RU2315996C2 - Express-diagnosis method for detecting hyperoxyprolinuria cases - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: method involves taking daily urine sample and its analysis for Oxyprolin available in it. To do it, filtering paper is used for determining Oxyprolin content, one half of the paper being wetted with 7% cholramine B solution and the other one with solution containing 10 g of citric acid, 5 g of recrystallization-refined n-dimethylamine benzaldehyde and 10 ml HCl in 25 ml of water. The paper worked in this way is dried and its end wetted with chloramine B is introduced into daily urine sample. It is expected, when the paper becomes wet to the level wetted with n-dimethylamine benzaldehyde solution. Then the paper is withdrawn and dried in hot air jet. Brown spot arising, hyperoxyprolinuria is considered to be diagnosed, otherwise the diagnosis is considered not to be proved.

EFFECT: simplified test method; no prolonged sample pretreatment required.

Description

The invention relates to medicine, namely to laboratory diagnostics and is used to determine hyperoxyprolineuria in daily urine.

A known method for determining the concentration of oxyproline in biological material, based on the isolation and purification of oxyproline on a Dowex ion-exchange resin, followed by determination of the concentration with a 10% solution of p-dimethiaminobenzaldehyde in 96% ethanol (Application No. 4950767/14, KZ. Publ. 15.12.1994).

However, this method is time-consuming and requires preliminary preparation of the material using expensive sorbents, conducting a standard test, using spectrophotometric equipment.

The present invention is the development of a technically simple, affordable way to determine the concentration of oxyproline in the urine.

The problem is solved in that in the method of rapid diagnosis of hyperoxyprolineuria in daily urine, including taking a sample and its analysis for the content of oxyproline, use indicator paper, one part of which is moistened with a solution of chloramine B, and the other with a solution containing citric acid and purified p-dimethylaminobenzaldehyde while the appearance of a brown spot diagnoses the content of oxyproline in daily urine is higher than normal, and its absence - the content of oxyproline is within normal limits.

The method is as follows.

To determine the content of oxyproline in daily urine, indicator paper is used, which is a 3 × 30 mm piece of filter paper moistened with half a 7% solution of chloramine B, the other half with a solution containing 10 g of citric acid, 5 g of p-dimethylaminobenzaldehyde, 10 ml of HCl in 25 ml of water. P-dimethylaminobenzaldehyde is subjected to preliminary purification by recrystallization from 96% ethanol. The paper thus treated is thoroughly dried.

In patients staying at least a day on a collagen-free diet, daily urine is collected. Immerse the end of the indicator paper moistened with chloramine B in the urine and wait until the strip gets wet to the level moistened with a solution of p-dimethylaminobenzaldehyde. The strip is removed and carefully dried in a stream of hot air with a hairdryer. With excessive excretion of oxyproline in the urine, a brown spot appears on the indicator strip in the central part, while with normal excretion, the spot does not occur.

Clinical example

The content of free oxyproline, measured by the standard method, in the daily urine of patients B. and N. was 22.3 and 5.9 mmol / day, respectively. When lowering a strip of test paper processed in the above way, in the urine of patient B. after drying with a hairdryer, a brown spot appears in the central part of the strip, while when lowering a strip of test paper in the urine of patient N., a brown spot does not occur. Based on the data obtained, it was concluded that the content of oxyproline in the urine of patient B. is above normal, and in patient N. it does not exceed the upper limit of acceptable values.

The proposed method allows for a short time to diagnose hyperoxyprolineuria.

The proposed method is simple to execute, does not require expensive equipment, does not require preliminary sample preparation, and purified, highly sensitive p-dimethylaminobenzaldehyde is used as a reagent. This makes it possible to use the method at home in the expert diagnosis of conditions associated with impaired oxyproline excretion.

The method for the rapid diagnosis of hyperoxyprolineuria is used in the biochemistry laboratory of the Federal State Institution Scientific and Research Center "VTO" Academician G.A. Ilizarov.

Claims (1)

A method for the diagnosis of hyperoxyprolineuria, including sampling daily urine and its analysis for oxyproline content, characterized in that filter paper is used to determine the hydroxyproline content, one half of which is moistened with a 7% solution of chloramine B, the other half with a solution containing 10 g of citric acid, 5 g of purified p-dimethylaminobenzaldehyde recrystallized, 10 ml of HCl in 25 ml of water; the paper thus treated is dried and the end soaked in chloramine B is immersed in the collected daily urine; expect the paper to get wet to a level moistened with a solution of p-dimethylaminobenzaldehyde; after which the paper is removed and dried in a stream of hot air; by the appearance of a brown spot, the presence of hyperoxyprolineuria is diagnosed, by its absence - the absence of hyperoxyprolineuria.