Cytotoxicity and Effects on Cell Viability of Nickel Nanowires

Handle URI:
http://hdl.handle.net/10754/293350
Title:
Cytotoxicity and Effects on Cell Viability of Nickel Nanowires
Authors:
Rodriguez, Jose E.
Abstract:
Recently, magnetic nanoparticles are finding an increased use in biomedical applications and research. Nanobeads are widely used for cell separation, biosensing and cancer therapy, among others. Due to their properties, nanowires (NWs) are gaining ground for similar applications and, as with all biomaterials, their cytotoxicity is an important factor to be considered before conducting biological studies with them. In this work, the cytotoxic effects of nickel NWs (Ni NWs) were investigated in terms of cell viability and damage to the cellular membrane. Ni NWs with an average diameter of 30-34 nm were prepared by electrodeposition in nanoporous alumina templates. The templates were obtained by a two-step anodization process with oxalic acid on an aluminum substrate. Characterization of NWs was done using X-Ray diffraction (XRD) and energy dispersive X-Ray analysis (EDAX), whereas their morphology was observed with scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Cell viability studies were carried out on human colorectal carcinoma cells HCT 116 by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) cell proliferation colorimetric assay, whereas the lactate dehydrogenase (LDH) homogenous membrane fluorimetric assay was used to measure the degree of cell membrane rupture. The density of cell seeding was calculated to obtain a specific cell number and confluency before treatment with NWs. Optical readings of the cell-reduced MTT products were measured at 570 nm, whereas fluorescent LDH membrane leakage was recorded with an excitation wavelength of 525 nm and an emission wavelength of 580 - 640 nm. The effects of NW length, cell exposure time, as well as NW:cell ratio, were evaluated through both cytotoxic assays. The results show that cell viability due to Ni NWs is affected depending on both exposure time and NW number. On the other hand, membrane rupture and leakage was only significant at later exposure times. Both cytotoxic assessment assays showed an earlier cytotoxic effect in case of shorter NWs, with longer ones having a more marked toxicity, albeit with a delay in time. These findings demonstrate that different levels of biocompatibility can be obtained with specific doses and properties of Ni NWs and can serve as guideline for future experiments.
Advisors:
Ravasi, Timothy ( 0000-0002-9950-465X )
Committee Member:
Kosel, Jürgen ( 0000-0002-8998-8275 ) ; Merzaban, Jasmeen ( 0000-0002-7276-2907 )
KAUST Department:
Physical Sciences and Engineering (PSE) Division
Program:
Chemical and Biological Engineering
Issue Date:
May-2013
Type:
Thesis
Appears in Collections:
Theses; Physical Sciences and Engineering (PSE) Division; Chemical and Biological Engineering Program

Full metadata record

DC FieldValue Language
dc.contributor.advisorRavasi, Timothyen
dc.contributor.authorRodriguez, Jose E.en
dc.date.accessioned2013-06-03T18:31:57Z-
dc.date.available2013-06-03T18:31:57Z-
dc.date.issued2013-05en
dc.identifier.urihttp://hdl.handle.net/10754/293350en
dc.description.abstractRecently, magnetic nanoparticles are finding an increased use in biomedical applications and research. Nanobeads are widely used for cell separation, biosensing and cancer therapy, among others. Due to their properties, nanowires (NWs) are gaining ground for similar applications and, as with all biomaterials, their cytotoxicity is an important factor to be considered before conducting biological studies with them. In this work, the cytotoxic effects of nickel NWs (Ni NWs) were investigated in terms of cell viability and damage to the cellular membrane. Ni NWs with an average diameter of 30-34 nm were prepared by electrodeposition in nanoporous alumina templates. The templates were obtained by a two-step anodization process with oxalic acid on an aluminum substrate. Characterization of NWs was done using X-Ray diffraction (XRD) and energy dispersive X-Ray analysis (EDAX), whereas their morphology was observed with scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Cell viability studies were carried out on human colorectal carcinoma cells HCT 116 by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) cell proliferation colorimetric assay, whereas the lactate dehydrogenase (LDH) homogenous membrane fluorimetric assay was used to measure the degree of cell membrane rupture. The density of cell seeding was calculated to obtain a specific cell number and confluency before treatment with NWs. Optical readings of the cell-reduced MTT products were measured at 570 nm, whereas fluorescent LDH membrane leakage was recorded with an excitation wavelength of 525 nm and an emission wavelength of 580 - 640 nm. The effects of NW length, cell exposure time, as well as NW:cell ratio, were evaluated through both cytotoxic assays. The results show that cell viability due to Ni NWs is affected depending on both exposure time and NW number. On the other hand, membrane rupture and leakage was only significant at later exposure times. Both cytotoxic assessment assays showed an earlier cytotoxic effect in case of shorter NWs, with longer ones having a more marked toxicity, albeit with a delay in time. These findings demonstrate that different levels of biocompatibility can be obtained with specific doses and properties of Ni NWs and can serve as guideline for future experiments.en
dc.language.isoenen
dc.subjectCytotoxicityen
dc.subjectNickel Nanowiresen
dc.subjectCell Viabilityen
dc.subjectMTT Assayen
dc.subjectLactate Dehydrogenaseen
dc.subjectNanofabricationen
dc.titleCytotoxicity and Effects on Cell Viability of Nickel Nanowiresen
dc.typeThesisen
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
thesis.degree.grantorKing Abdullah University of Science and Technologyen_GB
dc.contributor.committeememberKosel, Jürgenen
dc.contributor.committeememberMerzaban, Jasmeenen
thesis.degree.disciplineChemical and Biological Engineeringen
thesis.degree.nameMaster of Scienceen
dc.person.id118450en
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