Adrienne Minerick | Michigan Technological University (original) (raw)

Papers by Adrienne Minerick

Chemical engineering education, Mar 28, 2018

A freshman Introduction to Chemical Engineering seminar course can be a useful part of the underg... more A freshman Introduction to Chemical Engineering seminar course can be a useful part of the undergraduate curriculum. Goals for such a course range from gaining an appreciation for chemical engineering manufacturing processes and safety, to an overview of the subject areas students will become proficient in by the time they graduate. This article discusses two experiments, Charged Up on Electrophoresis and Brewing with Bioreactors, which are used to enhance the introductory chemical engineering experience. Electrophoresis and bioreactor processes are brought to life via an introductory lecture, assignments, and a simple desktop experiment that utilizes inexpensive supplies to demonstrate electrophoretic separations and bioprocessing. Advantages of these hands-on experiences include that they are not dependent on the availability of lab space, and students have a unique experience to link into their evolving understanding of chemical engineering concepts. Complete supply lists, pre-assignment exercises, experimental procedures, and lab mats are discussed for both experiments and available for instructor use.

Langmuir, May 4, 2022

The ability to generate stable, spatiotemporally controllable concentration gradients is critical... more The ability to generate stable, spatiotemporally controllable concentration gradients is critical for both electrokinetic and biological applications such as directional wetting and chemotaxis. Electrochemical techniques for generating solution and surface gradients display benefits such as simplicity, controllability, and compatibility with automation. Here, we present an exploratory study for generating micro-scale spatiotemporally controllable gradients using a reaction-free electrokinetic technique in a microfluidic environment. Methanol solutions with ionic Fluorescein isothiocyanate (FITC) molecules were used as an illustrative electrolyte. Spatially non-uniform alternating current (AC) electric fields were applied using hafnium dioxide (HfO2) coated Ti/Au electrode pairs. Results from spatial and temporal analysis, along with control experiments suggest that the FITC ion concentration gradient in bulk fluid (over 50 µm from the electrode) was established due to spatial variation of electric field density, and was independent of electrochemical reactions at the electrode surface. The established ion concentration gradients depended on both amplitudes and the frequencies of the oscillating AC electric field. Overall, this work reports a novel approach for generating stable and spatiotemporally tunable gradients in a microfluidic chamber using a reaction-free electrochemical methodology.

Experimental Eye Research, Feb 1, 2017

Two separate liquid chromatography (LC)-mass spectrometry (MS) methods were developed for determi... more Two separate liquid chromatography (LC)-mass spectrometry (MS) methods were developed for determination and quantification of water-soluble and fat-soluble vitamins in human tear and blood serum samples. The water-soluble vitamin method was originally developed to detect vitamins B 1 , B 2 , B 3 (nicotinamide), B 5 , B 6 (pyridoxine), B 7 , B 9 and B 12 while the fat-soluble vitamin method detected vitamins A, D 3 , 25(OH)D 3, E and K 1. These methods were then validated with tear and blood serum samples. In this data in brief article, we provide details on the two LC-MS methods development, methods sensitivity, as well as precision and accuracy for determination of vitamins in human tears and blood serum. These methods were then used to determine the vitamin concentrations in infant and parent samples under a clinical study which were reported in "Determination of Water-Soluble and Fat-Soluble Vitamins in Tears and Blood Serum of Infants and Parents by Liquid Chromatography/Mass Spectrometry

Routledge eBooks, May 6, 2022

Chemical engineering education, Mar 28, 2018

She was also the 2016-2017 chair of the ASEE Diversity Committee. Her research interests also inc... more She was also the 2016-2017 chair of the ASEE Diversity Committee. Her research interests also include inductive teaching in engineering pedagogy, spatial visualization skills, and increasing participation of underserved and underrepresented groups in engineering. She has been honored by the American Society of Engineering Education (ASEE) with several teaching awards such as the National Outstanding Teaching Medal and the Quinn Award for experiential learning. She is the founding faculty advisor of Rowan's oSTEM Chapter and PI on the NSF Project "A Virtual Community of Practice for Promoting LGBTQ Equality in Engineering. "

