DOCSLIB.ORG

Analysis of Polyethylenimine by Electrospray Ionization Mass

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Analysis of Polyethylenimine by Electrospray Ionization Mass ANALYSIS OF POLYETHYLENIMINE BY ELECTROSPRAY IONIZATION MASS SPECTROMETRY AND SIZE EXCLUSION CHROMATOGRAPHY By Jianghong Gu Submitted to the Faculty of the College of Arts and Sciences of American University in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy In Chemi /Dr. Monika Konakli'onaklieva Dean 0 1 the College of Arts and Sciences Dr. Milena Shahu Date 2005 American University Washington, D.C. 20016 AMERICAN UNIVERSITY LIBRARY Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number: 3187219 Copyright 2005 by Gu, Jianghong All rights reserved. INFORMATION TO USERS The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleed-through, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. ® UMI UMI Microform 3187219 Copyright 2006 by ProQuest Information and Learning Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. ProQuest Information and Learning Company 300 North Zeeb Road P.O. Box 1346 Ann Arbor, Ml 48106-1346 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. © COPYRIGHT by Jianghong Gu 2005 ALL RIGHTS RESERVED Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ANALYSIS OF POLYETHYLENIMINE BY ELECTROSPRAY IONIZATION MASS SPECTROMETRY AND SIZE EXCLUSION CHROMATOGRAPHY By Jianghong Gu ABSTRACT The efficient delivery of therapeutic genes into target cells or tissues is a critical goal in gene therapy. Polyethylenimine (PEI) has been widely proven to effectively transfer genes both in vitro and in vivo for various diseases. Studies have reported that PEFs efficiency as a gene delivery vehicle depends on its molecular weight and structure. However, commercial PEI has not been thoroughly characterized. Therefore the goal of this research is to develop methods to analyze commercial PEI, both linear and branched, through the use of electrospray ionization mass spectrometry (ESI-MS), size exclusion chromatography (SEC), and a combination of these two techniques. The method development involved the measurement of molecular weight distribution (MWD), the analysis of ion attachment, the determination of end groups, and the assessment of the degree of branching. The preliminary analysis of molecular weight distribution by ESI-MS showed that the MWD of each sample was found to be very similar. PEI analyzed by electrospray shows preferential ion attachments to most molecules. An ESI study with mono and ii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. divalent cations suggests the lithium cations appear to be the optimum candidate for cationization of ESI technique. The universal calibration concept was applied to analysis of molecular weight distribution by SEC. The result demonstrated the polymer structure played a dominant role in this study. Coupling ESI-MS with SEC technique enables the separation and characterization of complex polymer community. This study demonstrated the existence of two types of PEI molecules (non-cyclic and cyclic molecules). The end groups for these two types of PEI oligomers were obtained, respectively. To assess branching, imine derivatives of the PEI were prepared by reacting 7.5 equivalents of benzaldehyde and 4-fluorobenzaldehyde with PEI, respectively. ESI-MS spectra of the imine derivatives were compared and discussed. Analysis of PEI by ESI, SEC, and the combination of both techniques can provide valuable data, but the data is limited. For analysis of large PEI molecules, such as PEI- 1800 or higher, the MALDI-TOF-MS technique may be needed to overcome the detection limit of ESI-MS technique. 111 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ACKNOWLEDGEMENTS I would like to first thank and acknowledge a few persons who helped and supported me in my studies in the chemistry department of American University. I am greatly indebted to my advisor, Professor James E. Girard, for his patient instruction, greatest help, continuous support and encouragement in the past five years. I am also grateful to Dr. Monika Konaklieva and Dr. Milena Shahu for serving as members on my dissertation committee. Thank you, Dr. Konaklieva, for greatly supporting and helping me finish my research. Dr. Shahu, I thank you for always offering me encouragement and assistance. To the faculty, staff, and students in chemistry department, I would like to acknowledge the support, help, and friendship shown to me. Thanks to all of you for making our chemistry department a warm family. I also extend my appreciation to Robert Classon and Christopher Gilles at Shimadzu Scientific Instruments, Inc. They always provided me with very helpful suggestions and assistance related to my research whenever possible. Finally, I want to dedicate this dissertation to my family. Without their invaluable love, care, and support I couldn’t realize my ideal. Countless thanks to my parents, who keep encouraging and guiding me whenever I fall down. Special thanks to Liwei for his constant care and support. iv Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE OF CONTENTS ABSTRACT.................................................................................................................................ii ACKNOWLEDGEMENTS......................................................................................................iv LIST OF ILLUSTRATIONS....................................................................................................ix LIST OF TABLES...................................................................................................................xiii Chapter 1. INTRODUCTION................................................................................................................. 