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Malešič J, Kraševec I, Kralj Cigić I. Determination of Cellulose Degree of Polymerization in Historical Papers with High Lignin Content. Polymers (Basel) 2021; 13:polym13121990. [PMID: 34204589 PMCID: PMC8233719 DOI: 10.3390/polym13121990] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/11/2021] [Accepted: 06/15/2021] [Indexed: 12/01/2022] Open
Abstract
Determination of cellulose degree of polymerization (DP) is one of the most commonly used methods in paper degradation studies, performed either by a standardized method using viscometry (as average degree of polymerization (DPv)) or size-exclusion chromatography (SEC) (as weight average molecular mass (Mw)). Due to the insolubility of papers with high lignin content in cupriethylenediamine (CED), such as groundwood papers, viscometric determination is not possible; therefore, pretreatment is required to allow subsequent dissolution of the papers. In this study, the pretreatment of historical papers containing groundwood with sodium chlorite in acetic acid was investigated, which enables dissolution of the paper samples in CED and determination of the cellulose average degree of polymerization by viscometry (DPv). Kappa number was determined to estimate the lignin content in the papers. The suitability of SEC UV-VIS analysis for determination of Mw in papers with high lignin content had been verified before it was used as a comparative method for viscometry. Using SEC, changes in the weight average molecular mass (Mw) of cellulose tricarbanilate (CTC) derivative during delignification were evaluated. The results indicate that no significant depolymerization occurred in the selected samples under the studied delignification conditions, which was additionally confirmed with determination of monosaccharides by ion chromatography. The results of the Mw determinations by SEC and DPv by viscometry are in good correlation, justifying the use of viscometry after chlorite/acetic acid pretreatment to determine the cellulose average degree of polymerization in historical papers with high lignin content.
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Affiliation(s)
- Jasna Malešič
- Library Research Department, National and University Library, Turjaška 1, 1000 Ljubljana, Slovenia
- Correspondence:
| | - Ida Kraševec
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna Pot 113, 1001 Ljubljana, Slovenia; (I.K.); (I.K.C.)
| | - Irena Kralj Cigić
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna Pot 113, 1001 Ljubljana, Slovenia; (I.K.); (I.K.C.)
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Malešič J, Kolar J, Denac M, Kolar Bačnik B. Stabilisation Treatments for Paper with Green Copper Pigment Verdigris. RESTAURATOR-INTERNATIONAL JOURNAL FOR THE PRESERVATION OF LIBRARY AND ARCHIVAL MATERIAL 2020. [DOI: 10.1515/res-2020-0001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The focus of this research is the stabilisation of paper with Verdigris, a green copper pigment. Due to its corrosive effects on paper, many important documents, paintings and maps are in danger. The efficiency of several commercially available deacidification agents on paper samples with Verdigris was tested, including magnesium-based Bookkeeper® dispersion, nano calcium hydroxide containing Nanorestore® and CaLoSiL® dispersions as well as a recently developed dispersion of nano calcium carbonate. The antioxidant tetrabutylammonium bromide was tested either alone or in combination with nano calcium based deacidification agents. The effect of the treatments was evaluated using colour, tensile strength, degree of polymerization and pH measurements. The results indicate that acidic degradation does not play a major role during accelerated degradation of paper containing Verdigris with moderately acidic pH value and that oxidative decay could be the main culprit of the decay. The method described, which involves the use of antioxidant tetrabutylammonium bromide in combination with calcium carbonate based deacidification dispersion, was proved to have a superior effect against degradation of paper with Verdigris in comparison to the treatments which involve deacidification agents only. Nano calcium hydroxide based deacidification agents result in high pH values of the paper samples and therefore cannot be advised for use on paper documents.