2006 Annual Conference & Exposition, Jun 18, 2006

This contribution outlines a strategy that the author has used to counteract literature lethargy ... more This contribution outlines a strategy that the author has used to counteract literature lethargy and train beginning researchers how to efficiently learn from and critique articles. Journal Club is a weekly meeting with all members of the research group where a research article related to each student's project is discussed by the entire research group. Due to multiple projects in the lab, each researcher contributes to discussions of articles tangentially related to their own research; this is a long-term benefit because it increases the breadth of each individual's knowledge. The discussion questions strive to increase the depth of knowledge in each topic. Lastly, the student involvement in discussions teaches critical thinking and aids in developing foresight to more effectively plan experiments. Outcomes of the Journal Club activity have been increased student knowledge of the literature, decreased apprehension in younger students toward understanding technical publications, and a slight increase in productivity towards publication goals within the group. Including this weekly meeting as an independent study course for credit also encourages all students to read the articles prior to the meeting and enhances participation in group discussions.

2010 Annual Conference & Exposition, Jun 20, 2010

She received her B.S. degree in Biological Sciences from Clemson University in 1996 and her M.S. ... more She received her B.S. degree in Biological Sciences from Clemson University in 1996 and her M.S. and Ph.D. degrees in Chemical Engineering from Clemson University in 2001 and 2005. Dr. Walters' research involves the development and surface modification of stimuliresponsive and bio-inspired polymeric materials. She has been a member of ASEE since 2002.

Micromachines

Dielectrophoresis (DEP), a precision nonlinear electrokinetic tool utilized within microfluidic d... more Dielectrophoresis (DEP), a precision nonlinear electrokinetic tool utilized within microfluidic devices, can induce bioparticle polarization that manifests as motion in the electric field; this phenomenon has been leveraged for phenotypic cellular and biomolecular detection, making DEP invaluable for diagnostic applications. As device operation times lengthen, reproducibility and precision decrease, which has been postulated to be caused by ion gradients within the supporting electrolyte medium. This research focuses on characterizing pH gradients above, at, and below the electrode charging frequency (0.2–1.4 times charging frequency) in an aqueous electrolyte solution in order to extend the parameter space for which microdevice-imposed artifacts on cells in clinical diagnostic devices have been characterized. The nonlinear alternating current (AC) electric fields (0.07 Vpp/μm) required for DEP were generated via planar T-shaped and star-shaped microelectrodes overlaid by a 70 μm hi...

She has worked as an intern research engineer at Bayer Biologicals, coop chemist at American Air ... more She has worked as an intern research engineer at Bayer Biologicals, coop chemist at American Air Liquide, Chicago during her MS degree. Before joining MSU she was at Warren Analytical, Greeley, CO for 1.5 years as a Research Associate Chemist. Her research involves building lab-on-a-chip device for medical diagnostic applications. She recently won an award for maximum number of publications in a year from chemical engineering department at MSU. She is associated with Medical Micro Device Engineering Laboratory (M.D.-ERL) at MSU working under Dr.

Increasing the number of female graduate students in engineering education has always been challe... more Increasing the number of female graduate students in engineering education has always been challenging. This study presented here examines the preferences and self-recognized challenges identified by international female graduate engineering students at U.S. schools. These findings can also be used by institutions to attract more female students in graduate engineering programs by integrating in ongoing recruitment and retention efforts. Research findings are based on a comprehensive online survey designed and conducted by the authors, who are of diverse nationality, educational background, and gender. Male and female international graduate students and alumni at U.S. schools were invited to complete the online survey. Results indicate that preferences of international students to choose a graduate school differ by gender and female students tend to choose a school on a different set of criteria compared to their male colleagues. Common challenges faced and preferences adopted in ch...

