Principles of Electronic Nanobiosensors
Unit 2: Settling Time
Lecture 2.4: Sensors with Complex Geometry
By Muhammad A. Alam
Professor of Electrical and Computer Engineering Purdue University
alam@purdue.edu
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A fundamental relationship of biosensor
D=1 |
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1<D<2 |
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D=2 |
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3−D |
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Fractal dimension |
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− |
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F |
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Limits of |
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ρ0 |
= Ns ×ts |
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Settling (response) time |
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Minimum number of analyte (depends on transduction) … and the relationship applies even for complex sensors
Alam, Principles of Nanobiosensors, 2013 |
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Array and Network sensors
Complex geometry sensors, numerical analysis difficult .
Alam, Principles of Nanobiosensors, 2013 |
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Recall: Method of diffusion capacitance
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N (t)=C0 ρ0t
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C |
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W |
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C0 |
,1 = |
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2πD |
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log ((W +a0 )/a0 |
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C0 |
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4πD |
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a0−1 −(W +a0 )−1 |
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ρ2
ρ1 |
W (t) = |
2nDt |
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CD(t) = |
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D |
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3 |
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2Dt |
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D(t)= |
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2πD |
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log (( |
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+a0 )/a0 ) |
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4Dt |
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CD(t) = |
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4πD |
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a0−1 −( |
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+a0 )−1 |
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6Dt |
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Alam, Principles of Nanobiosensors, 2013 |
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