Learning objectives
The course aims to provide students with a thorough knowledge of major instrumental analytical techniques, including spectroscopic techniques, separation techniques, hyphenated techniques and electroanalytical techniques. A critical discussion of equipments, procedures and interpretation of test results is emphasised.
Prerequisites
Physics I. Physics II. Analytical Chemistry and Laboratory of Analytical Chemistry.
Course unit content
Introduction to instrumental analytical methods
Classification of analytical techniques
Criteria for the choice of analytical methods.
Method performance characteristics: linearity, sensitivity, limit of detection, limit of quantitation, accuracy (trueness and precision), selectivity.
Calibration methods: external standard method, standard addition method, internal standard method.
Spectroscopic techniques
Fundamentals of spectrophotometry.
Molecular Absorption and Fluorescence UV-vis Spectrophotometry. The nature of electronic transitions. Instrumentation for molecular absorption UV-vis spectrophotometry: sources, monochromators (prism, diffraction grating), detectors. Photodiode array detector. Definition of trasmittance and absorbance. Lambert-Beer law and deviations. Applications to quantitative analysis. Instrumentation for molecular fluorescence UV-vis spectrophotometry. Effect of temperature on the fluorescence quantum yield.
Molecular Absorption IR Spectrophotometry. Modes of molecular motion; vibrational modes and absorption regions. Factors that influence the frequency of absorption. Characteristic IR absorption frequencies. Instrumentation: FT-IR spectrophotometer. Applications of IR spectrophotometry to the characterization of organic compounds.
Atomic Absorption Spectrophotometry. Atomic spectra. Instrumentation: hollow cathod lamp, atomizers (flame atomizer, graphite furnace). Spectral and non spectral interferences. Background correction systems.
Atomic Emission Spectrophotometry. Instrumentation: ICP source, high-resolution monochromators, detectors.
Mass Spectrometry. Fundamentals. Instrumentation: electron ionization source, chemical ionization source, analyzers (magnetic sector, quadrupoles, ion trap, time-of-flight), detector.
Separation techniques
Theory and application of chromatography. Gas chromatography and liquid chromatography.
Chromatographic parameters. Retention time. Capacity factor. Selectivity factor. Resolution. Band broadening and column efficiency.
Gas chromatography. Gas-solid chromatography (GSC). Gas-liquid chromatography (GLC). Stationary phases for GSC and GLC. Instrumentation: injectors, columns, detectors. Capillary columns. Universal and selective detectors. Gas chromatography-mass spectrometry. Isothermal gas chromatography. Temperature-programmed gas chromatography. Internal standard calibration method for quantitative determinations.
Liquid chromatography. Mechanisms of separation: adsorption chromatography, partition chromatography, ion chromatography, size-exclusion chromatography. Instrumentation for HPLC: injection valve, columns, pumps, detectors. Isocratic elution, gradient elution.
Laboratory activities related to applications of spectroscopic and chromatographic techniques for qualitative and/or quantitative analysis
Full programme
Introduction to instrumental analysis methods. Classification of analytical techniques. Criteria for choosing analytical methods. The analytical process. Method validation and quality parameters of analytical methods according to European guidelines: range of linearity of response, limit of detection, limit of quantitation, sensitivity, selectivity, precision, trueness.
Methods for determining concentrations; calibrations with external standards, standard addition method; internal standard method.
Fundamentals of analytical spectroscopy. Absorption and emission spectra, molecular and atomic spectra. UV-visible molecular absorptiom spectroscopy. Relationship between electronic structure and spectral bands. Instrumentation: sources, monochromator, detectors. Diode array detector. Definition of transmittance and absorbance. Lambert-Beer law: calibration curve to estimate the analyte concentration of a test solution; deviation from linearity. Absorbance measurements. Errors in absorbance measurements.
UV-visible molecular fluorescence spectroscopy. Fluorescence and phosphorescence. Instrumentation. Effect of temperature and of pH on fluorescence. Quantum efficiency and fluorescence emission: quantitative analysis.