Langmuir, 2020

The ability to monitor the status and progression of viral infections is important for developmen... more The ability to monitor the status and progression of viral infections is important for development and screening of new antiviral drugs. Previous research illustrated that the osmolyte glycine (Gly) reduced porcine parvovirus (PPV) infection in porcine kidney (PK-13) cells by stabilizing the capsid protein and preventing virus capsid assembly into viable virus particles. Dielectrophoresis (DEP) was examined herein as a noninvasive, electric fieldand frequency-dependent tool for real-time monitoring of PK-13 cell responses to obtain information about membrane barrier functionality and polarization. DEP responses of PK-13 cells were compared to those of PPV-infected cells in the absence and presence of the osmolyte glycine. With infection progression, PK-13 DEP spectra shifted toward lower frequencies, reducing crossover frequencies (f CO). The spherical single-shell model was used to extract PK-13 cell dielectric properties. Upon PPV infection, specific membrane capacitance increased over the time progression of virus attachment, penetration, and capsid protein production and assembly. Following glycine treatment, the DEP spectra displayed attenuated f CO and specific membrane capacitance values shifted back toward uninfected PK-13 cell values. These results suggest that DEP can be used to noninvasively monitor the viral infection cycle and screen antiviral compounds. DEP can augment traditional tools by elucidating membrane polarization changes related to drug mechanisms that interrupt the virus infection cycle.

2011 ASEE Annual Conference & Exposition Proceedings

, where she was a tenured Associate Professor. She received her M.S. and Ph.D. from the Universit... more , where she was a tenured Associate Professor. She received her M.S. and Ph.D. from the University of Notre Dame in 2003 and B.S. from Michigan Technological University in 1998. Adrienne's research interests include electrokinetics and the development of biomedical microdevices. She earned a 2007 NSF CAREER award; her group has published in the Proceedings of the National Academy of Science, Lab on a Chip, and had an AIChE Journal cover. She is an active mentor of undergraduate researchers and served as co-PI on an NSF REU site. Research within her Medical micro-Device Engineering Research Laboratory (M.D. ERL) also inspires the development of Desktop Experiment Modules (DEMos) for use in chemical engineering classrooms or as outreach activities in area schools. Adrienne has been an active member of ASEE's WIED, ChED, and NEE leadership teams since 2003.

2011 ASEE Annual Conference & Exposition Proceedings

, where she was a tenured Associate Professor. She received her M.S. and Ph.D. from the Universit... more , where she was a tenured Associate Professor. She received her M.S. and Ph.D. from the University of Notre Dame in 2003 and B.S. from Michigan Technological University in 1998. Adrienne's research interests include electrokinetics and the development of biomedical microdevices. She earned a 2007 NSF CAREER award; her group has published in the Proceedings of the National Academy of Science, Lab on a Chip, and had an AIChE Journal cover. She is an active mentor of undergraduate researchers and served as co-PI on an NSF REU site. Research within her Medical micro-Device Engineering Research Laboratory (M.D. ERL) also inspires the development of Desktop Experiment Modules (DEMos) for use in chemical engineering classrooms or as outreach activities in area schools. Adrienne has been an active member of ASEE's WIED, ChED, and NEE leadership teams since 2003.

2020 ASEE Virtual Annual Conference Content Access Proceedings

is Dean of the College of Computing at Michigan Tech. She received her M.S. and Ph.D. from the Un... more is Dean of the College of Computing at Michigan Tech. She received her M.S. and Ph.D. from the University of Notre Dame and B.S. from Michigan Tech. Adrienne is a fellow of ASEE, fellow of the American Association for the Advancement of Science (AAAS), former President of the AES Electrophoresis Society, and a Michigan Professor of the Year Nominee, which illustrate her dual passion for research and education's impact on individuals and societal advances. Adrienne's research interests include electrokinetics, predominantly dielectrophoretic characterizations of cells, and the development of biomedical microdevices. Research within her Medical micro-Device Engineering Research Laboratory (M.D.-ERL) also inspires the development of Desktop Experiment Modules (DEMos) for use in chemical engineering classrooms or as outreach activities in area schools (see www.mderl.org). Adrienne is past Chair of ASEE's Diversity Committee and past PIC I Chair; she has previously served on WIED, ChED, and NEE leadership teams and has contributed to over 40 ASEE conference proceedings articles.