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Affiliation(s)
- Jasna Malešič
- Research Department , National and University Library , Turjaška 1 , 1000 Ljubljana , Slovenia
| | - Jana Kolar
- CERIC-ERIC , S.S. 14 - km 163, 5 in, AREA Science Park , 34149 Basovizza , Trieste , Italy
| | - Mitja Denac
- Mala Slevica 2 , 1315 Velike Lašče , Slovenia
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3
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Influence of lignin content in cellulose pulp on paper durability. Sci Rep 2020; 10:19998. [PMID: 33203985 PMCID: PMC7673017 DOI: 10.1038/s41598-020-77101-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Accepted: 11/03/2020] [Indexed: 11/21/2022] Open
Abstract
Paper degradation on a macroscopic scale is characterised primarily by yellowing, an increase in brittleness, and other destructive changes caused by the hydrolysis of glycoside bonds and oxidation reactions. Until now, lignin has been believed to cause these changes. However, contemporary analysis has not confirmed this assumption and has attributed low paper resistance to ageing with acidification owing to the production in acid environments that involve aluminium sulfate. In view of the common belief this manuscript presents studies on the accelerated ageing of papers with different lignin contents that are produced in neutral environments. To achieve the objective, artificially aged papers under conditions of increased humidity and temperature were investigated using chromatographic (SEC) and spectroscopic (FTIR and UV–Vis spectroscopy) techniques. Mechanical tests were used to determine the decrease in tensile properties of the samples. We observed no effects of the lignin content on the ageing rate of paper produced at neutral pH. This work also reveals the extent to which spectroscopic methods are useful for studying the papers containing lignin.
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Amornkitbamrung L, Bračič D, Bračič M, Hribernik S, Malešič J, Hirn U, Vesel A, Kleinschek KS, Kargl R, Mohan T. Comparison of Trimethylsilyl Cellulose-Stabilized Carbonate and Hydroxide Nanoparticles for Deacidification and Strengthening of Cellulose-Based Cultural Heritage. ACS OMEGA 2020; 5:29243-29256. [PMID: 33225155 PMCID: PMC7676302 DOI: 10.1021/acsomega.0c03997] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 10/22/2020] [Indexed: 06/11/2023]
Abstract
Herein, colloidal dispersions of alkaline nanoparticles (NPs: CaCO3 and Mg(OH)2) are stabilized by trimethylsilyl cellulose (TMSC) in hexamethyldisiloxane and employed to treat historical wood pulp paper by an effortless dip-coating technique. Both alkaline NPs exhibit high stability and no size and shape changes upon stabilization with the polymer, as shown by UV-vis spectroscopy and transmission electron microscopy. The long-term effect of NP/TMSC coatings is investigated in detail using accelerated aging. The results from the pH-test and back-titration of coated papers show a complete acid neutralization (pH ∼ 7.4) and introduction of adequate alkaline reserve even after prolonged accelerated aging. Scanning electron microscopy-energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and infrared and water contact angle measurements showed the introduction of a thin and smooth hydrophobic NP/TMSC coating on the paper fibers. Acid-catalyzed desilylation of TMSC was observed by declining C-Si infrared absorbance peaks upon aging. The CaCO3 coatings are superior to Mg(OH)2 with respect to a reduced yellowing and lower cellulose degradation upon aging as shown by colorimetric measurements and degree of polymerization analysis. The tensile strength and folding endurance of coated and aged papers are improved to 200-300 and 50-70% as illustrated by tensile strength and double folding endurance measurements.
