Interfaces and Colloids

Code:

Q4110

Acronym:

Q4110

Level:

400

Keywords
Classification	Keyword
OFICIAL	Chemistry

Instance: 2021/2022 - 2S

Active?	Yes
Course/CS Responsible:	Master in Biochemistry

Cycles of Study/Courses

Acronym	No. of Students	Study Plan	Curricular Years	Credits UCN	Credits ECTS	Contact hours	Total Time
M:BQ	2	Plano de Estudos do MBIOQ_2013-2014	1	-	6	56	162

Teaching language

Suitable for English-speaking students
Obs.: Caso haja estudantes internacionais que não dominem a língua portuguesa, as aulas poderão ser parcialmente lecionadas em língua inglesa. Os materiais de apoio pedagógico são disponibilizados em língua portuguesa ou inglesa.

Objectives

This course aims at familiarizing students with the basic concepts and foundations in the area of colloidal systems, soft materials and interfaces, and their direct application in the description and understanding of products, processes and techniques used in everyday life, in industry, in pharmaceutical and biomedical applications, in nanoscience and nanotechnology, and modern technology in general.

Learning outcomes and competences

At the end of the course, the students should  be able to identify different types of colloidal systems and their generic properties and to know the main physicochemical aspects that characterize interfaces. They should also be able to rationalize structure-function relationships and to understand the basics of some experimental techniques of characterization of colloidal and soft materials. The course also intends that the students develop independent research skills and are able to communicate and share scientific information and knowledge.

Working method

Presencial

Program

I - Theoretical classes

1. Fundamental concepts of colloids, interfaces and soft materials
- Colloidal systems, interfaces and soft materials: definition; interdependence; colloidal scale.
- Colloidal dispersions, self-assembled systems and macromolecules in solution – main properties.
- Shape, size and polydispersity of colloidal particles. Area/volume ratio; interfacial tension, work of cohesion and work of adhesion.
- Transport, electrical, optical and rheological properties of colloidal systems.
- Surfactants, lipids, self-organized systems, biological interfaces.
- Hydrophobic effect and its importance.
- DLVO theory and colloidal stability: electrostatic interactions; zeta potential; van der Waals interactions; coagulation and flocculation.

2. Interfacial phenomena: surface tension, capillarity, adsorption and wetting
- Liquid-gas and liquid-liquid interfaces: surface and interfacial tension; measurement methods; curved surfaces and capillarity; Laplace-Young equation and Kelvin equation.
- Surface excess properties; Gibbs adsorption model; Gibbs adsorption isotherm. Molecular films, monolayers and their applications.
- Solid-liquid and liquid-liquid interfaces: wetting and spreading; contact angle and Young's equation; hysteresis; modification of the wettability properties of surfaces.
- Solid-liquid and solid-gas interfaces: adsorption phenomena and main adsorption isotherms (Langmuir, Freundlich and BET).
- Biomembranes and biological interfaces.

3. Self-assembled systems and materials: structure, properties and applications
- Physical and thermodynamic fundamentals of aggregation; rationalization models: critical packing parameter and spontaneous curvature. Effect of different physicochemical parameters on self-aggregation.
- Micelles: structure and properties; critical micellar concentration (cmc) and Krafft temperature; thermodynamics of micellization; factors influencing cmc; micellar shape, growth and solubilization.
- Bilayers, liposomes and biological membranes – composition, structure and dynamics: phase transitions; applications.
- Liquid crystals and related structures. Microemulsions and Emulsions. Foams.
- Phase diagrams of systems based on surfactants and lipids - rationalization and practical importance.

4. Polymers in solution
- Introduction to polymers; average molecular weight of a polymer; concentration regimes of polymersolutions; polymer chain conformation; defining factors.
- Solubility of polymers: basic thermodynamic aspects; critical phenomena and phase separation.
- Behavior of polymers in solution and on surfaces; polyelectrolytes and block copolymers.
- Mixed surfactant/polymer systems; models; critical aggregation concentration; rheological aspects.

