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Amplification of Oxidative Stress by a Dual Stimuli-Responsive Hybrid Drug
ARTICLE Received 11 Jul 2014 | Accepted 12 Mar 2015 | Published 20 Apr 2015 DOI: 10.1038/ncomms7907 Amplification of oxidative stress by a dual stimuli-responsive hybrid drug enhances cancer cell death Joungyoun Noh1, Byeongsu Kwon2, Eunji Han2, Minhyung Park2, Wonseok Yang2, Wooram Cho2, Wooyoung Yoo2, Gilson Khang1,2 & Dongwon Lee1,2 Cancer cells, compared with normal cells, are under oxidative stress associated with the increased generation of reactive oxygen species (ROS) including H2O2 and are also susceptible to further ROS insults. Cancer cells adapt to oxidative stress by upregulating antioxidant systems such as glutathione to counteract the damaging effects of ROS. Therefore, the elevation of oxidative stress preferentially in cancer cells by depleting glutathione or generating ROS is a logical therapeutic strategy for the development of anticancer drugs. Here we report a dual stimuli-responsive hybrid anticancer drug QCA, which can be activated by H2O2 and acidic pH to release glutathione-scavenging quinone methide and ROS-generating cinnamaldehyde, respectively, in cancer cells. Quinone methide and cinnamaldehyde act in a synergistic manner to amplify oxidative stress, leading to preferential killing of cancer cells in vitro and in vivo. We therefore anticipate that QCA has promising potential as an anticancer therapeutic agent. 1 Department of Polymer Á Nano Science and Technology, Polymer Fusion Research Center, Chonbuk National University, Backje-daero 567, Jeonju 561-756, Korea. 2 Department of BIN Convergence Technology, Chonbuk National University, Backje-daero 567, Jeonju 561-756, Korea. Correspondence and requests for materials should be addressed to D.L. (email: [email protected]). NATURE COMMUNICATIONS | 6:6907 | DOI: 10.1038/ncomms7907 | www.nature.com/naturecommunications 1 & 2015 Macmillan Publishers Limited. -
With Organic Oxalates Ching Ching (Chua) Ong Iowa State University
Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1969 Part I. Gas phase pyrolysis of organic oxalates, Part II. Reactions of chromium(II) with organic oxalates Ching Ching (Chua) Ong Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Organic Chemistry Commons Recommended Citation Ong, Ching Ching (Chua), "Part I. Gas phase pyrolysis of organic oxalates, Part II. Reactions of chromium(II) with organic oxalates" (1969). Retrospective Theses and Dissertations. 4679. https://lib.dr.iastate.edu/rtd/4679 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. This dissertation has been microfilmed exactly as received 69-15,637 ONG, Ching Ching (Chua), 1941- PART I. GAS PHASE PYROLYSIS OF ORGANIC OXALATES. PART II. REACTIONS OF CHROMIUM (II) WITH ORGANIC OXALATES. Iowa State University, Ph.D., 1969 Chemistry, organic University Microfilms, Inc., Ann Arbor, Michigan PART I. GAS PHASE PYROLYSIS OF ORGANIC OXALATES PART II. REACTIONS OF CHROMIUM(II) WITH ORGANIC OXALATES by Ching Ching (Chua) Ong A Dissertation Submitted to the Graduate Faculty in Partial Fulfillment of Tîie Requirements for the Degree of DOCTOR OF PHILOSOPHY Major Subject: Organic Chemistry Approved: Signature was redacted for privacy. In Charge of Major Work Signature was redacted for privacy. Signature was redacted for privacy. Iowa State University Ames, Iowa 1969 ii TABLE OF CONTENTS Page PART I. -
A) Single-Beam
Lecture 2 Spectrophotometer Spectrophotometry is the basis for many of the instruments used in clinical chemistry. The primary reasons for this are ease of measurement, satisfactory accuracy and precision, and the suitability of spectrophotometric techniques to use in automated instruments. Spectrophotometer measures light absorption by a liquid substance at various wavelengths. The Components of unknown material can be determined, or the concentration of a number of known substances can be measured. Types of Spectrophotometer Ultraviolet (UV) Spectrophotometers. Uses ultraviolet light of wave lengths from 200 nm to 350 nm. light) of wave lengths from 350 nm to 700 nm. Spectrophotometer Block Diagram a) Single-beam b) Double-beam Most common Spectrophotometer 1. Photodiode 2. Connection wire 3. Lamp 4. Filter/Detector 5. On/Off switch and zero transmission adjustment knob 6. Wavelength selector/Readout 7. Sample chamber 