Analysis of the stable free radical scavenging capability of artificial polyphenol mixtures and plant extracts by capillary electrophoresis and liquid chromatography-diode array detection-tandem mass spectrometryHelmja, Kati; Vaher, Merike; Püssa, Tõnu; Kaljurand, MihkelJournal of chromatography A2009 / p. 2417-2423 : ill

Bioactive components of the hop strobilus : comparison of different extraction methods by capillary electrophoretic and chromatographic methodsHelmja, Kati; Vaher, Merike; Püssa, Tõnu; Kamsol, Kristjan; Orav, Anne; Kaljurand, MihkelJournal of chromatography A2007 / p. 222-229 : ill https://www.academia.edu/60646251/Bioactive_components_of_the_hop_strobilus_Comparison_of_different_extraction_methods_by_capillary_electrophoretic_and_chromatographic_methods

Bioaktiivsete ühendite lahutamine ja antioksüdatiivsuse hindamine maavitsaliste perekonda Solanaceae kuuluvatel taimedelHelmja, Kati; Vaher, Merike; Püssa, Tõnu; Kaljurand, MihkelXXX Eesti keemiapäevad : teaduskonverentsi teesid = 30th Estonian Chemistry Days : abstracts of scientific conference2007 / lk. 36-37

Bioprotsesside kapillaarelektroforeetiline jälgimineHelmja, Kati; Tahkoniemi, Heli; Kaljurand, MihkelXXIX Eesti keemiapäevad : teaduskonverentsi ettekannete teesid = 29th Estonian Chemistry Days : abstracts of scientific conference2005 / lk. 15-16

Capillary electrophoretic monitoring of hydrothermal pre-treatment and enzymatic hydrolysis of willow : comparison with HPLC and NMRVaher, Merike; Helmja, Kati; Käsper, Andres; Kurašin, Mihhail; Väljamäe, Priit; Kudrjašova, Marina; Koel, Mihkel; Kaljurand, MihkelCatalysis today2012 / p. 34-41 : ill

Capillary electrophoretic monitoring of microbial growth : determination of organic acidsKudrjašova, Marina; Tahkoniemi, Heli; Helmja, Kati; Kaljurand, MihkelProceedings of the Estonian Academy of Sciences. Chemistry2004 / 2, p. 51-64 : ill

Capillary electrophoretic monitoring of products of enzymatic digestion of willow sawdustHelmja, Kati; Käsper, Andres; Kudrjašova, Marina; Vaher, MerikeSustainChem2011 : International Conference on Materials and Technologies for Green Chemistry jointly with Workshop of COST Action CM0903 (UBIOCHEM-II) : September 5-9, 2011, Tallinn, Estonia : abstract book and program2011 / p. 105 https://www.etis.ee/Portal/Publications/Display/b8a916a7-4a4b-460f-a3de-eede27394252

Characterization of bioactive compounds contained in vegetables of the Solnaceae family by capillary electrophoresisHelmja, Kati; Vaher, Merike; Gorbatšova, Jelena; Kaljurand, MihkelProceedings of the Estonian Academy of Sciences. Chemistry2007 / 4, p. 172-186 : ill

Chemical composition of red wines made from hybrid grape and common grape (Vitis vinifera L.) cultivarsPedastsaar, Priit; Vaher, Merike; Helmja, Kati; Kulp, Maria; Kaljurand, Mihkel; Karp, Kadri; Raal, Ain; Karathanos, Vaios; Püssa, TõnuProceedings of the Estonian Academy of Sciences2014 / p. 444-453 : ill https://artiklid.elnet.ee/record=b2707387*est

Comparative study of antioxidant capacity of Rheum rhaponticum root polyphenolsRaudsepp, Piret; Helmja, Kati; Raal, Ain; Vaher, Merike; Püssa, TõnuXXIVth International Conference on Polyphenols : Polyphenols Communications 2008 : Salamanca, 8th-11th July 2008. Volume 12008 / p. 231-232 : ill

