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Cyanide Fluorescent Sensors From Indolium-Fluorophore Conjugates, Siraporn Soonthonhut Jan 2022

Cyanide Fluorescent Sensors From Indolium-Fluorophore Conjugates, Siraporn Soonthonhut

Chulalongkorn University Theses and Dissertations (Chula ETD)

Indolium conjugated with three fluorophores including julolidine, triphenylamine, and pyrene (INJ, INT, INP) were successfully synthesized via condensation reaction with an excellent yield over 80%. All of derivatives were fully characterized and investigated the photophysical properties revealing that synthesized indolium-fluorophore conjugates has a negligible quantum yield. All synthesized compounds expressed the great selectivity toward cyanide ion indicating by colorimetric and fluorescence signal change due to internal charge transfer process (ICT) was interrupted. The sensitivity on cyanide detection was carried on both colorimetric and fluorescence mode resulting the excellent sensitivity on INT and INJ which can be operated for analysis of …


Analysis Of Fatty Acid Methyl Esters By Two-Dimensional Gas Chromatography Using Cryogen-Free Modulator, Adrian Jose Sacan Jan 2022

Analysis Of Fatty Acid Methyl Esters By Two-Dimensional Gas Chromatography Using Cryogen-Free Modulator, Adrian Jose Sacan

Chulalongkorn University Theses and Dissertations (Chula ETD)

A simple and environmentally friendly method in two-dimensional gas chromatography coupled with mass spectrometry (GC-MS) and flame ionization detector has been developed for the analysis of fatty acids in commercial milk products. This applies splitter-based non-cryogenic artificial trapping (SNAT) modulator with unique feature imitating the cryogenic modulation process. The method involves chemical derivatization into fatty acid methyl esters (FAME) with methanolic potassium hydroxide, liquid-liquid phase extraction using hexane, and determination of the FAME composition. The GC×GC approach revealed improved separation of FAME using SNAT modulator with better separated peaks, a ten-fold higher total peak capacity and improved compound identification, compared …


Application Of Core Annular Flow For Oil Transportation In Different Pipe Configurations Using Computational Fluid Dynamics, Cindy Dianita Jan 2022

Application Of Core Annular Flow For Oil Transportation In Different Pipe Configurations Using Computational Fluid Dynamics, Cindy Dianita

Chulalongkorn University Theses and Dissertations (Chula ETD)

The application of Core Annular Flow (CAF) has become an interesting solution in transporting heavy oil through pipeline because of its energy reduction and cost efficiency. Current study conducted a 3D computational fluid dynamic (CFD) to simulate CAF of oil-water in horizontal T- and Y-pipe junctions with two types of oil characteristic i.e., oil as Newtonian fluid and oil as non-Newtonian Carreau Fluid. The 2k factorial statistical experimental design was applied to investigate the effect of geometry on the flow performance. Eight cases were run with different diameter combinations and junction angle. The most attractive design was measured by the …


Preparation Of Cellulose Micro- And Nano Fibers From Bagasse Through Deep Eutectic Solvent System, Worapoj Phuckpetch Jan 2022

Preparation Of Cellulose Micro- And Nano Fibers From Bagasse Through Deep Eutectic Solvent System, Worapoj Phuckpetch

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study aimed to prepare the cellulose micro- and nanofibers (CMNFs) using green chemistry viewpoint. The CMNFs were fabricated from sugarcane bagasse (SCB) pulp through treatment with zinc chloride (ZnCl2) - lactic acid (LA) in deep eutectic solvent (ZnCl2-LA DES) followed by short time ultrasonication of the DES-treated fibers in water. Under the optimum condition, the SCB pulp at high solid loading of 6.25% was treated with ZnCl2-LA DES. Lactate functionalized CMNFs with 230-270 nm length and 15-16 nm width were resulted in more than 90% yield and up to 62.2% crystallinity. The results showed that ZnCl2-LA DES was a …


การผลิตไบโอดีเซลจากน้ำมันกากกาแฟบดโดยเอทานอลภาวะเหนือวิกฤต, ณัฐกิตติ์ เจริญดี Jan 2022

การผลิตไบโอดีเซลจากน้ำมันกากกาแฟบดโดยเอทานอลภาวะเหนือวิกฤต, ณัฐกิตติ์ เจริญดี

Chulalongkorn University Theses and Dissertations (Chula ETD)

