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Patrick G. Hatcher - One of the best experts on this subject based on the ideXlab platform.
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characterization of organic matter from natural waters using Tetramethylammonium Hydroxide thermochemolysis gc ms
Journal of Analytical and Applied Pyrolysis, 2003Co-Authors: Scott W Frazier, Kirk O Nowack, Kenya M Goins, Fred S Cannon, Louis A Kaplan, Patrick G. HatcherAbstract:Abstract The Tetramethylammonium Hydroxide (TMAH) thermochemolysis method was recently introduced for the qualitative characterization of organic matter from natural waters (NOM). Such characterizations were usually of a qualitative nature, and any semiquantitative assessments of individual compounds were often achieved by measuring relative areas and assuming unity as a response factor. In this paper we evaluate the quantitative measurement of many identified products characteristic of lignin and NOM using an internal standard approach. The relative standard deviation for most quantified compounds was between 1 and 10%. Four NOM samples, isolated by low-temperature, low-pressure evaporation and freeze-drying, were collected from temperate as well as tropical climates. Large variations were found between samples with respect to the distribution of compounds such as fatty acids, lignin-derived compounds, carbohydrate-derived compounds, and protein-derived compounds. We quantified most lignin-derived and aromatic TMAH products as well as fatty acids (as their methyl esters, FAME) that were found in this set of NOM samples. The contribution of lignin-derived compounds to the total quantified TMAH product distribution in these four samples varied between 21 and 35%. The contribution of FAMEs ranged from 32 to 51% whereas the contribution from non-lignin aromatic compounds was 24–32%. TMAH thermochemolysis potentially provides significant information about NOM sources, compared with other degradative techniques, since both lignin-derived compounds and lipids can be quantitatively and simultaneously investigated.
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Characterization of amino acids and proteinaceous materials using online Tetramethylammonium Hydroxide (TMAH) thermochemolysis and gas chromatography-mass spectrometry technique
Journal of Analytical and Applied Pyrolysis, 2001Co-Authors: Xu Zang, Johnie C Brown, Jasper D.h Van Heemst, Amanda Palumbo, Patrick G. HatcherAbstract:Abstract An on-line thermochemolysis technique using Tetramethylammonium Hydroxide (TMAH) for the characterization of amino acids and proteinaceous materials was developed. Amino acids were converted to their corresponding N -and O -methyl derivatives by TMAH in the pyrolysis chamber for 15 s at 300°C prior to separation and detection by gas chromatography-mass spectrometry. Thermochemolysis reactions of TMAH with protein and macromolecular environmental sample were also performed. Results show that the peptide bonds were effectively cleaved by thermochemolysis reaction, yielding individual amino acid methyl esters. Thus, this on-line TMAH thermochemolysis technique is an easy and efficient method for the characterization of amino acids and proteinaceous materials.
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characterization of organic matter in soils by thermochemolysis using Tetramethylammonium Hydroxide tmah
Soil Science Society of America Journal, 2000Co-Authors: Benny Chefetz, Yona Chen, Edward C Clapp, Patrick G. HatcherAbstract:Tetramethylammonium Hydroxide (TMAH) thermochemolysis-gas chromatography/mass spectrometry (GC/MS) was employed to study the chemical structure of soil organic matter sampled from a soil plot in which corn (Zea mays L.) was farmed continuously for 15 yr. The chromatograms exhibited peaks related to compounds derived from lignin, fatty acid methyl esters (FAMEs), non-lignin aromatic structures, and heterocyclic N compounds. The dominant lignin-derived peaks in the TMAH thermochemolysis-GC/MS chromatograms were mainly derivatives of p-hydroxyphenyl and guaiacyl structures, suggesting a non-woody (grass) lignin type. With depth, the ratio of syringyl to guaiacyl compounds (S/G) decreased, suggesting a preferential degradation of the syringyl units by microorganisms. Fatty acid methyl esters of varying (-'-chain length (C 7 to C 27 ) were identified in the soil chromatograms. Both TMAH-GC/MS and 13 C-NMR (nuclear magnetic resonance) data suggested a relative increase of long chain fatty acids with soil depth (or degree of humification), suggesting a refractory nature for these compounds. The heterocyclic N compounds yielded from the TMAH thermochemolysis were mainly pyrroles pyridines, and pyrazoles. In addition, low levels of methylated amino acids (phenylalanine, leucine, and valine) were detected. The presence of the amino acids in the bottom layer of the soil suggests a preservation mechanism. The changes identified in the chemical components provide clues as to the nature of the humification processes in the soil profile and also yield information on the nature of the sources of soil organic matter.
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analysis of aliphatic biopolymers using thermochemolysis with Tetramethylammonium Hydroxide tmah and gas chromatography mass spectrometry
Organic Geochemistry, 1998Co-Authors: Jose C Del Rio, Patrick G. HatcherAbstract:Abstract Selected aliphatic biopolyesters (cutins, cuticles and a suberin) isolated from different plants have been analyzed using thermochemolysis with Tetramethylammonium Hydroxide (TMAH). This method consists of a high-temperature saponification/transesterification, and yields methyl esters of fatty acids and the methyl ethers of alcohols, which are subsequently analyzed by gas chromatography and gas chromatography–mass spectrometry. The main compounds produced from the analyzed samples correspond to the methyl derivatives of long-chain fatty acids, hydroxy fatty acids and α,ω-alkanedioic acids. The composition of the released compounds are similar to those reported in the literature using different depolymerization methods. The main advantage of the procedure is that it is easily performed in glass tubes with very low amounts of sample and without additional derivatization steps prior to gas chromatographic analysis because the products are methylated in situ. The method also avoids the laborious and time consuming sample preparation of extractive methods and the use of large amounts of solvents.
