Biomedical Engineering and Bioengineering Commons^™

Computational Design Of Fiber-Optic Probes For Biosensing, Suwarna Karna

Electrical Engineering Theses

This thesis presents a study on the optical characteristics of hollow-core photonic crystal fibers (HC-PCFs) with a band gap cladding structure and their applications in optical fiber sensing. This 800B HC-PCF exhibited excellent optical properties and has a flexible structure, which makes them suitable for a wide range of industrial applications. Finite element simulations and structural optimization designs were conducted using the surface plasmon resonance (SPR) technique to determine the optimal performance parameters of the 800B HC-PCF. The fiber was further modified using the SPR technique to improve its practical detection capabilities. The performance of the modified fiber was observed …

Ultrasensitive Tapered Optical Fiber Refractive Index, Erem Ujah, Meimei Lai, Gymama Slaughter

Electrical & Computer Engineering Faculty Publications

Refractive index (RI) sensors are of great interest for label-free optical biosensing. A tapered optical fiber (TOF) RI sensor with micron-sized waist diameters can dramatically enhance sensor sensitivity by reducing the mode volume over a long distance. Here, a simple and fast method is used to fabricate highly sensitive refractive index sensors based on localized surface plasmon resonance (LSPR). Two TOFs (l = 5 mm) with waist diameters of 5 µm and 12 µm demonstrated sensitivity enhancement at λ = 1559 nm for glucose sensing (5-45 wt%) at room temperature. The optical power transmission decreased with increasing glucose concentration due …

Development Of Fluorescent Hyaluronic Acid Nanoparticles For Intraoperative Tumor Detection, Nicholas E. Wojtynek

Theses & Dissertations

Surgical resection remains to be the primary treatment for the majority of solid tumors, including breast cancer. The complete removal of the primary tumor, local metastases, and metastatic lymph nodes dramatically improve a patient’s treatment outcome and prognosis. Nevertheless, surgeons are limited to tactile and visual cues in distinguishing malignant and healthy tissue. This can result in a positive surgical margin (PSM), which occurs when tumor goes undetected and is left behind in the surgical cavity. PSMs decreases a patient’s prognosis and necessitate additional treatment in the form of surgery, radiation, and chemotherapy. An emerging imaging modality, known as fluorescence-guided …

Cell Imaging And Data Analysis For Biomaterial-Mammalian Co-Cultures, Jefferson Pontsler

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Microscopic bioimaging is a useful approach to study cell-biomaterial interactions which are vital to the biomedical application of biomaterials. Through microscopic imaging, numerous cellular responses, such as proliferation, uptake, and death, can be recorded, characterized and analyzed.

In this thesis, I first provided basic introductions to the imaging techniques and analysis tools, especially those that are highly relevant to the studies of biomaterials and cell interactions. I also detailed the adaptation of these techniques and tools in the application of two specific research projects in biomaterials, with special focuses on the imaging and analysis.

The first project assessed the subtle …

Optical And X-Ray Technology Synergies Enabling Diagnostic And Therapeutic Applications In Medicine, Brian W. Pogue, Brian C. Wilson

Dartmouth Scholarship

X-ray and optical technologies are the two central pillars for human imaging and therapy. The strengths of x-rays are deep tissue penetration, effective cytotoxicity, and the ability to image with robust projection and computed-tomography methods. The major limitations of x-ray use are the lack of molecular specificity and the carcinogenic risk. In comparison, optical interactions with tissue are strongly scatter dominated, leading to limited tissue penetration, making imaging and therapy largely restricted to superficial or endoscopically directed tissues. However, optical photon energies are comparable with molecular energy levels, thereby providing the strength of intrinsic molecular specificity. Additionally, optical technologies are …

Multi-Beam Scan Analysis With A Clinical Linac For High Resolution Cherenkov-Excited Molecular Luminescence Imaging In Tissue., Mengyu Jeremy Jia, Peter Bruza, Lesley A. Jarvis, David J. Gladstone, Brian W. Pogue