8. Transmittance/absorbance control 9. Absorbance/Transmittance scale 1. Light Sources Tungsten lamp: Vis. near IR (320 nm~2500 nm) Deuterium arc lamp: UV (200~400 nm) Uses a tungsten filament and anode placed on opposite sides of a nickel box structure designed to produce the best output spectrum. Unlike tungsten lamps, the filament is not the source of light in deuterium lamps. Instead an arc is created from the filament to the anode. The arc created excites the molecular deuterium contained within the bulb to a higher energy state. The deuterium then emits light as it transitions back to its initial state Its continuous spectrum is only from 180 nm to 370 nm. Light Intensity of Tungsten and Deuterium lamps A problem with tungsten lamps is that, during operation, the tungsten progressively vaporizes from the filaments and condenses on the glass envelope. -
9.2.3.7 Retention Parameters in Column Chromatography
9.2.3.7 Retention Parameters in Column Chromatography Retention parameters may be measured in terms of chart distances or times, as well as mobile phase volumes; e.g., tR' (time) is analogous to VR' (volume). If recorder speed is constant, the chart distances are directly proportional to the times; similarly if the flow rate is constant, the volumes are directly proportional to the times. Note: In gas chromatography, or in any chromatography where the mobile phase expands in the column, VM, VR and VR' represent volumes under column outlet pressure. If Fc, the carrier gas flow rate at the column outlet and corrected to column temperature (see Flow Rate), is used in calculating the retention volumes from the retention time values, these correspond to volumes at column temperatures. The various conditions under which retention volumes (times) are expressed are indicated by superscripts: thus, a prime ('; as in VR') refers to correction for the hold-up volume (and time) while a circle (º; as in VRº) refers to correction for mobile-phase compression. In the case of the net retention volume (time) both corrections should be applied: however, in order not to confuse the symbol by the use of a double superscript, a new symbol (VN, tN) is used for the net retention volume (time). Hold-up Volume (Time) (VM, tM ) The volume of the mobile phase (or the corresponding time) required to elute a component the concentration of which in the stationary phase is negligible compared to that in the mobile phase. In other words, this component is not retained at all by the stationary phase. -
Modelo Normalizado De Ficha Para Asignaturas
Subject Guide SEPARATION PROCESSES Academic year: 2018-2019 (Last actualitation 10/01/2019) MODULE CONTENT YEAR TERM CREDITS TYPE Complements of Separation processes 3rd 2nd 6 ECTS Optative Formation LECTURERS CONTACT INFORMATION Department of Physical Chemistry. Faculty of Pharmacy. Campus Universitario de Cartuja. 18071 – Granada. Telephone: 958243829 Email: [email protected] , [email protected] María Eugenia García Rubiño TUTORSHIPS Delia Miguel Álvarez García Rubiño, María Eugenia (Room 194) Monday and Wednesday: 9:30−12:30 Miguel Álvarez, Delia (Room 197) Monday and Wednesday: 9:30−12:30 DEGREE WITHIN THE SUBJECT IS TAUGH Pharmacy PRERREQUISITES and/or RECOMMENDATIONS Proper knowledge about: Instrumentals Techniques General Chemistry Basic Physics and Physical Chemistry Organic Chemistry Inorganic Chemistry Biochemistry DETAILED SUBJECT SYLLABUS THEORETICAL SYLLABUS Página 1 UNIT 1. Introduction to chromatography. History. Concept of chromatography. Classification. Equilibrium distribution. Linear isotherms. Distribution parameters. Linear elution chromatography. Retention parameters. Migration. UNIT 2. Theories of chromatography. Theory of plates. Column efficiency. Kinetic theory. General equation. Differences between c. G. And c. L. Resolution. Retention time. Optimum efficiency conditions of the column. Gradient elution and temperature programming. Applications. The calibration method using standards. Standardization areas. Internal standard. UNIT 3. Plane chromatography. CP and CCF. How the separation is performed. Performance characteristics. Variables affecting the rf. Qualitative and quantitative determinations. UNIT 4. Gas chromatography. Gc retention volume, specific volume. Pharmaceutical applications. Qualitative interpretation of a chromatogram. Relative retention. Oster relationship. Kovats retention index. UNIT 5. Gas chromatography instrumentation. Carrier gas. Sample injection. Columns. Stationary phases. Thermal conductivity detectors, flame ionization, electron capture, atomic emission. Attachment with mass spectrometry. UNIT 6. -