ไบโอดีเซล (Biodiesel) เป็นหนึ่งในพลังงานทางเลือกชีวภาพที่สามารถผลิตได้จากแหล่งพลังงานหมุนเวียนเช่น น้ำมันพืช และไขมันสัตว์ ในกระบวนการผลิตไบโอดีเซลพบปัญหาด้านราคาต้นทุนวัตถุดิบที่มีราคาสูงซึ่งคิดเป็นร้อยละ 70 ของต้นทุนทั้งหมด กากกาแฟเป็นของเสียหลักจากกระบวนการผลิตกาแฟซึ่งมีองค์ประกอบของไขมันอยู่ร้อยละ 18 ถึง 20 ของน้ำหนัก ทำให้สามารถนำมาใช้เป็นวัตถุดิบสำหรับผลิตไบโอดีเซลเพื่อลดต้นทุนการผลิตได้อีกทางหนึ่ง งานวิจัยนี้ศึกษากระบวนการผลิตไบโอดีเซลจากน้ำมันกากกาแฟบดด้วยเอทานอลภาวะเหนือวิกฤตในเครื่องปฏิกรณ์แบบแบตช์ และแบบต่อเนื่อง และหาภาวะที่ให้ร้อยละกรดไขมันเอทิลเอสเทอร์ (Fatty acid ethyl ester, FAEE) สูงสุด จากผลการทดลองพบว่าปริมาณน้ำมันกากกาแฟบดสูงสุดที่สามารถสกัดด้วยวิธีซอกห์เลตโดยใช้ตัวทำละลายเอทานอลได้ปริมาณน้ำมันกากกาแฟบดร้อยละ 27.67 ของน้ำหนักกากกาแฟบด ในกระบวนการผลิตไบโอดีเซลด้วยเครื่องปฏิกรณ์แบบแบตช์ พบว่าปริมาณกรดไขมันเอทิลเอสเทอร์จะเพิ่มขึ้นเมื่ออุณหภูมิและเวลาในการทำปฏิกิริยาเพิ่มขึ้น โดยที่อุณหภูมิ 275 องศาเซลเซียส และเวลาในการทำปฏิกิริยา 40 นาที จะให้ปริมาณกรดไขมันเอทิลเอสเทอร์สูงสุดร้อยละ 88.37 สำหรับกระบวนการผลิตไบโอดีเซลด้วยเครื่องปฏิกรณ์แบบต่อเนื่อง พบว่าเมื่อเพิ่มอัตราการไหลจะทำให้เวลาของสารตั้งต้นในเครื่องปฏิกรณ์ลดลง ส่งผลทำให้ปริมาณกรดไขมันเอทิลเอสเทอร์มีปริมาณลดลง ที่อุณหภูมิ 325 องศาเซลเซียส อัตราการไหล 2 กรัมต่อนาที และเวลาของสารตั้งต้นในเครื่องปฏิกรณ์ 25.16 นาที จะให้ปริมาณกรดไขมันเอทิลเอสเทอร์ที่สูงสุดร้อยละ 83.35


ผลของชาร์ที่กระตุ้นด้วยโพแทสเซียมไฮดรอกไซด์และไอน้ำต่อการผลิตน้ำมันดิบชีวภาพจากชานอ้อยโดยไฮโดรเทอร์มัลลิควิแฟกชัน, สราวรรณ ทรัพย์พันธ์ Jan 2022

ผลของชาร์ที่กระตุ้นด้วยโพแทสเซียมไฮดรอกไซด์และไอน้ำต่อการผลิตน้ำมันดิบชีวภาพจากชานอ้อยโดยไฮโดรเทอร์มัลลิควิแฟกชัน, สราวรรณ ทรัพย์พันธ์

Chulalongkorn University Theses and Dissertations (Chula ETD)

