Enzyme Biosensor Detection of glycerides in biodiesel Team
Enzyme Biosensor Detection of glycerides in biodiesel Team Members: Ben Wilson Matt Yourek Megan Templeton Mentor: Dr. Tom Hess Client: Dr. Dev Shrestha 1
Opportunity Statement � Design, fabricate, and test a handheld biosensor that uses a modified p. H meter combined with an immobilized enzyme electrode to detect the amount of free and total glycerol in a sample of biodiesel. 2
Current Industry Standard � Currently biodiesel makers use a gas chromatograph to measure the amount of glycerol within their biodiesel. While the GC provides a very accurate measurement, it is a time consuming process to prepare and test a sample. 3
Similar Products Blood glucose meters � Blood pressure sensors � i-Spec Q-100 - uses impedance spectroscopy technology, which is similar to infrared spectroscopy � 4
Client Needs Small � Light � Fast response time � Simple to use � Accurate � Easy to calibrate � Reusable � Strong/Durable � Inexpensive � Sensitive to small changes in p. H � User friendly � 5
Technical Specifications � � � � � Dimensions ≤ 8”x 6”x 5” Weight of about 2 lbs Response time of 10 minutes or less Able to test four samples in one hour Error margin of 5% of concentration measurement Can withstand repeated drops from 5 ft Does not bend or flex Storage for electrode Result is automatically displayed in large numbers Total of five buttons or less Visual or audio signal when measurement is complete Audio signal on button push Large buttons that take < 3. 5 lbf to push Matte/textured finish for added grip Battery operated Takes user < 5 minutes to change electrode Automatic zeroing upon button push Visual or audio signal for low battery One electrode can be used up to 50 times Costs less than $300 to fabricate 6
Instrument Design 1 Pros: � Very similar to p. H meter � Easy to store membrane Cons: � Higher chance of damage to electrode � Could experience bad connection between electrode and instrument 7
Instrument Design 1 8
Instrumental Design 1 9
Instrument Design 2 Pros: � Simple to use � Doesn’t need to be held Cons: � Would need to be more durable/sealed � More complicated to wash and store membrane 10
Possible Membranes Gelatin-Lipase membrane - cited in literature research paper � PVA membrane - found during membrane research � PVDF membrane - found during membrane research � 11
Membrane Design 1 Gelatin-Lipase Membrane Pros: � Easy to make � Similar testing published in papers Cons: � Published paper does not include all information � Membrane falls apart in storage buffer and water � Does not give reliable m. V readings 12
Membrane Design 2 PVA Membrane Pros: � Mechanically strong and flexible � Resistant to oil and solvent � Has ionic conductivity that allows easy flow of electrons � Used in a biosensor to detect glycerides Cons: � Complex process to create membrane � Water-soluble, so it might dissolve during reaction 13
Membrane Design 3 PVDF Membrane Pros: � Resistant to acids, bases, and solvents � Mechanically strong � Low cost Cons: � Requires very advanced equipment/techniques � A detailed process to create � Used for the growth of neurons, not typically used with a biosensor 14
Experimental Data � Tested both pure canola oil and a biodiesel sample using the gelatin-lipase membrane � The following graphs are the results of millivolt change during the testing process 15
Experimental Data � Pure canola oil sample Peak to peak average = 22 m. V 16
Experimental Data � Biodiesel 30 minute sample (Part 1) Peak to peak average = 18 m. V 17
Experimental Data � Biodiesel 30 minute sample (Part 2) Peak to peak average = 18 m. V 18
Experimental Data � Using the estimated peak to peak value for each test, as well as the glyceride percent concentration we can obtain the following two point calibration 19
Microcontroller Option 1 Arduino UNO with ATmega 328 Pros: � Easy to use/program � Comes in design kits � Lots of memory � LCD screen comes with wiring instructions for Arduino Cons: � New programming language to learn � Minimum voltage input of 6 V � Slower clock rate � Problems could be made worse by mass of online information 20
Microcontroller Option 2 PICAXE 14 M 2 Pros: � Familiar programming language � Faster clock rate � Dr. Wolbrecht teaches a class that uses them Cons: � Manufactured and distributed from UK � Not much programming help/information � Less memory 21
Design Suggestions Instrument - Design 1, external electrode design � Membrane - N/A � Microcontroller - Option 1, Arduino UNO with ATmega 328 � LCD screen - hacktronics LCD screen, comes with Arduino wiring � Housing material - ABS 3 D printed plastic � 22
Further Experimentation � Creation and testing of PVA and PVDF membranes � Effect of multiple layers of cellulose acetate solution on reaction time and membrane preservation � Relation of m. V amplitude to concentration percent 23
Detailed Schedule Nov 30 – Dec 9: Testing of gelatin-lipase membrane � Dec 2: Snapshot � Dec 6: Design review � Christmas Break � Jan 17 – Jan 25: Testing of PVA membrane � Jan 26 – Feb 7: Testing of PVDF membrane � Feb 8 – Feb 24: Finishing touches on design and ordering of any parts � Feb 27 – Mar 9: Fabrication � Spring Break � Mar 19 – Apr 26: Validation � Apr 27: Engineering Expo � 24
Budget Materials for Membranes: $561 � Misc. Chemicals: $500 � Microcontroller: $90 � LCD Screen: $11 � Misc. Electronics: $50 � Housing: $300 � � Total: $1512 25
Questions? � Ben Wilson – Mechanical Enginner � Matt Yourek – Biological and Agricultural Engineer � Megan Templeton – Biological and Agricultural Engineer 26
- Slides: 26