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Affiliation(s)
- Lunjakorn Amornkitbamrung
- Renewable
Energy Business Group, Mitr Phol Bio-Power
Co., Ltd., 2 Ploenchit
Center, Sukhumvit Road, Klongtoey, 10110 Bangkok, Thailand
| | - Doris Bračič
- Laboratory
for Characterization and Processing of Polymers, Faculty of Mechanical
Engineering, University of Maribor, Smetanova Ulica 17, 2000 Maribor, Slovenia
| | - Matej Bračič
- Laboratory
for Characterization and Processing of Polymers, Faculty of Mechanical
Engineering, University of Maribor, Smetanova Ulica 17, 2000 Maribor, Slovenia
| | - Silvo Hribernik
- Laboratory
for Characterization and Processing of Polymers, Faculty of Mechanical
Engineering, University of Maribor, Smetanova Ulica 17, 2000 Maribor, Slovenia
- Institute
of Automation, Faculty of Electrical Engineering and Computer Science, University of Maribor, Koroška cesta 46, 2000 Maribor, Slovenia
| | - Jasna Malešič
- National
and University Library, Turjaška 1, 1000 Ljubljana, Slovenia
| | - Ulrich Hirn
- Institute
of Bioproducts and Paper Technology, Graz
University of Technology, Inffeldgasse 23, 8010 Graz, Austria
| | - Alenka Vesel
- Department
of Surface Engineering and Optoelectronics, Jožef Stefan Institute, Teslova 30, SI-1000 Ljubljana, Slovenia
| | - Karin Stana Kleinschek
- Institute
for Chemistry and Technology of Biobased Systems (IBioSys), Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria
| | - Rupert Kargl
- Institute
for Chemistry and Technology of Biobased Systems (IBioSys), Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria
| | - Tamilselvan Mohan
- Laboratory
for Characterization and Processing of Polymers, Faculty of Mechanical
Engineering, University of Maribor, Smetanova Ulica 17, 2000 Maribor, Slovenia
- Institute
for Chemistry and Technology of Biobased Systems (IBioSys), Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria
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Bagniuk J, Pawcenis D, Conte AM, Pulci O, Aksamit-Koperska M, Missori M, Łojewska J. How to estimate cellulose condition in insulation transformers papers? Combined chromatographic and spectroscopic study. Polym Degrad Stab 2019. [DOI: 10.1016/j.polymdegradstab.2019.108951] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Degano I. Liquid chromatography: Current applications in Heritage Science and recent developments. PHYSICAL SCIENCES REVIEWS 2019. [DOI: 10.1515/psr-2018-0009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Liquid chromatography has been widely employed in the analysis of materials in Heritage Science, due to its ease of use and relatively low-cost, starting from thin layer chromatography of organic binders in paintings, of archaeological waxes and resins, and finally of natural dyes. High performance systems employing analytical columns containing packed stationary phases gradually supplanted thin layer chromatography (TLC) in the field, since the separation, detection and quantitation of specific species contained in a sample in the field of Cultural Heritage requires selective, sensitive and reliable methods, allowing for analysing a wide range of samples, in terms of analyte types and concentration range. Today, the main applications of High-Performance Liquid Chromatography in this field are related to the separation and detection of dyestuffs in archaeological materials and paint samples by reversed-phase liquid chromatography with suitable detectors. Proteomics and lipidomics are also gaining momentum in the last decade, thanks to the increased availability of instrumentation and procedures. In this chapter, principles and theory of liquid chromatography will be presented. A short review of the instrumentation needed to perform an analysis will be provided and some general principles of sample preparation revised. More details on the detection systems, the chromatographic set-ups and specific sample treatment strategies will be provided in the individual sections dedicated to the applications to Heritage Science of the main types of liquid chromatographic techniques. In particular, the applications of thin layer chromatography will be shortly described in paragraph 4.1. The applications of Reverse Phase High Performance Liquid Chromatography (RP-HPLC) will be discussed in detail in paragraph 4.2, including the analysis of natural and synthetic dyes and pigments and the profiling of lipid materials. The possibility to perform proteomic analysis will be presented and a link to the relevant Chapter in this book provided. The most important and promising applications of ion exchange chromatography (IC) will be discussed in paragraph 4.3. Finally, size exclusion and gel permeation chromatography (GPC) will be presented in paragraph 4.4, including applications to the study of polymeric network formation in paint binders, of the phenomena related to the depolymerisation of cellulose in paper and of cellulose and lignin in wood samples. The possibility to study synthetic polymers as artists’ materials and restorers’ tools by size exclusion (SEC) or gel permeation (GPC) will also be introduced. In the conclusions, future perspectives of liquid chromatography in Heritage Science will be briefly discussed.