พลังงานจากชีวมวลเป็นพลังงานทางเลือกหนึ่งที่ได้รับความสนใจเพื่อแก้ปัญหาและข้อจำกัดจากเชื้อเพลิงฟอสซิล ไฮโดรเทอร์มัลลิควิแฟกชัน (Hydrothermal liquefaction, HTL) เป็นกระบวนการแปรรูปชีวมวลเป็นเชื้อเพลิงเหลว เนื่องด้วยกระบวนการนี้ยังสามารถปรับปรุงคุณภาพของน้ำมันและปริมาณน้ำมันได้ด้วยการใส่ตัวเร่งปฏิกิริยาลงไปในกระบวนการ ซึ่งตัวเร่งปฏิกิริยาที่น่าสนใจคือ ชาร์ เนื่องจากมีสมบัติเป็นตัวเร่งปฏิกิริยา สามารถผลิตได้ง่ายจากชีวมวล และ ราคาถูก อีกทั้งยังไม่มีงานวิจัยที่ศึกษาผลของชาร์ ที่ส่งเสริมการเร่งปฏิกิริยาในกระบวนการไฮโดรเทอร์มัลลิควิแฟกชัน งานวิจัยนี้จึงสนใจในการนำชานอ้อยและชาร์ มาเป็นสารป้อนร่วมในกระบวนการไฮโดรเทอร์มัลลิควิแฟกชัน โดยใช้ชาร์มากระตุ้นด้วยไอน้ำและใช้โพแทสเซียมไฮดรอกไซด์ (KOH) เป็นตัวช่วยกระตุ้น เพื่อนำมาเพิ่มประสิทธิภาพในการผลิตน้ำมันดิบชีวภาพจากชานอ้อยโดยกระบวนการ HTL โดยขั้นตอนในงานวิจัยนี้แบ่งออกเป็น 2 ส่วน คือ ขั้นแรก ขั้นของการกระตุ้น เป็นการกระตุ้นถ่านชาร์ด้วยโพแทสเซียมไฮดรอกไซด์และไอน้ำ ซึ่งจะศึกษาผลของอัตราส่วนระหว่างโพแทสเซียมและถ่านชาร์ที่ร้อยละ 2.5 และ 5 โดยน้ำหนัก และผลของอุณหภูมิในการกระตุ้นที่ 700, 800 และ 900 องศาเซลเซียส พบว่า เมื่อใช้อุณหภูมิในการกระตุ้นสูงขึ้น ร้อยละผลได้ของถ่านชาร์หลังการกระตุ้นจะลดลง ส่วนในขั้นที่ 2 เป็นการทำไฮโดรเทอร์มัลลิควิแฟกชัน โดยดำเนินการในเครื่องปฏิกรณ์ความดันสูงแบบแบตช์ที่อุณหภูมิ 300 และ 325 องศาเซลเซียส ที่ความดันเริ่มต้น 2 เมกะพาสคัล โดยใช้เวลาในการทำปฏิกิริยา 60 นาที พบว่า ร้อยละผลได้ของน้ำมันดิบชีวภาพจะเพิ่มขึ้น เมื่อใช้ชานอ้อยร่วมกับชาร์ที่ถูกกระตุ้นด้วยไอน้ำและโพแทสเซียมไฮดรอกไซด์ เนื่องจากชาร์มีผลในการเร่งปฏิกิริยาการแตกตัวของชีวมวล อีกทั้งโพแทสเซียมไฮดรอกไซด์ยังช่วยเสริมการทำงานร่วมกับชานอ้อยได้ดียิ่งขึ้น โดยให้ร้อยละน้ำมันดิบชีวภาพสูงถึง 29.91% ในส่วนของอุณหภูมิในการทำปฏิกิริยาที่ 300 และ 325 องศาเซลเซียส พบว่าเมื่อใช้อุณหภูมิในการทำปฏิกิริยาที่สูงขึ้นร้อยละผลได้ของน้ำมันดิบจะเพิ่มขึ้น นอกจากนี้ เมื่อใช้ชาร์ที่ถูกกระตุ้นด้วยไอน้ำและโพแทสเซียมไฮดรอกไซด์ร่วมในกระบวนการไฮโดรเทอร์มัลลิควิแฟกชัน จะส่งผลช่วยปรับปรุงคุณภาพของน้ำมันชีวภาพ โดยพิจารณาจากค่าความร้อนสูง


Synthesis Of Benzofuropyridine Derivatives As Cdk-5 Inhibitors And Anticancer Agents, Reymark Ereje Jan 2022

Synthesis Of Benzofuropyridine Derivatives As Cdk-5 Inhibitors And Anticancer Agents, Reymark Ereje

Chulalongkorn University Theses and Dissertations (Chula ETD)

Cancer is a disease characterized by abnormal cell proliferation. Current cutting-edge therapies like biologics are limited due to their complicated approaches and unknown efficacy, thus small molecule-based drugs remain the viable option. Benzofuropyridines (BFP) are a class of tricyclic small molecules derived from the α-carboline. Even with reported anticancer potential of BFP, an extensive derivatization of its core structure remains scarce and unexplored. In this work, twenty-five novel BFP analogues were synthesized. Biological activity assessment was performed against cancer cell lines. Molecular docking study was conducted to suggest a possible inhibition mechanism. The results of the assay highlighted that the …


Gas Chromatographic Simulation For Experiential Learning Evaluation, Nattawat Thanasarnchokephiboon Jan 2022

Gas Chromatographic Simulation For Experiential Learning Evaluation, Nattawat Thanasarnchokephiboon

Chulalongkorn University Theses and Dissertations (Chula ETD)

Obtaining critical thinking skills for optimizing and selecting experimental conditions in gas chromatography (GC) is a challenge for high school students. The students cannot traditionally percieve such skills in lecture classes since the learning process is time-consuming and expensive in terms of energy and resources. To address this issue, this study proposes an alternative simulation-based approach to improve the optimization skills of a wide range of students, including 10 Matthayom 4 (Grade 10) students, 8 third-year bachelor students, 8 master students, and 9 PhD volunteering students. The approach used a computer spreadsheet platform with the capability to perform fast simulation …


Design, Synthesis, And Biological Test Of Lapatinib Analogs As Inhibitors For Sars-Cov-2 Main Proteases, Ayomide Adediji Jan 2022

Design, Synthesis, And Biological Test Of Lapatinib Analogs As Inhibitors For Sars-Cov-2 Main Proteases, Ayomide Adediji

