The Print, Cut, and Laminate Method: Rapid Microfluidic Prototyping for Clinical and Forensic Applications

The detection and analysis of a variety of biochemical markers is essential in many applications, including, but not limited to, biomedical sciences, forensics, and clinical diagnostics. Often, conventional instrumentation utilized for these purposes are expensive and non-portable, and require labor-intensive, time consuming, and expensive assays that demand highly trained personnel. With the advancement of microfluidic technology, many of these limitations can be mitigated, with extensive research focused on creating fully integrated and automated devices and systems that perform complete biochemical analyses with the simple touch of a button. The presented research focuses on two specific applications, clinical diagnostic quantification and forensic human identification, where microfluidic technology and an inexpensive, rapid prototyping fabrication method have been utilized as potential solutions to fulfill these goals.
The aim of the clinical research was to develop an inexpensive and simplified microdevice capable of clinical diagnostic quantification of multiple blood parameters. The proof-of-concept of a fully integrated centrifugal device that successfully quantifies total protein, albumin, and hematocrit concentrations from a few drops of blood will be discussed. In addition, an inexpensive disc will be presented that can provide a clinically accurate hematocrit value from a finger prick in < 8 minutes. Finally, the development of a phototreatment image analysis methodology that can provide a total bilirubin concentration from <5 µL of plasma in a completely reagentless manner will be presented.
Additional work in forensic applications will be highlighted that is aimed at developing an inexpensive and rapid platform for human identification using short tandem repeat (STR) analysis. The development of an inexpensive device fabricated through the print, cut, and laminate fabrication protocol, that performs enzymatic DNA extraction from a buccal swab sample in <3 minutes will be discussed. The resulting DNA is successfully shown to be compatible with PCR amplification to yield a STR profile. Finally, a microfluidic device is described that can perform DNA separation with 2 base resolution in a microchannel only 4 cm in length and with integrated custom gold leaf electrodes. Further advancement resulted in a fully-integrated microdevice and completely automated system capable of DNA extraction, multiplexed STR-based PCR amplification, and fragment separation, for rapid human identification by the simple touch of a button.