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Studies On The Size And Non-Planarity Of Aromatic Stacking Moiety On Conformation Selectivity And Thermal Stabilization Of G-Quadruplexes, Mandeep Singh

University of the Pacific Theses and Dissertations

Targeting DNA has the advantage over proteins for cancer remediation because of the fewer copies of the ligands required for the desired therapeutic effect. Traditionally, covalent DNA binders like alkylating agents have been used to induce genetic instability through the formation of DNA lesions and strand breaks, leading to cellular apoptosis. The primary drawback of this treatment is the non-specific binding that affects both cancerous and non-cancerous cells. G-quadruplexes are the DNA secondary structures that are present in abundance near the promoter regions of the oncogenes and are involved in the regulation of their activities. A ligand-mediated stabilization of G-quadruplexes …

Tools To Evaluate Nanodiamond-Mediated Delivery Of Tiopronin For Cataract Prevention, Justin Beltz

Doctoral Dissertations

”There is a growing demand for non-surgical means of cataract treatment. This dissertation presents three bodies of work that reflect the early-stage development of eye drop formulations aimed at delaying cataract progression. These formulations consist of the antioxidant 2-mercaptopropionylglycine (MPG) loaded onto nanodiamond particles.

Cataractogenesis is linked to oxidative damage to lens proteins. To investigate the potential of MPG for protection against oxidative damage, A549 cells were incubated in 0.6 mM tert-butylhydroperoxide (tBHP). Cells exposed to tBHP without MPG exhibited elevated levels of reactive oxygen species, which led to the depletion of the vital antioxidant glutathione and, ultimately, apoptosis. Co-administration …

Electrospinning Piezoelectric Fibers For Biocompatible Devices, Bahareh Azimi, Mario Milazzo, Andrea Lazzeri, Stefano Berrettini, M. Jasim Uddin, Zhao Qin, Markus J. Buehler, Serena Danti

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

The field of nanotechnology has been gaining great success due to its potential in developing new generations of nanoscale materials with unprecedented properties and enhanced biological responses. This is particularly exciting using nanofibers, as their mechanical and topographic characteristics can approach those found in naturally occurring biological materials. Electrospinning is a key technique to manufacture ultrafine fibers and fiber meshes with multifunctional features, such as piezoelectricity, to be available on a smaller length scale, thus comparable to subcellular scale, which makes their use increasingly appealing for biomedical applications. These include biocompatible fiber-based devices as smart scaffolds, biosensors, energy harvesters, and …

Lanthanide-Doped Lanthanum Hafnate Nanoparticles As Multicolor Phosphors For Warm White Lighting And Scintillators, Santosh K. Gupta, Jose P. Zuniga, Maya Abdou, Melonie P. Thomas, Manisha De Alwis Goonatilleke, Beth S. Guiton, Yuanbing Mao

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Designing luminescent materials especially nanomaterials with multifunctional applications is highly challenging and demanding. In this work, we explored pyrochlore La2Hf2O7 nanoparticles (NPs) singly and triply codoped with Eu3+, Tb3+ and Dy3+. Under both ultraviolet and X-ray irradiations, the La2Hf2O7 NPs singly doped with Eu3+, Tb3+ and Dy3+ displayed red, green and yellowish-blue emission, respectively. The concentration quenching study revealed a non-radiative energy transfer in Eu3+ doped La2Hf2O7 NPs, which takes place via dipole-quadrupole mechanism. On the other hand, a dipole-dipole interaction prevails in Tb3+ and Dy3+ doped La2Hf2O7 NPs. Lifetime spectroscopy reveals the stabilization of Eu3+ and Dy3+ ions at …

Multimodal Vibrational Studies Of Drug Uptake In Vitro: Is The Whole Greater Than The Sum Of Their Parts?, David Perezguaita, Karolina Chrabaszcz, Kamilla Malek, Hugh Byrne

