2010 IEEE EMBS Conference on Biomedical Engineering & Sciences (IECBES 2010), Kuala Lumpur, Malaysia, 30th November - 2nd December 2010. Analysis and Experiment of Centrifugal Force for Microluidic ELISA CD Platform Fatimah Ibrahim Dept. of Biomedical Engineering, Faculty of Engineering,University of Malaya, Kuala Lumpur, Malaysia fatimah@um.edu.my Peyman lahanshahi Dept. of Electrical Engineering, Faculty of Engineering,University of Malaya, Kuala Lumpur, Malaysia Noorsaadah Abd Rahman Dept. of Chemistry, Faculty of Science,University of Malaya, Kuala Lumpur, Malaysia Maria Kahar Bador Abdul Kahar Dept. of Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia Marc Madou Dept. of Mechanical, Aerospace and Biomedical Engineering, University of California Irvine, CA,USA Abstract- This pape.' p.'esents an analysis and experiment of centrifugal force Ol' microluidic Enzyme-Linked Immunosorbent Assay (ELISA) on a compact-disc (CD) platfOl'm, The ELISA CD was designed based on the centrifugal fo.'ce as a d"iving force while capilla.'y Ol'ce acts as preventing barrier, The CD composed of 2 layers: the substrate laye.' is made ofPMMA and the top layer is laminated with an Adhesive Sealing Films (ASF) 0' thermal seal. The PMMA substrate was fabricated by CNC micromachining, The ELISA CD consists of7 .'ese.Voirs: waste, detection, serum, conj ugate, washing solution, substrate and stopping solution, In the expe"iment, the reservoilS were illed with colour liquid and the luid low behaviour of the liquid in the CD was studied and monito.'ed by a customized CD spin stand system equipped with visualization system, The experimental test results show an average of 9% e.TO.' when compa.'ed with the theoretical calculation of bu.'st f.'equency for all the reservoilS, Keywords- Mi"oluidics, centl'ifugal Ol'ce, Lab on CD, microsystem, ELISA, Burst frequency I. INTODUCTION Anderson was the irst person who developed the centrifugal luidic system in 1969 and in many years this centrifugal microluidics has been studied by many researchers[1-5] Centrifugal microluidic system which is also known as Lab on-a-compact disc (CD), has been commercialized for clinical Ali A, Nozari Dept. of Mechanical Engineering, Faculty of Engineering,University of Malaya, Kuala Lumpur, Malaysia Norhayati Soin Dept. of Electrical Engineering, Faculty of Engineering,University of Malaya, Kuala Lumpur, Malaysia Siti Zawiah Md Dawal Dept. of Eng, Design and Manufacture, Faculty of Engineering,University of Malaya, Kuala Lumpur, Malaysia Kameel Abi Samra Dept. of Mechanical, Aerospace and Biomedical Engineering, University of Califonia Irvine, CA,USA biochemistry for blood diagnostics and rapid immunoassays by companies Abaxis and Gyros, respectively [I]. Although components of microluidic system: micropump, microvalve, microchannel, siphon, mixer, chamber and metering part are still under individual studies, in more advanced level, the integrated microluidic system in diferent application is the topic of investigation for improving conventional bulky systems with low eficiency. Amongst all the most popular propulsion mechanisms (such as pneumatic, hydraulic, electrokinetic, thermal, acoustic, electrohydrodynamic, magnetic, chemical and electrochemical pump), centrifugal pumping beneits from being simple and inexpensive. Besides, centrifuge system is not dependent on pH, sample electrical, magnetic and ionic properties and luid contact. Centrifugal microluidic platform has been extensively studied in biology and chemistry because of versatility in manipulation of luid, compatibility with wide range of sample, simple centrifugal pumping drive, and low fabrication expenses [2], To control the liquid low, microvalve plays the main role in the system. The accuracy of the result for the microluidic system depends on it strongly. The valves are divided into two categories: active and passive valves. Passive valves, such as capillary valves, do not require any moving parts or external stimuli since their operation is dependent on the exploitation of generated surface tensions in the micro-domain. On the other hand, active valves (such as thermally actuated gels, 978-1-4244-7600-8/10/$26.00 ©2010 IEEE 466