Digital Commons Network^™

Methods For Producing Graphene From Petroleum By-Products, Eva M. Deemer

Open Access Theses & Dissertations

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Complementary Charged Molecular Imprints Of West Nile Virus Antibodies, Julio Rincon

Open Access Theses & Dissertations

There is a significant demand for robust and stable receptor molecules that can mimic biological molecules, such as antibodies. Relying only on natural recognition molecules have greatly limited the uses and capabilities of many aspects of health sciences due to product expense and stability. This is especially important in medically underserved areas where the lack of resources and faulty or limited cold-chain makes antibody based diagnostics very difficult to implement.

With molecular imprinting, it is possible to recognize diseases with the added advantage of product stability, long term use, fast preparation and ease of scalability, all while being cost effective. …

Design And Regioselective Synthesis Of Fullerene Derivatives For Metal-Organic Hybrid Architectures, Catalina Suarez

Open Access Theses & Dissertations

In the last years different fullerene derivatives and endohedral fullerenes have been reported and their potential applications as electronic, magnetic, catalytic, biological and optical materials have been explored. In this work we describe the characterization of new endohedral fullerenes; the exohedral functionalization of fullerenes with organic addends or metal clusters and their application in metal-organic hybrid architectures.

We synthesized fullerene polymers with a variety of staircase linear architectures, zigzag polymers and a perfectly linear polymer using an hexakis-fullerene adduct with two 4,5-diazafluorene groups located at trans-1 positions, using Hg, Cd, Zn and33 Cu as the metal centers. Our results showed …

Synthesis Of New Fullerene Derivatives For Photovoltaic And Biological Applications, Edison Castro

Open Access Theses & Dissertations

Functionalized fullerenes exhibit improved solubility and different chemical and physical properties that allow applications in multiple fields such as photovoltaic and biological applications. Currently, perovskite solar cells (PSCs) are the most rapidly developing type of solar cells with certified efficiencies rising from 3.8% in 2009 to 22.1% in 2016. The good electron transporting and solution processable properties of most fullerene derivatives make them the most popular electron transporting materials (ETMs) in inverted perovskite solar cells (PSCs).

The work is reported in 11 chapters. We start with a fullerene overview followed by cleaver and elegant methodologies that allow the synThesis of …

Biofunctionalized Capillary Flow Channel Platform Integrated With 3d Nanostructured Matrix To Capture Circulating Tumor Cells, Shashwat Banerjee, Ganesh Khutale, Vrushali Khobragade, Narendra Kale, Milind Pore, Govind Chate, Archana Jalota-Badhwar, Manoj Dongare, Jayant Khandare

Articles

Circulating tumor cells (CTCs) from peripheral blood account genetic information for cancer diagnosis and overall disease monitoring. Analysis of “liquid biopsy” holds immense promise as it may lead to new approaches for cancer treatment. The study reports effective and continuous flow microchannel system for isolating CTCs using transferrin conjugated 3D matrix synthesized by crosslinking polyethylene glycol-Fe3O4 nanostructures for rapid and efficient capturing of CTCs. The platform provides option of using multiple microchannel units in series that can influence higher cell-capture efficiency due to increasing cell-substrate contact frequency. CTCs are captured with high efficiency even at low concentration of target cells …

Polymer Grafted Nanoparticles For Designed Interfaces In Polymer Nanocomposites, Mohammad Mohammadkhani

Theses and Dissertations

This dissertation presents the design, synthesis, and characterization of polymer nanocomposite interfaces and the property enhancement from this interface design. Through the use of reversible addition fragmentation chain transfer (RAFT) polymerization for the grafting of polymer chains to silica nanoparticles, the surface of silica nanoparticles can be manipulated to tune the properties of nanocomposites by controlling the interface between the particles and the polymer matrix.