Chulalongkorn University Theses and Dissertations (Chula ETD)

The coronavirus disease, COVID-19, continues to ravage and pose threats to health and economies, especially with the unceasing appearance of new variants, emphasizing the need for continuous efforts in its drug development. Recently, lapatinib, a breast cancer drug, has been reported, through repurposing, to possess SARS-CoV-2 main protease inhibitory potential as a core structure for further development in COVID-19 drug development. Therefore, in this study, various lapatinib fragments have been designed and evaluated for their binding affinity toward the main protease. The optimal fragment was selected as the core structure for the synthesis of lapatinib analogs using a building block …


Michael Addition Using Dialkyldithiocarbamate And Xanthate Derivatives As Organocatalysts, Hafiz Muhammad Qamar Farid Jan 2022

Michael Addition Using Dialkyldithiocarbamate And Xanthate Derivatives As Organocatalysts, Hafiz Muhammad Qamar Farid

Chulalongkorn University Theses and Dissertations (Chula ETD)

The Michael addition is an effective tool for carbon-carbon bond formation. Recently, our research group has developed the Michael addition of beta-nitrostyrenes in water using a salt of N,N-dialkyldithiocarbamate (DTC) as novel organocatalysts with a broad scope of substrates and high yields of Michael adducts. However, the reaction rates were slow; we hypothesized that the reaction rates were hindered by competitive hydrogen bonding between the DTC organocatalyst and water. Furthermore, DTC salts are prone to oxidize in the presence of oxygen. Hence, we herein investigated the Michael additions using the DTC salts as organocatalysts in organic solvents as a reaction …


Bioactive Compounds From Leaves And Heartwoods Of Santol Sandoricum Koetjape Merr., Tai Xuan Hoa Hang Jan 2022

Bioactive Compounds From Leaves And Heartwoods Of Santol Sandoricum Koetjape Merr., Tai Xuan Hoa Hang

Chulalongkorn University Theses and Dissertations (Chula ETD)

Phytochemical and biological investigations were conducted on the leaves and heartwoods of Sandoricum koetjape. From the potent methanol extracts, twenty known compounds (3-15, 17-20, 28-30), three new compounds (1-2, 21), and seven novel compounds (16, 22-27) were isolated. Their structures were elucidated by spectroscopic data analysis (1D, 2D NMR and HRESIMS). Isolated compounds were evaluated for enzyme inhibitory activity against α-glucosidase and cytotoxicity activity. Quercetin (10) from the leaves and (+)-lyoniresinol 3-α-O-b-D-glucopyranoside (30) from the heartwoods showed significant inhibitory activity against yeast α-glucosidase with IC50 value of 2.2±0.1 and 2.8±0.8 mM, respectively which were around 40 times lower than that …


ผลของชั้นระหว่างหน้าต่อการปรับปรุงเสถียรภาพของเซลล์สุริยะชนิดเพอรอฟสไกต์, พีรดนย์ พงษ์ลำเจียกงาม Jan 2022

ผลของชั้นระหว่างหน้าต่อการปรับปรุงเสถียรภาพของเซลล์สุริยะชนิดเพอรอฟสไกต์, พีรดนย์ พงษ์ลำเจียกงาม

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้นำเสนอกลยุทธ์ปรับปรุงเสถียรภาพของเซลล์สุริยะชนิดเพอรอฟสไกต์ด้วย สารปรับปรุงชั้นระหว่างหน้า (self-Assembly monolayer 2 ชนิด) ได้แก่ Triethoxy (4-methoxyphenyl) silane (SAM1) และ Triethoxy (3,4-dimethoxyphenyl) silane (SAM2) เพื่อประยุกต์เป็นชั้นแทรกระหว่างชั้นส่งผ่านอิเล็กตรอนไทเทเนียมไดออกไซด์ (TiO2) และชั้นสารดูดกลืนแสงเพอรอฟสไกต์ [FA0.83Cs0.17Pb(I0.83 Br0.17 )3] โดยสังเคราะห์จากอนุพันธ์ของไซเลนผ่านปฏิกิริยาการเติมแบบกรีญาร์ ผลการคำนวณเกาส์เชียนพบว่าโครงสร้างของ SAM1 มีค่าโมเมนต์ขั้วคู่สูงกว่า SAM2 ผลการพิสูจน์ลักษณะสมบัติพบว่าฟิล์ม TiO2 ที่ปรับปรุงด้วย SAM ทั้งสองชนิดมีสภาพไม่ชอบน้ำเพิ่มขึ้น ฟิล์มประกอบ TiO2/SAM1 มีช่องว่างระหว่างแถบพลังงานลดลงเทียบกับฟิล์มประกอบ TiO2/SAM2 และฟิล์ม TiO2 ที่ไม่ผ่านการปรับปรุง ผลทดสอบสมบัติทางไฟฟ้าเบื้องต้นพบว่าเซลล์ทดสอบที่ปรับปรุงด้วย SAM1 ให้ค่าความหนาแน่นกระแสไฟฟ้า (Jsc) เพิ่มสูงขึ้นร้อยละ 75 เทียบกับเซลล์ทดสอบที่ไม่ผ่านการปรับปรุง นอกจากนั้น ผลทดสอบเสถียรภาพของฟิล์มประกอบ TiO2/FA0.83Cs0.17Pb(I0.83 Br0.17)3 และฟิล์มประกอบที่ปรับปรุงชั้น TiO2 ด้วย SAM1 และ SAM2 โดยใช้เทคนิคยูวี-วิสิเบิลสเปกโตรสโคปี ทดสอบในสภาวะมืดเป็นเวลา 14 วัน พบว่าฟิล์มประกอบ TiO2-SAM1/FA0.83Cs0.17Pb(I0.83 Br0.17)3 ตรวจไม่พบการสลายตัวของชั้นเพอรอฟไกต์ ขณะที่ฟิล์มประกอบ TiO2-SAM2/FA0.83Cs0.17Pb(I0.83 Br0.17)3 และฟิล์มประกอบที่ไม่ผ่านการปรับปรุง ตรวจพบการสลายตัวของชั้นเพอรอฟสไกต์ภายใน 4 และ 12 วัน ตามลำดับ