Articles

Herein, we investigated the use of multimodal Raman and infrared (IR) spectroscopic microscopy for the elucidation of drug uptake and subsequent cellular responses. Firstly, we compared different methods for the analysis of the combined data. Secondly, we evaluated whether the combined analysis provided enough benefits to justify the fusion of the data. A459 cells inoculated with doxorubicin (DOX) at different times were fixed and analysed using each technique. Raman spectroscopy provided high sensitivity to DOX and enabled an accurate estimation of the drug uptake at each time point, whereas IR provided a better insight into the resultant changes in the …

Quantification Of Low-Content Encapsulated Active Cosmetic Ingredients In Complex Semi-Solid Formulations By Means Of Attenuated Total Reflectance-Infrared Spectroscopy, Franck Bonnier, Lynda Miloudi, Sandra Henry, Dominique Bertrand, Clovis Tauber, Xavier Perse, Florent Yvergnaux, Hugh Byrne, Igor Chourpa, Emilie Munnier

Articles

Attenuated total reflectance-infrared (ATR-IR) spectroscopy is a robust tool for molecular characterisation of matter. Applied to semi-solid formulations, it enables rapid and reliable data collection without pre-analytical requirements. Based on nano-encapsulated Omegalight®, a skin-lightening active cosmetic ingredient (ACI), incorporated in a hydrogel, it is first demonstrated that, despite the high water content and the chemical complexity of the samples (i.e. number of ingredients), the spectral features of the ACI can be detected and monitored. Secondly, with a total of 105 samples divided into a training set (n = 60) and an unknown set (n = 45) covering a …

Raman Mapping Coupled To Self Modelling Mcr-Als Analysis To Estimate Active Cosmetic Ingredient Penetration Profile In Skin, Aline Stella, Franck Bonnier, Ali Tfayli, Florent Yvergnaux, Hugh Byrne, Igor Chourpa, Emilie Munnier, Clovis Tauber

Articles

Confocal Raman mapping (CRM) is a powerful, label free, non-destructive tool, enabling molecular characterization of human skin with applications in the dermo-cosmetic field. Coupling CRM to multivariate analysis can be used to monitor the penetration and permeation of active cosmetic ingredients (ACI) after topical application. It is presently illustrated how multivariate curve resolution alternating least squares (MCR-ALS) can be applied to detect and semi-quantitatively describe the diffusion profile of Delipidol, a commercially available slimming ACI, from Raman spectral maps. Although the analysis outcome can be critically dependent on the a priori selection of the number of regression components, it is …

Exploiting Fourier Transform Infrared And Raman Microspectroscopies On Cancer Stem Cells From Oral Squamous Cells Carcinoma: New Evidence Of Acquired Csplatin Chemoresistance, Valentina Notarstefano, Simona Sabbatini, Chiaro Pro, Alessia Belloni, Giulia Orilisi, Corrado Rubini, Hugh Byrne, Lisa Vaccari, Elisabetta Giorgini

Articles

Oral Squamous Cells Carcinoma (OSCC) is characterised by the risk of recurrence and the onset of a refractoriness response to chemotherapy drugs. These phenomena have been recently related to a subpopulation of Cancer Stem Cells (CSCs), which have either an innate or acquired drug resistance, triggered by chemotherapy treatments. In this light, to precisely target chemotherapy regimens, it is essential to improve knowledge on CSCs, with a particular focus on their molecular features. In this work, a subpopulation of CSCs, isolated by tumour sphere formation from primary OSCC cells, were treated with cisplatin for 16, 24 and 48 hours and …

Synthesis And Design Of Novel Polymer Grafted Nanoparticles Relevant To Drug Delivery Vehicles For Biomedical Application, Maan Abduldiyem Hassan Al-Ali

Theses and Dissertations

The modification of inorganic nanoparticles with organic polymer chains has become a significant field of study for the engineering of advanced nanocomposite materials. This dissertation presents the design, synthesis, and characterization of novel polymer grafted silica nanoparticles as new strategies to combat bacterial resistance. Described herein is the synthesis of monomers that have been graft polymerized onto silica nanoparticles that can be used as a delivery drug vehicle for biomedical applications. The polymerization of these monomers was performed via reversible addition-fragmentation chain transfer (RAFT) polymerization. The molecular design of the RAFT agents that are attached to the surfaces of the …