In the first part of this work, compatibility of 15 nm silica nanoparticles grafted with different alkyl methacrylates with linear low density polyethylene was investigated. SI-RAFT polymerization of hexyl, lauryl, and stearyl methacrylate on silica …

Mild Hydrofunctionalizations Of Olefins Using More Cost-Effective Metal Catalysts, Alexander James Villani-Gale

Dissertations

The focus of this dissertation is the study of alkene hydroaylation reactions. In the first chapter, a review of the relevant literature concerning zinc- and iron-catalyzed hydroarylation of unsaturated bonds is presented. In chapter two, the development of a zinc-catalyzed hydroarylation of alkenes is presented, which is quickly followed by a detailed investigation into the probable mechanism. Chapter three discusses the development of an iron/silver-catalyzed arene prenylation reaction, followed by the development of an iron/zinc-catalyzed arene prenylation reaction. The final section of chapter three discusses the adaptation of the iron/zinc-catalyzed arene prenylation into an undergraduate organic teaching laboratory.

The Potential Of Atmospheric Air Cold Plasma For Control Of Bacterial Contaminants Relevant To Cereal Grain Production, Agata Los, Dana Ziuzina, Daniela Boehm, Patrick J. Cullen, Paula Bourke

Articles

The aim of this work was to investigate the efficacy of dielectric barrier discharge atmospheric cold plasma (DBD ACP) against bacteria associated with grains quality and safety. ACP inactivation efficacy was tested against biofilms formed by different strains of E. coli, Bacillus and Lactobacillus in grain model media and against B. atrophaeus endospores either in grain media or attached on abiotic surfaces. Effects were dependent on bacterial strain, media composition and mode of ACP exposure. ACP treatment for 5min reduced E. coli spp., B. subtilis and Lactobacillus spp. biofilms by >3 log10, whereas insignificant reductions were achieved for B. atrophaeus. …

พอลิแล็กทิกแอซิด/พอลิไวนิลแอลกอฮอล์/แกรฟีนนาโนคอมพอสิต, จาฬุพักต์ รัตนคช

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้มีวัตถุประสงค์เพื่อพัฒนาวิธีการเตรียมพอลิแล็กทิกแอซิด/พอลิไวนิลแอลกอฮอล์/แกรฟีนนาโนคอมพอสิต รวมถึงศึกษาอิทธิพลของการเติมอนุภาคแกรฟีนต่อสัณฐานวิทยา สมบัติเชิงกล สมบัติทางความร้อน และสมบัติการนำไฟฟ้าของวัสดุนาโนคอมพอสิตที่เตรียมได้ โดยเริ่มด้วยการสังเคราะห์แกรฟีนจากแกรไฟต์ด้วยวิธีของฮัมเมอร์ และใช้กรดแอลแอสคอร์บิกเป็นตัวรีดิวซ์ พิสูจน์เอกลักษณ์ของอนุภาคแกรฟีนที่เตรียมได้ด้วยเทคนิคอินฟราเรดสเปกโทรสโกปีและเทคนิคเอกซเรย์ดิฟแฟรกชัน จากนั้นเตรียมของผสมระหว่างพอลิไวนิลแอลกอฮอล์กับแกรฟีนที่ปริมาณต่าง ๆ ด้วยวิธีแช่เยือกแข็ง แล้วนำไปผสมกับพอลิแล็กทิกแอซิดด้วยเครื่องอัดรีดสกรูคู่และขึ้นรูปเป็นชิ้นงานด้วยกระบวนการอัดแบบ ศึกษาสัณฐานวิทยาเพื่อวิเคราะห์อันตรกิริยาของผสมระหว่างพอลิไวนิลแอลกอฮอล์กับแกรฟีนด้วยกล้องจุลทรรศน์แบบคอนโฟคอล และวิเคราะห์ภาคตัดขวางของชิ้นงานคอมพอสิตด้วยกล้องจุลทรรศน์อิเล็กตรอนแบบส่องกราด ผลการทดสอบสมบัติเชิงกล สมบัติทางความร้อน และสมบัติการนำไฟฟ้าของวัสดุนาโนคอมพอสิตที่เตรียมได้ พบว่าปริมาณผลึกลดลงเมื่อปริมาณแกรฟีนเพิ่มขึ้น แต่ไม่ส่งผลต่ออุณหภูมิกลาสทรานสิชัน อุณหภูมิหลอมเหลวผลึก และอุณหภูมิการเกิดผลึก อีกทั้งการเติมแกรฟีนที่มีการใช้พอลิไวนิลแอลกอฮอล์เป็นตัวพาลงในพอลิเมอร์เมทริกซ์ ทำให้ความทนแรงดึง และความยืดสูงสุด ณ จุดขาด มีแนวโน้มลดลงด้วย อย่างไรก็ดีการเติมแกรฟีนในปริมาณน้อย ๆ สามารถช่วยเพิ่มความทนแรงดึงได้เมื่อเปรียบเทียบกับงานวิจัยก่อนหน้าที่ไม่มีการเติมตัวพาหรือตัวช่วยเพิ่มการกระจายตัว นอกจากนี้พบว่าปริมาณแกรฟีนที่เพิ่มขึ้น ทำให้ค่าการนำไฟฟ้าของคอมพอสิตเมื่อเทียบกับพอลิแล็กทิกแอซิดบริสุทธิ์เพิ่มขึ้น คอมพอสิตที่พัฒนาขึ้นสามารถนำไปประยุกต์ในงานที่ต้องการสมบัติการต้านทานไฟฟ้าสถิตย์ได้

