Test solution preparation

Initial experiments showed that [0s(ri6-bip)Cl(en)]+ (26) was not cytotoxic towards cancer cells (105), but a later reassessment of the cytotoxic activity of this compound showed that it indeed was active at micromolar concentrations (IC50 values of 7.6 (A2780) and 10 pM (A549)) (112). A possible explanation for the initial lack of activity may be the partial decomposition of the complex in stock test solutions prepared in DMSO, as was evidenced in subsequent studies (112). The cytotoxicity data are now more in line with the chemical properties of the complex, i.e. observed hydrolysis rate and guanine binding. 

The test solution prepared as specified, is placed in the wide-mouthed bottle, 1 g of KI (AsT) and 10 g of Zn (AsT) are added, and the prepared glass tube is placed quickly in position. The reaction is allowed to proceed for 40 minutes. The yellow stain that is produced on the HgCl2 paper if As is present is compared by daylight with the standard stains obtained by performing in an identical manner with known quantities of dilute arsenic solution (AsT). The comparison of the stains is made immediately at the completion of the test. 

The ruggedness was examined on a test solution prepared from a tablet. Each of the factors was tested at three levels. The factors and their levels... 

Accuracy. In the quantitative method that is used to measure the heavy metal quantity in the drug substance, the accuracy is usually represented by the recovery rate obtained from a spiked recovery test where lead is added to the samples. Since the heavy metals limit test specified in monograph specifications is a test where the intensity of coloring of the samples with sodium sulfide is compared with that of the control solution, it is necessary to confirm that heavy metal components can be detected fully in the process of test solution preparation. The Heavy Metals Limit Test in JP specifies four preparation methods for the test solutions. An appropriate method will be selected and used for further testing. The test method that gives the best recovery rate is to be adopted. The procedure is as follows ... 

Test solution Prepare a solution of Omeprazole in Solvent containing 50 mg/ml. 

Test Solution Prepare a 6% solution of sample in chloroform. 

Test Solutions Prepare at least four test solutions, each containing the colorant, and one impurity, accurately weighed, dissolved in 0.1 M Na2B407, and diluted to volume in a 100-mL volumetric flask. The solutions should encompass the range of concentrations, evenly spaced, given below for each constituent ... 

Test Solution Prepare a solution from the enzyme preparation so that 2 mL of the final dilution will give a AA in the Procedure between 0.2 and 0.5. Weigh the sample accurately, transfer it quantitatively to a glass mortar, and triturate with Phosphate-Cysteine-EDTA Buffer Solution. Transfer the mixture quantitatively into a volumetric flask of appropriate size, dilute to volume with Phosphate-Cysteine-EDTA Buffer Solution, and mix. 

Chloride <103> To 10 mL of the sample solution obtained in soluble salts test, add 6 mL of dilute nitric acid, dilute with water to 50 mL, and perform the test using this solution as the test solution. Prepare the control solution with 0.75 mL of 0.01 mol/L hydrochloric acid VS (not more than 0.053%). 

Heavy metals <1.07> To 1.0 g of magnesium silicate add 20 mL of water and 3 mL of hydrochloric acid and boil for 2 min. Filter, and wash the residue on the filter with two 5 mL portions of water. Evaporate the combined filtrate and washings on a water bath to dryness, add 2 mL of dilute acetic acid to the residue, warm imtil solution is complete, filter, if necessary, add water to make 50 mL, and perform the test using this solution as the test solution. Prepare the control solution with 3.0 mL of standard lead solution, 2 mL of dilute acetic acid and water to make 50 mL (not more than 30 ppm). 

The calibration is established from solutions prepared by diluting a solution of I 000 mg/1 of the element to be determined. When sample solutions are prepared using the fusion method, the reference solutions used for this analysis contain the same quantity of lithium metaborate as the sample solution. The origin of the calibration curve is determined by a blank test solution prepared in the same way as the standards, but without the element to be determined. 

The USP 24/NF 19, section 201 (Ref.f p. 1856), contains a general TLC identification test that involves a non-high-performance silica gel layer with fluorescent indicator, chloroform-methanol-water (180 15 1) mobile phase, and detection under 254 nm UV light for verification of the identities of compendial drugs in dosage form test solutions prepared according to the individual monographs. Section 621 of the USP 24/NF 19 (Ref. pp. 1916-1917) presents brief information... 

The test solution prepared from analytical grade NaCl (GOST 4233-77) conductivity of deionised water not checked Cu and Ni determined by AAS and both met the requirements of ISO 9227 the pH of the prepared solution measured with millivoltmeter pH-121... 

Heavy metals To determine the heavy metal content, the test solution prepared above is used in general test <231 >. The limit is 0.004%. 

Filter a testing solution prepared from tannin extracts from the raw or spent materials on a standard filter paper. Pipette 50 ml of the filtrate to a preweighed beaker with stopper. Dry the testing solution overnight in a forced-air oven at 100 2 °C. Cool the beaker with the stopper in a desiccator. Weigh the beaker containing the solid residue. The solid residue converted to each litre of the filtrate is defined as the total soluble solids of the testing solution (g 1 ). 

Then without having added any sample, heat to about 40°C and titrate with 0.01 M sodium edetate xmtil the violet color changes to full blue. The test solution prepared in step one contains both zinc and the indicator Erio-chrome Black and it will form a violet complex. But when the test solution is titrated with EDTA in the second step of analysis the stronger EDTA complex will deplete zinc ions of tiie solution and the indicator complex making it change the color to its metal free blue form, since titration is carried out to blue and EDTA is complexed with zinc. 

Procedure. The test is conducted in a micro crucible. One drop of the test solution (prepared by dissolving the carbonate precipitate in dilute hydrochloric acid) is taken to dryness and about 0.5 g of solid ammonium sulfate is added to the residue. The contents of the crucible are heated gradually and finally brought to a temperature sufficient to drive off the ammonium sulfate completely (no more white fumes). The cold mass is treated with a drop of sodium rhodizonate solution and one drop of dilute alkali (see above). Depending on the quantity of calcium present, the white precipitate is tinted more or less violet. 

Flow signals obtained for chlorogenic acid are shown in Figure 36.4. The response was linear between 5.0 x 10 and 3.0 x 10 M [5,15]. The FIA-ECD method was examined in detail for determining the acid content in coffee. In the test solution preparation, 250 mL of hot water was poured onto 20 g coffee powder on a filter paper, and the filtrate was diluted with an ethanol solution containing 3 mM VKj and 38 mM LiC104 [5,15]. 

Blank solution Use the reagent blank referred to in the text, Le., a test solution prepared identically to the sample test solution omitting only the addition of sample at the Kjeldahl digestion stage in the determination. To determine the magnitude of the blank optical density (as a check the reproducibility obtained in duplicate determinations), measure the optical density of the blank solution at 625 nm relative to distilled water in the comparison cell. 

Measure 2 ml of the standard solution (prepared by dissolving 10 mg of crystalline tubocurarine chloride in water and making up to 100 ml) or 2 ml of the test solution (prepared by diluting the solution under examination to approximately the same concentration as the standard) into a 25-ml glass-stoppered measuring cylinder. Add 3 ml of Folin and Ciocalteu s phenol reagent (see p. 476) and adjust the volume to 25 ml with water. Add 2 ml of 20 per cent sodium carbonate solution, mix and heat a suitable volume (5 ml) in a test-tube placed in a water-bath for three minutes. Cool the reaction mixture. 

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