Synthesis Of Furocoumarin Derivatives As Anti-Cancer Agents, Chiphada Aekrungrueangkit Jan 2022

Synthesis Of Furocoumarin Derivatives As Anti-Cancer Agents, Chiphada Aekrungrueangkit

Chulalongkorn University Theses and Dissertations (Chula ETD)

Furocoumarin derivatives are one of interesting scaffolds which show potential as an anti-cancer agent. The previous work has found the anticancer activity especially of the methoxsalen (8-MOP) derivatives with an amide group at the C-5 position. However, the scope of the substituents in the previous study on this scaffold remains lacking. Additionally, despite the promising anticancer properties of these furocoumarin derivatives, the information about mechanism of action or target enzymes is still inconclusive. Herein, a series of furocoumarin derivatives with C-5 substitution were successfully synthesized and evaluated for their in vitro cytotoxicity against eight cancer cell lines: breast cancers (MDA-MB-231 …


Electrochemical Cyclization Of Chalcones For Synthesis Of Flavones, Taweesak Gulchatchai Jan 2022

Electrochemical Cyclization Of Chalcones For Synthesis Of Flavones, Taweesak Gulchatchai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Flavone is considered as one of the important compounds in pharmaceutical and medicinal fields due to the existence of various biological activities, leading to various flavone synthetic methods. Even though most of the reported methods are efficient, they involve the use of harsh conditions, strong oxidizing agents, expensive metal catalysts, hazardous solvents, or multistep synthesis of starting materials. To overcome these limitations, in this work, we developed a novel electrochemical cyclization reaction for the synthesis of flavones from easy-access 2’-hydroxychalcones. In this electrochemical cyclization, platinum plates were used as electrodes in ethanol/water solvent under open air and room temperature in …


Development Of Electrochemical Sensor For L-Hydroxyproline And Interleukin-6 Detections, Whitchuta Jesadabundit Jan 2022

Development Of Electrochemical Sensor For L-Hydroxyproline And Interleukin-6 Detections, Whitchuta Jesadabundit

Chulalongkorn University Theses and Dissertations (Chula ETD)

This dissertation is research on the development of biosensors using different types of bioreceptors and nanomaterials for the diagnostic application of various diseases. The research is separated into two parts. The first part is about the development of an enzyme-free impedimetric sensor based on molecularly imprinted polymer (MIP) for the selective determination of L-hydroxyproline (L-hyp), a biomarker of bone diseases. It was found that the use of a mixture containing 3-aminophenylboronic acid (3-APBA) functions as a monomer and o -phenylene diamine (OPD) as a co-monomer can generate the specific MIP through electropolymerization. The detection is based on the increase of …


Development Of Paper-Based Electrochemical Immunosensor For Sars-Cov-2 Detection, Jutamas Jaewjaroenwatana Jan 2022

Development Of Paper-Based Electrochemical Immunosensor For Sars-Cov-2 Detection, Jutamas Jaewjaroenwatana

Chulalongkorn University Theses and Dissertations (Chula ETD)

This dissertation aimed to develop a simple and low-cost electrochemical sensing platform for detecting SAR-CoV-2 antigen. The proposed sensor combined the innovative disposable paper-based immunosensor and cost-effective plant-based anti-SARS-CoV-2 monoclonal antibody, extracted from Nicotiana benthamiana. The cellulose nanocrystal was modified on screen-printed graphene electrode to provide the COOH functional groups on electrode surface, leading to the high ability for antibody immobilization. The quantification of the presence receptor binding domain (RBD) spike protein of SARS-CoV-2 was performed using differential pulse voltammetry by monitoring the changing current of [Fe(CN)6]3-/4- redox solution. The current change of [Fe(CN)6]3-/4- before and after the presence of …