Comparison of the composition of phenolic acids and antioxidativity of different wheat varietiesMatso, Kersti; Levandi, Tuuli; Helmja, Kati; Vaher, MerikeNoSSS2009 : 5th Conference on Separation and Related Techniques by Nordic Separation Science Society : 26-29 August, 2009, Tallinn University of Technology, Estonia : abstract book and program2009 / p. 116

Complex study of bioactive compounds in egglant (Solanum melongena)Helmja, Kati; Gorbatšova, Jelena; Vaher, Merike; Püssa, Tõnu; Kaljurand, Mihkel4th Nordic Separation Science Society (NoSSS) International Conference : Kaunas, August 26-29, 2007 : abstracts book2007 / p. 77

Comprehensive investigation of St.John's Worth (Hypernicum perforatum) : polyphenolic compounds, essential oils and metalsHelmja, Kati; Vaher, Merike; Orav, Anne; Viitak, Anu; Püssa, Tõnu; Kaljurand, Mihkel14th International Symposium on Separation Science : Primosten, Croatia, 30 Sept. - 3 Oct. 20082008 / p. 59

Determination of carbohydrates in cellulose and enzymatically pretreated wood fractions using capillary electrophoresisVaher, Merike; Helmja, Kati; Käsper, Andres; Kudrjašova, Marina; Gorbatšova, Jelena; Kaljurand, MihkelProgram and abstract book : Nordic Separation Science Society 6th Conference : Riga, Latvia, August 24th-27th, 20112011 / p. 98

Determination of phenolic compounds and their antioxidative capability in plant extracts = Meetodid fenoolsete ühendite määramiseks ja nende antioksüdatiivsuse hindamiseksHelmja, Kati2010 https://www.ester.ee/record=b2561129*est

Determination of varietal thiols in white wines using LC-MS/MS-SIDAHelmja, Kati; Nisamedtinov, Ildar; Kirsipuu, Tiina14th Baltic Conference on Food Science and Technology "Sustainable Food for Conscious Consumer" : FoodBalt 2021 : book of abstracts2021 / p. 23

Enantioselective CE analysis of hepatic ketamine metabolism in different species in vitroSchmitz, Andrea; Thormann, Wolfgang; Moessner, Lone; Theurillat, Regula; Helmja, Kati; Mevissen, MeikeElectrophoresis2010 / 9, p. 1506-1516 : ill

Evaluation of antioxidative capability of the tomato (Solanum lycopersicum) skin constituents by capillary electrophoresis and high-performanced liquid chromatographyHelmja, Kati; Vaher, Merike; Püssa, Tõnu; Raudsepp, Piret; Kaljurand, MihkelElectrophoresis2008 / p. 3980-3988 : ill

Evaluation of the free radical scavenging capability of wheat extracts by capillary electrophoresis and multivariate curve resolutionHelmja, Kati; Vaher, Merike; Kaljurand, MihkelElectrophoresis2011 / 9, p. 1094-1100 : ill

Fenoolsete ühendite sisaldus ja antioksüdatiivsus erinevates nisusortides ja nisutera fraktsioonidesMatso, Kersti; Vaher, Merike; Helmja, Kati; Levandi, Tuuli; Kaljurand, MihkelXXXI Eesti keemiapäevad : [28. aprill 2010, Tallinn] : teaduskonverentsi teesid = 31st Estonian Chemistry Days : abstracts of scientific conference2010 / lk. 56

Fermentation reactor coupled with capillary electrophoresis for on-line bioprocess monitoringTahkoniemi, Heli Anneli; Helmja, Kati; Menert, Anne; Kaljurand, MihkelJournal of pharmaceutical and biomedical analysis2006 / 5, p. 1585-1591 : ill

Fraction collection in capillary electrophoresis for various stand-alone mass spectrometersHelmja, Kati; Borissova, Maria; Knjazeva, Tatjana; Jaanus, Martin; Muinasmaa, Urmas; Kaljurand, Mihkel; Vaher, MerikeJournal of chromatography A2009 / p. 3666-3673 : ill