5. Characterization and industrial/biomedical applications of colloids and soft nanomaterials
-  Overview and comparison of methods for characterization of colloidal systems. Microscopy radiation scattering methods. Calorimetric methods. Spectroscopic methods.
- Technical, industrial and biomedical applications of colloids and interfaces: detergency, emulsification, dispersion and foams; new materials; food colloids; drug delivery systems; model systems for membranes; non-viral gene therapy; biomaterials.

 II - Practical classes

1. Laboratory work: micellization studies of surfactants (or lipids) by conductimetry and surface tension measurement; preparation and characterization of liposomes and liquid crystals; phase diagram studies.
2. Oral presentations (max. 2): topics associated with chapter 5 of the program, developed by groups of students.

Mandatory literature

Jõnsson Bo 070; Surfactants and polymers in aqueous solution. ISBN: 0-471-97422-6
Everett D. H.; Basic principles of colloid science. ISBN: 0-85186-443-0
Hiemenz Paul C.; Principles of colloid and surface chemistry. ISBN: 0-8247-7476-0
Eisenman, George 340; Lipid bilayers and biological membranes. ISBN: 0-8247-6178-2
Shaw Duncan J.; Introduction to colloid and surface chemistry. ISBN: 0-408-71049-7
Hunter Robert J.; Foundations of colloid science. ISBN: 0-19-855188-6
Birdi K. S. 1934-; Lipid and biopolymer monolayers at liquid interfaces. ISBN: 0-306-42870-9

Teaching methods and learning activities

Theoretical classes involve explanation of contents and interactive discussion with students, with use of digital educational media whenever necessary (short films, internet sites, etc). Practical classes comprise laboratory experiments with handing in of lab reports one week after the lab work. The students will also develop a modern a topic on colloids and interfaces throughout the semester, during the practical classes, and will make oral presentations of this topic for the class. The aim of these presentrations is to stimulate team work, autonomous work and communication skills.

Type of evaluation: Distributed assessment with final exam (or tests).

keywords

Natural sciences > Biological sciences > Biological engineering
Physical sciences > Chemistry > Physical chemistry > Surface chemistry
Physical sciences > Physics > Condensed matter properties > Soft matter and polymer physics
Physical sciences > Chemistry > Applied chemistry > Food chemistry
Physical sciences > Chemistry > Biochemistry
Physical sciences > Physics > Biophysics > Molecular biophysics
Physical sciences > Chemistry > Applied chemistry > Pharmaceutical chemistry

Evaluation Type

Distributed evaluation with final exam

Assessment Components

designation	Weight (%)
Prova oral	25,00
Trabalho laboratorial	25,00
Exame	50,00
Total:	100,00

Amount of time allocated to each course unit

designation	Time (hours)
Apresentação/discussão de um trabalho científico	18,00
Estudo autónomo	70,00
Frequência das aulas	56,00
Trabalho escrito	18,00
Total:	162,00

Eligibility for exams

The students must attend a minimum of 3/4 of the number of the practical classes foreseen in the calendar.

Calculation formula of final grade

The final grade of the course, NF, is calculated as follows:
FG = 0.25 x G(LW) + 0.25 x G(OP) + 0.50 x G(E).

G(LW): grade of the lab works, with submission of a simplified report.
G(OP): grade of the oral presentations.

G(E): average grade of G(T1) and G(T2).
- T1, test performed during the semester (if G(T1) ≥ 8.0, the student is exempt from this part in the regular period exam);
- In the regular period exam: part T2 (or T1 + T2, for those who did not take T1 during the semester).
- In the retake exam, the student can take parts T1, T2 or T1 + T2, for approval or improvement.

Approval: cumulatively, G(T1) ≥ 8.0, G(T2) ≥ 8.0, G(TP) ≥ 9.5, G(OP) ≥ 9.5 and FG ≥ 9.5

Classification improvement

Improvement of the grade: by improving component G(E).