1 Polyethylenimine (PEI) ..............................................................................................6 Synthesis.................................................................................................... 6 Aziridine .............................................................................................8 Branched P E I .................................................................................. 10 Linear PE I ........................................................................................15 Chemical Properties................................................................................ 18 2. PEI TRANSFECTION CONSIDERATIONS..................................................................21 PEI/DNA Complexes ...............................................................................................21 Influencing Factors on PEI Transfection Efficiency ............................................ 26 Mechanism................................................................................................................31 3. PEI CHARACTERIZATION.............................................................................................33 Polymer Characterization ........................................................................................ 33 Previous Characterization of Polyethylenimine ....................................................35 v Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Statement of Dissertation ........................................................................................ 36 4. PRELIMINARY ANALYSIS OF PEI BY MASS SPECTROMETRY........................ 38 Introduction ...............................................................................................................38 MALDI-TOF MS....................................................................................40 Electrospray Ionization Mass Spectrometry ........................................42 Preliminary Determination of Molecular Weight Distribution ...........................45 Introduction ............................................................................................. 45 Experimental ........................................................................................... 45 Samples and Reagents ....................................................................45 Instrumentation ...............................................................................46 Procedures ............................................................................. 46 Results and Discussion ........................................................................... 46 Ion Attachment Analysis ......................................................................................... 48 Introduction ............................................................................................. 48 Experimental ........................................................................................... 56 Samples and Reagents ....................................................................56 Instrumentation ...............................................................................56
Load more

Recommended publications
  • Modification of Branched Polyethyleneimine Using Mesquite
    polymers Article Modification of Branched Polyethyleneimine Using Mesquite Gum for Its Improved Hemocompatibility Ana M. Pinilla-Torres 1 , Paola Y. Carrión-García 2, Celia N. Sánchez-Domínguez 2 , Hugo Gallardo-Blanco 3,* and Margarita Sánchez-Domínguez 1,* 1 Grupo de Química Coloidal e Interfacial Aplicada a Nanomateriales y Formulaciones, Centro de Investigación en Materiales Avanzados, S.C. (CIMAV, S.C.), Unidad Monterrey, Apodaca 66628, Mexico; [email protected] 2 Departamento de Bioquímica y Medicina Molecular, Facultad de Medicina, Universidad Autónoma de Nuevo León, Monterrey 64460, Mexico; [email protected] (P.Y.C.-G.); [email protected] (C.N.S.-D.) 3 Departamento de Genética, Facultad de Medicina, Universidad Autónoma de Nuevo León, Monterrey 64460, Mexico * Correspondence: [email protected] (H.G.-B.); [email protected] (M.S.-D.) Abstract: In the present study, the modification of branched polyethyleneimine (b-PEI) was car- ried out using mesquite gum (MG) to improve its hemocompatibility to be used in biomedi- cal applications. In the copolymer synthesis process (carboxymethylated mesquite gum grafted polyethyleneimine copolymer (CBX-MG-PEI), an MG carboxymethylation reaction was initially carried out (carboxymethylated mesquite gum (CBX-MG). Subsequently, the functionalization be- Citation: Pinilla-Torres, A.M.; tween CBX-MG and b-PEI was carried out using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide Carrión-García, P.Y.; (EDC) and N-hydroxysuccinimide (NHS) as crosslinking agents. The synthesis products were char- Sánchez-Domínguez, C.N.; acterized using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy Gallardo-Blanco, H.; (XPS), and thermogravimetric analysis (TGA). Thermogravimetric analysis showed that CBX-MG Sánchez-Domínguez, M.