UV-VIS Nomenclature and Units
IN804 Info Note 804: UV-VIS Nomenclature and Units Ultraviolet-visible spectroscopy or ultraviolet-visible spectrophotometry (UV/VIS) involves the spectroscopy of photons in the UV-visible region. It uses light in the visible and adjacent near ultraviolet (UV) and near infrared (NIR) ranges. In this region of the electromagnetic spectrum, molecules undergo electronic transitions. This technique is complementary to fluorescence spectroscopy, in that fluorescence deals with transitions from the excited state to the ground state, while absorption measures transitions from the ground state to the excited state. UV/VIS is based on absorbance. In spectroscopy, the absorbance A is defined as: (1) where I is the intensity of light at a specified wavelength λ that has passed through a sample (transmitted light intensity) and I is the intensity of the light before it enters the sample or 0 incident light intensity. Absorbance measurements are often carried out in analytical chemistry, since the absorbance of a sample is proportional to the thickness of the sample and the concentration of the absorbing species in the sample, in contrast to the transmittance I / I of a 0 s ample, which varies exponentially with thickness and concentration. The Beer-Lambert law is used for concentration determination. The term absorption refers to the physical process of absorbing light, while absorbance refers to the mathematical quantity. Also, absorbance does not always measure absorption: if a given sample is, for example, a dispersion, part of the incident light will in fact be scattered by the dispersed particles, and not really absorbed. Absorbance only contemplates the ratio of transmitted light over incident light, not the mechanism by which light intensity decreases. -
UV-Vis) Absorption Vs
授課教師: Professor 吳逸謨 教授 Warning: Copyrighted by textbook publisher. Do not use outside class. Principles of Instrumental Analysis Section III – Molecular Spectroscopy Chapter 13 Introduction to Ultraviolet-Visible Absorption Spectrometry + Chapter 14 Applications of Ultraviolet-Visible Absorption Spectrometry Reference: p. 423, Visible and UV spectra, in “Organic Chemistry” textbook – Solomons, 3rd Ed] 1 Molecular Spectroscopy Ultraviolet–visible (UV-Vis) absorption vs. fluorescence Spectroscopy Ultraviolet–visible spectroscopy or ultraviolet-visible spectrophotometry (UV-Vis or UV/Vis) refers to absorption spectroscopy or reflectance spectroscopy in the ultraviolet-visible spectral region. This means it uses light in the visible and adjacent (near-UV and near- infrared [NIR]) ranges. The absorption or reflectance in the visible range directly affects the perceived color of the chemicals involved. In this region of the electromagnetic spectrum, molecules undergo electronic transitions. Fluorescence spectroscopy is based on molecular emission: The “UV-Vis” technique is complementary to fluorescence spectroscopy, in that fluorescence deals with transitions from the excited state to the ground state, while UV-Vis absorption measures transitions from the ground state to the excited state.[1] 2 (2007/3) UV-Vis Spec 儀器 -實驗課 3 FIGURE 6-3 Regions of the electromagnetic spectrum. (For UV-Vis, λ = 100~500 nm, 500~1000 nm) 4 Ch6 An Introduction to Spectrometric Methods P.135 Apendix: Chap. 7E - Radiation Transducers p. 191 Read the texts in Chap. 7 7E-2 Photon Transducers for optical spectroscopy – Barrier-Layer Photovoltaic Cells – Vacuum Phototubes – Photomultiplier tubes (PMT), picture on p. 195 – Silicon Photodiodes (Fig. 7-32) [semiconductor type] [A silicon photodiode transducer consists of a reverse- biased p-n junction.] (The latter two types of transducers are more commonly used in UV-Vis.) – We will discuss more details later. -
Reproducibility of Retention Indices Examining Column Type