Metal Ions Impact On Shewanella Oneidensis Mr-1 Adhesion To Ito Electrode And The Enhancement Of Current Output, Aisha Awad Alshahrani

Dissertations

The goal of this study is to enhance the efficiency of bacterial extracellular electron transfer (EET) in Shewanella oneidensis MR-1 by enhancing adhesion to the electrode's surface. Our results clearly show a major difference in the attachment and behavior of Shewanella oneidensis MR-1 for Ca2+, Pb2+, Cd2+, and Mg2+, compared to the control. the final microbial coverage, as measured by confocal microscopy and cathodic peak charge in cyclic voltammetry (Qpc), increases with increasing metal ion concentrations. We found the cells attached to the electrode increased more with the addition of metal ion concentrations in the following order of metals: Ca2+ …

Optimization Of Microbial Fuel Cells, Norberto M. Gonzalez

Dissertations

Optimization of microbial fuel cells is investigated by utilizing Shewanella oneidensis as a model microorganism. the microbe's ability to grow and use glucose as a carbon source is explored under varying oxygen environments through an offline PMP derivatization method and HPLC analysis. Shewanella growth and glucose utilization is enhanced under aerobic environments; however, under microaerobic environments the addition of ferric iron results in a faster exponential growth initialization. a flavin mononucleotide modified indium tin oxide electrode is prepared and characterized for its usefulness in microbial fuel cells by controlled potential electrolysis, cyclic voltammetry, and electrochemical impedance spectroscopy studies. the electrode …

Electron Transfer Of Shewanella Oneidensis Mr-1 At Clay-Modified Ito Electrode, Reem Faez Alshehri

Dissertations

Various strategies have been established to enhance the extracellular electron transfer and energy output capability of microbial fuel cells, with the majority being aimed at anode modification. The anode has a significant impact on the electricity generation performance of MFCs because it is in direct contact with the microorganisms. The materials of the anode should be favorable for the bacterial cell and capable to facilitate the electron transfer. Developing of an electrode using low-cost and effective materials assists to enhance the bacterial cell attachment and extracellular electron transfer. This provides a significant improvement in MFC performance. In this study, clay …

Synthesis And Evaluation Of Nebraska Red Derivatives For Protein Labeling Studies, Lauren Lesiak

Honors Program: Senior Projects (Public)

G protein-coupled receptors (GPCRs) play a vital role in cell signaling, and imaging the internalization of these proteins will allow for better understand of protein trafficking within the cell, as well as identification of potential drug targets. However, there is a need for further development of fluorescent protein labels that are able to effectively monitor GPCR internalization in the near-infrared (NIR) range. We recently described a series of NIR fluorophores in which a phosphinate functionality is inserted at the bridging position of the xanthene scaffold, called the Nebraska Red (NR) dye series. These dyes are attractive reagents for the imaging …

Surface-Enhanced Raman Scattering For Enantiomeric Discrimination, Thanyada Sukmanee

Chulalongkorn University Theses and Dissertations (Chula ETD)

Surface-enhanced Raman scattering (SERS) substrates with intended surface modification were developed for enantiomeric analysis by taking the consideration of asymmetric electric field and molecular interaction between a probe molecule and enantiomeric analyte. In the first study, discrimination between enantiomers is achieved by performing tip-enhanced Raman scattering using a silver tip which is chemically modified by an achiral para-mercaptopyridine (pMPY) probe molecule. The different relative intensities of the pMPY spectra were obtained when three pairs of enantiomers containing hydroxy and/or amino groups were used as analytes. Enantiomeric discrimination can be attained by the asymmetric electric field of the tip apex co-existed …

Electrospun Polyacrylonitrile/Graphene Oxide Nanofibers As Sorbent For Solid Phase Extraction Of Epichlorohydrin In Water, Chotitas Sribun

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this study, electrospun nanofibers of polyacrylonitrile functionalized with graphene oxide (PAN/GO) were fabricated and applied as a sorbent in solid phase extraction in a disk format (SPE disk). Graphene oxide were synthesized by chemical oxidation of graphite powder via Hummers and Tour methods and were characterized by X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). For electrospun PAN/GO nanofibers, the average diameters of fibers ranged from 117-147 nm and the surface area of PAN and PAN/GO nanofibers were ranged from 7.77-13.40 m2/g. Then, the PAN/GO nanofibers were assembled in a SPE disk format and …

