Chemical Engineering DEMos & the Medical microDevice Engineering Research Laboratory

1. Chemical Engineering DEMos & the Medical microDevice Engineering Research Laboratory Dr. Adrienne Minerick ITEST High School Enterprise summer teachers' workshop

2. Lab on a Chip Device http://consiliencejournal.readux.org/wp-content/uploads/2008/02/curtis1.png

3. Lab on a Chip Device (2) • Variability in testing • Technician error • False positives / negatives • Point of care test • Device variability • Reproducible and rapid • Operational simplicity Medical Laboratory Future Microdevices Time Minutes Days Cost $$$ $ Sample Volume < Drop Milliliter Reliability Sia et al., 2003, Electrophoresis Tudos et al. 2001, Lab on a Chip Kim et al. 2006, Lab on a Chip

4. Fabrication of Microdevices www.ims.tnw.utwente.nl www.niherst.gov.tt

5. What are students currently interested in? Sports Food Cell Phones Cosmetics Computers Gaming Stations Music Fishing Fashion Environment Scientists & Engineers are the basis for all of these!!

6. Chemical Engineers make the world a better place…. • Civil engineers build bridges, water / sewage conduits • Chemical engineers make the concrete & engineered it to be stronger, less corrosion resistant • Design bioremediation processes for wastewater treatment (now even making biofuels from wastewater) • Mechanical engineers design better engines • Chemical Engineers design synthetic fuels for better performance, life. • Electrical engineers design better computer chips • Chemical engineers do the microfabrication

7. Chemical Engineers even have an impact on health care… • Students in my lab (Medical micro-Device Engineering Research Laboratory) are designing and testing microdevices to analyze blood samples for point of care medical diagnostics.

8. M.D. – ERL Devices Si wafer – “Master” PDMS Channels A B C A B C A B C F D E F D E F D E

9. What is Chemical Engineering? Modern society depends extensively on chemical engineers - they help manage resources, protect the environment, and control health and safety procedures while developing the processes to make products we desire or depend on. Apply chemistry, physics, math, & biology to solve real world issues Raw materials Valuable products

10. Average Annual Earnings for College Graduates and Non-Graduates

11. Engineers / Scientists make more than other majors & they also have a very positive impact on society

12. Timeline $63,000 $30,000 ~75 Death Birth 15 College

13. Chemical Engineering @ Tech Considering graduate school? • Professors hire students in research laboratories • NSF sponsored Research Experience for Undergraduates (REU) Undergraduate Research

14. Contact me at: Adrienne Minerick minerick@mtu.edu

15. Subtopics of Chemical Engineering • Analytical Methods & Products • Biomedical • Biotechnology • Ceramics • Chemical Producers and Suppliers • Databases • Education Resources • Electrochemical • Energy, Conservation and Efficiency • Engineering and Construction • Environment • Fluid Mechanics • Forest Products • Heat Transfer • Law School • Mass Transfer • Materials • Medical field • Nuclear • Particle Technology • Petrochemicals and Fuels • Polymers • Reactions • Process Control • Process Design • Process Modeling • Safety and Hazards • Software Products and Suppliers • Standards • Statistics and Experimental Design • Teaching Topics and Resources • Water Technology

16. Desktop Experiment Modules (DEMo’s) • DEMo’s are versatile, inexpensive, and portable experiments • On student desks throughout a classroom. • Superior to instructor led demonstrations • Each student can closely examine and manipulate the apparatus, • Student teams can progress through experiment discovery at their own learning pace, and • All learning styles are stimulated to maximize understanding of important fundamental concepts.

17. Target Audiences • Introduction to Chemical Engineering Courses • Separations Classes • Analysis Class (data collection, analysis, report writing) • Mass or Heat Transport Classes • Unit Operations • Outreach / Recruiting / Retention • Engage the students • Make concepts come alive • Recruit and retain a broader spectrum of students with new techniques.