Thin Solid Films, 2018

Many biological lab-on-a-chip applications require electrical and optical manipulation as well as... more Many biological lab-on-a-chip applications require electrical and optical manipulation as well as detection of cells and biomolecules. This provides an intriguing challenge to design robust microdevices that resist adverse electrochemical side reactions yet achieve optical transparency. Physical isolation of biological samples from microelectrodes can prevent contamination, electrode fouling, and electrochemical byproducts; thus this manuscript explores hafnium oxide (HfO 2) films-originating from traditional transistor applicationsfor suitability in electrokinetic microfluidic devices for biological applications. HfO 2 films with deposition times of 6.5, 13, and 20 minutes were sputter deposited onto silicon and glass substrates. The structural, optical, and electrical properties of the HfO 2 films were investigated using atomic force microscopy (AFM), X-ray diffraction, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, ellipsometry, and capacitance voltage. Electric potential simulations of the HfO 2 films and a biocompatibility study provided additional insights. Film grain size after corrosive Piranha treatment was observed via AFM. The crystalline structure investigated via X-ray diffraction revealed all films exhibited the (111) characteristic peak with thicker films exhibiting multiple peaks indicative of anisotropic structures. Energy dispersive X-ray spectroscopy via field emission scanning electron microscopy and Fourier transform infrared spectroscopy both corroborated the atomic ratio of the films as HfO 2. Ellipsometry data from Si yielded thicknesses of 58, 127, and 239 nm and confirmed refractive index and extinction coefficients within the normal range for HfO 2 ; glass data yielded unreliable thickness verifications due to film and substrate transparency. Capacitance-voltage results produced an average dielectric constant of 20.32, and the simulations showed that HfO 2 dielectric characteristics were sufficient to electrically passivate planar microelectrodes. HfO 2 biocompatibility was determined with human red blood cells by quantifying the hemolytic potential of the HfO 2 films. Overall results support hafnium oxide as a viable passivation material for biological lab-on-a-chip applications.

Chemical engineering education, Mar 28, 2018

A freshman Introduction to Chemical Engineering seminar course can be a useful part of the underg... more A freshman Introduction to Chemical Engineering seminar course can be a useful part of the undergraduate curriculum. Goals for such a course range from gaining an appreciation for chemical engineering manufacturing processes and safety, to an overview of the subject areas students will become proficient in by the time they graduate. This article discusses two experiments, Charged Up on Electrophoresis and Brewing with Bioreactors, which are used to enhance the introductory chemical engineering experience. Electrophoresis and bioreactor processes are brought to life via an introductory lecture, assignments, and a simple desktop experiment that utilizes inexpensive supplies to demonstrate electrophoretic separations and bioprocessing. Advantages of these hands-on experiences include that they are not dependent on the availability of lab space, and students have a unique experience to link into their evolving understanding of chemical engineering concepts. Complete supply lists, pre-assignment exercises, experimental procedures, and lab mats are discussed for both experiments and available for instructor use.

Langmuir, May 4, 2022

The ability to generate stable, spatiotemporally controllable concentration gradients is critical... more The ability to generate stable, spatiotemporally controllable concentration gradients is critical for both electrokinetic and biological applications such as directional wetting and chemotaxis. Electrochemical techniques for generating solution and surface gradients display benefits such as simplicity, controllability, and compatibility with automation. Here, we present an exploratory study for generating micro-scale spatiotemporally controllable gradients using a reaction-free electrokinetic technique in a microfluidic environment. Methanol solutions with ionic Fluorescein isothiocyanate (FITC) molecules were used as an illustrative electrolyte. Spatially non-uniform alternating current (AC) electric fields were applied using hafnium dioxide (HfO2) coated Ti/Au electrode pairs. Results from spatial and temporal analysis, along with control experiments suggest that the FITC ion concentration gradient in bulk fluid (over 50 µm from the electrode) was established due to spatial variation of electric field density, and was independent of electrochemical reactions at the electrode surface. The established ion concentration gradients depended on both amplitudes and the frequencies of the oscillating AC electric field. Overall, this work reports a novel approach for generating stable and spatiotemporally tunable gradients in a microfluidic chamber using a reaction-free electrochemical methodology.

