P16083: Automated Microfluidic Cell Separator

Systems Design

Table of Contents

Team Vision for System-Level Design Phase

We plan to use our finalized problem statement to construct an in depth functional decomposition of our device, which will drive the thought process behind establishing the concepts to construct each subsystem. By the end of this phase, we will have decided on which concepts to pursue to develop a system level plan for our device that will fit most, if not all, the customer requirements. We will then start the development of these subsystems further.

In this phase we established the functions that the automated cell separator will accomplish. Potential solutions to each of these functions were then generated. Of the list of possible solutions for each function, one specific solution was chosen to construct a device concept. These concepts were compared against each other and to other already existing devices. This phase resulted in the development and validation of a general concept of our system design.

Functional Decomposition

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Morphological Chart and Concept Selection

Morphological Chart

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Concept Generation

Using the morphological chart above, four potential concepts were developed to be compared to each other and the benchmark instrument.

Concepts 1 and 2 are strongly considered models for this project. Concept 3 is a high budget project. And concept 4 has a minimal budget.

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Concept Comparison and Selection

Selection Criteria

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Pugh Chart

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This chart compares each concept to the datum device used in benchmarking, the autoMACS made by Miltenyi Biotec.

Systems Architecture

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Feasibility: Prototyping, Analysis, Simulation

Concept 1

Acquire Cells: Borrow Cells

Culture Cells: Standard Culture

Prepare Cells for Separation: Re-suspend in Buffer

Yeast Growth Curve

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E.coli Growth Curve

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Load Cells into Device: Put in Syringe

Set Voltages and Frequencies: Hardware

Initiate Process: Hardware

Drive Flow: Syringe Pump

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Monitor Flow: Flow Meter

Separate Cells: eDEP

The dielectrophoretic force for a spherical particle is given by:

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Key constraints using planar electrodes: An electric field gradient is only effectively established in sample volumes less than ~30 microns away from the bottom of the device

References: http://onlinelibrary.wiley.com/doi/10.1002/elps.201200242/abstract;jsessionid=F2A6707B83E7EE5CEE779F39BC66341A.f04t04



Modulate Voltages: Operational Amplifier

Run small scale testing with an OP Amp and potentiometer to make sure assumptions of inverting amplifier equations are valid and that the potentiometer will act as expected and that the frequency will not be affected.

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To test if the frequency will be affected small scale testing will be done on a similar Op Amp using function generator to create a signal and then will be analyzed using an oscilloscope.

The Op amp will need to have rails that are high enough to allow the Op amp to amplify the voltages to the upper voltages that are needed. So to check for an available transformer the Ideal Transformer equation will be used to make sure there is a transformer on the market that can achieve the upper rails that are needed.

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The ratio of the transformer that will be needed is 1:8.3. There are commercially available ones that are rated for these voltages.

Modulate Frequency: Micro-controller

Reference: http://www.instructables.com/id/Arduino-Waveform-Generator/

Monitor Signals: Current Monitoring

To monitor the frequency a digital current meter will be used to give a visual representation to the user about of how much current is flowing through the electrodes. The rest of the device will use fuses in areas that are at risk of drawing high current. This will save components from being damaged if there is a current spike and will be easily replaced if such an event occurs.

Display Signals: Digital

Access Separated Cells: 15mL Tube

Analyze Cells: Hemocytometer

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Cost to Run Machine (excluding consumables)

Cost to run is can be checked by calculating finding the potential power use of all components then multiply by the average cost of kW/h ($0.12/kWh the national average).
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Cost to run $0.33 per use.

Experimental Plan

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Instrument Designs

Proposed Device Design

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Proposed Channel Design

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Proposed Electrical Design

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Risk Assessment

The risk assessment chart can be found here.


1. Yafouz, Bashar, Nahrizul Adib Kadri, and Fatimah Ibrahim. "Microarray dot electrodes utilizing dielectrophoresis for cell characterization." Sensors 13.7 (2013): 9029-9046.

2. Gascoyne, Peter “Isolation of Rare Cells from Cell Mixtures by Dielectrophoresis” Electrophoresis. 2009 Apr; 30(8): 1388–1398. doi: 10.1002/elps.200800373


What was done:

Useful to our project:

3. Tai, Chien-Hsuan “Automatic microfluidic platform for cell separation and nucleus” Biomed Microdevices (2007) 9:533–543 DOI 10.1007/s10544-007-9061-7 What was done:

Useful to our project:

Design Review Materials

Plans for next phase

See below for each team members plan for the next phase:

Tyler Lisec

Vincent Serianni

Alexandra LaLonde

Ryan Kinney

Jay Dolas

Chris Molinari


Project Management

Project Photos and Videos

Imagine RIT

Planning & Execution

Problem Definition

Systems Design

Subsystem Design

Preliminary Detailed Design

Detailed Design

Build & Test Prep

Subsystem Build & Test

Integrated System Build & Test

Integrated System Build & Test with Customer Demo

Customer Handoff & Final Project Documentation