Catalytic Hydrogenation Of Carbon Dioxide For Hydrocarbon Synthesis, Nuttakorn Boreriboon

Chulalongkorn University Theses and Dissertations (Chula ETD)

Catalytic hydrogenation can turn CO2 into hydrocarbon fuel. The development of the catalysts for CO2 hydrogenation has become important since the catalysts are critical for selective production of more higher hydrocarbons for practical application. In this work, the titania supported monometallic and bimetallic Fe-M (M = Co and Cu) catalysts were synthesized and tested for CO2 hydrogenation at 573 K and 1.1 MPa. Among the monometallic catalysts (Fe, Co and Cu/TiO2), only Fe/TiO2 catalyst exhibited some selectivity to higher hydrocarbons, while Co/TiO2 and Cu/TiO2 catalysts were highly selective only to CH4 and CO, respectively. The addition of a small amount …

Hydrogen Rich Gas Production From Pyrolysis-Gasification Of Biomass With Combined Catalyst And Sorbent, Teerayut Bunma

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this work, the hydrogen production during biomass steam pyrolysis-gasification with a combined catalysts and sorbent (catalyst/sorbents) was studied in a drop tube two-stages fixed bed reactor. The catalyst/sorbents were prepared by an excess-solution impregnation method. A nickel oxide (NiO)/magnesium oxide (MgO)/calcium oxide(CaO) catalyst/sorbents containing 10 wt. % NiO, 5 wt. % MgO and 5 wt. % CaO on gamma alumina (γ-Al2O3) showed the best activity in sorption enhanced hydrogen production (SEHP) for the pyrolysis-gasification of sugarcane leaves. Besides, the highest H2 concentration and the lowest CO2 concentration were attained using the Mg5Ni10Ca5 catalyst/sorbents. Because Mg5Ni10Ca5 catalyst/sorbents provided the dominant …

Nanomaterial Sensors For Selective Detection Of Biothiol Compounds, Chiraporn Chaicham

Chulalongkorn University Theses and Dissertations (Chula ETD)

Novel nanomaterial sensors have been designed two different strategies of sensing approach. The first sensing system, the aggregation nanomicelles (TSC and TSD) were synthesized for GSH sensing based on disulfide-cleavaged trigger in the micelle. The result showed a large quenching fluorescent intensity around 587 nm and 528 nm corresponding to TSC and TSD, respectively, upon the addition of GSH in 2.5% DMSO/PBS at pH 6. Additionally, the benefit of TSD is utility for the distance-based fluorescence detection of 3D paper analytical device (3D-µPAD) for the detection of GSH. Apart from GQDs sensors base, we demonstrated the utility and board applicability …