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8
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Recognizing ancient papyri by a combination of spectroscopic, diffractional and chromatographic analytical tools. Sci Rep 2017; 7:46236. [PMID: 28382971 PMCID: PMC5382779 DOI: 10.1038/srep46236] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 03/14/2017] [Indexed: 12/04/2022] Open
Abstract
Ancient papyri are a written heritage of culture that flourished more than 3000 years ago in Egypt. One of the most significant collections in the world is housed in the Egyptian Museum and Papyrus Collection in Berlin, from where the samples for our investigation come. The papyrologists, curators and conservators of such collections search intensely for the analytical detail that would allow ancient papyri to be distinguished from modern fabrications, in order to detect possible forgeries, assess papyrus deterioration state, and improve the design of storage conditions and conservation methods. This has become the aim of our investigation. The samples were studied by a number of methods, including spectroscopic (FTIR, fluorescent-FS, Raman) diffractional (XRD) and chromatographic (size exclusion chromatography-SEC), selected in order to determine degradation parameters: overall oxidation of lignocellulosic material, degree of polymerization and crystallinity of cellulose. The results were correlated with those obtained from carefully selected model samples including modern papyri and paper of different composition aged at elevated temperature in humid air. The methods were classified in the order SEC > FS > FTIR > XRD, based on their effectiveness in discriminating the state of papyri degradation. However, the most trustworthy evaluation of the age of papyri samples should rely on several methods.
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Towards determination of absolute molar mass of cellulose polymer by size exclusion chromatography with mulitple angle laser light scattering detection. J Chromatogr A 2015. [PMID: 26210115 DOI: 10.1016/j.chroma.2015.06.042] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The study focuses on determination of a set of crucial parameters for molar mass calculation of cellulose from the results of size exclusion chromatography coupled with multiple angle laser light scattering (MALLS) and differential refractive index (DRI) detectors. In the present work, cellulose has been derivatised to obtain cellulose tricarbanilate (CTC) soluble in tetrahydrofuran (THF). The parameters of Rayleigh scattering in the MALLS detector: refractive index increment (dn/dc) and second virial coefficient (A2) of CTC in THF were determined for laser wavelength 658nm. In order to avoid errors resulting from cellulose derivatisation by-products present in the CTC solution, the so called "on-line" method of measuring dn/dc and A2 was applied. Based on the A2 determination, its influence on cellulose molar mass calculations and cellulose molecular dimensions were critically assessed. The latter includes evaluation of artificially aged cellulose towards conceivable branching by conformation plot analysis.
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Malešič J, Kolar J, Anders M. Evaluation of Treatments for Stabilization of Verdigris and Malachite Containing Paper Documents. RESTAURATOR-INTERNATIONAL JOURNAL FOR THE PRESERVATION OF LIBRARY AND ARCHIVAL MATERIAL 2015. [DOI: 10.1515/res-2015-0008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractCopper ions and acids lead to enhanced degradation of the paper carrier. Stabilization treatment of documents with pigments such as verdigris and malachite should therefore include addition of alkalis to combat acid hydrolysis of cellulose and antioxidants to retard oxidative degradation catalysed by copper ions. The paper reviews present approaches for stabilisation of green copper pigments. Furthermore, two recently proposed treatments containing tetraalkylammonium bromide antioxidants and alkali are evaluated. The first treatment is based on interleaving of paper samples containing malachite or verdigris pigments with papers, impregnated with alkaline buffer and antioxidant at elevated relative humidity and applied pressure. The second one is based on the use of non-aqueous suspensions of nano calcium carbonate and/or magnesium oxide particles and tetrabutylammonium or tetrapropylammonium bromide. Size exclusion chromatography is used to monitor the extent of degradation of samples during accelerated ageing, while colour changes of pigments are determined using colourimetry. Results demonstrate that effective stabilization of paper samples can be achieved with tetrabutylammonium bromide and calcium carbonate containing interleaves at 90% RH. When non-aqueous immersion treatment is applied, tetrabutylammonium bromide at a concentration 0.09 M in combination with calcium carbonate nano particles had the most beneficial effect on the paper as well as on the colour of the copper based pigments.
