Auxiliary substances

Use safer solvents. Minimal use should be made of solvents, separation agents, and other auxiliary substances in a reaction. 

The use of auxiliary substances (e.g., solvents or separation agents) should be made unnecessary whenever possible and innocuous when used. 

In the first group the titrant is generated either directly from a participating or active electrode, or indirectly from an inert or passive electrode, in which case it is necessary to add previously an auxiliary substance that generates the titrant by either cathodic reduction or anodic oxidation the end-point detection is usually potentiometric or amperometric. The following selected examples are illustrative of the first group in non-aqueous media ... 

The gaseous product (SF6) does not interfere with the analysis of solids that form in the main bomb process. Furthermore, the contribution of reaction 7.82 to A f/jgp can be accurately calculated lfom the mass of sulfur and the value of ArC/°(7.82) at 298.15 K [124], It may also be necessary, in some cases, to use an auxiliary substance to promote complete combustion of the compound under study [111,113]. Tungsten is a very common combustion aid it reacts cleanly with excess fluorine according to... 

Dz. U. (2003). Newsletter of Current Legislation 37, 326. [The Instruction of the Polish Minister of Health on 13 th January 2003 regarding maximum levels of chemical and biological contamination that may be present in food, food components, allowed additional substances, auxiliary substances applied in processing or on food surfaces.]... 

In February 1909, the results of the experiments on nitride formation had led to the outline of a patent application which covered the preparation of metal nitrides in the presence of auxiliary substances. Following a hypothetical concept of the action of these additions, they were defined as flux promoters." This draft of an application ended with the following sentence Finally, it is also advantageous to add a flux promoter to metals or alloys which serve as catalysts for the ammonia synthesis. This statement was made in view of the early catalytic experiments in which we had observed the synthesis of traces of ammonia in the presence of catalysts similar to those which acted favorably for the nitride formations. 

A number of ACE assays dealing with the characterization of interactions between cyclodextrines as auxiliary substances and drugs have been presented. Other authors put more emphasis on the description of separation phenomenona by determination of binding constants. Model substances such as phenols are often used to examine the influence of ligand size and substitution as well as to evaluate the mathematical approaches for the calculation of binding constants. 

Safer solvents and auxiliaries Auxiliary substances—solvents, separation agents, and others—should be made unnecessary wherever possible and innocuous when used. 

In the case of an active substance at very low dose, i.e., requiring a high dilution with the auxiliary substances (e.g., 1 100), the blending operation may be divided into two steps primary 1 10 dilution and then a second 1 10 blending step in order to obtain the final dilution. 

Dry blending of the primary powder material, i.e., active substance and auxiliary substances in a mixer. Preference should be given to demineralized water as granulating liquid and the excipients and the drug should show relatively low water solubility with the exception of the binder. The binder should be preferably added in a dry state as part of the powder components. 

International classification C08B37/00, C12N9/96, C12N11/10 The invention relates to an auxiliary substance to accompany an active substance, such as a pharmacon. The auxiliary substance has a stabilizing action and a positive influence on the bioavailability of the active substance within pharmaceutical preparations. The auxiliary substance is based on a fructan (inulin of degree of polymerization (DP) over 6), obtained from Jerusalem artichoke or other sources. 

Much ingenuity has been exercised by chemists in attempts to effect this change through a series of reactions. In the older Le Blanc soda process sulphuric acid is used in the first step and coal (carbon) in another, and neither of these auxiliary substances is recovered. The soda process which is employed exclusively today is known as the Solvay or ammonia process and uses ammonia as an auxiliary substance. The ammonia is almost 100 per cent recoverable, however, and can be used over and over indefinitely. The successive steps in the process are as follows ... 

Only for some of the radical reactions discussed in Sections 1.6-1.9 is the initiating radical produced immediately from the starting material or the reagent. In ah other radical substitution reactions an auxiliary substance, the radical initiator, added in a sub-stoichiometric amount, is responsible for producing the initiating radical. 

From this equation it is obvious that water is the only raw material in the manufacture of hydrogen peroxide. The other chemicals H2S04, (NH4)2 S04 etc. are auxiliary substances which return to the production cycle and are added only in an amount necessary to replace mechanical losses. 

All information available at present is presented in the 15 chapters of the special part. From lipides, vitamins, sterols, via medicaments, auxiliary substances of the industry, amino and nucleic acids, to anion- and cation-separation — every subject is dealt with. The possible new applications of the method in medical diagnosis and pharmacology are described in a special chapter. The authors of the respective chapters, after having employed the method for years, report also on the results of their own work some of this information has not been published before and will save time-consuming preliminary tests and studies of literature, for beginners and specialists and will give valuable hints. 

Avoid using solvents, separation agents, or other auxiliary chemicals. If these chemicals are necessary, then use innocuous chemicals. In the manufacture, processing, and use of chemicals, auxiliary substances are utilized at every step. An auxiliary substance aids in the manipulation of a chemical or chemicals, but it is not an integral part of the target molecule itself. This is the case of solvents and separation agents. Solvents play many crucial roles in the synthesis of chemical products. Those most evident are as reaction media and as factors in product separation and purification (i.e., solvents for recrystallization, mobile and stationary phases for chromatographic separations, and the like). 

In order to select conditions for the separation of any mixture of substances it is necessary to consider three separate groups of questions (i) What type of ion exchanger What solvent What should the concentration of the treated solution be to obtain an equilibrium separation coefficient, a, as different from unity as possible (ii) What process scheme will minimize expenditures for auxiliary operations such as the regeneration of resin and auxiliary substances (iii) What equipment will be most effective and efficient ... 

Edimo A, Leterme P, Denis J, et al. Capacity of lipophilic auxiliary substances to give spheres by extrusion-spheronisation. Drug Dev Ind Pharm 1993 19 827-842. 

Sample preparation represents a formidable challenge in the chemical analysis of the real-world samples. Not only is the majority of total analysis time spent in sample preparation, but also it is the most error-prone, least glamorous, and the most labor-intensive task in the laboratory. The components to be separated from the matrix are usually taken up with an auxiliary substance such as a carrier gas, an organic solvent, or an adsorbent. These separation processes can be regarded as extraction procedures (i.e., liquid-liquid extraction, liquid-solid extraction, Soxhlet extraction, solid-phase extraction, supercritical fluid extraction, solid-phase microextraction, etc.). 

In 1978, a loose-leaf spectra collection entitled "UV and IR Spectra of Some Important Drugs" first appeared, which until 1998 was expanded by several supplements. In 1987, a second collection was published "IR Spectra of Pharmaceutical and Cosmetic Auxiliary Substances". 

We endeavoured to select typical and often used representative substances for particular classes of compounds. These then can be used as representatives for similar compounds. This also is the reason why the number of substances covered here is rather low compared with some lists of excipients such as, e. g., Fiedler Encyclopedia of Excipients or Index der Hilfsstoffe/Index of Auxiliary Substances by H. P. Fiedler. It would not have been meaningful to include numerous, very similar substances - all showing virtually identical IR spectra. 

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