Cyclic Olefin Copolymer Microfluidic Devices for Forensic Applications

Abstract

Microfluidic devices offer important benefits for forensic applications, in particular for fast tests at a crime scene. A large portion of forensic applications require microfluidic chip material to show compatibility with biochemical reactions (such as amplification reactions), and to have high transparency in the visible region and high chemical resistance. Also, preferably, manufacturing should be simple. The characteristic properties of cyclic olefin copolymer (COC) fulfills these requirements and offers new opportunities for the development of new forensic tests. In this work, the versatility of COC as material for lab-on-a-chip (LOC) systems in forensic applications has been explored by realizing two proof-of-principle devices. Chemical resistance and optical transparency were investigated for the development of an on-chip presumptive color test to indicate the presence of an illicit substance through applying absorption spectroscopy. Furthermore, the compatibility of COC with a DNA amplification reaction was verified by performing an on-chip multiple displacement amplification (MDA) reaction.

Fabrication and Applications of Microfluidic Devices: A Review

“…COPs/COCs have recently attracted considerable research interest in microfluidics due to their favorable properties, such as optical transparency in the visible and near-UV spectrum, enhanced chemical resistance, low water absorptivity (<0.01%), good electrical insulating properties, long-term stability of surface treatments, and an extremely low level of impurities [ 25 , 29 , 37 ]. These thermoplastics are useful for synthesis devices in which aggressive solvents are employed, being able to withstand acids (e.g., hydrogen chloride, sulfuric acid, and nitric acid); bases (e.g., sodium hydroxide and ammonia); and polar solvents (e.g., ethanol and acetone) [ 37 ].…”

“…COC chips can be employed for DNA amplification and the testing of samples in a simple, quick, and relatively sensitive manner. The best results can be acquired with sample quantities of less than one milligram or with a pure substance, and the result can be observed with the unaided eye [ 37 ]. Moreover, the DNA extraction chip can be coupled with an expert profile-interpretation software that allows law enforcement agencies to check whether there is a match between a person under custody and the DNA profiles recovered from unsolved crime cases [ 94 ].…”

Disposable DNA Amplification Chips with Integrated Low-Cost Heaters †

“…Fabrication methods suitable for mass production are thermoforming/embossing or injection molding [41]. One of the materials which is biocompatible and suitable for both industrial scale fabrication technologies is cyclic olefin copolymer (COC) [42], which is one of the materials used in the past as well [28,36,[43][44][45]. Guckenberger et al estimates the costs of injection molding of only 50 simple microfluidic devices on $47, but this becomes cheaper when the mass production stage is reached [41].…”

“…The chambers with the resistive heater on the backside, are intensively cleaned by rinsing with acetone, MilliQ DI water, ethanol, and isopropanol [45]. Each cleaning step was done 3 times and the chips are blow dried using N 2 gas.…”

Rapid Manufacturing of Multilayered Microfluidic Devices for Organ on a Chip Applications

“…As an alternative, the use of thermoplastics may overcome some drawbacks mentioned before, still conserving some of the PDMS properties such as optical clearance, biocompatibility, and chemical stability. By all of thermoplastics, PolyStyrene (PS), Cyclic Olefin Polymer (COP), and Cyclic Olefin Copolymer (COC) may be the more desirable materials for microfluidic devices because they do not absorb hydrophobic drugs [ 3 , 10 , 11 , 12 , 13 ]. Mild plasma treatment on PS and COP (final contact angle of ) helps to achieve good cell growth, similar to commercial ones [ 14 ].…”