Photocatalytic Conversion Of Glycerol To Dihydroxyacetone, Trin Jedsukontorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

This work was carried out to convert glycerol to value-added compounds in liquid phase over TiO₂-based photocatalyst. The investigated parameters were catalyst dosage (1-3 g/L), H₂O₂ concentration (0.3-1.5 mol/L), UV light intensity (1.1-4.7 mW/cm²), reaction time (4-8 h) and electron acceptor types (O₂ and H₂O₂). It was found that TiO₂ in anatase phase can achieved the glycerol conversion of around 71.42% at catalyst dosage of 3 g/L, H₂O₂ concentration of 1.5 mol/L, UV light intensity 4.7 mW/cm² and reaction time 8 h. The addition of monometallic (bismuth, platinum, palladium, and gold) and bimetallic (gold-bismuth, gold-platinum, and gold-palladium) on TiO₂ can …

Synthesis And Optical Properties Of Pyrrolidinyl Peptide Nucleic Acid Carrying Fluorescence Nucleobases, Duangrat Nim-Anussornkul

Chulalongkorn University Theses and Dissertations (Chula ETD)

Pyrrolidinyl peptide nucleic acid bearing D-prolyl-2-aminocyclopentanecarboxylic acid backbone (acpcPNA) is a nucleic acid mimic that shows superior binding affinity, stability and specificity to complementary DNA than the original PNA. This research focuses on the development of hybridization responsive fluorescence acpcPNA probes bearing fluorescent nucleobases that exhibit fluorescence increase upon hybridization to a specific nucleobase in the DNA target. The acpcPNA carrying the fluorescent nucleobases were synthesized via two different approaches, namely 1) pre-synthesized fluorescence PNA monomer as a building block that was subsequently incorporated into the PNA by solid phase synthesis and 2) post-synthetic modification of acpcPNA carrying a reactive …

Application Of Headspace-Gas Chromatography-Mass Spectrometry For Characterization Of Volatile Compounds In Chicken Eggs, Hanan Jehma

Chulalongkorn University Theses and Dissertations (Chula ETD)

Volatile compounds in chicken eggs under the cold chain system and non-cold chain system were characterized by headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) combined with chemometrics. According to a central composite design, the following optimum HS-SPME extraction conditions were obtained: extraction temperature of 65 oC, extraction time of 45 min and the amount of NaCl of 0.4 g. In comparison of their mass spectrum and linear retention index from HS-SPME-GC-MS analysis, major volatile compounds found in egg samples included toluene, hexanal, nonanal and other minor volatile compounds were heptanal, octanal, decanal, benzaldehyde, 1-octen-3-ol and 2-ethyl-1-hexanol, with the types and amounts …

Synthesis Of Cationic Cdse/Zns Quantum Dots And Applications In Dna Detection, Jamornpan Yangcharoenyuenyong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Semiconductor nanoparticles or quantum dots (QDs), especially CdSe/ZnS QDs, are of great interest in bioapplications due to their unique size-dependent optical properties and photo-stability. One of the plausible applications of QDs is DNA detection using QDs as a novel fluorescence tool for sensing of DNA using the electrostatic interaction between negative charge of DNA and positive charge on QDs surface. In this work, CdSe/ZnS QDs were synthesized using a hot-solution decomposition process resulting in hydrophobic CdSe/ZnS QDs. To obtain water-soluble and cationic QDs, the surface of QDs were modified with poly(ethylene)imine (PEI) via micelle formation. Because of hydrophilicity of PEI …

New Edta-Based Drug Delivery Carrier, Nathapong Pangkom

Chulalongkorn University Theses and Dissertations (Chula ETD)