Delayed Lateral Flow Immunoassay For Determination Of Covid-19 Antigen, Pawanrat Srithong Jan 2022

Delayed Lateral Flow Immunoassay For Determination Of Covid-19 Antigen, Pawanrat Srithong

Chulalongkorn University Theses and Dissertations (Chula ETD)

The lateral flow immunoassay (LFIA) strip is one of the most attractive biosensing platforms for a point-of-care testing (POCT). However, the generally lack of sensitivity and inability to perform quantitative analysis has consequently limited its outreaches for more challenging applications, where detecting low analytic concentrations is required. To overcome such drawbacks, we propose a facile and straightforward alternative method utilizing a delayed hydrophobic barrier fabricated with trimethylsilyl cellulose (TMSC) to improve its sensitivity. The SARS-CoV-2 spike receptor-binding domain (SARS-CoV-2 SP RBD) antigen was chosen as a model analyte to demonstrate the superior detectability of this scheme. The novel device consists …


Glycosylation Of N-Pentenyl Glycoside Activated By Bromodiethylsulfonium Salt, Supanat Buntasana Jan 2022

Glycosylation Of N-Pentenyl Glycoside Activated By Bromodiethylsulfonium Salt, Supanat Buntasana

Chulalongkorn University Theses and Dissertations (Chula ETD)

n-Pentenyl glycosides (NPGs) are a significant class of glycosyl donors with dual functionality, serving as both protecting groups for the anomeric hydroxyl and leaving groups upon activation with halonium activators such as N-bromosuccinimide (NBS) or N-iodosuccinimide (NIS). However, the activation of less reactive glycosyl donors with these reagents has proven to be sluggish and inefficient. Recently, bromodiethylsulfonium bromopentachloroantimonate (BDSB) has emerged as a highly efficient brominating reagent that can be readily prepared and purified through crystallization. In this study, we explored the potential of BDSB as a halonium activator for NPGs in chemical glycosylation reactions. By using BDSB as the …


Gc/Ms And Lc/Ms Approaches To Chemical Communication In Plants And Marine Cyanobacteria, Carolyn Keim Jan 2022

Gc/Ms And Lc/Ms Approaches To Chemical Communication In Plants And Marine Cyanobacteria, Carolyn Keim

University of the Pacific Theses and Dissertations

Natural products are small organic compounds synthesized by living organisms including plants, animals, and microbes. These fall into one of two categories, primary metabolites are required for survival, but secondary metabolites usually play a more accessory role. Extracts from organisms have proven to be useful to humans throughout history. Prior to evidence-based western medicine practices, natural products were the only source of medicine and remain as a treatment source for underdeveloped nations. Today, natural products have either been approved by or have served as the template for many FDA approved drugs. Based on a survey of all FDA approved drugs …


Synthesis And Modeling Of Manganese Ferrite Nanoparticles For Magnetic Hyperthermia Applications, Margaret E. Thornton Jan 2022

Synthesis And Modeling Of Manganese Ferrite Nanoparticles For Magnetic Hyperthermia Applications, Margaret E. Thornton

Theses and Dissertations

Biologically targeted magnetic hyperthermia (MH) is a promising cancer therapeutic that is both non-invasive and has the potential to serve as a single-modality cancer treatment. MH operates through the elevation of temperatures between 40-43 °C to induce apoptosis in malignant tumor cells, while the small size of the magnetic nanoparticles preserves the healthy surrounding tissue. At present, MH is limited by low heating efficiency and heterogenous outcomes, and treatment requires direct-injection of the nanoparticles, excluding deep-tissue and metastatic tumors from the therapy. The most popular candidates for MH are the spinel ferrites iron oxide and manganese iron oxide (MFO). These …


Analysis Of Microdroplets And Microorganisms By Single Entity Electrochemistry, Junaid U. Ahmed Jan 2022

Analysis Of Microdroplets And Microorganisms By Single Entity Electrochemistry, Junaid U. Ahmed

Theses and Dissertations

Single Entity Electrochemistry (SEE) is an emerging electrochemical technique that has been used to characterize discrete entities by measuring the change in current or potential during individual stochastic events (collision or adsorption) of an entity with an ultramicroelectrode (UME) of similar dimensions. The shape and magnitude of the SEE signal depend on the underlying mechanism of interaction with the UME surface. There is a critical need for quantitative models that correlate the SEE signal with properties of the entity-UME system, including effects of acquisition instrumentation, to prevent misinterpretation of data.

