Abstract Introduction Method Results: Challenges Ahead Conclusions ...
Graduate Category: Engineering and Technology Degree Level: PhD Abstract ID#: 1195
A Portable Device on Water Pollution Evaluation 1 Sun ,
Jianfeng 1
Ran
1 Ran ,
Derek
1 Tran ,
1 Wan ,
Kaitak
Sinan
2 Muftu
3 Gu
April
Nano and Micro Biomechanical Characterization and Testing Lab, Northeastern University, Boston, MA, 02115 2 Applied Biomechanics and Tribology Laboratory, Northeastern University, Boston, MA, 02115 3 Civil and Environmental Engineering Department, Northeastern University, Boston, MA 02115
Results: Image Processing and Filtration Percentage Strain H
100% filtration
Filtration Percentage
100%
20um
Strain Q 20um
Strain H
60% 80% 40%
Strain Q
0% 80% 40%
Strain A
Strain A
0%
20um
0
0.05
0.1
0.15
Flow Velocity, cm/s • • • •
• People in developing areas are suffering water pollution everyday. One of the most concerning problems is bacterial contamination in underground water1. • What make this even worse is the research on this problem is very limited due to the lack of facilities and experience researchers. • In this study we are making a portable device on bacterial filtration percentage: • Could be used either in the lab or on site • Easy to use for people with low educational level • Low cost
Introduction • Filtration Percentage: # of bacteria trapped in the filter Total # of bacterial flow into the filter • Disadvantages of Traditional Method (column test): • Time consuming (hours ~ days) • High cost of experimental set up • Usually conduct in the lab • Result can not be derived directly • Therefore we designed a new micro-channel test: • Decreased the column size to micron scale • Simply to set up • Very time efficient (1~10mins) • Result obtained more directly • Results are highly correlated to result of old method
Compare results from two methods • Traditional test: • Flow velocity: 0.015cm/s • Ionic concentration: 3mM
100% filtration 95%
Microfluidic Test a
Abstract
Strain H has highest filtration percentage among the three strains. Filtration percentage is almost 100% Filtration percentage of all three bacterial strains are negatively correlated to the flow velocity At low flow velocity, filtration percentage of strain H overcome 100%. This is because the bacteria from upper stream are flushed in the focus region
0.0015cm/s
75%
Q
H 0.015cm/s
A K 55%
• Microfluidic Test: • Flow velocity: 0.0015~0.15cm/s • Ionic concentration: 3mM
35%
• Result of micro-channel method is linearly correlated to the result of traditional method
15%
• Low flow velocity indicates higher filtration percentage for all strains
0.15cm/s
15%
35%
55%
75%
Traditional Filtration Test a
95%
Challenges Ahead 1. Microscope on a phone
2. Integrate micro pump with micro-channel
Method Inlet
Bacterial solution
Syringe pump
Conclusions
PC Droplet lens turns smart phones into microscopes2
•
This new micro-channel method are suitable for: • Using on site and derive the result directly • People with no research background to use • Researchers use in the lab more time efficiently and economically
•
This new micro-channel method are NOT suitable for: • Looking into the filtration due to clogging • This new micro-channel method is validated by comparing it’s result with the traditional method
•
This new method shows a great potential to replace the traditional method
Microscope
Acknowledgement
Image Process Micro Pump Smart Phone
Procedures: 1. 2. 3. 4. 5. 6.
Fill the channel with Potassium Chloride background solution Inject bacterial solution and let it settle on the glass surface for 10 mins Pump in the KCl solution at low flow velocity Increase flow velocity until no more bacteria are detached Snapshots were taken in a certain time step Process the image and counting the number of bacteria with Matlab code
This work is supported by National Science Foundation CMMI # 0757140
References
1. W.H.O. 2008 annual report in 2008 2. Steve Lee, “Droplet lens turns smart phones into microscopes” , 2005 •
The new method provide a potential to make a portable device in water pollution evaluation
A Portable Device on Water Pollution Evaluation 1 Sun ,
Jianfeng 1
Ran
1 Ran ,
Derek
1 Tran ,
1 Wan ,
Kaitak
Sinan
2 Muftu
3 Gu
April
Nano and Micro Biomechanical Characterization and Testing Lab, Northeastern University, Boston, MA, 02115 2 Applied Biomechanics and Tribology Laboratory, Northeastern University, Boston, MA, 02115 3 Civil and Environmental Engineering Department, Northeastern University, Boston, MA 02115
Results: Image Processing and Filtration Percentage Strain H
100% filtration
Filtration Percentage
100%
20um
Strain Q 20um
Strain H
60% 80% 40%
Strain Q
0% 80% 40%
Strain A
Strain A
0%
20um
0
0.05
0.1
0.15
Flow Velocity, cm/s • • • •
• People in developing areas are suffering water pollution everyday. One of the most concerning problems is bacterial contamination in underground water1. • What make this even worse is the research on this problem is very limited due to the lack of facilities and experience researchers. • In this study we are making a portable device on bacterial filtration percentage: • Could be used either in the lab or on site • Easy to use for people with low educational level • Low cost
Introduction • Filtration Percentage: # of bacteria trapped in the filter Total # of bacterial flow into the filter • Disadvantages of Traditional Method (column test): • Time consuming (hours ~ days) • High cost of experimental set up • Usually conduct in the lab • Result can not be derived directly • Therefore we designed a new micro-channel test: • Decreased the column size to micron scale • Simply to set up • Very time efficient (1~10mins) • Result obtained more directly • Results are highly correlated to result of old method
Compare results from two methods • Traditional test: • Flow velocity: 0.015cm/s • Ionic concentration: 3mM
100% filtration 95%
Microfluidic Test a
Abstract
Strain H has highest filtration percentage among the three strains. Filtration percentage is almost 100% Filtration percentage of all three bacterial strains are negatively correlated to the flow velocity At low flow velocity, filtration percentage of strain H overcome 100%. This is because the bacteria from upper stream are flushed in the focus region
0.0015cm/s
75%
Q
H 0.015cm/s
A K 55%
• Microfluidic Test: • Flow velocity: 0.0015~0.15cm/s • Ionic concentration: 3mM
35%
• Result of micro-channel method is linearly correlated to the result of traditional method
15%
• Low flow velocity indicates higher filtration percentage for all strains
0.15cm/s
15%
35%
55%
75%
Traditional Filtration Test a
95%
Challenges Ahead 1. Microscope on a phone
2. Integrate micro pump with micro-channel
Method Inlet
Bacterial solution
Syringe pump
Conclusions
PC Droplet lens turns smart phones into microscopes2
•
This new micro-channel method are suitable for: • Using on site and derive the result directly • People with no research background to use • Researchers use in the lab more time efficiently and economically
•
This new micro-channel method are NOT suitable for: • Looking into the filtration due to clogging • This new micro-channel method is validated by comparing it’s result with the traditional method
•
This new method shows a great potential to replace the traditional method
Microscope
Acknowledgement
Image Process Micro Pump Smart Phone
Procedures: 1. 2. 3. 4. 5. 6.
Fill the channel with Potassium Chloride background solution Inject bacterial solution and let it settle on the glass surface for 10 mins Pump in the KCl solution at low flow velocity Increase flow velocity until no more bacteria are detached Snapshots were taken in a certain time step Process the image and counting the number of bacteria with Matlab code
This work is supported by National Science Foundation CMMI # 0757140
References
1. W.H.O. 2008 annual report in 2008 2. Steve Lee, “Droplet lens turns smart phones into microscopes” , 2005 •
The new method provide a potential to make a portable device in water pollution evaluation