Experimental Eye Research, Feb 1, 2017

Two separate liquid chromatography (LC)-mass spectrometry (MS) methods were developed for determi... more Two separate liquid chromatography (LC)-mass spectrometry (MS) methods were developed for determination and quantification of water-soluble and fat-soluble vitamins in human tear and blood serum samples. The water-soluble vitamin method was originally developed to detect vitamins B 1 , B 2 , B 3 (nicotinamide), B 5 , B 6 (pyridoxine), B 7 , B 9 and B 12 while the fat-soluble vitamin method detected vitamins A, D 3 , 25(OH)D 3, E and K 1. These methods were then validated with tear and blood serum samples. In this data in brief article, we provide details on the two LC-MS methods development, methods sensitivity, as well as precision and accuracy for determination of vitamins in human tears and blood serum. These methods were then used to determine the vitamin concentrations in infant and parent samples under a clinical study which were reported in "Determination of Water-Soluble and Fat-Soluble Vitamins in Tears and Blood Serum of Infants and Parents by Liquid Chromatography/Mass Spectrometry

Routledge eBooks, May 6, 2022

Chemical engineering education, Mar 28, 2018

She was also the 2016-2017 chair of the ASEE Diversity Committee. Her research interests also inc... more She was also the 2016-2017 chair of the ASEE Diversity Committee. Her research interests also include inductive teaching in engineering pedagogy, spatial visualization skills, and increasing participation of underserved and underrepresented groups in engineering. She has been honored by the American Society of Engineering Education (ASEE) with several teaching awards such as the National Outstanding Teaching Medal and the Quinn Award for experiential learning. She is the founding faculty advisor of Rowan's oSTEM Chapter and PI on the NSF Project "A Virtual Community of Practice for Promoting LGBTQ Equality in Engineering. "

2006 Annual Conference & Exposition, Jun 18, 2006

This contribution outlines a strategy that the author has used to counteract literature lethargy ... more This contribution outlines a strategy that the author has used to counteract literature lethargy and train beginning researchers how to efficiently learn from and critique articles. Journal Club is a weekly meeting with all members of the research group where a research article related to each student's project is discussed by the entire research group. Due to multiple projects in the lab, each researcher contributes to discussions of articles tangentially related to their own research; this is a long-term benefit because it increases the breadth of each individual's knowledge. The discussion questions strive to increase the depth of knowledge in each topic. Lastly, the student involvement in discussions teaches critical thinking and aids in developing foresight to more effectively plan experiments. Outcomes of the Journal Club activity have been increased student knowledge of the literature, decreased apprehension in younger students toward understanding technical publications, and a slight increase in productivity towards publication goals within the group. Including this weekly meeting as an independent study course for credit also encourages all students to read the articles prior to the meeting and enhances participation in group discussions.

2010 Annual Conference & Exposition, Jun 20, 2010

She received her B.S. degree in Biological Sciences from Clemson University in 1996 and her M.S. ... more She received her B.S. degree in Biological Sciences from Clemson University in 1996 and her M.S. and Ph.D. degrees in Chemical Engineering from Clemson University in 2001 and 2005. Dr. Walters' research involves the development and surface modification of stimuliresponsive and bio-inspired polymeric materials. She has been a member of ASEE since 2002.

Micromachines

Dielectrophoresis (DEP), a precision nonlinear electrokinetic tool utilized within microfluidic d... more Dielectrophoresis (DEP), a precision nonlinear electrokinetic tool utilized within microfluidic devices, can induce bioparticle polarization that manifests as motion in the electric field; this phenomenon has been leveraged for phenotypic cellular and biomolecular detection, making DEP invaluable for diagnostic applications. As device operation times lengthen, reproducibility and precision decrease, which has been postulated to be caused by ion gradients within the supporting electrolyte medium. This research focuses on characterizing pH gradients above, at, and below the electrode charging frequency (0.2–1.4 times charging frequency) in an aqueous electrolyte solution in order to extend the parameter space for which microdevice-imposed artifacts on cells in clinical diagnostic devices have been characterized. The nonlinear alternating current (AC) electric fields (0.07 Vpp/μm) required for DEP were generated via planar T-shaped and star-shaped microelectrodes overlaid by a 70 μm hi...

