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dc.contributor.advisorAnderson, Diana
dc.contributor.advisorNajafzadeh, Mojgan
dc.contributor.authorAmadi, Emmanuel E.
dc.date.accessioned2021-12-15T15:29:21Z
dc.date.available2021-12-15T15:29:21Z
dc.date.issued2019
dc.identifier.urihttp://hdl.handle.net/10454/18685
dc.description.abstractFor the past few decades, the popularity of graphene oxide (GO) nanomaterials (NMs) has increased exceedingly due to their biomedical applications in drug delivery of anti-cancer drugs. Their unique physicochemical properties such as high surface area and good surface chemistry with unbound surface functional groups (e.g. hydroxyl - OH, carboxyl /ketone C=O, epoxy/alkoxy C-O, aromatic group C=C, etc) which enable covalent bonding with organic molecules (e.g. RNA, DNA) make GO NMs as excellent candidates in drug delivery nanocarriers. Despite the overwhelming biomedical applications, there are concerns about their genotoxicity on human DNA. Published genotoxicity studies on GO NMs were performed using non-commercial GO with 2-3 layers of GO sheets, synthesized in various laboratories with the potential for inter-laboratory variabilities. However, what has not been studied before is the effects of the commercial GO (15-20 sheets; 4-10% edge-oxidized; 1 mg/mL) in vitro on DNA damage in human whole blood and peripheral blood lymphocytes (PBL) from real-life patients diagnosed with chronic pulmonary diseases [asthma, chronic obstructive pulmonary disease (COPD), and lung cancer], and genotoxic endpoints compared with those from healthy control individuals to determine whether there are any differences in GO sensitivity. Thus, in the present study, we had characterized GO NMs using Zetasizer Nano for Dynamic Light Scattering (DLS) and zeta potential (ZP) in the aqueous solution, and electron microscopy using the Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM) in the dry state, respectively. Cytotoxicity studies were conducted on human PBL from healthy individuals and patients (asthma, COPD, and lung cancer) using the Methylthiazolyldiphenyl-tetrazolium bromide (MTT) and Neutral Red Uptake (NRU) assays, respectively. The genotoxicity (DNA damage) and cytogenetic effects (chromosome aberration parameters) induced by GO NMs on human whole blood from healthy individuals and patients were studied using the Alkaline Comet Assay and Cytokinesis-blocked Micronucleus (CBMN) assay, respectively. Our results showed concentration-dependent increases in cytotoxicity, genotoxicity, and chromosome aberrations, with blood samples from COPD and lung cancer patients being more sensitive to DNA damage insults compared with asthma patients and healthy control individuals. Furthermore, the relative gene and protein expressions of TP53, CDKN1A/p21, and BCL-2 relative to GAPDH on human PBL were studied using the Reverse Transcription Quantitative Polymerase Chain Reaction (RT-qPCR) and Western Blot techniques, respectively. Our results have shown altered gene and protein expression levels. Specifically, GO-induced cytotoxicity, genotoxicity, and micronuclei aberrations were associated with TP53 upregulation - a biomarker of DNA damage - in both patients and healthy individuals. These effects show that GO NMs have promising roles in drug delivery applications when formulated to deliver drug payload to COPD and cancer cells. However, the fact that cytotoxicity, genotoxicity, chromosome instability, and gene/protein expressions - biomarkers of cancer risk - were observed in healthy individuals are of concern to public health, especially in occupational exposures at micro levels at the workplace.en_US
dc.language.isoenen_US
dc.rights<a rel="license" href="http://creativecommons.org/licenses/by-nc-nd/3.0/"><img alt="Creative Commons License" style="border-width:0" src="http://i.creativecommons.org/l/by-nc-nd/3.0/88x31.png" /></a><br />The University of Bradford theses are licenced under a <a rel="license" href="http://creativecommons.org/licenses/by-nc-nd/3.0/">Creative Commons Licence</a>.eng
dc.subjectGraphene oxideen_US
dc.subjectHuman whole blooden_US
dc.subjectPeripheral blood lymphocytesen_US
dc.subjectAsthmaen_US
dc.subjectLung canceren_US
dc.subjectComet assayen_US
dc.subjectMicronucleus assayen_US
dc.subjectWestern Bloten_US
dc.subjectRT-qPCRen_US
dc.subjectNanomaterialsen_US
dc.subjectChronic obstructive pulmonary disease (COPD)en_US
dc.titleEffects of Graphene Oxide in vitro on DNA Damage in Human Whole Blood and Peripheral Blood Lymphocytes from Healthy individuals and Pulmonary Disease Patients: Asthma, COPD, and Lung Canceren_US
dc.type.qualificationleveldoctoralen_US
dc.publisher.institutionUniversity of Bradfordeng
dc.publisher.departmentFaculty of Life Sciencesen_US
dc.typeThesiseng
dc.type.qualificationnamePhDen_US
dc.date.awarded2019
refterms.dateFOA2021-12-15T15:29:21Z


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