18. Seasoned DEMo: Charged up on Electrophoresis - + - + e- Anode Anode Cathode Cathode e- • Electrophoresis is a separation tool for biological species (DNA, RNA, proteins, cells) • Formation of ionic compounds, ionic radii, ionic strength • Electrolysis reactions • pH changes / indicators • Electrophoretic mobility

19. Seasoned DEMo: Brewing with Bioreactors Demonstrate fermentation (microorganisms conversion of food source to product) • Batch vs. Continuous Process • Mass Balances (global) • Reaction vessel • Population life cycle • Reaction of sugar to CO2 • Necessity for separations

20. Desktop Experiment Modules Background (DEMo) • Learning tool that is versatile, fairly inexpensive, and portable such that it can be positioned on student desks • Superior to instructor demonstrations because • each student can closely examine and manipulate the apparatus, • student teams can progress through experiment discovery at their own learning pace, and • all learning styles are stimulated to maximize understanding of important fundamental concepts. • Engage the students to make concepts come alive • Recruiting to engineering & change the paradigm that engineering is impossibly difficult • Diversity in undergraduate programs helps feed diversity in graduate programs. • Can recruit & retain a broader spectrum of students with new techniques.

21. Supplies and Setting Up For each team of 2 students

22. DEMo Equipment is versatile: demonstrates multiple HT mechanisms • One dimensional conduction • Thermal conductivity • One dimensional conduction in composite systems • Thermal contact resistance • Transient heat generation • Steady state heat generation • Heat transfer from extended surfaces (fins) • Convection • Radiation

23. Radiation • This concept is illustrated by the IR thermometers utilized in the experiment. • Use blackbody radiation emitted from objects to determine temperature. • Measure amount of infrared energy emitted by the object • Uses an assumed (constant) emissivity, ε=1

24. Transient Heat Generation • This step is necessary at the beginning of each experiment and can be used to remind students that processes are not always at steady state. Experimental Procedure: • Take initial temperature reading of plate warmer before turned on and record its initial temperature at time 0. • Turn on the plate warmer and begin stop watch at the same time. • At 15-second intervals, take a temperature reading of the plate warmer using the infrared thermometer. Make sure to measure at the same location for each reading. • Continue to take readings until the mug warmer temperature is constant for 45 seconds and reaches steady state.

25. Transient Heat Generation Analysis • Spatial variations not considered so heat diffusion equation is: • Assuming constant generation, q, the solution is: • Using the initial condition that the temperature of the mug warmer was initially at 22.3oC, it is possible to solve for the constant of integration. • Compared to the data collected • Take apart mug warmers the plate is primarily aluminum, which has a density of and a heat capacity of . • Heat generation is Q: Having assumed constant heat generation, why is the data curved? .

26. Steady State Heat Generation: Analysis • Determine by performing an energy balance at the surface Energy generated in the plate = energy convected away from the plate • For relatively still air, measure ambient air Temperature, and thickness of the plate: • Or heat flux is: • Current calculated from information on the mug warmer unit • Obtain electrical resistance (and compare to tabulated values)

27. One Dimensional Conduction • Mug warmer is a heat source on a wall of a material  1D conduction illustrated at student’s desks • Demonstrate thermal conductivity of different materials • Turn on mug warmer with block on top and allow system to heat up for 15 minutes. • Check temperature three times at 30-second intervals to ensure the system has reached steady state. • Note temperature at the surface of the mug warmer may be greater than when exposed only to convection. • Replace with new blocks of material allowing it to equilibrate between temperature readings.

28. 1D Conduction: Analysis • Heat diffusion equation for one dimensional, steady state conduction with constant thermal conductivity is • General solution is: • Boundary conditions determined from student’s experiment. Example uses polycarbonate block 1 cm thick. and • Particular solution in symbolic and numeric form: • Obtain a different temperature profile for each material. • Use Fourier’s Law to determine the conduction heat transfer rate. and • Can use heat flux from SS heat generation experiment too.

29. HT Fins and Convection: Experiment • Heat up plate warmer to reach steady state • Place CPU passive heat sink on the mug warmer and start timer • Measure T at two locations • Repeat with the fan on [data from Christine Lottes and Doug Hall]

30. HT Fins & Convection: Experiment 2 • Heat up plate warmer to reach steady state • Place CPU passive heat sink on the mug warmer and start timer • Record until system reaches SS, turn on fan [data from Rachel Blair and Kaneb Jamison]

31. HT from Fins & Convection: Analysis • Time dependent fin temperature expressions are not covered in undergraduate heat transfer courses. • Ideal to determine T as a function of position not possible with the IR thermometers • System used as an illustrative visual aid when discussing heat transfer from fins • Most CPU heat sink fins are of uniform cross-sectional area. • Tip experiences convective heat transfer (boundary condition) • steady state, position dependent temperature distribution is • Steady state fin heat transfer rate is • where and

