Using Advanced Anti-Microbial Material

uic-dmri-logo240x60Some of the students and staff of the College of Engineering University of Illinois at Chicago (www.engineering.uic.edu/) worked with DMRI to design a water filtration system with proper mechanical and purification standards incorporating the DMRI Anti-Microbial material. Continue reading for a summary of their project.


Abstract

goalThe goal of this research is to design a water filtration system with proper mechanical and purification standards incorporating the metallo-organic polymer with anti-microbial properties (DMRI material).

Our final water filtration system has three main units:
1) portable, 2) purification, and 3) storage. Computer modeling and testing with the prototype were conducted to determine effective flow rate and pore size for the filter.

The Escherichia coli (E. Coli) eliminating ability of the DMRI material was determined by running water contaminated with E. coli. through the purification unit. The resulting samples were incubated on nutrient-rich petri dishes for 48 hours. 0% loading of DMRI material showed 44 colonies, but the 2% and 10% loading of DMRI material showed no colony formation. The mechanical and purification standards were met in this study based on World Health Organization (WHO) and benchmark studies.


Introduction

There are current technologies that address water purification, however we are the first to incorporate transportation, filtration, and storage of water directed toward Third World countries. We developed a water purification system that eliminates E. Coli using DMRI material.

water_intro1

Components of Filtration system:
1)Portable bag
2)Purification pipe
3)Storage

water_intro2

DMRI material: polypropylene mixed with anti-microbial additive created with copper, silver, and zinc, which rupture bacteria immediately upon contact.

Escherichia coli: Rod shaped bacteria normally found in lower intestine region. It is commonly used to determine fecal contamination in water samples.


Methods
Movement of E. Coli

water_ecoli1

E-coli are roughly 2 μm in length and therefore a pore size of 2.5 μm to 5.2 μm is ideal to most effectively destroy all bacteria without clogging the filter. In order to obtain this pore diameter a pellet radius of 1.6 mm is chosen by assuming a hexagonal close packing arrangement of the beads in the filter. Based on literature describing the movement of ecoli and Matlab modeling this will be ideal.

Creating the Filtration System:

water_filtration

Module A – portable, un-purified water storage
a)Transport back pack with fill opening and screw cap
b) Stop cock to close during transport.

Module B – purification unit DMRI additive with anti-microbial copper at 10% loading, formed into polymer pellets
c) Quick connect for easy insertion and detachment
d) Filter housing for 1.6 mm antimicrobial pellets

Module C – purified water storage
e) 5 gallon container for filtered water with spigot for clean water access

water_testing240x600Mechanical Testing
Water was flowed through a PVC pipe (5 cm x 16 cm) packed with DMRI material. The volume of the material was varied: 87 cm3, 122 cm3, 162 cm3, and 203 cm3.

E. Coli Dilution Determination
1)10 μL of E. coli was transferred into varying amounts of distilled water: 45 mL, 90 mL, and 135 mL
2)The contaminated water was flowed through a 0% loading DMRI material (324 cm3) packed PVC pipe.
3)The 100 μL of water was transferred into a petri dish contain 20 mL of solid LB agar.
4)The plates were incubated for 48 hours

Purification Testing
1)10 μL of E. coli was transferred into 90 mL of distilled water
2)The contaminated water was flowed through a PVC pipe packed with DMRI material (324 cm3)
3)The 100 μL of water was transferred into a petri dish contain 20 mL of solid LB agar.
4)The plates were incubated for 48 hours

Further Purification Testing
The volume of the DMRI material was also varied. The same technique as the “purification testing” was used.


Results

water_results1-330x200
water_results2-310x260
water_results3-350x250
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water_results4-300x450

Conclusions

Analysis

  • Flow rate is approximately 2.0 L/min
  • 90 mL dilution created approximately 100 colonies, which correlated with Sudan’s water quality (WHO).
  • 2% and 10% loading DMRI material showed no signs of E. coli growth (10 plates of each)
  • ½ filled DMRI material showed no signs of bacteria growth (3 plates each)

Significance

  • 2% and 10% loading DMRI material effectively filters Sudan quality water into potable water, when using E. coli as an indicator

Future

  • Test DMRI material E. coli filtration ability with a cost efficient outlook
  • Test DMRI material for filtration ability of other microrganisms

Acknowledgements
uic-dmri-logo240x60DMRI International: Dan Gamota, Marc Chason, Rick Latella
Advisors: Dr. Greg Jursich, Dr. C Takoudis
Special thanks: Director James Muench, Lab Support Lukasz Zientara, Dr. Terry Layton, and Dr. David Eddington and lab.


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