57359 - Analysis of Medicines I (GR.B)

Learning outcomes

The student acquires theoretical and practical knowledge for analytical laboratory work, in particular for the identification and quantitative determination of inorganic drug-related compounds by means of chemical reactions and volumetric titrations. He will then be able to apply this knowledge for the determinations via the different methods reported in the European Pharmacopoeia or Italian FU, to search for alternative methods applying all acquired knowledge. He will possess skills that allow communication with analytical-pharmaeutical specialists and ability to integrate presently acquired knowledge with previously studied subjects in order to proceed to the following steps of his studies. The course includes individual laboratory activity.

Course contents

Introduction. Aim of the course. Introduction to qualitative and quantitative analysis . The Italian Official Pharmacopoeia (F.U.) and the European Pharmacopoeia (E.P.). Safety in the laboratory environment.

Introduction to drug analysis. Solubility. Solution properties. Solubility product. Formation and dissolution of precipitates, co- and postprecipitation. Crystals, colloidal precipitates and their characteristics. Periodic table.

Qualitative analysis

Cations. Properties, biologically active compounds, biological roles, toxicological aspects and reactions used to identify the following cations: Silver, Lead, Mercury, Arsenic, Antimony, Bismuth and Copper. How to calculate the pH of precipitation of sulphides. How to calculate the pH of precipitation of hydroxydes Common properties of transition metals. Properties, biological roles, biologically active compounds, reactions of Aluminum, Iron, Zinc, Manganese, Nickel and Cobalt. Common properties of alkaline earths. Calcium, Barium and Magnesium: properties, biological roles, biologically active compounds, reactions. Common properties of alkali metals. Sodium, Lithium and Potassium: properties, biological roles, biologically active compounds, reactions. Ammonium ion. Systematic analysis of cations. Principles of color theory. Flame test.

Anions. Halides: common properties. Chlorides, bromides and iodides: properties, biological roles, biologically active compounds, reactions. Properties, biological roles biologically active compounds, reactions of Acetates, Borates, Sulphates, Phosphates, Carbonates and Bicarbonates, Sulphides and Thiosulphates, Nitrates, Oxalates. Iodine. Hydrogen peroxide. Introduction to complex ions. Limit tests.    

Introduction to volumetric analysis. Glassware and its use. Electronic balances. Concentration units. Normality, equivalents, calculus in volumetric analysis. Standard solutions. Primary standards, their properties and use.

Quantitative analysis

Acid-base titrations . Titration curves of acid and bases. Indicator theory. Common acid-base indicators and their use. How to choose a suitable indicator. Mixed indicators. Acid and base standard solutions used in volumetric analysis. Primary standards used in preparing and standardising acid and base solutions. Examples of acid-base titrations according to E.P.

Precipitation titrations . Precipitation titration curves. Common precipitation indicators and their use. Standard solutions used in precipitation titrations. Determination of halides by Mohr's, Volhard's and Fajans' methods. Practical aspects, limitations and applicability of the methods. Examples of precipitation titrations according to E.P.

Redox titrations. Introduction and theoretical aspects. Redox titration curves. Redox indicators and specific indicators. Permanganometry. Properties, reactions and use of permanganate solutions. Identification of the final point. Standardisation of permanganate solutions. Examples of permanganometric titrations according to E.P. Iodimetry. Preparation and use of iodine solutions. Examples of iodimetric titrations according to E.P. Iodometry. Principles, applications, properties. Use of starch water as an indicator. Examples of iodometric titrations according to E.P. Cerimetry. Properties and preparation of Ce4+ solutions. Examples of cerimetric titrations according to E.P.

Complex-formation titrations . Complex-formation and instability constants. Complexometric titration curves. Titrations employing EDTA. Conditional formation constant, a and their relationship to pH. Indicators for EDTA titrations. Direct titrations, back-titrations, displacement titrations, titrations based on indicators for an added metal ion, indirect titrations. Masking agents, masking and demasking. Analysis of complex cations mixtures. Water hardness. Examples of complexometric titrations according to E.P.

LABORATORY

Qualitative analysis

Reactions used to identify the cations: Silver, Lead, Mercury, Antimony, Bismuth, Copper, Aluminum, Iron, Zinc, Manganese, Calcium, Barium, Magnesium, Sodium, Lithium, Potassium, Ammonium ion. Flame test.

Reactions used to identify the anions: Chlorides, Bromides, Iodides, Acetates, Borates, Sulphates, Phosphates, Carbonates and Bicarbonates, Nitrates, Oxalates. 

   

Quantitative analysis

Standardization of HCl and of NaOH. Purity of acid compounds according to F.U.

Standardization of AgNO3. Purity of NaCl.

Standardization of Na2S2O3 and of KMnO4. Purity of redox compounds according to F.U.

Standardization of EDTA. Purity of ZnO.

The unknown concentration of inorganic ion solutions will be determined during the lab course.

Readings/Bibliography

Qualitative analysis:

P. Barbetti, M.G. Quaglia

L'Analisi qualitativa in chimica farmaceutica e tossicologica inorganica

Galeno Editrice

 

Quantitative analysis

D. S. Hage, J. D. Carr

Chimica Analitica e Analisi Quantitativa

Piccin ed. (2012)

 

G.C. Porretta

Analisi di preparazioni farmaceutiche - Analisi quantitativa

CISU ed.

Teaching methods

The course takes place during the second semester and is divided in two modules; each module consists of 32 hours (4 ECTS Credits) of lessons and 36 hours (3 ECTS Credits) of laboratory practice; attendance is mandatory.

Qualitative analysis module (Prof. Silvia Gobbi): identification reactions of inorganic active principles according to F.U. are explained and applied during laboratory practice.

Quantitative analysis module (Prof. Roberto Mandrioli): volumetric analysis is explained and applied during laboratory practical for the purpose of drug purity controls and inorganic active principle determinations.

Laboratory practical is carried out individually, with a final test.

Assessment methods

The proof consists of an oral examination concerning both teaching modules, aiming to verify the knowledge acquired as stated by the objectives of the course. This examination, which could also include the reading and discussion of some of the monographs of the European Pharmacopoeia, shall be considered positive on the basis of the correct answer to questions related to topics covered during the course.

Since the course includes practical exercises regarding the determinations described in the European Pharmacopoeia, the results obtained in such exercises will contribute to the definition of the final grade.

Teaching tools

The theoretical lessons will be held by using PowerPoint slides. The practical activity will be carried out in laboratories equipped with chemical reagents and analytical instrumentation.

Office hours

See the website of Roberto Mandrioli

See the website of Silvia Gobbi