Solubility tests procedure

Other New Methods. Because the values obtained are dependent on the conditions of measurement, standard test procedures are under review by ISO for determination of cold-water solubiUty of water-soluble dyes (38) determination of the solubiUty and solution stabiUty of water-soluble dyes (39) and determination of the electrolyte stabiUty of reactive dyes (40). 

Earlier in this paper studies were reported that indicated correlation of the molecular structure of the compound with bioactivity in seed germination in laboratory tests, as compared to tests performed in the field, offer distinct advantages. Most of what we know on this subject was obtained from laboratory test procedures. Results from field tests are also dependent upon the stability of the compound and physical factors such as solubility and adsorption in the soil. 

Dissolution test data will be required in all cases (and for all strengths of product) for development and routine control and should be based on the most suitable discriminatory conditions. The method should discriminate between acceptable and unacceptable batches based on in vivo performance. Wherever possible Ph Eur test methods should be used (or alternatives justified). Test media and other conditions (e.g., flow through rate or rate of rotation) should be stated and justified. Aqueous media should be used where possible and sink conditions should be maintained. A small amount of surfactant may be added where necessary to control surface tension or for active ingredients of very low solubility. Buffer solutions should be used to span the physiologically relevant range—the current advice is over pH 1 6.8 or perhaps up to pH 8 if necessary. Ionic strength of media should be reported. The test procedure should employ six dosage forms (individually) with the mean data and a measure of variability reported. 

One may first check qualitatively whether the desired reaction has taken place, especially by means of solubility tests and NMR or IR spectroscopy it is also necessary to examine whether unreacted groups, or groups other than those desired, are present. Quantitative analysis is aimed at evaluating the proportions of A, C, and D in Eq. 5.2, for which one may employ not only the usual methods of determination, but also special procedures, such as spectroscopy and pyrolysis gas chromatography. It is also sometimes expedient to choose the low-molecular-weight reactant so that an easily determinable element is introduced (e.g., by using chloroacetic acid for esterifications). 

This section includes representative examples of the major types of reactions that are encountered in bisbenzylisoquinoline alkaloid research. Some of this material is not otherwise covered in this work. Diagnostic procedures, such as solubility tests and color reactions, are not considered. 

The block copolymerization was carried out following the same general procedure as that used for the chain-extension of a,co-dihydroxy-terminated oli-go(propylene succinate). The molecular weights and molecular weight distributions of the polymers obtained, as well as their transition temperatures, are recorded in Table 7. Solubility tests performed on SP-PEG copolymers obtained... 

Note The following Requirements and Tests apply to the Pectins as supplied, whether standardized or not, except for specifications covering amide substitution and the weight percent of total galacturonic acid in the Pectin component, in which cases the test procedures include provisions for removing the sugars and soluble salts before analysis of the Pectin component. 

Quantitative tests for RDX are described in this Volume under Cyclotrimethylenetrinitramine (RDX), Analytical Procedures Xy Alkali Solubility Test. Shake ca 0,5g of the sample for 2mins in a test tube with 5ml of 10% NaOH soln, filter and acidify the filtrate with coned HCl, Cool the tube under tap w, and rub the inside of the tube with a glass rod, A white ppt, appearing after about 5mins, is a positive test for EDNA and its presence can be confirmed by treating the sample with Thymol Reagent - a brown color is a positive test for EDNA (See also Chart B)... 

Plan a procedure for separating 2.0 g of the mixture into its components and have the plan checked by the instructor before proceeding. A flow sheet is a convenient way to present the plan. Using solubility tests, select the correct solvent or mixture of solvents to crystallize 4-chloroaniline. Determine the weights and melting points of the isolated and purified products and calculate the percent recovery of each. T urn in the products in neatly labeled vicils. 

The object of the present experiment is to identify an unknown amine or amine salt. Procedures for solubility tests are given in Section 1. 

The drugs listed in the EML were classified according to the criteria explained above. Where no clear classification could be made, the worst case was assumed. For example if a substance is highly soluble, but absolute bioavailability data were not available, the test conditions for BCS Class III substances have been proposed. The same procedure was adopted for fixed combinations, for example amoxicillin and clavulanic acid, the testing procedure was always fixed according to the worst BCS classification, in this example clavulanic acid (BCS Class III/l), because amoxicillin is a BCS Class I drug. This combination would therefore be tested according to BCS Class III requirements. The results of the revised classification can be found in Tables 1-3. 

Depending on the BCS classification of the API, based on solubility and permeability characteristics listed in the accompanying tables, the testing procedure is defined in section 9.2.1 of the Multisource document ... 

B) Natural fiber solubility tests Here the same general procedure and test tube set-up will be used except that we will be testing the solubility of three natural fibers - cotton, wool and silk in two solvents ... 

Digestion by boiling in the presence pf 30% hydrogen peroxide (Jackson (8)) yielded incomplete recoveries of total soluble phosphorus from all the estuarine water samples tested and from organic media such as Difco tryptone and peptone. Moreover, the method failed to yield quantitative recovery of an orthophosphate standard carried through the test procedure. 

In order to better clarify the importance of temperature on the preoxidation step, a solubility test was performed after this procedure, as described in Sections 2.3 and 2.4. The results are presented in Table 4. 

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