She has worked as an intern research engineer at Bayer Biologicals, coop chemist at American Air ... more She has worked as an intern research engineer at Bayer Biologicals, coop chemist at American Air Liquide, Chicago during her MS degree. Before joining MSU she was at Warren Analytical, Greeley, CO for 1.5 years as a Research Associate Chemist. Her research involves building lab-on-a-chip device for medical diagnostic applications. She recently won an award for maximum number of publications in a year from chemical engineering department at MSU. She is associated with Medical Micro Device Engineering Laboratory (M.D.-ERL) at MSU working under Dr.

Increasing the number of female graduate students in engineering education has always been challe... more Increasing the number of female graduate students in engineering education has always been challenging. This study presented here examines the preferences and self-recognized challenges identified by international female graduate engineering students at U.S. schools. These findings can also be used by institutions to attract more female students in graduate engineering programs by integrating in ongoing recruitment and retention efforts. Research findings are based on a comprehensive online survey designed and conducted by the authors, who are of diverse nationality, educational background, and gender. Male and female international graduate students and alumni at U.S. schools were invited to complete the online survey. Results indicate that preferences of international students to choose a graduate school differ by gender and female students tend to choose a school on a different set of criteria compared to their male colleagues. Common challenges faced and preferences adopted in ch...

Langmuir, 2020

The ability to monitor the status and progression of viral infections is important for developmen... more The ability to monitor the status and progression of viral infections is important for development and screening of new antiviral drugs. Previous research illustrated that the osmolyte glycine (Gly) reduced porcine parvovirus (PPV) infection in porcine kidney (PK-13) cells by stabilizing the capsid protein and preventing virus capsid assembly into viable virus particles. Dielectrophoresis (DEP) was examined herein as a noninvasive, electric fieldand frequency-dependent tool for real-time monitoring of PK-13 cell responses to obtain information about membrane barrier functionality and polarization. DEP responses of PK-13 cells were compared to those of PPV-infected cells in the absence and presence of the osmolyte glycine. With infection progression, PK-13 DEP spectra shifted toward lower frequencies, reducing crossover frequencies (f CO). The spherical single-shell model was used to extract PK-13 cell dielectric properties. Upon PPV infection, specific membrane capacitance increased over the time progression of virus attachment, penetration, and capsid protein production and assembly. Following glycine treatment, the DEP spectra displayed attenuated f CO and specific membrane capacitance values shifted back toward uninfected PK-13 cell values. These results suggest that DEP can be used to noninvasively monitor the viral infection cycle and screen antiviral compounds. DEP can augment traditional tools by elucidating membrane polarization changes related to drug mechanisms that interrupt the virus infection cycle.

2011 ASEE Annual Conference & Exposition Proceedings

, where she was a tenured Associate Professor. She received her M.S. and Ph.D. from the Universit... more , where she was a tenured Associate Professor. She received her M.S. and Ph.D. from the University of Notre Dame in 2003 and B.S. from Michigan Technological University in 1998. Adrienne's research interests include electrokinetics and the development of biomedical microdevices. She earned a 2007 NSF CAREER award; her group has published in the Proceedings of the National Academy of Science, Lab on a Chip, and had an AIChE Journal cover. She is an active mentor of undergraduate researchers and served as co-PI on an NSF REU site. Research within her Medical micro-Device Engineering Research Laboratory (M.D. ERL) also inspires the development of Desktop Experiment Modules (DEMos) for use in chemical engineering classrooms or as outreach activities in area schools. Adrienne has been an active member of ASEE's WIED, ChED, and NEE leadership teams since 2003.

