SU1283251A2 - Method of indicating contamination of environment objects with chemical substances - Google Patents

Abstract

The invention relates to a method for indicating the pollution of environmental objects by chemicals, can be used in the field of industrial and sanitary hygiene, and is an improvement of the known method according to the author. No. 1010128. The purpose of the invention is to increase accuracy. soil dosing, which is achieved by preliminary mixing the test culture of microorganisms with a 5% aqueous solution of polyvinyl alcohol in a mass ratio of the suspension of microorganisms and a solution of polyvinyl alcohol 1: (0.004-0.01), respectively. Improving the accuracy of the indication is provided by increasing the viscosity of the liquid in which the microorganisms are suspended, which makes it possible to layer the analyzed sample on the test culture without mechanical mixing and to stabilize the concentration gradient of the displayed sample. 3 tab., 1 Il. (L

Description

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The invention relates to environmental protection, in particular to the field of industrial and sanitary hygiene, and is additional to the basic author. St. No. 1010128.

There is a known method of indicating the contamination of environmental objects with chemical substances by exposing a sample to a test culture of microorganisms with subsequent monitoring of the change in the culture, which consists in introducing a sample at one end of a stretched cuvette containing a suspension of microorganisms, showing a chemotaxis effect on displayable substances , measuring the redistribution of the concentration of microorganisms along the cuvette and the difference in the concentration of microorganisms along the cuvette in controlled areas — determining the degree of contamination zneeni. The redistribution of microorganisms on the planet is measured by photometric method,

The purpose of the invention is to improve the accuracy of indication of contamination.

The essence of the invention is that the suspension of the test-culture of microorganisms is pre-mixed with a 5% aqueous solution of polyvinyl alcohol in the mass ratio of the suspension of microorganisms and the solution of polyvinyl alcohol 1: (0.004-0.01), respectively. This increases the viscosity of the fluid in which the microorganisms are weighed, which makes it possible to layer the analyzed sample on the test culture without mechanical mixing and to stabilize the concentration gradient of the indicated sample,

The drawing shows an installation diagram for implementing the method.

The installation contains a radiation source 1, flexible fibers 2, two cuveys 3 and 4, in the thin zones of which the test culture 5 is contained, weighed in lmDkost, indifferent to microorganisms, mixed with a 5% aqueous solution of polyvinyl alcohol. The cuvette 3 (experimental) in the upper zone contains the displayed sample 6, the cuvette 4 (control) - the control sample 7, the controlled zones 8 are in the cuvettes. The scheme contains the photodetectors 9 and the measuring device 10,

A suspension of a test culture of 5 microorganisms (MO) (Fig. 1) of a known concentration with a pronounced chemotaxis to the displayed substance is mixed with an aqueous solution of polyvinyl alcohol (PVA) at a mass ratio of test culture 5 and a solution of polyvinyl alcohol 1: (0.004-0.010 Test -culture 5 is introduced into the control and experimental cuvettes 4 and 3. Above the test culture 3, the sample 6 is layered in the cuvette 3 (tested for the contaminant), the control sample 7, the PVA test in the MO 5 test culture allows em sample layered on the test culture MO without mixing, i.e., in the cuvettes, there are two liquid isolated layers, the lower one being the test culture MO, the upper one being the sample. The boundary between the two layers of liquids due to their different viscosity remains stable throughout the measurement and, as shown by the experimental verification, within a few hours. At the same time, this border does not prevent the test culture cells from migrating in their preferred direction: MO cells move to the upper cell area, if the drum does not contain a toxicant, in the presence of a toxicant, the MO cell concentration in erhney controlled area will be smaller than the toxicant more.

The redistribution of MO cells in the cuvettes under the action of a toxicant (chemo-toxic reaction) is measured photometrically at the facility (Fig. 1). The light fluxes from the source 1 through the optical fibers 2 are supplied to the monitored zones 8 in the upper zones of the cuvette 3 and 4. The radiation from the cuvette through another pair of optical fibers 2 is fed to the photodetectors 9. The signals of the photodetectors are measured by the device 10. control (I) and experimental (ijji) ditch. The difference d1 is greater, the more toxicant in the sample.

Introduction to the suspension of the test culture of the PVA solution in the indicated ratios does not cause cell death, does not reduce their mobility, and does not affect growth and reproduction for several days. At the same time, the introduction of the PVA solution allows stabilizing the toxicant concentration gradient in the cell with the MO test culture, which makes it possible to reduce the spread of data, thus reducing the relative indication error from 46% by a known method to 16% by the proposed method.

Tables 1 and 2 give comparative data on the accuracy of copper sulfate indication of the proposed and known methods, respectively.

Table 3 presents the data according to the accuracy of the concentration of PVA in the proposed method (in conventional units - cu).