    [Show full text]
  • Polyethylenimine-Derived Gene Carriers and Their Complexes with Plasmid DNA
    Polyethylenimine-derived Gene Carriers and their Complexes with plasmid DNA Design, Synthesis and Characterization Dissertation to obtain the Degree of Doctor of Natural Sciences (Dr. rer. nat.) from the Faculty of Chemistry and Pharmacy University of Regensburg Presented by Uta Lungwitz From Greifswald August 2006 To my family This work was carried out from October 2001 until August 2006 at the Department of Pharmaceutical Technology of the University of Regensburg. The thesis was prepared under the supervision of Prof. Dr. Achim Göpferich Submission of the Ph.D. application: July, 12th 2006 Date of examination: August, 10th 2006 Examination board: Chairman: Prof. Dr. S. Elz 1. Expert: Prof. Dr. A. Göpferich 2. Expert: Prof. Dr. A. Buschauer 3. Examiner: Prof. Dr. J. Heilmann Table of Contents Chapter 1 Introduction: Polyethylenimine-based non-viral gene 7 delivery systems Chapter 2 Goal of the thesis 55 Chapter 3 Synthesis of per-N-methylated polyethylenimine and its 61 application for non-viral gene delivery Chapter 4 Synthesis and characterization of poly (2-ethyl-2- 85 oxazoline) and linear polyethylenimine Chapter 5 Low molecular weight polyethylenimine-plasmid DNA 113 polyplexes: Particle properties and transfection efficacy Chapter 6 Degradable low molecular weight linear 147 polyethylenimines for non-viral gene transfer Chapter 7 Methoxy poly (ethylene glycol) – low molecular weight 181 linear polyethylenimine – derived copolymers enable polyplex shielding Chapter 8 Summary and conclusions 211 Appendix Abbreviations 219 Curriculum Vitae List of publications Acknoledgments 1. POLYETHYLENEIMINE-BASED NON- VIRAL GENE DELIVERY SYSTEMS U. Lungwitz, M. Breunig, T. Blunk, A. Göpferich Department of Pharmaceutical Technology, University of Regensburg, D- 93053 Regensburg, Germany European Journal of Pharmaceutics and Biopharmaceutics, 60 (2) 2005 p.
    [Show full text]
  • Selective Polymerization of 2-Isopropenyl-2-Oxazoline and Cross-Linking Reaction of the Polymers
    Polymer Journal, Vol. 3, No. 3, 307-314 (1972) Selective Polymerization of 2-Isopropenyl-2-oxazoline and Cross-linking Reaction of the Polymers Tsutomu KAGIYA and Takehisa MATSUDA Department of Hydrocarbon Chemistry, Faculty of Engineering, Kyoto University, Yoshida, Kyoto, Japan. (Received July 17, 1971) ABSTRACT: The selective polymerization of 2-isopropenyl-2-oxazoline possessing two polymerizable sites in molecule was studied. Due to a marked difference in .polymeriz­ ability between the isopropenyl and oxazoline groups, this monomer provided soluble linear polymers by radical and cationic polymerization. The former was poly(2-isopro­ penyl-2-oxazoline) with the oxazoline group as a side chain, and the latter N-meth­ acryloyl polyethylenimine. The cross-linking reactions of reactive pendant groups in both polymers, which resulted from the radical and cationic polymerizations, gave cross-linked, insoluble products. KEY WORDS Difunctional Monomer / 2-Isopropenyl-2-oxazoline / Selective Polymerization/ Poly(2-isopropenyl-2-oxazoline) / N-Meth­ acryloyl Polyethylenimine / Cross-linking Reaction / Gelation / 2-Isopropenyl-2-oxazoline is a difunctional for 15 hours according to the literature,8 and monomer possessing an isopropenyl group and purified by careful distillation under reduced oxazoline heterocycle as the polymerizable sites pressure [bp 50.5°C (17.5 mm)]. The identifica­ in molecule. It is reported by T. Kagiya, et al.,1 tion was carried out by the infrared and NMR and several other investigators2- 5 that 2-oxa­ spectra of the product. zolines can be polymerized by cationic catalysts Adipic acid as a cross-linker and a,a'-azobis­ such as stannic chloride or boron trifluoride isobutyronitrile (AIBN), which were commercial­ etherate to give N-acyl or N-aryloyl polyethyl­ ly available products (G.
