Introduction to Biosensors. Prof. Xingwei Wang

Transcription

1 Introduction to Biosensors Prof. Xingwei Wang 1

2 Brain Storm What do you think of biosensor? 2

3 Brain Storm What do you think of biosensor? 3

4 Significance & Great Demands Civil defense Food safety Criminology Environmental Monitoring Public Health Pathology 4

5 Brief History 1956, Prof. Clark, Father of biosensor concept, Invention of the oxygen electrode 1962, First description of a biosensor 1972/5, First commercial biosensor: Yellow Springs Instruments glucose g biosensor 1975, First immunosensor 1980, First fibre optic ph sensor for in vivo blood gases 1983, First surface plasmon resonance (SPR) immunosensor 1987, Launch of the MediSense ExacTech blood glucose biosensor 1990, Launch of the Pharmacia BIACore SPR-based biosensor system 1992, i-stat i launches hand-held held blood analyser 1996, Abbott acquires MediSense for $867 million 1998, Launch of LifeScan FastTake blood glucose biosensor 1998, Merger of Roche and Boehringer Mannheim to form Roche Diagnostics 2001, LifeScan purchases Inverness Medical's glucose testing business for $1.3billion 5

6 What is a Biosensor A device that uses biological components e.g. enzymes to indicate the amount of a biomaterial Trace biomaterial? Quantitative results? Unnecessary (Eg. Metal ion, etc.) Unnecessary (Eg., Pregnancy test) 6

7 Components Bio Recognition Element Transducer Signal Output Requires: Sample Immobilization Enzymes; Antibodies; Receptors; Whole cells... Electrochemical Optical Requires: Simple read out and data interpretation; Easy to use; Quick response. 7

8 Performance Factors Sensitivity: Concentration; weight Specificity/Selectivity: discriminate between substrates Speed: Bench->Chip >Chip->Real >Real Time Accuracy: False signal Cost Easy to use Life time 8

9 Biosensing for Macromolecules Steps: Immobilization Mixing Washing the non-specific bindings Signal transduction Markers: Enzymes Fluorescence tags Radioactive tags Molecular: Waston-Crick Base pairing Antibody-Antigen Antigen binding 9

10 Immunosensor Antibody can be against Bacteria Complex carbohydrates Smaller organic molecules 10

11 DNA Complementary Chains A Four nitrogen bases Complementary chains T G C C A G T 11

12 Six Steps 1) Select the single-stranded stranded capture DNA sequence 2) Attach the capture DNA strand to a probe 3) Introduce the samples to be identified to the probes 4) Hybridization will occur if the sample is complementary with the capture sequence on the probe 5) Wash away the remaining unattached samples 6) Judgment 12

13 Transducer Electrochemical (Potentiometric, Voltammetric, Amperometry, Conductimetric) Optical (Fluorescence, Absorbance, Light scattering, Refractive index) Mechanical, Thermal, Piezoelectric, Magnetic 13

14 Glucose Sensor 14

15 Microcantilevers From 15

16 Medical Telesensor An array of chips to monitor body functions Wireless transmission Military: Locate wounded soldiers Domestic: Intensive patients From 16

17 Miniaturization Infrared microspectrometer Size of a sugar cube From 17

18 Broad Potential Applications Warfighter Physiological Status Monitoring (WPSM): remote triage of injured Soldiers Heart rate, breaths taken, skin temperature and ballistic impact Foster-Miller (Waltham, Mass.) Putting these sensors on a belt that's sewn into a shirt (Picture from 18

19 Benefits Academia Biosensor Industry Military 19

20 Challenges and Trend Cost Sensitivity Selectivity Speed Small? Ease to use? Cheap Sensitive Selective Speed Portable Simple Integrated Mass produced Multiple analytes 20

21 Multidisciplinary Nature Optics Market Biology Electronics Biosensor Chemistry Instrumentation Physics 21

22 Worldwide Biosensor Vendor Market,

23 References (Reading List 1) sens.htm m m Sensors in Biomedical applications - fundamentals, technology and applications, by Gabor Harsanyi, ISBN: , CRC Press;

24 Education Who I am? MS, Ph.D., Electrical Engineering Virginia Tech Certificate, Future Professoriate Virginia Tech Contact Office Hours: Wednesday 3:30 am 5:30 pm; or, make an appointment Phone: Office: BL 421A Xingwei_Wang@uml.edu 24

25 Syllabus tm The account name: Class_Wang Password: Circuit34567 Literature Review Report Presentation 25

26 Grading Policy Attendance 10% Presentation I 10% Report I 10% Presentation II 10% Report II 10% Final Presentation 25% Final Report/Project 25% Total 100% 26

27 Project topics 1. Ultrahigh sensitive biosensors 2. Fast response biosensors 3. In-vivo blood pressure sensor (St. Jude Medical) 4. Intravascular ultrasound imaging (IVUS) (Volcano) 5. Biosensor integration/miniaturization 6. Optical coherence tomography (OCT) 7. Glucose sensor 8. Nano-Biosensor 27

28 Class Schedule Tentative. Please check frequently for updates. Lecture topics do NOT necessarily follow the order of the schedule. Topic contents may need more or less time than what is allocated. 28

29 About You You are? 29