This research focused on integrated experiments and simulations to quantify …


Antiviral Effects Of Metalloshielding: Differential Antiviral Activity Of Polynuclear Platinum And Cobalt Compounds, Mary Zoepfl Jan 2022

Antiviral Effects Of Metalloshielding: Differential Antiviral Activity Of Polynuclear Platinum And Cobalt Compounds, Mary Zoepfl

Theses and Dissertations

The majority of antiviral drug development has focused on virus-specific discovery targeting discrete steps in the individual life cycles. Although great strides have been made for a number of clinically relevant diseases such as human immunodeficiency virus, influenza virus, and hepatitis B, broad spectrum antivirals do not exist. Broad spectrum antivirals would offer (1) treatment for viruses without specifically-targeted antivirals, (2) treatment for viruses which have developed resistance to their available treatments, and (3) a rapidly deployable treatment option in viral epidemics. Many viruses including human cytomegalovirus (HCMV), HIV, and SARS-CoV-2. rely on heparan sulfate (HS), a highly sulfated glycosaminoglycan …


Behavioral Screening And Chiral Bioanalysis Of Emerging Stimulant-Type Drugs In Rats, Tyson R. Baird Jan 2022

Behavioral Screening And Chiral Bioanalysis Of Emerging Stimulant-Type Drugs In Rats, Tyson R. Baird

Theses and Dissertations

The epidemic of drug use in the United States and elsewhere in the world has resulted in tragic loss of life and substantial economic costs. Novel psychoactive substances (NPS) are one of the contributors to this problem, and the lack of information about many of these drugs compounds their risk. This dissertation proposes a strategy to use intracranial self-stimulation (ICSS) as a behavioral screening tool to assess emerging drugs of abuse for their abuse potential in order to generate a proactive threat assessment. A series of stimulant-type drugs including methcathinone, α-pyrrolidinohexanophenone (α-PHP), cocaine, and the phenyltropane analogs of cocaine WIN35428 …


Asymmetric Cuh-Catalyzed Reductive Coupling Of Alleneamides With Carbonyl Electrophiles And The Mechanistic Investigation Into The Suzuki-Miyaura Cross-Couplings Of Electron-Deficient Systems, Samantha L. Gargaro Jan 2022

Asymmetric Cuh-Catalyzed Reductive Coupling Of Alleneamides With Carbonyl Electrophiles And The Mechanistic Investigation Into The Suzuki-Miyaura Cross-Couplings Of Electron-Deficient Systems, Samantha L. Gargaro

Theses and Dissertations

Most natural products and other biologically active small molecules contain multiple stereogenic heteroatoms throughout their carbon scaffold. As a result, methods to install these multi-heteroatom functionalities efficiently are highly desirable. Reductive coupling reactions have been studied extensively, and reductive allylation has been a key method for generating chiral secondary and tertiary allylic alcohols. This work focuses on utilizing naturally abundant and inexpensive Cu for the asymmetric reductive coupling of alleneamides with carbonyl electrophiles to access highly functionalized multi-heteroatom scaffolds that are difficult to produce via traditional methods. Described herein are methods for these asymmetric reductive coupling reactions. Chapter 1 describes …


Formulation, Structure, And Applications Of Therapeutic, Amino Acid, And Water-Based Deep Eutectic Solvents, Md Sajjadur Rahman Jan 2022

Formulation, Structure, And Applications Of Therapeutic, Amino Acid, And Water-Based Deep Eutectic Solvents, Md Sajjadur Rahman

Electronic Theses and Dissertations

In the design of greener chemicals, deep eutectic solvents (DESs) are considered as one of the most versatile alternative solvents with widespread applications. DESs have the advantages of being nonflammable with negligible vapor pressure compared to traditional solvents. They share many characteristics of ionic liquids, but DESs are cheaper to formulate, typically nontoxic, recyclable, biodegradable, and are suitable for use with biological systems. In my Ph.D. research, three types of emerging and unconventional types of DESs, namely therapeutic DES (THEDES), amino acid-based DES (AADES), and water-based DES (WDES), have been investigated. To formulate these DES easily available and cheaper chemicals, …


Characterizing The Effects Of Solvent And Analyte Properties On Ionization Efficiency By Novel Field-Free And Field-Enabled Ionization Techniques, Kinkini Udara Jayasundara Jan 2022

Characterizing The Effects Of Solvent And Analyte Properties On Ionization Efficiency By Novel Field-Free And Field-Enabled Ionization Techniques, Kinkini Udara Jayasundara

Graduate Theses, Dissertations, and Problem Reports (ETD)

In recent years the mass spectrometry (MS) area of field and/or direct analysis has grown dramatically. As a result, field-portable and miniaturized mass spectrometers, introduced only a few years ago, are proliferating. A highly desired feature for field-portable MS, or in-field analysis, is the ability to use ionization techniques requiring very little sample preparation as well as an ability to generate the ions under ambient conditions. Recently, a new ambient ionization technique termed vibrating sharp-edge spray ionization (VSSI) has been introduced which overcomes the field-portable limitations of other spray-based methods including the requirements for auxiliary components (e.g., nebulizing gas and …


