Physical Sciences and Mathematics Commons^™

Characterization Of Reagent Pencils For Deposition Of Reagents Onto Paper-Based Microfluidic Devices, Cheyenne H. Liu, Isabelle C. Noxon, Leah E. Cuellar, Amanda L. Thraen, Chad Immoos, Andres W. Martinez, Philip J. Costanzo

Chemistry and Biochemistry

Reagent pencils allow for solvent-free deposition of reagents onto paper-based microfluidic devices. The pencils are portable, easy to use, extend the shelf-life of reagents, and offer a platform for customizing diagnostic devices at the point of care. In this work, reagent pencils were characterized by measuring the wear resistance of pencil cores made from polyethylene glycols (PEGs) with different molecular weights and incorporating various concentrations of three different reagents using a standard pin abrasion test, as well as by measuring the efficiency of reagent delivery from the pencils to the test zones of paper-based microfluidic devices using absorption spectroscopy and …

Paper Microzone Plates As Analytical Tools For Studying Enzyme Stability: A Case Study On The Stabilization Of Horseradish Peroxidase Using Trehalose And Su-8 Epoxy Novolac Resin, Kirsten A. Ganaja, Cory Chaplan, Jingyi Zhang, Nathaniel W. Martinez, Andres W. Martinez

Chemistry and Biochemistry

Paper microzone plates in combination with a noncontact liquid handling robot were demonstrated as tools for studying the stability of enzymes stored on paper. The effect of trehalose and SU-8 epoxy novolac resin (SU-8) on the stability of horseradish peroxidase (HRP) was studied in both a short-term experiment, where the activity of various concentrations of HRP dried on paper were measured after 1 h, and a long-term experiment, where the activity of a single concentration of HRP dried and stored on paper was monitored for 61 days. SU-8 was found to stabilize HRP up to 35 times more than trehalose …

Paper-Based Diagnostic Devices, Spencer A. Schultz, Isabelle C. Noxon, Tyler A. Sisley, Andres W. Martinez

Chemistry and Biochemistry

This chapter will provide an overview of existing diagnostic devices made primarily out of paper and then focus on paper-based microfluidic devices, the next generation of paper-based diagnostic devices that promises to extend the use of paper as a material for fabricating diagnostic devices well into the future.

Chapter Contents:

• 2.1 Introduction
• 2.2 Current paper-based diagnostic devices
• 2.2.1 Dipstick devices
• 2.2.2 Lateral-flow devices
• 2.2.2.1 Vertical-flow devices
• 2.2.3 Paper-based arrays
• 2.3 Paper-based microfluidic devices
• 2.3.1 Fabrication of paper-based microfluidic devices
• 2.3.2 Applications of paper-based microfluidic devices
• 2.4 Conclusions
• References