    [Show full text]
  • Simple Modifications of Branched PEI Lead to Highly Efficient Sirna
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE 1448 Bioconjugate Chem. 2008, 19, 1448–1455 provided by Universität München: Elektronischen Publikationen Simple Modifications of Branched PEI Lead to Highly Efficient siRNA Carriers with Low Toxicity Arkadi Zintchenko,* Alexander Philipp, Ali Dehshahri, and Ernst Wagner Center for Drug Research, Department of Pharmacy, Pharmaceutical Biology-Biotechnology, and Center for NanoScience (CeNS), Ludwig-Maximilians-University, Butenandstr. 5-13, D-81377 Munich, Germany. Received February 19, 2008; Revised Manuscript Received May 7, 2008 Polymer carriers like PEI which proved their efficiency in DNA delivery were found to be far less effective for the applications with siRNA. In the current study, we generated a number of nontoxic derivates of branched PEI through modification of amines by ethyl acrylate, acetylation of primary amines, or introduction of negatively charged propionic acid or succinic acid groups to the polymer structure. The resulting products showed high efficiency in siRNA-mediated knockdown of target gene. In particular, succinylation of branched PEI resulted in up to 10-fold lower polymer toxicity in comparison to unmodified PEI. Formulations of siRNA with succinylated PEI were able to induce remarkable knockdown (80% relative to untreated cells) of target luciferase gene at the lowest tested siRNA concentration of 50 nM in Neuro2ALuc cells. The polyplex stability assay revealed that the efficiency of formulations which are stable in physiological saline is independent of the affinity of siRNA to the polymer chain. The improved properties of modified PEI as siRNA carrier are largely a consequence of the lower polymer toxicity.
    [Show full text]
  • Optimization Study of Polyethyleneimine Surface Coating for Microtip DNA Purification
    Optimization Study of Polyethyleneimine Surface Coating for Microtip DNA Purification Andrew Cairns A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science University of Washington 2013 Committee: Jae-Hyun Chung Amy Shen Kyong-Hoon Lee Program Authorized to Offer Degree: Mechanical Engineering ©Copyright 2013 Andrew Cairns University of Washington Abstract Optimization Study of Polyethyleneimine Surface Coating for Microtip DNA Purification Andrew Cairns Chair of the Supervisory Committee: Associate Professor Jae-Hyun Chung Mechanical Engineering DNA purification is a process to separate and extract DNA from various samples. As such, it is an initial step in molecular diagnostics, forensics, pharmacogenomics, and many other genetic analysis based disciplines. Current commercial solutions employ microfilters, centrifugation, or magnetic beads to extract DNA. Recently, silicon microtips have shown equivalent yield to the aforementioned methods, while using fewer reagents and shorter processing time. The working principle of the microtip system relies on dielectrophoretic force and capillary action to concentrate and bind DNA to the microtip surface. There remain two challenges associated with the microtip method: (1) increase efficacy of the process in the presence of a high concentration of inhibitors, such as in blood and (2) improve stability of the microtip surface chemistry during storage. In this thesis, we investigate a polymer film of Polyethyleneimine (PEI) as a potential surface layer to address these challenges. To evaluate the performance of PEI, a coating is applied to the microtips, and their purification performance is tested in a variety of conditions. The operation parameters including curing temperature, capture time, elution time, and elution temperature are optimized.
    [Show full text]
  • (12) Patent Application Publication (10) Pub. No.: US 2010/0197888 A1 Adib Et Al
    US 2010O197888A1 (19) United States (12) Patent Application Publication (10) Pub. No.: US 2010/0197888 A1 Adib et al. (43) Pub. Date: Aug. 5, 2010 (54) METHOD FOR MANUFACTURING LINEAR Related U.S. Application Data POLYETHYLENIMINE (PED FOR TRANSFECTION PURPOSE AND LINEAR PE (60) Provisional application No. 60/952,993, filed on Jul. OBTANED WITH SUCH METHOD 31, 2007. Publication Classification (75) Inventors: Abdennaji Adib, Illkirch (FR): (51) Int. Cl. Fabrice Stock, Lingolsheim (FR): C08G 73/06 (2006.01) Patrick Erbacher, Illkirch (52) U.S. Cl. ........................................................ 528/423 Graffenstaden (FR) (57) ABSTRACT Correspondence Address: The invention concerns a method of synthesising and prepar BANNER & WITCOFF, LTD. ing linear polyethylenimine (PEI) for use as a transfection 1100 13th STREET, N.W., SUITE 1200 vector, and the product obtained with such a method. It com prises drying a monomer 2-ethyl-2-oxazoline and polymeris WASHINGTON, DC 20005-4051 (US) ing said monomer for obtaining poly (2-ethyl-2-oxazoline) (PEOX) by: using acetonitrile as solvent, adding a dried ini (73) Assignee: Polyplus Transfection, Ilkirch tiator of the reaction of polymerisation, and mixing them Graffenstaden (FR) altogether, purifying said obtained PEOX by evaporation, while performing at least three times successive washing/ (21) Appl. No.: 12/671,312 precipitation steps with methanol and diethyl ether and cor responding filtrations, in order to obtain (i), by performing (22) PCT Fled: Jul. 31, 2008 1H-NMR tests, correct identification of said PEOX polymer, confirmation of absence of monomer to a level <1.0% and (86) PCT NO.: PCT/B2O08/OO2339 confirmation of absence of solvent to a level <5.0% and (ii), by performing Gel Permeation Chromatography, a mean of S371 (c)(1), molecular weight (Mw)>23,000 Da and polydispersity (Mw/ (2), (4) Date: Apr.