Development Of Polymeric Niosomes Containing Oxyresveratrol For Skin Care Products, Jirawut Jaimun

Chulalongkorn University Theses and Dissertations (Chula ETD)

Designing delivery systems to improve active ingredient (AI) efficiencies have increased incredible interests in recent years. In this study, a vesicular system has been developed using thin film hydration method with modifications. Niosomes formed from sorbitan monoesters (SpanTM) with cholesterol molar ratios of 0, 0.5, 1 and 1.5 were prepared with varying AI amount 10-50 mg and was hydrated by hyaluronan solution. Oxyresveratrol was separated from the heartwoods of Artocarpus lacucha. This AI has been broadly utilized to restrain enzyme tyrosinase; however, it possesses low stability against heat and light. Encapsulation utilizing niosome or polymeric niosome as a delivery system …

Regenerated Amorphous Cellulose From Pineapple Leaf Fibers Via Sulfuric Acid Treatment, Gisma Coraima Asmarani

Chulalongkorn University Theses and Dissertations (Chula ETD)

Pineapple leaf fiber (PALF) is an agricultural residue available abundantly in Thailand as a renewable resource with high cellulose content. In this research, a simple process using sulfuric acid (H2SO4) treatment has been developed to produce three types of cellulosic products from PALF, which are regenerated amorphous (RAC), microcrystalline (MCC), and nanocrystalline (NCC) cellulose. H2SO4 acid treatment has been done in 25% and 50% (v/v) H2SO4 under three different temperatures (-20, 30, and 50 ºC). In 25% (v/v) H2SO4, various MCC lengths (about 29.57 ± 9.99 to 106.40 ± 61.10 μm) were produced from different temperatures. Different temperatures in this …

Electrocoagulation In Two Phase Separation For Manipulation Of Volatile Compound Profiles In Perfumes, Isaya Thaveesangsakulthai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Electrocoagulation (EC) approach employing two aluminium electrodes and a two phase medium of aqueous solution of NaCl and hexane (2-phase-EC) was developed. The approach enabled electrochemical treatment of odor active compounds in perfume extract. The samples before and after 2-phase-EC at cathode, anode and between the two electrodes left for equilibrium after the treatment were analyzed by using solid phase micro extraction (SPME) and gas chromatography hyphenated with mass spectrometry (GC-MS). This allowed identification of volatile compounds in each sample based on comparison with MS and retention index database. After the treatment, the perfume smells were fresher, sweeter and more …

Development Of Cellulose As Substrates For Adsorbents And Sensors, Jadetapong Klahan

Chulalongkorn University Theses and Dissertations (Chula ETD)

This thesis deals with two parts of development of novel sensors based on cellulose substrate platform. The first part is the development of fluorescence sensors and adsorbents for metal ions using bacterial cellulose as the platform. The second part is the development of colorimetric sensors for smartphone detection of oil marker using filter paper as the platform. In the first part, bacterial cellulose (BC) has several advantageous properties over plant cellulose such as high purity, high surface area, high porosity, and high water-holding capacity due to its three-dimensional network of nanofibrils structure, that make BC appealing for applications related to …

Tuning Of Metal Ion Selectivity By Varying Number Of Coordinating Atoms In Quinoline-Derived Fluorescent Sensors, Jutawat Hojitsiriyanont

Chulalongkorn University Theses and Dissertations (Chula ETD)

Both Cd2+ and Zn2+ are metal ions in group 12 elements with very different toxicities but similar binding properties to most organic and biological ligands. In this work, a series of quinoline derivatives were synthesized and studied with an aim for Cd2+ selective turn-on fluorescent sensors. The structures of the compounds were designed to systematically evaluate the effects of amino protons, number of N-coordinating atoms, quinoline/picoline moieties and substituents on the sensing properties. The association constants of all synthesized ligands were studied by UV-vis absorption titration in aqueous solution. The results revealed that the ligands having 6- and 4- donor …

