Matching Items (3)
Filtering by
- All Subjects: chemical engineering
Description
Cellular models have been the backbone of models for drug therapeutics, discovery, or diagnostics, and for modeling a tumor microenvironment to understand the proliferation, migration, invasion, dormancy, angiogenesis, Conventional two-dimensional (2D) cell culture models are used because of the cost-effectiveness compared to animal models. But these models fail to mimic the cellular phenotype of a three-dimensional (3D) microenvironment. As a result, it is important to develop a 3D model that predicts cellular behaviors and their interaction with neighboring cells and extracellular matrix (ECM) in a more realistic setting. Various 3D cell culture methods have been employed to generate spheroids, in vitro, but most of these platforms face drawbacks such as spheroid size heterogeneity, low yield, use of specialized instruments etc. The hydrogel platform mentioned here was able to solve all the previous problems and can create a novel 3D tumor microenvironment. This thesis is focused on developing an in-vitro 3D model which can modulate the tumor microenvironment consisting of cancer cells and macrophages and how the Amikagel platform modulated the macrophage phenotype is discussed in detail here. This platform can be an ideal platform for macrophage phenotype modulation.
ContributorsChowdhury, Trishita (Author) / Rege, Kaushal (Thesis advisor) / Acharya, Abhinav (Committee member) / Khalifehzadeh, Layla (Committee member) / Arizona State University (Publisher)
Created2023
Description
Tissue approximation and repair have been performed with sutures and staples for centuries, but these means are inherently traumatic. Tissue repair using laser-responsive nanomaterials can lead to rapid tissue sealing and repair and is an attractive alternative to existing clinical methods. Laser tissue welding is a sutureless technique for sealing incised or wounded tissue, where chromophores convert laser light to heat to induce in tissue sealing. Introducing chromophores that absorb near-infrared light creates differential laser absorption and allows for laser wavelengths that minimizes tissue damage.
In this work, plasmonic nanocomposites have been synthesized and used in laser tissue welding for ruptured porcine intestine ex vivo and incised murine skin in vivo. These laser-responsive nanocomposites improved tissue strength and healing, respectively. Additionally, a spatiotemporal model has been developed for laser tissue welding of porcine and mouse cadaver intestine sections using near-infrared laser irradiation. This mathematical model can be employed to identify optimal conditions for minimizing healthy cell death while still achieving a strong seal of the ruptured tissue using laser welding. Finally, in a model of surgical site infection, laser-responsive nanomaterials were shown to be efficacious in inhibiting bacterial growth. By incorporating an anti-microbial functionality to laser-responsive nanocomposites, these materials will serve as a treatment modality in sealing tissue, healing tissue, and protecting tissue in surgery.
In this work, plasmonic nanocomposites have been synthesized and used in laser tissue welding for ruptured porcine intestine ex vivo and incised murine skin in vivo. These laser-responsive nanocomposites improved tissue strength and healing, respectively. Additionally, a spatiotemporal model has been developed for laser tissue welding of porcine and mouse cadaver intestine sections using near-infrared laser irradiation. This mathematical model can be employed to identify optimal conditions for minimizing healthy cell death while still achieving a strong seal of the ruptured tissue using laser welding. Finally, in a model of surgical site infection, laser-responsive nanomaterials were shown to be efficacious in inhibiting bacterial growth. By incorporating an anti-microbial functionality to laser-responsive nanocomposites, these materials will serve as a treatment modality in sealing tissue, healing tissue, and protecting tissue in surgery.
ContributorsUrie, Russell Ricks (Author) / Rege, Kaushal (Thesis advisor) / Acharya, Abhinav (Committee member) / DeNardo, Dale (Committee member) / Holloway, Julianne (Committee member) / Thomas, Marylaura (Committee member) / Arizona State University (Publisher)
Created2019
Description
Abnormally low or high blood iron levels are common health conditions worldwide and can seriously affect an individual’s overall well-being. A low-cost point-of-care technology that measures blood iron markers with a goal of both preventing and treating iron-related disorders represents a significant advancement in medical care delivery systems. Methods: A novel assay equipped with an accurate, storable, and robust dry sensor strip, as well as a smartphone mount and (iPhone) app is used to measure total iron in human serum. The sensor strip has a vertical flow design and is based on an optimized chemical reaction. The reaction strips iron ions from blood-transport proteins, reduces Fe(III) to Fe(II), and chelates Fe(II) with ferene, with the change indicated by a blue color on the strip. The smartphone mount is robust and controls the light source of the color reading App, which is calibrated to obtain output iron concentration results. The real serum samples are then used to assess iron concentrations from the new assay and validated through intra-laboratory and inter-laboratory experiments. The intra-laboratory validation uses an optimized iron detection assay with multi-well plate spectrophotometry. The inter-laboratory validation method is performed in a commercial testing facility (LabCorp). Results: The novel assay with the dry sensor strip and smartphone mount, and App is seen to be sensitive to iron detection with a dynamic range of 50 - 300 µg/dL, sensitivity of 0.00049 µg/dL, coefficient of variation (CV) of 10.5%, and an estimated detection limit of ~15 µg/dL These analytical specifications are useful for predicting iron deficiency and overloads. The optimized reference method has a sensitivity of 0.00093 µg/dL and CV of 2.2%. The correlation of serum iron concentrations (N=20) between the optimized reference method and the novel assay renders a slope of 0.95, and a regression coefficient of 0.98, suggesting that the new assay is accurate. Lastly, a spectrophotometric study of the iron detection reaction kinetics is seen to reveal the reaction order for iron and chelating agent. Conclusion: The new assay is able to provide accurate results in intra- and inter- laboratory validations and has promising features of both mobility and low-cost.
ContributorsSerhan, Michael (Author) / Forzani, Erica (Thesis advisor) / Raupp, Gregory (Committee member) / Acharya, Abhinav (Committee member) / Hu, Tony (Committee member) / Smith, Barbara (Committee member) / Arizona State University (Publisher)
Created2020