Most of the anticancer drugs are insoluble in water, unspecified to target site and degradable under acidic conditions in the stomach, resulting in decreasing their activities and increasing the side effects. To overcome these problems, drug delivery carriers were used to overcome these problems. Most of the drug delivery carriers were prepared by polymeric micelle systems. However, that of polymeric micelle systems are difficult to synthesize into the random polymers, where different units are aligned on a polymer chain in a random manner, immature drug-incorporation technology and possible chronic liver toxicity due to slow metabolic process. Therefore, the enhancement of …

Preparation Of Rigid Polyurethane Foams Catalyzed By Metal-Asparagine And Metal-Threonine Complexes, Nuttiya Jintana

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research aimed to synthesize metal-amino acid complexes in the form of aqueous solutions to serve as new catalysts for the preparation of rigid polyurethane foams. Aqueous solutions of metal-amino acid complexes were prepared from the reaction of metal acetates with amino acids and water was used as a solvent. Metal acetates employed were copper acetate and zinc acetate. Amino acids employed were asparagine (Asn) and threonine (Thr). Both amino acids are odorless and non-toxic. UV-Vis spectroscopy, FTIR spectroscopy and mass spectrometry were used to characterize metal-amino acid complexes. Metal-amino acid complexes, namely Zn(Asn)₂, Zn(Thr)₂, Cu(Asn)₂ and Cu(Thr)₂ (where Asn …

Colorimetric Detection Of Cyanide Ions Using Complex Formation And Ctab-Coated Silica, Patita Salee

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research presents a new colorimetric method of cyanide detection in solution and water samples based on the extraction of dicyano-bis-(1,10-phenanthroline)-iron(II) complex onto CTAB-coated silica. The complex was formed at pH 10 by using phosphate buffer via the complex formation between tris-(1,10-phenanthroline)-Iron(II) (ferroin) with cyanide ions in CTAB media. When the complex was extracted onto CTAB-coated silica, it resulted in a color change of the material from pale yellow to purple. The changing of color corresponded to cyanide concentration which could be observed by naked-eyes and the color intensity was determined by Image J. The effects of various parameters were …

Fluoride Encapsulation In Calcium Matrix, Piyada Dissara

Chulalongkorn University Theses and Dissertations (Chula ETD)

Fluoride ion (F-) is an important ingredient in a toothpaste. It protects caries by reacting with hydroxyapatite [Ca10(PO)4(OH)2] in tooth enamel to form insoluble fluorapatite [Ca10(PO)4(F)2]. Unfortunately, F- also easily interacts with calcium species in a toothpaste, and then it is deactivated. In this work, we focus on the encapsulation of F- in a shellac bead by using a simple extrusion method. To construct shellac beads, an aqueous solution of F- is injected into an ethanolic solution of shellac. The shellac beads are formed due to insolubility of shellac in water. Then, the beads are transferred into DI water for …

Ferrocene-Bearing Tea Polyphenol Particles As Anticancer Drug Carriers, Punnawich Phaiyarin

Chulalongkorn University Theses and Dissertations (Chula ETD)

Ferrocene is a redox moiety that can be positively charged upon being oxidized. Thus, it is possible to use this moiety to make a polymer platform that is redox responsive regarding their water solubility. Here we prepared polymerized EGCG nanoparticles (pEGCG) and polymerized EGCG gum (pEGCG-gum) from tea polyphenol EGCG. Ferrocene was grafted onto the polymerized tea polyphenol and the obtained polymers were allowed to self-assemble into water-insoluble and indispersible sub-micron particles. The water-insoluble ferrocene-bearing particles became water-dispersible particles with nanometer sizes upon being oxidized by hydrogen peroxide. The oxidized particles, Fc-pEG-gum can inhibit growth of HepG2 liver cancer cells …

Colorimetric Detection Of Cysteine Using Silver-Hydroxyapatite Nanoparticles, Retno Prasetia

