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Pharmaceutical Analysis Pharmaceutical analysis Quality assurance of pharmaceuticals 02 Metrohm... • is the global market leader in titration • is the only company to offer a complete range of ion analysis equipment – titration, voltammetry, and ion chromatography • is a Swiss company and manufactures exclusively in Switzerland • grants a 3­year instrument warranty and a 10­year warranty on chemical suppressors for ion chromatography • provides you with unparalleled application expertise • offers you more than 1300 applications free of charge • supports you with expert service through local representatives and regional support centers • is not listed on the stock exchange, but is owned by a foundation • gives the interest of customers and employees priority over maximizing profit Metrohm − customized analysis for the pharmaceutical industry The regulatory authorities set high standards You can count on our support With regard to the quality and safety of drugs, authori­ As a leading manufacturer of instruments for chemical 03 ties worldwide set high standards for the pharmaceutical analysis, we are aware of these challenges. For this rea­ industry. These are documented in pharmacopoeias in son, Metrohm offers you not only the latest instruments, the form of official collections of recognized pharmaceu­ but complete solutions for very specific analytical issues. tical rules. As legal tools of consumer protection, they Your Metrohm contacts are competent specialists, who ensure that drugs are used safely. It is only the measuring will develop customized applications and provide you and test procedures used within the framework of drug with professional support in all matters of regulatory testing that identify a drug and determine whether it is compliance. approved or not. Discover on the following pages what solutions Metrohm To ensure these high quality and safety standards, reliable is able to offer the pharmaceutical sector in general and instruments and methods are needed. you in particular, to ensure the quality and safety of your products. Challenge us! Chemical pharmaceutical analysis The history of pharmacy Determination of active ingredients, excipients, 04 The search for remedies is as old as humanity itself. There and impurities is evidence that the first advanced civilizations (China, Pharmaceutical analysis provides information on the India, Mesopotamia, Egypt) were already using drugs of identity, purity, content, and stability of starting materi­ plant, mineral, and animal origin for medicinal purposes. als, excipients, and active pharmaceutical ingredients Systematic descriptions of remedies have been handed (APIs). A distinction is made between analysis of the pure down to us from Greek antiquity (Hippocrates, Theo­ active ingredients used to cure, alleviate, prevent, or phras­­­­tus) and from the Roman Empire (Dioscorides, identify illnesses and diseases (active ingredient analysis) Galen). This knowledge was adopted by Arabian scholars and analysis of medicinal preparations. The latter can (e.g., Avicenna) and was developed further. It served for exist in various forms (ointments, tinctures, pills, lotions, a long time as an important basis of medicine. It was not suppo s­­itories, infusions, drops, etc.) and consists of the until the 16th century that this began to detach itself pharmaceutically active substance and at least one phar­ from the ancient models. A typical representative of the maceutical excipient. Impurities usually stem from the new direction was Paracelsus, who, in 1537, coined the synthesis of the active ingredient; they are usually moni­ famous phrase: «Only the dose makes the poison» tored according to the guidelines of the ICH (International («dosis sola facit venenum»). Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use) and The way to organic synthetic drugs the pharmacopoeias. The emergence of organic chemistry at the start of the 19th century brought progress, the importance of which Pharmacopoeias to ensure the safety of drugs can hardly be overestimated. Whereas previously treat­ Specifications and test methods for the commonly used ment with drugs had been restricted largely to natural active ingredients and excipients are monographed in substances and inorganic chemicals, people now started detail in national pharmacopoeias in more than 38 states specifically to produce organic synthetic drugs, using according to the World Health Organization (WHO). They substances isolated from medicinal plants as the basis. include the United States Pharmacopeia (USP), the An unprecedented advance in pharmaceutical synthesis European Pharmacopoeia (Ph.Eur.), which emerged from led within a very short time to a vast number of synthe­ the harmonization of the regulations of a number of sized active ingredients. In this context, researchers in ­ individual states, and the Japanese Pharmacopoeia (JP), crea­­singly succeeded in establishing a relationship be­ to name but a few. The pharmacopoeias are official com­ t ween the action of these substances and their chemical pendia and contain the statutory requirements regarding structure. the identity, content, quality, purity, packaging, storage, and labeling for active pharmaceutical ingredients and other products used for therapeutic purposes, and are essential for anyone who wants to produce, test, or mar­ ket medicinal products. 