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Bronzato M, Calvini P, Federici C, Bogialli S, Favaro G, Meneghetti M, Mba M, Brustolon M, Zoleo A. Degradation Products from Naturally Aged Paper Leaves of a 16th-Century-Printed Book: A Spectrochemical Study. Chemistry 2013; 19:9569-77. [DOI: 10.1002/chem.201300756] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Indexed: 11/12/2022]
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Kolar J, Malešič J, Kočar D, Strlič M, De Bruin G, Koleša D. Characterisation of paper containing iron gall ink using size exclusion chromatography. Polym Degrad Stab 2012. [DOI: 10.1016/j.polymdegradstab.2012.08.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Łojewski T, Zieba K, Lojewska J. Size exclusion chromatography and viscometry in paper degradation studies. New Mark-Houwink coefficients for cellulose in cupri-ethylenediamine. J Chromatogr A 2010; 1217:6462-8. [PMID: 20833398 DOI: 10.1016/j.chroma.2010.07.071] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2009] [Revised: 07/21/2010] [Accepted: 07/27/2010] [Indexed: 10/19/2022]
Abstract
The paper deals with the application of size exclusion chromatography (SEC) for the studies of paper degradation phenomena. The goal is to solve some of the technical problems connected with the calibration of multi-detector SEC system and to find the correlation between SEC and viscometric results of degree of polymerization of cellulose. The results gathered for the paper samples degraded by acidic air pollutant (NO(2)) are used as an example of SEC-MALLS application. From the correlation between intrinsic viscosities and absolute value of molecular masses obtained with SEC/MALLS (Multi Angle Laser Light Scattering) technique, Mark-Houwink coefficients for cellulose in cupri-ethylenediamine solution were determined. Thus obtained coefficients were used for the determination of viscometric degree of polymerization (molecular mass) of the aged samples. An excellent correlation was found between the chromatographic values of molecular masses obtained with SEC-UV/VIS detection and the viscometric ones utilizing the improved values of Mark-Houwink coefficients.
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Affiliation(s)
- Tomasz Łojewski
- Department of Chemistry, Jagiellonian University, 30-060 Kraków, Ingardena 3, Poland.
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Strlič M, Cséfalvayová L, Kolar J, Menart E, Kosek J, Barry C, Higgitt C, Cassar M. Non-destructive characterisation of iron gall ink drawings: Not such a galling problem. Talanta 2010; 81:412-7. [DOI: 10.1016/j.talanta.2009.12.017] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2009] [Accepted: 12/13/2009] [Indexed: 11/25/2022]
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Stephens CH, Shrestha B, Morris HR, Bier ME, Whitmore PM, Vertes A. Minimally invasive monitoring of cellulose degradation by desorption electrospray ionization and laser ablation electrospray ionization mass spectrometry. Analyst 2010; 135:2434-44. [DOI: 10.1039/c0an00155d] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Lin JH, Chang YH, Hsu YH. Degradation of cotton cellulose treated with hydrochloric acid either in water or in ethanol. Food Hydrocoll 2009. [DOI: 10.1016/j.foodhyd.2008.10.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Popovici ST, Schoenmakers PJ. Fast size-exclusion chromatography--theoretical and practical considerations. J Chromatogr A 2005; 1099:92-102. [PMID: 16330275 DOI: 10.1016/j.chroma.2005.08.071] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2004] [Revised: 08/22/2005] [Accepted: 08/24/2005] [Indexed: 11/15/2022]
Abstract
Fast SEC is a very interesting modification of conventional SEC. The need for it emerges from combinatorial chemistry and high-throughput experimentation, where high-speed analyses are required. The different approaches to change the speed of analysis are extensively described in this paper. Special attention is paid to the trade-off between analysis time and resolution and to the selection of optimal column lengths and flow rates. Simulations are used to design and to understand experiments. Integrity plots are constructed to judge the quality of various SEC systems. Fast separations in size-exclusion chromatography are found to be more favorable than suggested by conventional theory. The results are based on experimental data obtained for polystyrene using THF as mobile phase.
