Biomedical Engineering and Bioengineering Commons^™

Protecting Crops From Abiotic Stress: Copper Oxide Nanoparticle Effects On Wheat And A Beneficial Rhizobacterium, Matthew Potter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nanoparticles (NPs) are defined as particles less than 100 nm in at least one dimension. CuO NPs have possible applications in agriculture as micronutrient sources, pesticides, and enhancers of crop stress tolerance. Here, three aspects of CuO NP agricultural applications are studied: 1) the potential of CuO NPs to prevent wheat lodging-when crops irreversibly fall over; 2) CuO NP-induced drought tolerance in wheat seedlings; and 3) the effects of CuO NPs on outer membrane vesicle (OMV) production by Pseudomonas chlororaphis O6 (PcO6), a plant-health promoting bacterium.

Wheat grown 7 d exposed to CuO NPs in the growth matrix …

A Multi-Scale Approach To Study Biochemical And Biophysical Aspects Of Resveratrol On Diesel Exhaust Particle-Human Primary Lung Cell Interaction, Wei Zhang, Qifei Li, Mingjie Tang, Han Zhang, Xiaoping Sun, Sige Zou, Judy L. Jensen, Theodore G. Liou, Anhong Zhou

Biological Engineering Faculty Publications

Diesel exhaust particles (DEPs) are major air pollutants that lead to numerous human disorders, especially pulmonary diseases, partly through the induction of oxidative stress. Resveratrol is a polyphenol that ameliorates the production of reactive oxygen species (ROS) and delays aging-related processes. Herein we studied the cytoprotective effect of resveratrol on DEP-exposed human lung cells in a factorial experimental design. This work investigates biophysical features including cellular compositions and biomechanical properties, which were measured at the single-cell level using confocal Raman microspectroscopy (RM) and atomic force microscopy (AFM), respectively. Principal component analysis (PCA), hierarchical cluster analysis (HCA) and partial least square …

The Use Of Microfluidics And Dielectrophoresis For Separation, Concentration, And Identification Of Bacteria, Cynthia Hanson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Typical bacterial analysis involves culturing and visualizing colonies on an array of agar plates. The growth patterns and colors among the array are used to identify the bacteria. For fast growing bacteria such as Escherichia coli, analysis will take one to two days. However, slow growing bacteria such as mycobacteria can take weeks to identify. In addition, there are some species of bacteria that are viable but nonculturable. This lengthy analysis time is unacceptable for life-threatening infections and emergency situations. It is clear that to decrease the analysis of the bacteria, the culturing and growth steps must be avoided. …

Microfluidic Chip For Non-Invasive Analysis Of Tumor Cells Interaction With Anti-Cancer Drug Doxorubicin By Afm And Raman Spectroscopy, Han Zhang, Lifu Xiao, Qifei Li, Xiaojun Qi, Anhong Zhou

Biological Engineering Faculty Publications

Raman spectroscopy has been playing an increasingly significant role for cell classification. Here, we introduce a novel microfluidic chip for non-invasive Raman cell natural fingerprint collection. Traditional Raman spectroscopy measurement of the cells grown in a Polydimethylsiloxane (PDMS) based microfluidic device suffers from the background noise from the substrate materials of PDMS when intended to apply as an in vitro cell assay. To overcome this disadvantage, the current device is designed with a middle layer of PDMS layer sandwiched by two MgF2slides which minimize the PDMS background signal in Raman measurement. Three cancer cell lines, including a human lung cancer …

In Vivo Raman Spectroscopy For Biochemical Monitoring Of The Human Cervix Throughout Pregnancy, Christine M. O'Brien, Elizabeth Vargis, Amy Rudin, James C. Slaughter, Giju Thomas, J. Michael Newton, Jeff Reese, Kelly A. Bennett, Anita Mahadevan-Jansen

Biological Engineering Faculty Publications

Background

The cervix must undergo significant biochemical remodeling to allow for successful parturition. This process is not fully understood, especially in instances of spontaneous preterm birth. In vivo Raman spectroscopy is an optical technique that can be used to investigate the biochemical composition of tissue longitudinally and noninvasively in human beings, and has been utilized to measure physiology and disease states in a variety of medical applications.

Objective

The purpose of this study is to measure in vivo Raman spectra of the cervix throughout pregnancy in women, and to identify biochemical markers that change with the preparation for delivery and …

Alternative Cdep Design To Facilitate Cell Isolation For Identification By Raman Spectroscopy, Cynthia Hanson, Elizabeth Vargis

Biological Engineering Faculty Publications

Dielectrophoresis (DEP) uses non-uniform electric fields to cause motion in particles due to the particles' intrinsic properties. As such, DEP is a well-suited label-free means for cell sorting. Of the various methods of implementing DEP, contactless dielectrophoresis (cDEP) is advantageous as it avoids common problems associated with DEP, such as electrode fouling and electrolysis. Unfortunately, cDEP devices can be difficult to fabricate, replicate, and reuse. In addition, the operating parameters are limited by the dielectric breakdown of polydimethylsiloxane (PDMS). This study presents an alternative way to fabricate a cDEP device allowing for higher operating voltages, improved replication, and the opportunity …

The Use Of Microfluidics And Dielectrophoresis For Separation, Concentration, And Identification Of Bacteria, Cynthia Hanson, Michael Sieverts, Karen Tew, Annelise Dykes, Michaela Salisbury, Elizabeth Vargis

Biological Engineering Faculty Publications

Traditional bacterial identification methods take one to two days to complete, relying on large bacteria colonies for visual identification. In order to decrease this analysis time in a cost-effective manner, a method to sort and concentrate bacteria based on the bacteria's characteristics itself is needed. One example of such a method is dielectrophoresis, which has been used by researchers to separate bacteria from sample debris and sort bacteria according to species. This work presents variations in which dielectrophoresis can be performed and their associated drawbacks and benefits specifically to bacterial identification. In addition, a potential microfluidic design will be discussed.

Investigation Of Bone And Calcium Phosphate Coatings And Crystallinity Determination Using Raman Microspectroscopy, C. J. De Grauw, J. D. De Bruijn, C. Otto, J. Greve

Cells and Materials

Conventional spontaneous Raman micro-spectroscopy was used for the investigation of bone and calcium phosphate coatings on bone-implant surfaces. Chemical and structural changes at the bone-coating interface could be monitored on a microscopic scale. It was shown that the crystallinity did not vary within the crystalline apatite and amorphous calcium phosphate coatings, while the density within each coating did vary. Different degrees of crystallinity in coatings were investigated for a series of plasma-sprayed apatite coatings. It is concluded that Raman microspectroscopy is an easy non-destructive way to obtain information about the apatite structure and the degree of crystallinity.