Identification of bioactive compounds in leaves and stems of Aegopodium podagraria by various analytical technicsOrav, Anne; Viitak, Anu; Helmja, Kati; Vaher, MerikeNoSSS2009 : 5th Conference on Separation and Related Techniques by Nordic Separation Science Society : 26-29 August, 2009, Tallinn University of Technology, Estonia : abstract book and program2009 / p. 144

Methods of comparative analysis of the free radical scavenging capability of components of antioxidant mixturesPüssa, Tõnu; Vaher, Merike; Helmja, Kati; Raudsepp, Piret; Kaljurand, MihkelNoSSS2009 : 5th Conference on Separation and Related Techniques by Nordic Separation Science Society : 26-29 August, 2009, Tallinn University of Technology, Estonia : abstract book and program2009 / p. 56

Mine praktikale! IASTE-ga : [ka Maarja Ehala, Kati Helmja ja Kätrin Karu muljeid praktikast]Valgeväli, Kadri-Ann; Ehala, Maarja; Helmja, Kati; Karu, KätrinStudioosus2004 / Veebr., lk. 8-9

Phenolic compounds and the antioxidant activity of the bran, flour and whole grain of different wheat varietiesVaher, Merike; Matso, Kersti; Levandi, Tuuli; Helmja, Kati; Kaljurand, MihkelProcedia chemistry2010 / p. 76-82 : ill https://www.sciencedirect.com/science/article/pii/S1876619609004094

Polüfenoolsete ühendite antioksüdatiivsuse hindamine kapillaarelektroforeetiliselt ja vedelik-kromatograafiliseltHelmja, Kati; Vaher, Merike; Püssa, Tõnu; Kaljurand, MihkelXXXI Eesti keemiapäevad : [28. aprill 2010, Tallinn] : teaduskonverentsi teesid = 31st Estonian Chemistry Days : abstracts of scientific conference2010 / lk. 31

Portatiivne kapillaarelektroforeesi aparaat keskkonnareostuse analüüsiksKnjazeva, Tatjana; Makarõtševa, Natalja; Kobrin, Eeva-Gerda; Helmja, Kati; Seiman, Andrus; Vaher, Merike; Kaljurand, MihkelXXXI Eesti keemiapäevad : [28. aprill 2010, Tallinn] : teaduskonverentsi teesid = 31st Estonian Chemistry Days : abstracts of scientific conference2010 / lk. 46

Study of VFAs formation during anaerobic digestion of thermally treated sludge by respirometric Oxitop methodMenert, Anne; Michelis, Merje; Helmja, Kati; Tahkoniemi, Heli Anneli; Vaalu, Tarmo; Malsub, Tõnu; Vilu, Raivo; Kaljurand, MihkelProceedings of 5th Conference on the Establishment of Cooperation between Companies and Institutions in the Baltic Sea Region2005 / p. 563

The evaluation of the oxidation capability of bioactive compounds of Solanum melongena by capillary electrophoresis and by HPLC-MS/MSHelmja, Kati; Vaher, Merike; Püssa, Tõnu; Kaljurand, MihkelXXIVth International Conference on Polyphenols : Polyphenols Communications 2008 : Salamanca, 8th-11th July 2008. Volume 12008 / p. 165-166 : ill

Tselluloosi hüdrolüüs ioonses vedelikusHelmja, Kati; Vaher, MerikeXXXII Eesti Keemiapäevad : teaduskonverentsi teesid2011 / lk. 25

Variation in the composition of the essential oils, phenolic compounds and mineral elements of Hypericum perforatum L. growing in EstoniaHelmja, Kati; Vaher, Merike; Püssa, Tõnu; Orav, Anne; Viitak, Anu; Levandi, Tuuli; Kaljurand, MihkelNatural product research2011 / p. 496-510