32. Diffusion vs. Convective Mass Transfer • Molecular Diffusion: : D=10-7 cm2/s • Diffusional Time Scale: • h=width of channel • Convection • Use Peclet number to compare to diffusion • Estimate Velocity, U • Calculate Pe

33. Human Erythrocytes ABO Typing System: Landsteinner in 1900 [1] 2 main antigens A: N-acetyl-D-galactosamine B: N-acetyl-D-glucosamine O2 7microns CO2 2microns “Red Blood Cells” http://www.academic.marist.edu/~jzmz/HematologyI/Intro8.html • Rhesus Factor: • Presence = positive blood type (Absence = negative) • ~85% of population exhibits Rhesus Factor [2] • ~1.5 million antigens per cell [3] [1] Landsteiner, K. 1900 [2] Dailey. Blood, 1998 [3] Minerick, A.R. AIChE Journal. 2008.

34. Antigen Structure Minerick, AIChE J, 2008

35. Premise- DC Separation of Blood Cells Hypothesized outlet streams Bifurcation point • Foundation • Load an unknown blood sample and identify types based on deflection to the channel • AC-DEP - > 95 % confidence in distinguishing O+ • Hypothesis • DC-DEP - distinguish blood types based on deflection from an insulating obstacle, into a streamline and out to the channels • Impact • Fast, inexpensive, reliable, accurate, and point of care device which could be used in emergency situations, accidents, wars, etc Keshavamurthy et al., 2008, proceedings of NSTI-Nanotech

36. A-: 5 min run @ 0.25 s interval Buffer Conductivity= 50 mS/cm; 10 X magnification

37. Experimental Setup – 1kHz Experiments

38. Time Dependent Rupturing For each image, the fraction of ruptured cells was calculated from raw data showing the amount of cells present in the field of view B+

39. Natural pH Gradients Anode rxn: Cathode rxn: Fused silica used in many applications Silanol groups: O-H dissociation impacts EOF via -potential Charge distribution depends on environment (i.e. pH) Macounova, et al. Anal. Chem. 72 (2000) 3745-3751 Finite number of ions in microchannels allows concentration gradients via mass transfer Minerick, et al. Electrophoresis 24 (2003) 3703-3717

40. Previous Studies - - + + 0.25 0.75 1.25 1.75 2.25 2.75 cm • pH gradients in microchannels can affect transport • Conductivity affects Debye length and EOF • Complicates prediction of system behavior Fluorescence of CI-Nerf along capillary was measured. Intensity increase indicated a pH increase of 4.5 Minerick, et al. Electrophoresis24 (2003) 3703-3717 Reproduced with permission: Minerick, et al. "Development of a pH Gradient in a 20-micron Capillary Microdevice," AES Annual Conference; 2002, Indianapolis, Indiana.

41. Paper microfluidics Fluid flow driven by capillary action of water in paper -no power required Channels can be defined by drawing on paper with wax or a Sharpie marker Lengths of the channel dictate timing of flow into different elements Hundreds of prototypes can be printed at once with a simple printer Urine analysis: Brown indicates glucose, blue indicates protein. Sample is wicked from the base of the tree.

42. ACTIVITY: Hydrolysis Reactions Driven by Electric Fields Lead to pH Changes ANODE (oxidation): CATHODE (reduction):

43. Hydrolysis in paper Experimental procedure: Place a drop of water on strip of pH paper Wipe off excess fluid with paper towel Attach lead to 9V battery Touch the leads on the paper 2 cm apart Observe pH change indicated by color change Remove leads from battery Touch the battery poles on the pH paper Observe pH change indicated by color change

44. COMSOL simulation of pH rise due to OH- generated by hydrolysis in a 2 cm channel. x-axis: Position in channel, y-axis: pH

45. Kaela Leonard Dr. SoumyaSrivastava AytugGencoglu Chung Ja Yang Angela Dapolite Sean Duke Courtney Lentowich Dr. Adrienne Minerick minerick@mtu.edu All work conducted in a certified Biosafety level II (BSL II) laboratory with the approval of Institutional Biosafety Committee (IBC) and Institute Review Board for the protection of human subjects (IRB) www.MDERL.org