Graduate Theses, Dissertations, and Problem Reports 2013 Reproducibility of Retention Indices Examining Column Type Amanda M. Cadau West Virginia University Follow this and additional works at: https://researchrepository.wvu.edu/etd Recommended Citation Cadau, Amanda M., "Reproducibility of Retention Indices Examining Column Type" (2013). Graduate Theses, Dissertations, and Problem Reports. 440. https://researchrepository.wvu.edu/etd/440 This Thesis is protected by copyright and/or related rights. It has been brought to you by the The Research Repository @ WVU with permission from the rights-holder(s). You are free to use this Thesis in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you must obtain permission from the rights-holder(s) directly, unless additional rights are indicated by a Creative Commons license in the record and/ or on the work itself. This Thesis has been accepted for inclusion in WVU Graduate Theses, Dissertations, and Problem Reports collection by an authorized administrator of The Research Repository @ WVU. For more information, please contact [email protected]. Reproducibility of Retention Indices Examining Column Type Amanda M. Cadau Thesis submitted to the Eberly College of Arts and Sciences at West Virginia University in partial fulfillment of the requirements for the degree of Master of Science in Forensic and Investigative Science Suzanne Bell, Ph.D., Chair Glen Jackson, Ph.D. Keith Morris, Ph.D. Department of Forensic and Investigative Science Morgantown, West Virginia 2013 Keywords: Retention Index, Kovats Retention Index, GC/MS, Drugs of Abuse ABSTRACT Reproducibility of Retention Indices Examining Column Type Amanda M. -
Replacing the AMOR with the Minidoas in the Ammonia Monitoring Network in the Netherlands
Atmos. Meas. Tech., 10, 4099–4120, 2017 https://doi.org/10.5194/amt-10-4099-2017 © Author(s) 2017. This work is distributed under the Creative Commons Attribution 3.0 License. Replacing the AMOR with the miniDOAS in the ammonia monitoring network in the Netherlands Augustinus J. C. Berkhout1, Daan P. J. Swart1, Hester Volten1, Lou F. L. Gast1, Marty Haaima1, Hans Verboom1,a, Guus Stefess1, Theo Hafkenscheid1, and Ronald Hoogerbrugge1 1National Institute for Public Health and the Environment (RIVM), P.O. Box 1, 3720 BA Bilthoven, the Netherlands anow at: Royal Netherlands Meteorological Institute (KNMI), P.O. Box 201, 3730 AE De Bilt, the Netherlands Correspondence to: A. J. C. Berkhout ([email protected]) Received: 16 October 2016 – Discussion started: 3 March 2017 Revised: 31 August 2017 – Accepted: 16 September 2017 – Published: 2 November 2017 Abstract. In this paper we present the continued develop- nitrogen oxides or sulfur dioxide. These aerosols contribute ment of the miniDOAS, an active differential optical ab- to the total burden of particulate matter and may have public sorption spectroscopy (DOAS) instrument used to measure health effects (Fischer et al., 2015). When deposited on na- ammonia concentrations in ambient air. The miniDOAS has ture areas, ammonia causes acidification and eutrophication, been adapted for use in the Dutch National Air Quality Mon- leading to a loss of biodiversity. Intensive animal husbandry itoring Network. The miniDOAS replaces the life-expired leads to high ammonia emissions in the Netherlands. Hence, continuous-flow denuder ammonia monitor (AMOR). From it is of great importance to have a correct understanding of September 2014 to December 2015, both instruments the sources and sinks of ammonia in the Netherlands and of measured in parallel before the change from AMOR to the processes that determine ammonia emissions to the air, miniDOAS was made. -
Fundamentals of Modern UV-Visible Spectroscopy
Fundamentals of modern UV-visible spectroscopy Primer Tony Owen Copyright Agilent Technologies 2000 All rights reserved. Reproduction, adaption, or translation without prior written permission is prohibited, except as allowed under the copyright laws. The information contained in this publication is subject to change without notice. Printed in Germany 06/00 Publication number 5980-1397E Preface Preface In 1988 we published a primer entitled “The Diode-Array Advantage in UV/Visible Spectroscopy”. At the time, although diode-array spectrophotometers had been on the market since 1979, their characteristics and their advantages compared with conventional scanning spectrophotometers were not well-understood. We sought to rectify the situation. The primer was very well-received, and many thousands of copies have been distributed. Much has changed in the years since the first primer, and we felt this was an appropriate time