    [Show full text]
  • Base Strength-Reactivity Effects in Polyethylenimine Esterolysis Reactions
    BASE STRENGTH-REACTIVITY EFFECTS IN POLYETHYLENIMINE ESTEROLYSIS REACTIONS BY CURTIS S. LEGE A DISSERTATION PRESENTED TO THE GRADUATE COUNCIL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY UNIVERSITY OF FLORIDA 1979 TO MY WIFE AND DAUGHTER JOE ANN AND SPRING ACKNOWLEDGMENTS The author wishes to express his appreciation to his research director, James A. Deyrup, for his thoughtful guidance and criticism as well as his encouragement of individual creativity in problem selection and pursuit. The author is further indebted to Professor John A. Zoltewicz for the many helpful discussions and use of equipment. The author wishes to thank the faculty and staff of the University of Florida and his fellow graduate students for an enjoyable and fruitful experience. Special thanks are extended to Tom Baugh and Eric Langenmeyer for their friendship and advice. The author is especially indebted to his wife who has provided not only encouragement throughout but also has made considerable contribution to the preparation of this dissertation. TABLE OF CONTENTS Page ACKNOWLEDGMENTS _ _ m LIST OF TABLES vii LIST OF FIGURES viii ABSTRACT x CHAPTER I POLYMER ESTEROLYSIS REACTIONS: DISCUSSION AND PROPOSAL 1 Introduction \ Discussion 2 Mechanism of Polymer Esterolysis Reactions 2 Polymer Catalyzed Hydrolysis 8 Summary n Proposal 12 Introduction 12 Nucleophiles 12 Polymer 13 Ester 15 Results 16 CHAPTER II AMINOLYSIS OF P-NITROPHENYL ESTERS BY DODECYL POLYETHYLENIMINE 2 2 Results and Discussion 22 Characterization 22 Basicity of PEI-D-NH -HC1 2 25 Kinetic Analysis....; 26 Eronsted Relationship 34 Summary 43 IV CHAPTER III HYDROLYSIS OF P-NITROPHENYL ESTERS CATALYZED BY POLYMER BOUND HETEROCYCLES .
    [Show full text]
  • SPECIFIC and EFFICIENT in VIVO DELIVERY of DNA and Sirna by POLYETHYLENIMINE and ITS DERIVATIVES
    SPECIFIC AND EFFICIENT IN VIVO DELIVERY OF DNA AND siRNA BY POLYETHYLENIMINE AND ITS DERIVATIVES by MASSACHUSETTS INSTITUTE OF TECHNOLOGY JENNIFER A. FORTUNE SEP 2 22010 B.A. Chemistry Wheaton College, 2003 LIBRARIES Submitted to the Department of Chemistry in Partial Fulfillment of the Requirements for the Degree of ARCHVES Doctor of Philosophy in Biological Chemistry at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY September 2010 @ 2010 Massachusetts Institute of Technology All rights reserved Signature of Author:. Department of Chemistry August 3, 2010 Certified by: Alexander M. Klibanov Novartis ChairProfessor of Chemistry and Bioengineering Thesis Supervisor Accepted by:. Robert W. Field Haslam and Dewey Professor of Chemistry Chairman,Departmental Committee on Graduate Students This Doctoral Thesis has been examined by a committee of the Department of Chemistry as follows: JoAnne Stubbe Novartis Professorof Chemistry and Professor of Biology Thesis Chair Alexander M. Klibanov Novartis Chair Professor of Chemistry and Bioengineering Thesis Supervisor John M.Essigmann William R. and Betsy P. Leitch Professor of Chemistry andiologicalEngineering SPECIFIC AND EFFICIENT IN VIVO DELIVERY OF DNA AND siRNA BY POLYETHYLENIMINE AND ITS DERIVATIVES by JENNIFER A. FORTUNE Submitted to the Department of Chemistry on August 3, 2010 in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in Biological Chemistry ABSTRACT Linear polyethylenimine (PEI) is the "gold standard" of polycationic gene delivery vectors. However, little focus has been placed on enhancing or understanding the specificity of PEI- mediated gene delivery. Herein we evaluated the effect of chemical modification on the specificity of PEI-mediated nucleic acid delivery. We found that low molecular weight PEI (2 kDa) does not mediate efficient gene expression while high molecular weight (> 87 kDa) leads to toxicity.