Table 1

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427502 751616

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127502 375 ± 28 15

table 2

As can be seen from Tables 1 and 2, for the proposed method and the known concentration of cells in the sample zone containing the toxicant, decreases with increasing concentration of the toxicant.

Thus, the proposed and. The known methods have the same character of the dependence of d1 on the concentration of the toxicant.

From Tables 1 and 2, the relative error of the proposed method is 15-16% with an optimal ratio of the weight of the suspension of the test culture and PVA, equal to 1: 0.07; by of

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To a known method, the relative error is 43–46%. A decrease in the concentration of PVA in the suspension of the test culture leads to an increase in the relative error to 27–31% (1: 0.004 ratio). A further decrease in the concentration of PVA is accompanied by a further increase in the relative error to the level according to a known method.

Example 1. Toxicant — copper sulfate — is indicated. Test concentrations of copper sulfate were prepared in Lozin-Lozinsky medium of the following composition, g / l: NaCl O, 1 KC10.01

MgSO 0.01 CaClj 0.01 NaHCGj 0.02 Paramecium caudatum is used as a test culture. The test culture of Paramecium caudatum is grown according to method 2, washed from the yeast with Lozina-Lozinsky medium in a centrifuge (3000 rpm, 5 min). A test culture with a concentration of 3000 cells in 1 ml of Lozin-Lozinsky medium is used.

A 5% PVA solution is prepared. Make a sample of PVA powder. 5 g. Put it in 95 (95 ml) of Lozin-Lozinsky medium (Scattering ratio g / MP 1,00015, therefore

weight units can be replaced by bulk).

PVA is left to swell in the liquid for a day, and then, since PVA is dissolved only in hot water, it is heated in a water bath at the boiling point for two hours. Get a clear solution of PVA, which is used for a week.

A 5% solution of PVA, the density of which was determined experimentally and was 1.03 g / ml, was added to the MO suspension of the test culture by volume. Legitimacy weight

dosing with the help of volumetric measures calibrated by water is caused by a small error (3%) and a wide working range of the concentration of PVA.

The test culture MO mixed with 5% solution of PVA. For 4.3 ml of Paramecium caudatum suspension, 0.7 ml of 5% PVA solution is added (mass ratio 1: 0.007). Pe-

Stir. 2 ml each is introduced into the control and experimental cuvettes. Sizes of a ditch are 40 10 10 mm. A sample is layered on top of the test culture. In the control cuvette - Lozin-Lozinsky medium, in the experimental one - CuSO solution in the same medium with a concentration of 6-10 mol / l. The sample volume is 2 ml. A setup is used to measure cell concentration (Fig. 1). The measurement is carried out according to the scheme in FIG. 1, either discretely to determine the dynamics of the chemotactic process, or 30 minutes after the completion of cell redistribution. An incandescent lamp (P 18 W) is used as a radiation source, the luminous flux from the lamp is supplied to cuvettes 3 and 4 through flexible fibers 2. Radiation from the cuvette is fed through another pair of optical fibers to the photodetector 9 and measured by measuring device 10. signals: I

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characterize the concentration of cells in the controlled areas of the control kuKak can be seen from the above examples and table. 3, the accuracy of the display is highest with a suspension ratio; microorganisms and polyvinyl alcohol, equal to 1: 0.007. The decrease in display accuracy at a ratio of 1: 0.004 is due to the fact that the viscosity of the liquid of the lower layer approaches the viscosity of the layered liquid, and the weight of

experienced, and their difference respectively. The measurement results are given in Table 1. The relative measurement error at a given ratio of test culture and PVA was 15%.

In parallel, an indication of copper sulfate was carried out by a known method. The data are given in table 2. The error of the known method was 43%.

Example 2. While maintaining all the conditions of the first example, the mass ratio of the suspension of microorganisms and polyvinyl alcohol is changed to the following: 1: 0.004. The relative error in this case was 27% (Table 3).

Example 3. While maintaining all the conditions of the first example, the ratio of the suspension of microorganisms and polyvinyl alcohol is changed to the following: 1: 0.01. The relative error in this case was 15% (Table 3).

Table 3

These samples without mixing with the lower layer become difficult, and mixing of the liquid layers disrupts the stabilization of the concentration gradient and decreases the accuracy of the indication by chemotactic .i reaction. With an increase in the ratio to 1: 0.01, the microorganism cells of the test culture do not fully migrate

Claims (1)

8 claims The method of indicating the pollution of environmental objects by chemicals according to author. No. 1010128, characterized in that, in order to demonstrate the accuracy of the indication, a suspension of the test culture of microorganisms is preliminarily mixed with a 5% aqueous solution of polyvinyl alcohol in a mass ratio of the suspension of microorganisms and a solution of polyvinyl alcohol 1: (0.004-0.01) respectively, Editor A.Gulko Tehred L. Serdazhova Cor Pod 7372/22 Circulation 500 VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, st. Project, 4 Proofreader S.Shekmar Subscription