Microfluidic Bacterial Detection for Resource-Limited Areas

Microfluidic Bacterial Detection for Resource-Limited AreasMallory Williams & Willy LeineweberSanta Clara Micro/Nanosystems Laboratory SCHOOL OF ENGINEERING

1

Outline:Define the problemProposed device solutionHow the device worksResults and progressFuture workScope of impactConclusions and acknowledgements

SCHOOL OF ENGINEERING

http://lightmeetsdark.com/tag/charity-water3.4 million deaths yearly

3Water is supposed to life giving, but What if you risked your life every time you drank water

Global Health Impact of Bacteria-Contaminated Water

10% of global health burden

SCHOOL OF ENGINEERING

Source: WHO

4750 million w/o access to clean water

ASSURED Standard SCHOOL OF ENGINEERINGA AffordableSSensitiveSSpecificUUser FriendlyRRapid & RobustEEquipment FreeDDeliverable to End UsersConventional ElectrochemicalIndicator MethodOur Device

Source: WHO

5REFERENCE Nature? Paul Yager?

Proposed Design

We will now introduce our device design, highlighting how the WHOs ASSURED criteria is implemented in our design, therefore making the device viable in a resource limited setting. 6

Device OverviewSCHOOL OF ENGINEERING

1. Collect sample and load onto device.2. Unfold device to see result3. Take picture to interpret result

Leineweber, W., Williams, M., et al. Towards bacterial pathogen detection using paper-based microfluidic device integrated with a mobile platform. IEEE Healthcare Innovation Point-of-Care Technologies Conference. Seattle, WA. Oct 2014.

7we want to empower the end-user to take charge of their own health care. In a resource-limited area, medical professionals and required diagnostic equipment are scarce. For that reason, we wanted to create a device that an untrained user with no scientific or medical background can use to determine the cleanliness of a given water sample.

To this end, we have created a 3 dimensional microfluidic chip. The field of microfluidics is also commonly called lab on a chip, with the goal of condensing a diagnostic test that would be done manually in a lab into a single chip that ultimately produces an end result. In our case, the device produces a signal where bacteria is present in a water sample.

To meet the User-friendly component of the WHOs ASSURED criteria, we have made a prototype that is incredibly simple to use because the chip is entirely autonomous. The end user will have to gather a small sample of the water source in question, and simply load a small volume into the device to begin the diagnostic test.

We will now discuss how the device is fabricated and the components that make up its 3D structure

ASSURED DevicePaper-Based Microfluidic DetectionCelluloseWax PrintingSCHOOL OF ENGINEERING

8Environmental/Sustainable cellulose, disposable, no harmful chemicalsManufacturability

Device Use

9

Assay DesignSCHOOL OF ENGINEERING

10

Assay Steps

SCHOOL OF ENGINEERINGSteps Involved for DeviceLoad sampleLyse bacterial cellsCapture the targeted bacterial RNAProduce signalAnalyze results

TEM of Streotococcus pyogenes cell lysisSource: Daniel Nelson, UMD

11Ways to lyse cells on paper

Zirconia-coated celluloseImmobilized Capture DNA strandBacterial RNA Target strandDNA/AuNP Detection strandEnhancementNucleic Acid Assay Design

Note how we verified target binding12

Results Binding VerificationFluorescent Imaging of Target Strand

Fluorescent Imaging of Capture Strand

Animation to the left13

Results Assay ResponseSCHOOL OF ENGINEERING

Concentration of Bacterial RNA

Leineweber, W., Williams, M., et al. Towards bacterial pathogen detection using paper-based microfluidic device integrated with a mobile platform. IEEE Healthcare Innovation Point-of-Care Technologies Conference. Seattle, WA. Oct 2014.

14

Results Analysis by Mobile Application

Leineweber, W., Williams, M., et al. Towards bacterial pathogen detection using paper-based microfluidic device integrated with a mobile platform. IEEE Healthcare Innovation Point-of-Care Technologies Conference. Seattle, WA. Oct 2014.

State that we presented result15

Leineweber, W., Williams, M., et al. Towards bacterial pathogen detection using paper-based microfluidic device integrated with a mobile platform. IEEE Healthcare Innovation Point-of-Care Technologies Conference. Seattle, WA. Oct 2014.

Include picture of gradient from slide 1316

v

vvvvv

vvv

vvvvv

v

v

vvv

Load SampleLyse CellBacterial RNA binds with DNA/AuNPCapture PadFuture Directions

Signal Enhancement

Lysis how?17

Potential Impact

Direct effect for developing countries18

Conclusions

Solution detection to low range at low cost ASSURED. Include picture for solution19

AcknowledgementsUniversity Honors Program for awarding us the Hayes Grant

Miller Center for Social Entrepreneurship for awarding us the Roelandts Grant

Dr. Korin Wheeler for her expertise and advice

Dr. Allia Griffin for her valuable input

Our wonderful advisor Dr. Ashley Kim for her continued support and inspiration