    [Show full text]
  • Temperature and Ph Responsive Polyethylenimine Systems As Potential Nonviral Gene Vectors
    Wright State University CORE Scholar Browse all Theses and Dissertations Theses and Dissertations 2010 Temperature and pH Responsive Polyethylenimine Systems as Potential Nonviral Gene Vectors S. Chad Skidmore Wright State University Follow this and additional works at: https://corescholar.libraries.wright.edu/etd_all Part of the Chemistry Commons Repository Citation Skidmore, S. Chad, "Temperature and pH Responsive Polyethylenimine Systems as Potential Nonviral Gene Vectors" (2010). Browse all Theses and Dissertations. 1011. https://corescholar.libraries.wright.edu/etd_all/1011 This Thesis is brought to you for free and open access by the Theses and Dissertations at CORE Scholar. It has been accepted for inclusion in Browse all Theses and Dissertations by an authorized administrator of CORE Scholar. For more information, please contact [email protected]. TEMPERATURE AND pH RESPONSIVE POLYETHYLENIMINE SYSTEMS AS POTENTIAL NONVIRAL GENE VECTORS A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science By S. CHAD SKIDMORE B.A., Case Western Reserve University, 2008 2010 Wright State University School of Graduate Studies July 26, 2010 I HEREBY RECOMMEND THAT THE THESIS PREPARED UNDER MY SUPPERVISION BY S. Chad Skidmore ENTITLED Temperature and pH Responsive Polyethylenimine Systems as Potential Nonviral Gene Vectors BE ACCEPTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF Master of Science. _______________________________ Eric Fossum, Ph.D. Thesis Advisor _______________________________ Kenneth Turnbull, Ph.D. Department Chair Committee on Final Examination _______________________________ Eric Fossum, Ph.D. _______________________________ Kenneth Turnbull, Ph.D. _______________________________ Ioana Pavel, Ph.D. _______________________________ Andrew T. Hsu, Ph.D. Dean, School of Graduate Studies Abstract Skidmore, S.
    [Show full text]
  • Nanoparticles of Quaternary Ammonium Polyethylenimine Derivatives for Application in Dental Materials
    polymers Review Nanoparticles of Quaternary Ammonium Polyethylenimine Derivatives for Application in Dental Materials Marta Chrószcz * and Izabela Barszczewska-Rybarek Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, 44-100 Gliwice, Poland; [email protected] * Correspondence: [email protected]; Tel.: +48-(32)-2371793 Received: 9 September 2020; Accepted: 28 October 2020; Published: 30 October 2020 Abstract: Various quaternary ammonium polyethylenimine (QA-PEI) derivatives have been synthesized in order to obtain nanoparticles. Due to their antibacterial activity and non-toxicity towards mammalian cells, the QA-PEI nanoparticles have been tested extensively regarding potential applications as biocidal additives in various dental composite materials. Their impact has been examined mostly for dimethacrylate-based restorative materials; however, dental cements, root canal pastes, and orthodontic adhesives have also been tested. Results of those studies showed that the addition of small quantities of QA-PEI nanoparticles, from 0.5 to 2 wt.%, led to efficient and long-lasting antibacterial effects. However, it was also discovered that the intensity of the biocidal activity strongly depended on several chemical factors, including the degree of crosslinking, length of alkyl telomeric chains, degree of N-alkylation, degree of N-methylation, counterion type, and pH. Importantly, the presence of QA-PEI nanoparticles in the studied dental composites did not negatively impact the degree of conversion in the composite matrix, nor its mechanical properties. In this review, we summarized these features and functions in order to present QA-PEI nanoparticles as modern and promising additives for dental materials that can impart unique antibacterial characteristics without deteriorating the products’ structures or mechanical properties.