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Affiliation(s)
- Simona T Popovici
- van't Hoff Institute for Molecular Sciencies (HIMS), University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands
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Lacharme F, Lapeyre V, Ravaine V. Full verification of the liquid exclusion-adsorption chromatography theory using monolithic capillary columns. J Chromatogr A 2005; 1074:89-98. [PMID: 15941043 DOI: 10.1016/j.chroma.2005.03.112] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Capillary electrochromatography (CEC) was used to separate alkyl phenol ethoxylates (APEs) as model diblock copolymers, with monolithic polymers as stationary phases. The order of elution indicate that the two polymer blocks follow distinct chromatographic modes: size-exclusion for the poly(oxyethylene) group and adsorption interaction for the alkyl part. Therefore, our experimental results were compared to the theory describing liquid exclusion-adsorption chromatography (LEAC). They were found in perfect agreement with the theory, which turned to be verified for the first time over the full range of polymer lengths.
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Affiliation(s)
- Frédéric Lacharme
- Laboratoire d'Analyse Chimique par Reconnaissance Moléculaire (LACReM), ENSCPB, 16 Av Pey Berland, 33607 Pessac, France
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Oudhoff KA, Macka M, Haddad PR, Schoenmakers PJ, Kok WT. Contactless conductivity detection of synthetic polymers in non-aqueous size-exclusion electrokinetic chromatography. J Chromatogr A 2005; 1068:183-7. [PMID: 15844557 DOI: 10.1016/j.chroma.2004.11.081] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A capacitively coupled contactless conductivity detection (CCD) system has been applied for the detection of neutral synthetic polymers in capillary size-exclusion electrokinetic chromatography (SEEC). Polystyrene standards, that were used as a model compounds, were separated on a capillary column packed with porous 10 microm silica particles with an electrokinetically driven mobile phase, and detected by CCD and UV detection simultaneously. Mass-calibration curves for polystyrene were constructed. Satisfactory results were obtained for the linearity, the run-to-run repeatability (<0.2% for the relative retention and <4% for the peak area) and the robustness of the detector. One of the major issues in this preliminary study was to investigate the origin of the peaks observed for the polystyrene standards. The effect of the molar mass of the polystyrenes on the sensitivity was small. Therefore, the signals obtained could not be explained as the result of an increased viscosity and a decreased solution conductivity of the solute zone. An alternative hypothesis is suggested, and recommendations for further research are given.
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Affiliation(s)
- Kathalijne A Oudhoff
- Polymer-Analysis Group, Van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands
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Abstract
In this review the literature on the application of capillary electrochromatography (CEC) for size-based separations of macromolecules is summarized. Opportunities and limitations of CEC specially related to the size-exclusion mode (SEEC) are indicated. Applications with synthetic polymer samples as well as with biomacromolecules (polysaccharides, proteins) are shown. The prospects for a further development and application of SEEC are discussed.
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Affiliation(s)
- Wim Th Kok
- Polymer-Analysis Group, Department of Chemical Engineering, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands.
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Evaluating the Effects of Treatments on Iron Gall Ink Corroded Documents. A new analytical methodology. RESTAURATOR-INTERNATIONAL JOURNAL FOR THE PRESERVATION OF LIBRARY AND ARCHIVAL MATERIAL 2004. [DOI: 10.1515/rest.2004.94] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Strlic M, Kolar J. Size exclusion chromatography of cellulose in LiCl/N,N-dimethylacetamide. JOURNAL OF BIOCHEMICAL AND BIOPHYSICAL METHODS 2003; 56:265-79. [PMID: 12834982 DOI: 10.1016/s0165-022x(03)00064-2] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Size exclusion of cellulose in LiCl/N,N-dimethylacetamide has been used for the past 15 years, yet much of the current research is still devoted to fundamental studies, as many issues regarding column calibration, separation mechanisms and solution behavior have not been resolved yet. The paper reviews practical aspects of sample preparation and it is demonstrated that sample heating and several techniques to aid solvent exchange call for reevaluation. It is further shown that the use of internal standard may introduce minor improvements in repeatability. The commonly used column calibration procedures, chromatographic conditions and applications are also reviewed. Further research is needed to understand the mechanisms of separation, to optimize column calibration and to facilitate and optimize sample preparation.
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Affiliation(s)
- Matija Strlic
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Askerceva 5, Ljubljana SI-1000, Slovenia.
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