Product and Process Engineering for Biomedical Applications
Recently, developments in science and technology
call for a wider spectrum of interdisciplinary collaborations in the
engineering field as well as biology and medicine. In the last three years of
our UIC REU program, our undergraduate student researchers have made
contributions to various projects at the cutting edge of biomedical research.
Specifically, we aim at addressing the new need by offering summer undergraduate
research projects from various backgrounds of the REU collaborators from three
different departments in the
A short description of typical interdisciplinary projects and their demands for the planned REU site follows:
Advanced Sensor Technology:
Cerebrospinal fluid (CSF) in the brain has the function of catalyzing neurological reactions, removing metabolites and providing a hydrodynamic protection for the brain against injury. This fluid is stored in the central part of the brain called the ventricles. If the fluid production and re-absorption are unbalanced, fluid accumulates leading to enlarged ventricles. This condition is known as hydrocephalus. Hydrocephalus can cause severe damage or if untreated leads to death. Current treatment based on fluid removal by static “shunt” valves has a high failure rate and requires painful and expensive revisions.1-3 We wish to improve the existing treatment by using a smart wireless sensor together with a feedback controller.
The goal of the REU projects is to develop and test a sensor for accurately measuring the fluid volume in the ventricular space of the human brain. The mechanism has already been applied successfully by one of our last year’s REU students (Joel Stanfield – A Volume Sensor Based on Impedance, REU student Summer 2004). This sensor exploits electrolytic and piezoelectric effects for accurately measuring fluid levels in closed body cavities. The sensor has to be biocompatible and easy to construct.
Control of Biological Functions:
The data from the sensor will be transferred to a feedback controller. The purpose of the feedback loop is to maintain the CSF amount at desired levels and prevent the dangerous intracranial pressure elevations. The controller dynamics will be based on a dynamic flow model of the CSF. The system model includes momentum and mass balances of the CSF in dynamic fluid-structure interaction with the elastic brain tissue. The controller will activate a biocompatible actuator, i.e. an electromagnetic micro pump. The micro pump will be developed specifically to pump CSF. It will actively pump fluid when an alternating current is applied, but remain closed otherwise.4-5
A micro telemetry sensor inside the brain will also
be able to transfer data about the condition of the brain to the main control
unit outside of the cranium. The sensor and the antenna coils act as an
inductor/capacitor circuit and are positioned close enough that there is
magnetic coupling between the two devices. These readings are concerning vital
parameters of the CSF as the pressure and volume of the fluid into the brain.
The proposed wireless device is already of great interest in the neurosurgical
field thinking of the collaboration already ruling with the Department of
Starting in the late 1980s,6 miniaturized fluid pumping systems have been used in many areas such as medicine, office automation, chemical analysis and industrial process control. Micropumps can be separated into two major categories: with or without moving components. Micropumps with moving components can be further classified into two subcategories based on the actuating mechanism: reciprocating and peristaltic.7 Actuators commonly use the effect of piezoelectricity,8 electrostaticity,9-10 thermopneumaticity,11 or electromagnetism.12 For the micropump without moving parts, electrohydrodynamic,13 electroosmotic,14 and ultrasonic effects15 are utilized. The control of fluid inside the pump can be realized either by valves or without valves (valveless).
In the proposed project, the design and development of a micropump biocompatible with the human body will be investigated. The selection of actuation modes and actuation valves will be done with the following design considerations:
· Biocompatible outer surface,
· Small dimensions for minimal disturbance to the human body,
· Long-term durability.
The entire system will be miniaturized to put on a space smaller than 25 mm3.
1. Czosnyka, Z, M Czosnyka, H.K. Richards and J.D. Pickard, Laboratory Testing of Hydrocephalus Shunts” Acta Neurochir., 144: 525, 2002.
2. Linninger, A. A., C. Tsakiris, and R. Penn, "A Systems Approach to Hydrocephalus in Humans”, Proc. of the Seventeenth Meeting of Cybernetics and Systems Research (EMCSR 2004), ISBN 3852061695, pp231, Vienna, Austria, April 13-16, 2004.
3. H. J. Yoon, J. M. Jung, J. S. Jeong, S. S. Yang, Micro devices for a cerebrospinal fluid (CSF) shunt system, Sensors and Actuators A, 110 (2004) 68.
4. D. Greitz, “Cerebrospinal fluid circulation and associated intracranial dynamics. A radiologic investigation using MR imaging and radionuclide cisternography”, Acta Radiol. Suppl, vol. 386, pp. 1, 1993.
5. Linninger, A. A., Tsakiris, C., Munoz, A., Lee, M. and Penn, R., “Hydrodynamics of the Cerebrospinal Fluid Flow in the Human Brain“, Paper 462g, AIChE Annual Meeting, Nov. 16 – Nov. 21, San Francisco, CA, 2003.
6. J. G. Smits, “Piezoelectric micropump with three valves working peristatically”, Sensors & Actuators, vol. A21-A23, pp. 203-206, 1990
7. S. Shoji and M. Esashi, “Microflow devices and systems”, J. Micromech. Microeng. 4, 157-171 (1994)
8. H. T. V. Van Lintel, F. C. M. van de Pol and A. Bouwstra, “Piezoelectric mircropump based on micromachining of silicon”, Sensors and Actuators 20 153-67 (1988)
9. R. Zengerle, J. Ulrich, S. Kluge, M. Richter, A. Richter, “A bidirectional silicon micropump”, Sensors and Actuators A 50, 81-86(1995)
10. S. Zappe, M. Baltzer, Th. Kraus and E. Obermeier, “Electrostatically driven linear micro-actuators: FE analysis and fabrication”, J. Micromech. Microeng., Vol. 7, No. 3, 204-209 (1997)
11. M. Elwenspock, T S J Lammerink, R. Miyake and J H J Fluitman, “Towards integrated microliquid handling systems”, J. Micromech. Microeng., Vol. 4, No. 4, 227-245(1994)
12. A. Feustel, O. Krusemark, J. Muller, “Numerical simulation and optimization of planar electromagnetic actuators”, Sensors and Actuators A 70, 276-282(1998)
13. G. Fuhr, R. Hagedorn, T Muller, W. Benecke and B. Wagner, “Pumping of water solution in microfabricated electrohydrodynamic systems”, Proc. IEEE-MEMS Workshop, pp25-9 (1992)
14. D. J. Harrison, K. Seller, A. Manz and Z. Fan, “Chemicalanalysis and electrophoresis systems integrated on glass and silicon chips”, Digest of IEEE Solid-State sensor and Actuator Workshop pp110-3 (1992)
15. S. Miyazaki, T. Kawai and M. Araragi, “A piezo-electric pump driven by a flexural progressive wave”, Proc. IEEE-MEMS Workshop, pp283-8(1991)