    [Show full text]
  • Starch Xanthate-Polyethylenimine Reaction Mechanisms
    3693 JOCR:-AL OF POLY:\IER SCIE:-CE, Polymer Chemistry Edition YOL. 13. 1-HI-1-156 iIQ75l Starch Xanthate-Polyethylenimine Reaction Mechanisms :'If. E. CARB, B. T. HOFRElTER, and C. H.. H.USSELL, Northern Re(liollal Research Laboratory, Auricultural Research Service, C.S. Department of Ayriculture. Peoria, Illinois 6'16'04- Synopsis Thl' C'hemiC'al nature of starch xanthate (SX)-polyethylenimine (PEl) reaction produC'ts ha.~ been studied berause of their effertiveness as wet-end additives for im­ prllving strength properties of paper. :\lodel rompounds, in ronjunction with ultra­ vitllct, infrared, and chemical analyses, served to elucidate SX-PEl reaction mecha­ nisms. Aqueous solutions of ~X (degree:s of :sub:;titution O.l-D.;,) were titrated with PEl at pI! :.-i (2,i-:lQoC) to form SX-PEl !locrulent precipitate:s that were determined til hl' polyelectrolyte complexes. However. when :solutions of SX-PEl were kept at pH Ill-I:!. produc·ts were formed that induded dithiocarbamic acid salts in major quantities, PEl thiourea.-, and minor quantities of O-:starch PEl thionrarbamate. Acid precipita­ tion of thesl' ~X-PEI polymeriC' reaction products from their alkaline solutions, which ('Ilntained residual xanthate and PEl. also yielded polyelectrolyte complexe:;. :\lodel ,.'·-tems suggest th:lt PEl thiurum disulfide and starch xanthide, pos:;ible products of air lOxidal iOII, ('ould he present in minor amount:; and would react rapidly with PEl to yield thi'l\lreas and thioncarbamates, respectively. Apparently, mixtures of xanthate and alnin!' gave (1) dithioearbamic aeid salts from both xanthate groups and CS, (decom­ positilln from xanthate), (2) thioureas from both dithioearbamic aeid salts and thiuram eli,ulfide, and (;l) thionearbamates, principally from xanthate a:s opposed to xanthide.
    [Show full text]
  • Full Deacylation of Polyethylenimine Dramatically Boosts Its Gene Delivery Efficiency and Specificity to Mouse Lung
    Full deacylation of polyethylenimine dramatically boosts its gene delivery efficiency and specificity to mouse lung Mini Thomas*, James J. Lu†‡, Qing Ge†, Chengcheng Zhang§, Jianzhu Chen†, and Alexander M. Klibanov*¶ *Department of Chemistry and Division of Biological Engineering, †Center for Cancer Research and Department of Biology, ‡Department of Chemical Engineering, and §Whitehead Institute of Biomedical Research, Massachusetts Institute of Technology, Cambridge, MA 02139 Contributed by Alexander M. Klibanov, March 12, 2005 High-molecular-mass polyethylenimines (PEIs) are widely used ethylenimines (PEIs) (14, 15), are inferior to their viral coun- vectors for nucleic acid delivery. We found that removal of the terparts in the efficiency and specificity of nucleic acid delivery. residual N-acyl moieties from commercial linear 25-kDa PEI en- In the present study, we show that commercial preparations of hanced its plasmid DNA delivery efficiency 21 times in vitro, as well linear PEI (molecular mass ϭ 25 kDa) contain residual N-acyl as 10,000 times in mice with a concomitant 1,500-fold enhance- groups, which severely handicap nucleic acid transfection. Re- ment in lung specificity. Several additional linear PEIs were syn- moval of the residual N-acyl groups dramatically enhances DNA thesized by acid-catalyzed hydrolysis of poly(2-ethyl-2-oxazoline), transfection efficiency of this PEI. Consistent with these find- yielding the pure polycations. PEI87 and PEI217 exhibited the ings, three additional linear PEIs, synthesized ab initio in the highest efficiency in vitro: 115-fold and 6-fold above those of the nonacylated form, exhibited remarkable DNA and short inter- commercial and deacylated PEI25s, respectively; moreover, PEI87 fering RNA (siRNA) delivery efficiency and specificity.
    [Show full text]