Chulalongkorn University Theses and Dissertations (Chula ETD)

Cysteine is a sulphur-containing amino acid that acts as an effective antioxidant in human body. An excessive amount of cysteine leads to cystine formation that causes the stone formation in kidney, bladder, and ureters. A new method was developed for detection of cysteine in urine samples based on the aggregation of silver nanoparticles (AgNPs) on Hydroxyapatite (HAp) in the presence of cysteine. Transmission Electron Microscope (TEM) was used to observe the morphology of prepared HAp and AgNPs on HAp. The presence of cysteine of different concentrations resulted in different cluster sizes of AgNPs on HAp and hence different solid color. …

Synthesis And Supramolecular Polymerization Of Peptide Nucleic Acid-Containing Monomer, Ruttiyakorn Donthongkwa

Chulalongkorn University Theses and Dissertations (Chula ETD)

Nucleobase-induced self-assembly interaction, have gained much attention as potential non-covalent driving force for generating interesting assembled structures. Pyrrolidinyl peptide nucleic acid (PNA), with (2′R,4′R)-prolyl/(1S,2S)-2-aminocyclopentanecarboxylic acid backbone (acpcPNA) has shown the recognition with complementary nucleic acids following Watson-Crick base rules. Another PNA system having different stereochemistry on proline ring with a backbone of (2′R,4′S)-prolyl/(1S,2S)-2-aminocyclopentanecarboxylic acid backbone (epi-acpcPNA) can undergo self-pairing. Here in this work, both acpcPNA- and epi-acpcPNA-functionalized monomers consisting of two PNA segments joined together by a flexible polyethylene glycol linker were prepared on solid support, purified by high performance liquid chromatography (HPLC) and characterized by MALDI-TOF mass spectrometry. The …

Synthesis And Cytotoxicity Evaluation Of Gold Nanoparticles/Pullulan Derivatives For Cancer Treatment, Sakchai Laksee

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study focused on the development of multifunctional gold nanoparticles (AuNPs) using pullulan derivatives as a trifunctional reducing, stabilizing and capping agent for targeted delivery of camptothecin (CPT) or doxorubicin (DOX) in order to enhance their efficacy and reduce side effects. The surface of AuNPs was functionalized to contain 3 beneficial components on pullulan as followed: (i) quat188 as a positive charge to increase cellular uptake and activities, (ii) para-aminobenzoic acid (PABA) as a hydrophobic molecule to enhance biocompatibility, and (iii) folic acid (FA) as a targeting ligand to bind with folate receptor on cancerous cell membranes and enhance intracellular …

Bioactive Compounds From Lichens And Mycobionts In Trypetheliaceae Family, Suekanya Jarupinthusophon

Chulalongkorn University Theses and Dissertations (Chula ETD)

Chemical constituents of two lichens Marcelaria cumingii and Trypethelium subeluteriae, and four cultured mycobionts from M. cumingii, T. platystomum, T. eluteriae and Trypethelium sp. (Trypetheliaceae) were explored. Their secondary metabolites were structurally elucidated by spectroscopic methods as xanthones, anthraquinones, naphthoquinones and phenalenones. Lichexanthone, parietin, xanthorin and emodin were disclosed as constituents of lichens M. cumingii. Whereas, two anthraquinones: parietin and emodin could be isolated from T. subeluteriae together with another anthraquinone, haematommone. The chemical compositions of four cultured mycobionts were found to totally differ from those from lichen. The phenalenone bipolaride C was derived from T. platystomum while two 1,2-naphthoquinones, …

Colorimetric Determination Of Thiocyanate Ion Using Modified Polymer Resins, Sujinda Khaosaard

Chulalongkorn University Theses and Dissertations (Chula ETD)