05 Selected test methods and USP-NF monographs Metrohm is the competent contact for all matters con­ and monographs of the USP. The National Formulary (NF) cerning chemical­pharmaceutical analysis and the valida­ is the official compendium of standards for excipients tion of analytical methods. Apart from complying with and plant­based drugs. numerous official guidelines, Metrohm instruments and applications satisfy the test methods for quality control Structure of the USP-NF and product release that are listed in the most important Apart from the description of numerous analytical meth­ pharmacopoeias. ods in the general section of the USP­NF, the main section contains generally applicable standards for active ingredi­ In accordance with the harmonization efforts of the Phar­ ents (USP) and excipients (NF) in the form of monographs. ­­­macopoeial Discussion Group (PDG), the present bro­ More recent texts (since 1997) also contain a list of pos­ chure, taking the place of the pharmacopeias not men­ sible impurities (transparency list) that can be determined tioned here, relates primarily to selected test methods with the test methods described. Test methods referenced in USP-NF monographs (USP 32-NF 27) Parameter USP monograph Number of citations in the monographs Test method Page In 1328 USP monographs pH value USP<791> pH measurement 6 In 68 NF monographs Conductivity USP<645> Ultrapure water for pharmaceutical use Conductivity measurement 6 Various active ingredients In 127 USP monographs USP<541> Titration 7­9 Various excipients In 51 NF monographs USP<921> In 616 USP monographs Water content Karl Fischer Titration 10­11 Method I In 98 NF monographs Various active ingredients In 27 USP monographs USP<621>/USP<1065> Ion chromatography 16­17 Various excipients In 3 NF monographs Various active ingredients USP<801> In 8 USP monographs Polarography 18­19 Determination of Thimerosal USP<341> Polarography 19 antimicrobiotics pH value, conductivity, and parameters that can be Process­dependent Various Process analysis 20­21 determined by titration specifications and voltammetry 06 Water for pharmaceutical use (water for injection) pH value Conductivity measuring cell (stainless steel) with The 867 pH Module provides all that is needed for meas­ Pt 1000 uring the pH value according to USP<791>. With 900 This measuring cell was developed especially for measure­ Touch Control, or tiamoTM full, intelligent sensors, and ment in waters with very low conductivity. The robust five­point calibration it meets the requirements of FDA and easy­to­clean stainless steel construction is ideally regulation 21 CFR Part 11. In conjunction with 900 Touch suited for conductivity values <300 μS/cm, and thus for Control it is possible to carry out an electrode test. measuring water for pharmaceutical use. Conductivity and pH value can be measured in the same . vessel if the 856 Conductivity Module is combined with the 867 pH Module. Conductivity Particularly strict rules apply to the measurement of the conductivity of water for pharmaceutical use (water for injection) according to USP<645>. Apart from the highest level of precision, all the requirements of the U.S. FDA’s regulation 21 CFR Part 11 must be satisfied. The 856 Con­­ductivity Module, together with the 900 Touch Control, or tiamoTM full, guarantees this. PharmPAC – application know-how from experts Because of the simplicity and the accuracy of the proce­ Some older USP methods are still frequently based on dure, a large proportion of the content determinations high sample weights, which require a titrant consump­ 07 described in the monographs are carried out using titra­ tion of up to 50 mL. Following Ph.Eur., Metrohm has tion methods, for example, according to USP<541>. re­­duced the sample weights considerably and thus cut Taking into account the latest methodological knowl­ titrant consumption to at most 10 mL. edge, Metrohm has developed hundreds of titration methods with Metrosensors based on the U.S. Phar­­ma­ All the methods have been worked out in such a way copeia (USP) and European Pharmacopoeia (Ph.Eur.). that you can adopt them as SOPs
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