Principles of Electronic Nanobiosensors
Unit 1: Introduction to Nanobiosensors
Lecture 1.3: Basic Concepts: Types of Biosensors
By Muhammad A. Alam
Professor of Electrical and Computer Engineering Purdue University
alam@purdue.edu
1
Outline
•Definition of terms continued …
•Types of sensors – mechanism of transduction
•Geometry as a variable for high sensitivity
•Summary and conclusion
Alam, Principles of Nanobiosensors, 2013 |
2 |
Introducing the sensor |
M |
T
T T
Sensor
Capture of molecules on sensor surface
ddtN = kF (N0 − N)ρs −kR N
N(t) = Nss (1−e−(kF ρs +kR )t )
Nss = |
kF ρs |
N0 |
|
kF ρs +kR |
|||
|
|
kF →∞, ρs →0
Alam, Principles of Nanobiosensors, 2013
Nanoscale biosensors: Labeled approach
|
|
DNA Microarray, DNA chip |
Q1 A T |
Q1* |
Imaging |
C G |
|
|
G C
A T
T A
Capture Probe
Optical detection scheme
A Q1 |
A |
Q2 A Q3 |
Q1* G C Q1 |
C Q2 A Q3 |
|||
C |
C |
C |
|
|
|
C |
|
|
|
|
|
||||
G |
G |
G |
T A |
A |
G |
||
C G |
G |
||||||
|
|||||||
|
|
A |
|
||||
A |
A |
T A |
A |
A |
|||
|
|||||||
T |
T |
T |
T |
||||
|
T |
T |
|||||
|
|
||||||
|
|
|
A |
|
|||
|
|
|
|
|
|
||
Alam, Principles of Nanobiosensors, 2013