Novel Approach to Lactate Sensing Diabetes Pre-screening Tool Christine Zhang, Stephanie Wu, Joseph Sun, Wern Ong, Toby Li

 No Type II Diabetes Pre-screening device exists in the market  To address this need, we will create a hydrogel based lactate sensor where lactate level predicts probability of Diabetes II onset Problem Statement

 Chronic illness characterized by high blood sugar  Type II diabetes is caused by insufficient insulin levels, most often because the body has become resistant to insulin  Insulin is a hormone produced by the pancreas to control blood sugar Diabetes

Indicators/Complications  Heart Disease/Stroke  High Blood Pressure  Blindness  Kidney Disease  Nervous System Disease (Neuropathy)  Amputation  Age  Ethnicity  Weight  Family History  Other Symptoms  Infections  Vision  Slow to heal

 3 pre-diabetes tests  A1C test  Fasting plasma glucose test  Oral glucose tolerance test  Lactate Sensor  Simple  More accessible Current Testing Methods Diabetes Testing A1C Fasting Plasma Glucose (FPG) Oral Glucose Tolerance (OGTT)

 Prevalence  25.8 million people (8.3%) U.S. population  18.8 million people diagnosed  7.0 million people undiagnosed  170 million people worldwide  79 million Pre-diabetes (U.S.)  1.9 million cases of diabetes diagnosed in 2010 (U.S.)  300 million people by year 2025 Diabetes (I & II)

 174 Billion: Total Costs of Diagnosed Diabetes (2007)  116 Billion: Direct Medical Costs  58 Billion: Indirect Costs  Medical expenditure of diabetics 2.3X higher than non-diabetics Market Potential

Performance Criteria  Sense over a large range of lactate levels  0.15 – 0.3 mmol  Work in a timely manner  <24 hrs.  FPG  32 hrs  OGTT  10 hrs  Low cost  < $1 dollar  Glucose Monitors  $10  Roche diagnostics  $190  Accuracy  60%

 Develop lactate sensitive screening device for pre- diabetes screening  Using lactate sensitive hydrogels  Measure volumetric change (directional swelling)  Correlate volume change to saliva lactate Levels  Predict probability of developing type II diabetes Primary Objective

 Tube filled with lactate sensitive hydrogel polymer  Exposure to saliva lactate causes directional swelling of hydrogel polymer  Volumetric change to saliva lactate concentration correlated to blood lactate levels  Correlation of lactate concentration to development of type-2 diabetes Solution Description

Hydrogel Volume Change

Supporting Figures Probability curve

 Hygienic  Non-Invasive  Disposable  Uniform  Cheap < $10  Easy To Use  Accurate Goals

 Polymer Ratio (More DMAEMA = more pH sensitive)  Number of Tubes per batch  Concentration of Lactate Oxidase  [Lactate]  Capillary diameter Factors

System and Environment Lactate Sensor Saliva Sample Lactate Conc. Water pH Proteins Diabetes Prediction Volumetric Change Temperature Lifestyle Change Blood Test See Physician Self Testing Clinical Setting

Literature Research Hydrogel Synthesis Lactate Sensitive Prototype Testing Sensitivity to Lactate Calculation of Calibration Curve Statistics/Analysis Establishment of real world protocols Application Testing Experiment Block Diagram

Performance

Performance (Cont.)

 Hygienic  Non-Invasive  Disposable  Uniform  Cheap $0.23/tube Conclusion

 Hard to measure volume change  Hard to control directional swelling  Hydrogel polymer not very sensitive to small lactate concentrations  Gradual volumetric change not immediate (hrs)  Air bubbles  Un-uniform distribution of lactate oxidase Informal Observations

 Colorimetric Assay – Gradient of color change for more specific lactate readings  Digital Readout – More accurate saliva lactate readings  Testing in a public health application – test viability in large clinical settings (ie. Schools, businesses, clinics) Recommendations

 ng_mnc03.pdf ng_mnc03.pdf References