Exam Microsystems and nanotechnologies

Question 1

Top-down micro and nano fabrication technologies involve several sequential cycles of what unit operations?

Answer 1

Unit operations:

1. Deposition
2. Lithorgaphy
3. Etching

Question 2

What are MEMS?

Answer 2

MEMS are microelectromechanical systems

Question 3

Why is MEMS important and needed?

Answer 3

The MEMS add mechanical functionalities to micro fabricated devices

Question 4

Name one important difference in microfluidics compared to fluid in macro scale!

Answer 4

1. In microfluidics we have large surface-to-valume ratios

2. In microfluidics we have laminar flow

Question 5

Name some potential disadvantages of Lab-on-chip systems for bio sensing with respect to standard laboratory procedures

Answer 5

One potential disadvantage is the difficulty to mix different reactant fluids

Question 6

Name one application involving the use of top-down microfabricated devices in neuroengineering

Answer 6

Microelectrode arrays

Question 7

Name some standard multi electrode array neural probes (MEA)!

Answer 7

1. Utah probes

2. Michigan probes

Question 8

Name some facts about MEA (Multielectrode arrays)!

Answer 8

1. MEAs can reach up to 1000 recording sites in an area of the order of 1cm2
2. the MEAs can stimulate fibers at different depths of the neural tissues
3. MEA can be used both for recording and stimulation

Question 9

Name one application and some characteristics for the Microfluidic lab-on-chip device!

Answer 9

1. The lab-on-chip device can function as platforms for neuron culture and manipulation
2. Microfluidic lab-on-chip can integrate micro electrodes for electrophysiology studies of single neurons
3. Microfluidic lab-on-chip can allow co-culture of different types of neural cells and other cells
4. Microfluidic lab-on-chip can allow spatially controlled growth of neuritis
5. Microfluidic lab-on-chip CAN’T be integrated with brainslices from test animals

Question 10

What is the main motivation for the use of lab-on-chips to function as platforms for neuron culture and manipulation?

Answer 10

The main motivation is the ability to control the microenvironment surrounding neuronal cells

Question 11

What particle size should the nanoparticle be for a long lifetime and be able to reach their destination (the brain)?

Answer 11

The particle size should be of the order of 50 nm

Question 12

In what scale is top-down micro and nanofabriation pattern materials in?

Answer 12

20 nm

Question 13

Name some advantages of Lab-on-chip systems with respect to standard laboratory procedures!

Answer 13

1. portability

Question 14

What device is cell cultures performed in microfluidic chips?

Answer 14

Cell-chips

Question 15

Name some unique capabilities of cell-chips!

Answer 15

1. precise control of cellular microenvironment
2. ability to integrate on-chip techniques for analysis if biochemical reactions in cell
3. ability to fractionate heterogenous cell populations
4. you CAN’T produce large number of cells

Question 16

Name one application involving bottom-up technology in neuroengineering!

Answer 16

nanoparticles for drug delivery across the blood-brain barrier

Question 17

Name the main advantage with multi electrode arrays (MEA) with respect to conventional single electrodes ot tetrodes!

Answer 17

1. Multielectrode arrays provide large number of electrodes separated by small distances

Question 18

Why has nanotheranostics been considered for therapy of brain diseases?

Answer 18

Nanoparticles can be functionalized to cross the blood brain barrier and assist image-guided therapy