Characterization and Electrochemical Analysis of Microelectrodes and the Interface with a Fabricated 3D-Printed Microfluidic Chip in an Upper-Division Analytical Course

Abstract

This work explores the interface between 3D-printing, material sciences, and microfluidics with electrochemical detection in an undergraduate laboratory. This work includes a module for the characterization and electrochemical analysis of microelectrodes that spans 4 weeks (3 h per week). Laboratory exercises include the fabrication of a 3D-printed device, examination of 3D-printing techniques, scanning electron microscopy (SEM), and electrochemistry. This interdisciplinary curricula exposed students to the process of designing a functioning microfluidic device. Students began by designing the microfluidic chip with AutoDesk Inventor. To gain a better understanding of the microelectrodes utilized in a microfluidic system, students explored the surfaces of various microelectrodes with SEM. On the basis of the visualization of the microelectrodes with SEM, students formed a hypothesis on the impact of electrode surface area on the sensitivity and limit of detection. Cyclic voltammetry in a classical three-electrode system was used to experimentally examine the relationship between electrode surface area and sensitivity. The module concluded with the use of the fabricated 3D-printed chip and amperometry to develop a calibration curve and determination of an unknown concentration of analyte. This work highlights the integration of 3D-printing, SEM, microfluidics, and electrochemistry into the upper-level undergraduate curriculum.

Stimulating Students’ Learning in Analytical Chemistry through an Environmental-Based CURE Project

“…Many of the students felt the analysis was personal because it affected their lives, and they felt a personal obligation to accurately determine the amount of Pb in their soil samples. The observed benefits to the students agree with other CURE laboratories in upper-level chemistry courses. − , Though publication of research is very important and boosts the self-confidence of the students involved, the benefits that students gain by engaging in research extend beyond articles published. The most important part of research for an undergraduate student is the transformation that takes place during the research process.…”

“…The observed benefits to the students agree with other CURE laboratories in upper-level chemistry courses. [19][20][21][22][23][24][25]31 Though publication of research is very important and boosts the selfconfidence of the students involved, the benefits that students gain by engaging in research extend beyond articles published. The most important part of research for an undergraduate student is the transformation that takes place during the research process.…”

“…The goals of implementing CURE projects in upper-level science courses are different from other CURE-based laboratories targeting introductory courses. ,− Students taking upper-level science courses have already demonstrated their interest and persistence in science. To this end, the objective was to engage a larger number of students with no prior research experience to help them to understand the research process and develop the ability to integrate theory to a real-life application.…”

Application of 3D Printers to Fabricate Low-Cost Electrode Components for Undergraduate Experiments and Research

“…With the increasing availability of 3D printers and associated user-friendly software at both educational institutions and public facilities such as libraries, their applications have been widespread in emerging technologies and educational tools. The use of 3D printing technology has been reported for printing educational models, − carbon nanotubes-based microsupercapacitors, copolymer nanostructures, hydrogels, laboratory equipment and hardware, including a colorimeter, fluorometer, polarimeter, optical hardware, chemical experiments, contact angle measurement system, microfluidic devices, , document camera, and a mirror mount …”

Design-Based Learning Framework for Introducing Factorial Experimental Design and Lab-on-a-Chip Separations in an Instrumental Chemistry Laboratory

“…We developed a simple, affordable, and rapid prototyping method to design, fabricate, and test microfluidic lab-on-a-chip devices capable of chemical separation by microcapillary electrophoresis (μCE). Many lab-on-a-chip fabrication methods have been reported in this Journal as well as others based on photolithography, milling, casting, or hot lamination techniques, − including the fabrication of μCE devices. ,− Although useful, all of these methods require specialty equipment, extended durations for fabrication, or expensive or dangerous reagents that pose accessibility limitations to undergraduate courses . Our fabrication process uses a commonly available computer-controlled (i.e., CNC) CO 2 laser engraver in combination with a simple solvothermal sealing method to fabricate functional devices from cheap acrylic sheets (Figure ).…”