene, diisopropylbenzene or paramenthane or is 2:5-dimethylhexane-2:5-dihydroperoxide; indicators specified are o-tolidine, o-toluidine, o-phenylenediamine, N:N1-dimethyl-p-phenylenediamine, N:N1-diethyl-p-phenylenediamine, benzidine, p-anisidine, dianisidine, o-, m- and p-cresols, a - and b -naphthols, catechol, guaiacol and pyrogallol; specified encapsulating materials are gelatin, algin, carrageenin, casein and albumin; and specified dialdehyde polysaccharides are dialdehyde derivatives of maize, wheat, tapioca or potato starch, cellulose, dextrans, algins or inulin, and the polysaccharides may be only partly oxidized to dialdehyde (e.g. with per-iodic acid). In examples, (1) an emulsion in water of acacia mucilage with dioctyl sodium sulphosuccinate and cumene hydroperoxide was first formed: a citrate buffer-gelatin mixture was added and this was followed by a dispersion of dialdehyde starch. A solution of sodium lauryl sulphate was added, the mixture homogenized and a further amount of citrate buffer was then added. The emulsion was impregnated into paper strips which were dried and thereafter had a solution of o-tolidine in chloroform applied thereto. The chloroform was evaporated to give the final product. (2) An emulsion in water of acacia mucilage with cumene hydroperoxide was formed and mixed with citrate buffer-gelatin mixture. Dialdehyde starch dispersion was added followed by sodium lauryl sulphate. The mixture was homogenized and a further amount of citrate buffer added. Test strips were prepared as in (1). Alternatives to acacia mucilage emulsifier are polyvinyl alcohol and gum arabic carboxyvinyl polymer. Alternative buffering materials may be based on tartrates, phosphates, phthalates or acetates. Specification 772,374 is referred to.
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