Innovative Sensors Flashcards
What is the nanometer scale?
- From a few atons to many molecules
- Reducing material sizes: increasing the available surface area
Nanotechnology studies materials with sizes of roughly 1 - 100 nm.
What is the definition of nanotechnology?
The understanding and control of matter at dimensions of roughly 1 to 100 nanometers, where unique phenomena enable novel applications.
Nanoscale materials often have chemical, physical, or biological properties that are different from those of their larger counterparts.
True or False?
True.
Such differences may include altered magnetic properties, altered electrical
or optical activity, increased structural integrity, or altered chemical or
biological activity.
Nanoscale materials have chemical, physical, or biological properties that are the same as those of their larger counterparts.
True or False?
False.
Nanoscale materials often have chemical, physical, or biological properties that are different from those of their larger counterparts.
Such differences may include altered magnetic properties, altered electrical
or optical activity, increased structural integrity, or altered chemical or
biological activity.
What is ‘top-down’ production of nanomaterials?
- Physically machining materials to nanometer size by grinding, milling, etching, or lithography.
- A smaller size means a bigger surface area, resulted in improved water absorption, flavor release, bioavailability, faster rates of catalysis.
What is ‘bottom-up’ assembly of nanomaterials?
Self-assembled
Describe the bottom-up approach: self-assembly.
Self-assembled polymers
- Form self-assembled ordered nanostructures
Emulsions
- Thermodynamically unstable dispersions of two or more immiscible liquids forming an o/w or w/o emulsion.
- Nanoemulsions with droplets of 50-1000 nm in diameter.
List types of inorganic nanoparticles in foods. [6]
Bonus: Describe the products they are used in and their function.
List organic nanoparticles. [3]
Bonus: Describe the products they are used in and their function.
Describe food nanotechnology from farm to table.
What are the benefits of nanotechnology-based sensors? [6]
- Offer many advantages over the conventional detection methods such as HPLC, NIR, or specific enzymatic methods that are time consuming and expensive.
- Rapid, high-throughput detection, simple, fast, cost effective; reduced power requirements; easier recycling
- Multi-walled carbon nanotube-based biosensor, 10^-15 microorganisms
Describe the use of a confocal Raman for monitoring pesticide behaviours.
Describe use of SERS mapping to detect chemical food contamination.
Describe the pesticide penetration process.
- Cannot be fully removed by washing after irreversible penetration.
What is a possible solution?
Not SERS mapping.