Synthesis And Encapsulation Of 1,3,5-Triazine Derivatives As Anticancer Agent, Monnaya Chalermnon

Chulalongkorn University Theses and Dissertations (Chula ETD)

The 1,3,5-triazine scaffold is known for its versatile biological activities especially as an anticancer agent, but a limitation of 1,3,5-triazine is the ability to reach cancer cells thus affecting its anticancer potency. In this work, the anticancer activity of twelve 1,3,5-triazine derivatives was evaluated against two colon cancer cell lines along with an investigation of a drug delivery system (DDS) using calcium citrate nanoparticles (CaCit NPs). Results from the biological evaluation showed that there was a variation in the anticancer activity of 1,3,5-triazine derivatives which some of them exhibited comparable activity to the reference drug cisplatin. Compound 2a and 3d …

Fluorescence Sensors From Pyreno[4,5-D]Imidazole Derivatives, Nichapa Chanawungmuang

Chulalongkorn University Theses and Dissertations (Chula ETD)

Herein, The five fluorescent probes (P1, P2, P3, P4 and P5) based on pyreno[4,5-d]imidazole were successfully prepared in two steps from pyrene in 26 – 40% overall yields. After that, all of the compounds were studied the photophysical properties and selectivity for sensing metal ions. The results showed compound P5 was not selective to metal ions while the others (P1, P2, P3 and P4) were selective to detection of trivalent metal ions such as Bi3+, Al3+, Cr3+ and Fe3+ in CH3CN. However, only compound P2 with 2-hydroxyl phenyl substituent on imidazole ring formed complexation reaction selectively towards bismuth (III) ions …

Bacterial Cellulose Composites For Target Analyte Preconcentration In Analytical Applications, Panlop Lormaneenopparat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Bacterial cellulose (BC) is a well-known natural material with desirable properties including biocompatibility, biodegradability, hydrophilicity, high mechanical strength, high porosity, and broad chemically modifiable capacity. Herein, we incorporate carboxymethyl cellulose (CMC) in BC hydrogel to improve the swelling property and prevent collapsing of 3D bacterial cellulose network upon drying. In addition, gold nanoparticles (AuNPs) were successfully embedded within the BC/CMC composite using in situ chemical reduction. Moreover, AuNPs were uniformly distributed in BC/CMC matrix with a diameter of approximately 13 nm. The freeze-dried BC/CMC/AuNPs composite was subsequently used for adsorption of targeted analytes for laser desorption/ionization mass spectrometry. In particular, …

Design And Synthesis Of Modified Chitosan/Collagen Coated-Gold Nanoparticles As A Carrier For Anticancer And Antiinflammatory Agents, Naruthai Hongsa

Chulalongkorn University Theses and Dissertations (Chula ETD)

The proposes of this research are to improve the delivery efficiency of AuNPs. One of the problems with drug loading and drug degradation, the drug was loaded onto the surface of the gold particles, adheres to the outer of the surface, which was easy to decompose in the body. In this work, we have developed the coated AuNPs by modified chitosan (Bi-QCS), which the Biotin-Quat188-AuNPs@collagen (Bi-QCS-AuNPS@collagen) was designed as follow: (i) collagen was used as a reducing agent and a stabilizing agent in the AuNPs@collagen, while (ii) modified chitosan (positive charge polymer) was coated on the outer layer, which modified …

Pyrrolidinyl Peptide Nucleic Acid Probe Capable Of Crosslinking With Dna, Penthip Muangkaew

Chulalongkorn University Theses and Dissertations (Chula ETD)

DNA interstrand cross-linking (ICL) is a phenomenon in which two strands of the DNA (most often as part of the same DNA duplex) bind together via a covalent bond. This process prevents the DNA strand dissociation, which is essential for its biological functions, and thus is extremely damaging to cells. To overcome the problem of non-specificity associated with general DNA cross-linking agents, a cross-linkable probe in which the reactive group is placed on the probe that can specifically recognize part of the DNA target. The strong binding affinity and biological stability of the pyrrolidinyl peptide nucleic acid (acpcPNA) inspired us …