Dartmouth Scholarship

Cherenkov-excited luminescence scanned imaging (CELSI) is achieved with external beam radiotherapy to map out molecular luminescence intensity or lifetime in tissue. Just as in fluorescence microscopy, the choice of excitation geometry can affect the imaging time, spatial resolution and contrast recovered. In this study, the use of spatially patterned illumination was systematically studied comparing scan shapes, starting with line scan and block patterns and increasing from single beams to multiple parallel beams and then to clinically used treatment plans for radiation therapy. The image recovery was improved by a spatial-temporal modulation-demodulation method, which used the ability to capture simultaneous images …

Development Of Spectroscopic Methods For Dynamic Cellular Level Study Of Biochemical Kinetics And Disease Progression, Anna M. Sitarski

Electronic Theses and Dissertations

One of the current fundamental objectives in biomedical research is understanding molecular and cellular mechanisms of disease progression. Recent work in genetics support the stochastic nature of disease progression on the single cell level. For example, recent work has demonstrated that cancer as a disease state is reached after the accumulation of damages that result in genetic errors. Other diseases like Huntingtons, Parkinsons, Alzheimers, cardiovascular disease are developed over time and their cellular mechanisms of disease transition are largely unknown. Modern techniques of disease characterization are perturbative, invasive and fully destructive to biological samples. Many methods need a probe or …

The Effect Of Hyperthermia On Doxorubicin Therapy And Nanoparticle Penetration In Multicellular Ovarian Cancer Spheroids, Abhignyan Nagesetti

FIU Electronic Theses and Dissertations

The efficient treatment of cancer with chemotherapy is challenged by the limited penetration of drugs into the tumor. Nanoparticles (10 – 100 nanometers) have emerged as a logical choice to specifically deliver chemotherapeutics to tumors, however, their transport into the tumor is also impeded owing to their bigger size compared to free drug moieties. Currently, monolayer cell cultures, as models for drug testing, cannot recapitulate the structural and functional complexity of in-vivo tumors. Furthermore, strategies to improve drug distribution in tumor tissues are also required. In this study, we hypothesized that hyperthermia (43°C) will improve the distribution of silica nanoparticles …

Cobalt Ferrite Nanoparticles Fabricated Via Co-Precipitation In Air: Overview Of Size Control And Magnetic Properties, Dennis Toledo

FIU Electronic Theses and Dissertations

Cobalt Ferrite has important, size-dependent magnetic properties. Consequently, an overview of particle size is important. Co-precipitation in air was the fabrication method used because it is comparatively simple and safe. The effects of three different reaction times including 1, 2, 3 hour(s) on particle size were compared. Also, the effectiveness of three different capping agents (Oleic Acid, Polyvinylpyrollidone (PVP), and Trisodium Citrate) in reducing aggregation and correspondingly particle size were examined. Using Welch’s analysis of variance (ANOVA) and the relevant post hoc tests, there was no significant difference (p=0.05) between reaction times of 1 hour and 2 hours, but there …

Developent Of A Phospholipid Encapsulation Process For Quantum Dots To Be Used In Biologic Applications, Logan Grimes

Master's Theses

The American Cancer Society predicts that 1,665,540 people will be diagnosed with cancer, and 585,720 people will die from cancer in 2014. One of the most common types of cancer in the United States is skin cancer. Melanoma alone is predicted to account for 10,000 of the cancer related deaths in 2014. As a highly mobile and aggressive form of cancer, melanoma is difficult to fight once it has metastasized through the body. Early detection in such varieties of cancer is critical in improving survival rates in afflicted patients. Present methods of detection rely on visual examination of suspicious regions …

Surface Functionalization And Bioconjugation Of Nanoparticles For Biomedical Applications, Longyan Chen

Electronic Thesis and Dissertation Repository

Colloidal inorganic nanoparticles (NPs) have been attracting considerable interest in biomedicine, from drug and gene delivery to imaging, sensing and diagnostics. It is essential to modify the surface of nanoparticles to have enhanced biocompatibility and functionality for the in vitro and in vivo applications, especially in delivering locally and recognizing biomolecules. Herein, the goal of this research work is to develop advanced NPs with well-tailored surface functionalities and/or bio-functionality for the applications in cell tracking and analytes detection.

In the first project, quantum dots incorporating with gelatin nanoparticles (QDs-GNPs) have been developed for bioimaging applications. Two different approaches have been …