Chromatographic Studies Of Some Hormone And Metabolic Modulators Used For Doping In Sports, Ruth Marie Speidel Jan 2022

Chromatographic Studies Of Some Hormone And Metabolic Modulators Used For Doping In Sports, Ruth Marie Speidel

Online Theses and Dissertations

The World Anti-Doping Agency (WADA) is an international agency that monitors the use of Performance Enhancing Drugs (PEDs) in sports; their mission is “to lead a collaborative worldwide movement for doping-free sport” (Who We Are, 2022). For this mission, the WADA needs quick, sensitive, reproducible, and accurate methods for analyzing athletes’ biological fluids for possible PEDs. This research focuses on developing and validating simple, sensitive, rapid, and reliable gas chromatography- mass spectrometry (GC-MS) methods for the analysis of two hormone and metabolic modulators, toremifene and trimetazidine. Previously, there has been limited GC-MS methods used to analyze toremifene and trimetazidine. Quantification …


Biomolecular Corona Stability In Association With Plasma Cholesterol Level, Duong N. Trinh, Meda Radlinskaite, Jack Cheeseman, Gunther Kuhnle, Helen M.I. Osborn, Paula Meleady, Daniel I.R. Spencer, Marco P. Monopoli Jan 2022

Biomolecular Corona Stability In Association With Plasma Cholesterol Level, Duong N. Trinh, Meda Radlinskaite, Jack Cheeseman, Gunther Kuhnle, Helen M.I. Osborn, Paula Meleady, Daniel I.R. Spencer, Marco P. Monopoli

Articles

Biomolecular corona is spontaneously formed on the surface of nanoparticles (NPs) when they are in contact with biological fluids. It plays an important role in the colloidal stability of NPs, which is of importance for most of their medical applications and toxicity assessment. While typical studies use either blood plasma or serum from a pooled biobank, it is unclear whether differences in the media, such as cholesterol level or protein concentration, might affect the NP colloidal stability and corona composition. In this study, the silica corona was prepared at particularly low plasma concentrations (3%, v/v–1.98 mg/mL) to identify the critical …


Synthesis And Investigation Of Antiproliferative Activity Of Ru-Nhc Complexes Against C6 And Hela Cancer Cells, Ramazan Paşahan, Mi̇tat Akkoç, Şeyma Yaşar, Tuğba Kul Köprülü, Şaban Teki̇n, Sedat Yaşar, İsmai̇l Özdemi̇r Jan 2022

Synthesis And Investigation Of Antiproliferative Activity Of Ru-Nhc Complexes Against C6 And Hela Cancer Cells, Ramazan Paşahan, Mi̇tat Akkoç, Şeyma Yaşar, Tuğba Kul Köprülü, Şaban Teki̇n, Sedat Yaşar, İsmai̇l Özdemi̇r

Turkish Journal of Chemistry

The 2-methylpyridine, 2-diethylaminoethyl, and isopentyl linked a series of symmetric and unsymmetric benzimidazolium salts 2a-e were prepared and used in the synthesis of silver-N-heterocyclic carbene (NHC) complexes (3a-e). The Ru(II)-NHC complexes (4a-h) were synthesized via transmetalation reaction from 3a-e. 4a-h complexes were converted to Ru(II)-NHC.HCl complexes (5ah) by HCl solution of diethyl ether and characterized by different spectroscopic techniques such as 1H and 13C NMR, LC/MS-Q-TOF, FT-IR, elemental analysis, and melting point detection. We examined the effect of the structural difference of complexes on anticancer activity via different arenes and metal centers. Antiproliferative activity of 5a-h and 3a was tested …


Investigation Of Antibacterial Properties Of Polyacrylonitrile Fibers Modified By New Functional Groups And Silver Nanoparticles, Zeynep Okay, Meryem Kalkan Erdoğan, Başar Karaca, Meral Karakişla, Mehmet Saçak Jan 2022

Investigation Of Antibacterial Properties Of Polyacrylonitrile Fibers Modified By New Functional Groups And Silver Nanoparticles, Zeynep Okay, Meryem Kalkan Erdoğan, Başar Karaca, Meral Karakişla, Mehmet Saçak

Turkish Journal of Chemistry

This work reports the surface modification of polyacrylonitrile (PAN) fibers by graft copolymerization to ensure the decoration of homogenous and dense Ag nanoparticles. Two facile and subsequent modification processes resulted in a PAN fiber composite with an intact fibrous structure, sufficiently conductive for antistatic application and antibacterial activity. In the first step, some chemically attractive monomers and monomer mixtures, such as acrylic acid (AA), AA-itaconic acid (AA-IA), AA-acrylamide (AA-AAm), were introduced to the fiber surface by grafting. The grafting process was evidenced by FTIR, 1H-NMR, and SEM techniques. The second step aimed to form a chelate structure by Ag + …