2011 ASEE Annual Conference & Exposition Proceedings

, where she was a tenured Associate Professor. She received her M.S. and Ph.D. from the Universit... more , where she was a tenured Associate Professor. She received her M.S. and Ph.D. from the University of Notre Dame in 2003 and B.S. from Michigan Technological University in 1998. Adrienne's research interests include electrokinetics and the development of biomedical microdevices. She earned a 2007 NSF CAREER award; her group has published in the Proceedings of the National Academy of Science, Lab on a Chip, and had an AIChE Journal cover. She is an active mentor of undergraduate researchers and served as co-PI on an NSF REU site. Research within her Medical micro-Device Engineering Research Laboratory (M.D. ERL) also inspires the development of Desktop Experiment Modules (DEMos) for use in chemical engineering classrooms or as outreach activities in area schools. Adrienne has been an active member of ASEE's WIED, ChED, and NEE leadership teams since 2003.

2020 ASEE Virtual Annual Conference Content Access Proceedings

is Dean of the College of Computing at Michigan Tech. She received her M.S. and Ph.D. from the Un... more is Dean of the College of Computing at Michigan Tech. She received her M.S. and Ph.D. from the University of Notre Dame and B.S. from Michigan Tech. Adrienne is a fellow of ASEE, fellow of the American Association for the Advancement of Science (AAAS), former President of the AES Electrophoresis Society, and a Michigan Professor of the Year Nominee, which illustrate her dual passion for research and education's impact on individuals and societal advances. Adrienne's research interests include electrokinetics, predominantly dielectrophoretic characterizations of cells, and the development of biomedical microdevices. Research within her Medical micro-Device Engineering Research Laboratory (M.D.-ERL) also inspires the development of Desktop Experiment Modules (DEMos) for use in chemical engineering classrooms or as outreach activities in area schools (see www.mderl.org). Adrienne is past Chair of ASEE's Diversity Committee and past PIC I Chair; she has previously served on WIED, ChED, and NEE leadership teams and has contributed to over 40 ASEE conference proceedings articles.

Thin Solid Films, 2018

Many biological lab-on-a-chip applications require electrical and optical manipulation as well as... more Many biological lab-on-a-chip applications require electrical and optical manipulation as well as detection of cells and biomolecules. This provides an intriguing challenge to design robust microdevices that resist adverse electrochemical side reactions yet achieve optical transparency. Physical isolation of biological samples from microelectrodes can prevent contamination, electrode fouling, and electrochemical byproducts; thus this manuscript explores hafnium oxide (HfO 2) films-originating from traditional transistor applicationsfor suitability in electrokinetic microfluidic devices for biological applications. HfO 2 films with deposition times of 6.5, 13, and 20 minutes were sputter deposited onto silicon and glass substrates. The structural, optical, and electrical properties of the HfO 2 films were investigated using atomic force microscopy (AFM), X-ray diffraction, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, ellipsometry, and capacitance voltage. Electric potential simulations of the HfO 2 films and a biocompatibility study provided additional insights. Film grain size after corrosive Piranha treatment was observed via AFM. The crystalline structure investigated via X-ray diffraction revealed all films exhibited the (111) characteristic peak with thicker films exhibiting multiple peaks indicative of anisotropic structures. Energy dispersive X-ray spectroscopy via field emission scanning electron microscopy and Fourier transform infrared spectroscopy both corroborated the atomic ratio of the films as HfO 2. Ellipsometry data from Si yielded thicknesses of 58, 127, and 239 nm and confirmed refractive index and extinction coefficients within the normal range for HfO 2 ; glass data yielded unreliable thickness verifications due to film and substrate transparency. Capacitance-voltage results produced an average dielectric constant of 20.32, and the simulations showed that HfO 2 dielectric characteristics were sufficient to electrically passivate planar microelectrodes. HfO 2 biocompatibility was determined with human red blood cells by quantifying the hemolytic potential of the HfO 2 films. Overall results support hafnium oxide as a viable passivation material for biological lab-on-a-chip applications.