A new method for thiocyanate determination in milk samples based on the formation of dithiocyanato dipyridine copper(II) [Cu(SCN)2(Py)2] complex on polymer resin surface is proposed. Amberlite XAD-7 resin on was modified with copper-pyridine complex and used as the material for detection. The color of resin changed from blue to green with the increase of thiocyanate concentration. It could be observed by naked-eye and the color intensity used as quantitative data was measured via Image-J software. The effect of various parameters was investigated including Cu2+ concentration, time for resin modification with reagents, sample volume, detection time and pyridine volume. Under the …

Design And Synthesis Of Selenium Nanoparticles To Overcome Multiple Drug Resistance Of Cancer Cells, Urarika Luesakul

Chulalongkorn University Theses and Dissertations (Chula ETD)

The objective of this research is to synthesize selenium nanoparticles (SeNPs) stabilized by chitosan as a drug carrier for delivery doxorubicin to overcome drug-resistant in cancer cells. One important mechanism of multidrug resistance (MDR) includes decreased drug influx and increased drug efflux, leading to insufficient drug concentration to kill cancer cells. Therefore, to overcome MDR by increasing cellular uptake, the surface of SeNP was functionalized to provide 3 structural features: (i) a positive charge to improve their solubility, (ii) gallic acid, a hydrophobic molecule to enhance biocompatibility and (iii) folic acid, a targeting molecule to target cancer cells and enhance …

Synthesis Of Thiofuranosides By Dehydrative Glycosylation In Micellar Media, Trichada Ratthachag

Chulalongkorn University Theses and Dissertations (Chula ETD)

Green and aqueous-based dehydrative glycosylation of thiofuranosides in micellar media was developed. The thiofuranosides are useful as precursors for carbohydrate synthesis, biological active molecules, and bio-surfactants. Dodecylbenzenesulfonic acid (DBSA), a commercially available Brønsted acid-surfactant, was employed to increase solubility of substrates and enhance rate of the glycosylation. Herein, we report the dehydrative glycosylation of furanosides and pyranosides with aliphatic, aromatic, and heterocyclic thiols in aqueous media to afford the thiofuranosides. Microwave irradiation led to improved yields and shorter reaction times. Other reaction parameters such as temperature and the amount of acid used were also optimized. Aliphatic and aromatic thiofuranosides were …

Characterization Of Non-Volatile Compounds In Tom Yum Soup Using High Performance Liquid Chromatography-Tandem Mass Spectrometry, Wanabud Wongbubpha

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this work, high performance liquid chromatography hyphenated with tandem mass spectrometry (HPLC-MS/MS) was developed and validated for simultaneous determination of 31 targeted non-volatile compounds, such as 2 organic acids, 20 amino acids and 9 phenolic acids, in Tom Yum ingredient, Tom Yum soup made from the fresh ingredients and commercial Tom Yum pastes, where the main Tom Yum ingredients include galangal, lemongrass, kaffir lime leaves, Bird's eye chili, lime juice and fish sauce. The following HPLC-MS/MS conditions were used: a PoroShell C18 column (4.6 x 100 mm, 2.7 µm) using a gradient elution of A:B mobile phase at a …

Synthesis And Development Of Dipicolylamine Derivatives As New Fluorescent Chemosensors, Waroton Paisuwan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Di-2-picolylamine (DPA) is a powerful chelator for many transition metal ions. In this thesis, new DPA fluorescent chemosensors consisting of a fluorophore such as either naphthalimide or quinoline are developed. The first part deals with the synthesis of 1,8-naphthalimide derivatives linked 2-, 3-, 4-((bis(pyridin-2-ylmethyl)amino)methyl)aniline, and 4-amino-2-((bis(pyridin-2-ylmethyl)amino)methyl)phenol. The metal ion sensing experiments showed N3D was selective toward Ag+ with fluorescent enhancement in aqueous emitting green fluorescence under blacklight. The complexation of [N3D+Ag+] is a 1:1 stoichiometric binding with a limit of detection (LOD) 0.67 µM. Second part is the synthesis of oxazolidinonyl DPA derivatives by using self-developed halo-induced cyclization followed by …