Fundamentals of atomic spectroscopy. UV-visible atomic absorptiom spectroscopy. Origin of atomic spectra, instrumentation: sources, atomization systems, background correction systems. Spectral and non-spectral interference.
UV-visible atomic emission spectroscopy. Instrumentation: ICP source, high resolution monochromators, detectors.
Fundamentals of IR molecular absorption spectroscopy.Vibrational modes. Factors affecting vibrational frequencies and IR Spectroscopy of organic compounds. Instrumentation: FT-IR spectrophotometer. ATR- FT-IR spectrophotometer. IR spectra and characterization of organic compounds.
Fundamentals of mass spectrometry. Instrumentation: ionization sources (EI, CI, ESI), mass analyzer (magnetic sector, quadrupole, ion trap. time of flight analyzers). Resolution, mass accuracy.
Separation techniques. Basics of chromatography. The chromatographic peak. Retention time. Capacity factor. Selectivity. Resolution. Separation efficiency.
Gas chromatography. Gas-solid chromatography. Gas-liquid chromatography. Instrumentation: injectors, capillary columns, detectors. Universal and selective detectors. Isothermal and gradient-temperature analysis. Quantitative analysis: internal standard method. Gas chromatography-mass spectrometry.
Liquid chromatography. LC techniques: adsorption, partition, ion exchange, size exclusion chromatography. The choice of the most appropriate LC technique to face an analytical case. HPLC. Instrumentation: pumps, injector, columns, detectors. Isocratic and mobile phase gradient elution modes. Liquid chromatography-mass spectrometry.
Laboratory activities related to:
- UV-visible molecular absorption spectroscopy
- UV-visible atomic emission spectroscopy
- gas chromatography
- liquid chromatography
Bibliography
Daniel C. Harris, Chimica Analitica Strumentale, terza edizione (2017), Zanichelli, ebook, https://online.universita.zanichelli.it/harris3e/
Holler, Skoog, Crouch, Chimica Analitica Strumentale, II edizione, EdiSES, 2009
Teaching methods
Academic teaching (8 credits = 64 hours).
Laboratory exercises are aimed at the practical application of theoretical knowledge acquired during face-to-face lessons (1 CFU = 15 hours). The
explanation of each exercise will be carried out in a specific classroom lesson: attendance of these lessons will be mandatory like the laboratory exercises.
Assessment methods and criteria
The knowledge acquired and the ability to understand the concepts covered are verified through a WRITTEN and ORAL EXAMINATION.
The WRITTEN EXAM is WITH OPEN QUESTIONS on all the topics of the program and is subject to an initial evaluation with assignment of a score.
Students must complete the writing in an assigned time and space.
The ORAL EXAMINATION focuses on the discussion of the written test with the Commission and on other parts of the program that were not covered by the written test.
The Jury ranks the candidate and it decides the final evaluation, which takes into account also a rank given to the lab reports and the score of the written exam.
Evaluation on:
- learning of the basic concepts and tools of instrumental analytical chemistry.
- correct classification of analytical methods.
- critical evaluation of instrumental analytical techniques in terms of principles, scope and performance
- critical evaluation of the quality parameters of analytical methods
- acquisition of a formally correct language, ability to express the contents clearly, elaboration of links between the different parts of the course.
Other information
Support activities:
a) Illustration of case studies related to the application of instrumental analytical techniques in the food, environmental, biological and forensic fields.
b) Virtual learning environments as complementary educational tools.
Fundamental will be the use of the material distributed by the teacher which is projected in the classroom during the lessons and which is made available online.
The Syllabus of the Course will be illustrated and examined for everything concerning the following aspects:
-course content
-reference books
-learning goals
-entry requirements
-teaching methods
-assessment method
At the end of the illustration, the teachers will take care to verify the correct understanding of the Syllabus of the Course.
2030 agenda goals for sustainable development
3. Salute e benessere