to produce a new primer. Computers are used increasingly to evaluate data; Good Laboratory Practice has grown in importance; and a new generation of diode-array spectrophotometers is characterized by much improved performance. With this primer, our objective is to review all aspects of UV-visible spectroscopy that play a role in obtaining the best results. Microprocessor and/or computer control has taken much of the drudgery out of data processing and has improved productivity. As instrument manufacturers, we would like to believe that analytical instruments are now easier to operate. Despite these advances, a good knowledge of the basics of UV-visible spectroscopy, of the instrumental limitations, and of the pitfalls of sample handling and sample chemistry remains essential for good results. -
Phd Thesis Aims at Developing Self-Reporting Systems Based on Chemiluminescence for Tracking of Bond Formation and Cleavage
QUEENSLAND UNIVERSITY OF TECHNOLOGY FACULTY OF SCIENCE SCHOOL OF CHEMISTRY AND PHYSICS SUBMITTED IN FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF Doctor of Philosophy Chemiluminescent Self-Reporting Macromolecular Transformation Fabian R. Bloesser MSc Chemistry 2021 “We scholars like to think science has all the answers, but in the end it’s just a bunch of unprovable nonsense.” Sorcerio, in Matt Groening’s Disenchantment, S1E3 Statement of Original Authorship The work contained in this thesis has not been previously submitted to meet require- ments for an award at this or any other higher education institution. To the best of my knowledge and belief, the thesis contains no material previously published or written by another person except where due reference is made. 21 June 2021 QUT Verified Signature ...................................................................... (Fabian R. Bloesser) Abstract Self-reporting systems play a major role in the detection and localisation of damages and mechanical stress in materials, the formation and reversion of networks, the detection of drug release as well as the presence of toxins in cells. While a change in colour or fluorescence have been the detection mode of choice in the past, chemiluminescence (CL) systems have attracted increasing interest in the past years, as CL provides a high sensitivity, allows for real-time monitoring and quantification, and does usually not require sophisticated equipment. Therefore, the current study focuses on the development of self-reporting CL systems for -
Practical Retention Index Models of OV-101, DB-1, DB-5, and DB-Wax for flavor and Fragrance Compounds$
ARTICLE IN PRESS LWT 41 (2008) 951–958 www.elsevier.com/locate/lwt Practical retention index models of OV-101, DB-1, DB-5, and DB-Wax for flavor and fragrance compounds$ K.L. Goodnerà USDA, ARS, Citrus & Subtropical Products Lab, Winter Haven, FL 33884, USA Received 24 April 2007; received in revised form 5 July 2007; accepted 16 July 2007 Abstract High-quality regression models of gas chromatographic retention indices were generated for OV-101 (R ¼ 0.997), DB-1 (R ¼ 0.998), DB-5 (R ¼ 0.997), and DB-Wax (R ¼ 0.982) using 91, 57, 94, and 102 compounds, respectively. The models were generated using a second-order equation including the cross product utilizing two easily obtained variables, boiling point and the log octanol-water coefficient. Additionally, a method for determining outlier data (the GOodner Outlier Determination (GOOD) method) is presented, which is a combination of several outlier tests and is less prone to discarding legitimate data. Published by Elsevier Ltd. on behalf of Swiss Society of Food Science and Technology. 0 1. Introduction trðNÞ is the adjusted retention time of the larger alkane (Harris, 1987). Determination of unknowns in gas chromatography There are compilations of retention indices on different (GC) requires two independent forms of identification such stationary phase columns for many compounds, which are as the retention time on two different chromatographic useful for identifying unknown compounds. However, columns, retention time and mass spectral match, or these compilations are not complete and situations arise retention time and aromatic match (Harris, 1987). Because where one has a potential identification from a mass retention times vary depending on the temperature spectral match, but no information on retention index.