Anti-Oxidant And Anti-Inflammatory Compounds From Magnolia Liliifera (L.) Baill. Flower And Dendrobium Signatum Rchb.F., Prajak Khumploy

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this study, a purification of the EtOAc crude extract of Dendrobium signatum Rchb.f. aerial parts was performed fifteen compounds (1-15) and the hexane crude extracts of Magnolia liliiferra (L.) Baill. were further isolated to accomplish three compounds (16-18). They yielded one new picrotoxane sesquiterpene, 7-hydroxydendroterpene B (2) and a new a-pyrone, (-)-6R-signatone (4), along with sixteen known compounds. These included dendroxine (1), crystallinin (3), dendrocandin B (5), dendrocandin I (6), 6''-de-O-methyldendrofindlaphenol A (7), p-hydroxyphenylethyl-p-coumarate (8), 3,4-dihydroxy-5,4'-dimethoxybibenzyl (9), 3-methoxy-5-[2-(4-methoxyphenyl) ethyl]phenol (10), 4,4'-dihydroxy-3,5-dimethoxybibenzyl (11), naringenin (12), (2S)-homoeridodictyol (13), (2S)-homohesperetin (14), (-)-syringaresinol (15), (+) sesamin (16), (+) fargesin (17) and (-) kobusin …

Tetrabromomethane-Mediated Desulfurization For Synthesis Of Isothiocyanates From Amines, Saharat Techapanalai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Isothiocyanate considered as an important building block for pharmaceutical industry. Traditional methods for preparation of isothiocyanate involved the desulfurization of dithiocarbamate salt from amine using oxidizing agent. Although those methods are efficient, however, all of them require the use of toxic reagent, strong oxidizing agent, multiple step synthesis, harsh condition and large amount of metal catalyst. Therefore, in this research, we develop two mild methods to synthesize isothiocyanates from amines using low toxic reagent. For the first process, we were able to demonstrate the use of photocatalyst, safranin O to convert dithiocarbamate salt of 4-bromoaniline into 4-brophenyl isothiocyanate in 48% …

Synthesis Of 5-Phenoxyprimaquine Derivatives And Their Tetraoxane Conjugates As Anti-Malarial Agents, Somruedee Jansongsaeng

Chulalongkorn University Theses and Dissertations (Chula ETD)

Currently, the development of the new anti-malarial drug for the treatment of the increasing drug-resistant strains of malaria was necessary. Therefore, this research was performed by synthesis and evaluation of their antimalarial activity for the development of primaquine which currently was used for anti-malarial drug. The substituents group on 5-phenoxyprimaquine derivatives which had the highest therapeutic index and less toxicity than primaquine were emphasized. The effect of substituted group at para position was studied. Three new derivatives with CN (7e), CF3 (7g), CONH2 (7h) substituents, and five known derivatives with OMe (7b), Br (7c), Cl (7d), F (7f) substituents and …

Anti-Proliferative Metabolites From The Root Of Calophyllum Inophyllum L., Syahadatain Nor Haerani

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study aimed to isolate secondary metabolites from the root of C. inophyllum L. and to evaluate their anti-proliferative activities against hepatocellular carcinoma and colorectal cancer cells. Chromatographic fractionation of the n-hexane and ethyl acetate crude extracts led to the isolation of two new (1 and 2) and twelve known xanthones (3-14). In addition, metabolites 4, 6 and 8 were isolated from the genus Calophyllum for the first time. All metabolites were evaluated for their anti-proliferative activity against Hep-G2 and HCT-116 cell lines. Metabolites 5 and 14 showed the most active metabolites against both cancer cells, as well as they …

Effect Of Dealumination And Desilication Of Beta Zeolite On Performance Of Nickel Catalysts In Hydroisomerization For Bio-Jet Fuel Production, Warodom Hunsiri

Chulalongkorn University Theses and Dissertations (Chula ETD)

-The Global aviation fuel consumption tends to increase. In recent years, the European Union has announced that fossil fuels jet fuel must be mixed with 10% biofuels in 2020. bio-jet fuel production has many processes such as biomass pyrolysis. or hydro-p