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Structural characterization of bio- and geo-macromolecules by off-line thermochemolysis with Tetramethylammonium Hydroxide
Journal of Chromatography A, 1998Co-Authors: J.c. Del Río, Daniel E. Mckinney, Heike Knicker, Mark A. Nanny, Robert D. Minard, Patrick G. HatcherAbstract:A new analytical procedure, Tetramethylammonium Hydroxide thermochemolysis, was used to structurally characterize a variety of bio-and geo-polymers. The technique cleaves esters and some ethers in macromolecular organic matter, yielding low-molecular-mass monomers such as methyl esters of carboxylic acids and methyl ethers of alcohols that are amenable to gas chromatographic analysis. This procedure can be conducted in sealed glass ampoules, which means that it can be easily implemented in any laboratory having gas chromatographic capabilities, in contrast to other chemolytic or pyrolytic procedures. A set of biogeomacromolecules, ranging from gymnosperm and angiosperm woods, natural polyesters such as cutin, dissolved organic matter in natural and oceanic waters, and humic substances were characterized with this procedure. The information obtained provides molecular-level details which can be used to infer structural composition.
Kenichi Kuroda - One of the best experts on this subject based on the ideXlab platform.
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Tetramethylammonium Hydroxide (TMAH) thermochemolysis of 2-arylcoumaran lignin model compounds
Journal of Analytical and Applied Pyrolysis, 2009Co-Authors: Kenichi Kuroda, Akiko Nakagawa-izumi, Tatsuya Ashitani, Koki FujitaAbstract:Abstract Phenolic 2-arylcoumarans 1 – 6 were used to examine the behaviors of β-5 subunits in lignin during Tetramethylammonium Hydroxide (TMAH) thermochemolysis. Products were monitored by gas chromatography/mass spectrometry. The process predominantly provided dimeric products with the opened hydrofuran ring. Substituent changes at the γ-position of ring A and at the 5-position of ring B had a large effect on the product compositions. 2-Arylcoumarans 1 and 6 with the γ-CH 2 OH substituent predominantly gave 2,3,3′,4′-tetramethoxystilbenes involving the elimination of the γ-CH 2 OH substituent, while 2 – 5 with the γ-CH 3 substituent gave a mixture of 2,3,3′,4′-tetramethoxy-α-methylstilbenes and α-methoxy-α-(3′,4′-dimethoxyphenyl)-β-(2,3-dimethoxyphenyl)propanes. Substituent –CH CHCH 3 on ring B remained unaffected. Substituents –CH CHCH 2 OH and –COOH on ring B produced the corresponding methyl ether and ester, respectively, by methylation. The –CH CHCHO substituent on ring B was converted to the –CHO substituent.
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Tetramethylammonium Hydroxide (TMAH) thermochemolysis of lignin: behavior of 4-O-etherified cinnamyl alcohols and aldehydes.
Journal of agricultural and food chemistry, 2005Co-Authors: Kenichi Kuroda, Akiko Nakagawa-izumiAbstract:The thermochemolytic behavior of 4-O-etherified cinnamyl alcohols and aldehydes in lignin was investigated in the presence of Tetramethylammonium Hydroxide (TMAH) (315 degrees C/4 s), using veratrylglycol-beta-(coniferyl alcohol) ether (1a), veratrylglycol-beta-(sinapyl alcohol) ether (1b), and veratrylglycol-beta-(coniferyl aldehyde) ether (2). The methylated products were monitored with gas chromatography-mass spectrometry. Dimers 1a and 1b provided the coniferyl and sinapyl alcohol dimethyl ethers consisting of three isomers, respectively. Coniferyl alcohol dimethyl ether isomers were also observed in the TMAH thermochemolysis pyrolysates of a bulk dehydrogenation polymer of coniferyl alcohol and a Japanese cedar (Cryptomeria japonica) wood. Coniferyl aldehyde methyl ether was not provided from TMAH thermochemolyses of coniferyl aldehyde, 2, a dehydrogenation polymer of coniferyl aldehyde, and the cedar wood. The former three provided veratryl aldehyde in a large abundance, instead of coniferyl aldehyde methyl ether. Sinapyl aldehyde provided 3,4,5-trimethoxybenzaldehyde in a large abundance and sinapyl aldehyde methyl ether in a trace abundance. The results showed that TMAH thermochemolysis is an effective tool to obtain information on cinnamyl alcohol end groups, but is not applicable to analysis of cinnamyl aldehyde end groups.
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Tetramethylammonium Hydroxide thermochemolysis of guaiacyl syringyl and guaiacyl dehydrogenation polymers
Organic Geochemistry, 2005Co-Authors: Kenichi Kuroda, Akiko NakagawaizumiAbstract:Abstract Tetramethylammonium Hydroxide thermochemolysis of lignin was investigated using guaiacyl–syringyl and guaiacyl dehydrogenation polymers. The guaiacyl–syringyl mixed polymer provided: (1) 1-(3,4-dimethoxyphenyl)-1,2,3-trimethoxypropane isomers ( 11 / 12 ) and 1-(3,4,5-trimethoxyphenyl)-1,2,3-trimethoxypropane isomers ( 15 / 16 ) as β-aryl ether subunit-derived products, (2) 2,3,3′,4′-tetramethoxy-5-(3-methoxyprop-1-enyl)stilbene ( 18 ) and 2,3,3′,4′,5′-pentamethoxy-5-(3-methoxyprop-1-enyl)stilbene ( 22 ) as β-5 subunit-derived products, (3) pinoresinol dimethyl ether ( 21 ), medioresinol dimethyl ether ( 23 ) and syringaresinol dimethyl ether ( 24 ) as β–β subunit-derived products, respectively, and (4) coniferyl alcohol dimethyl ether ( 8 ) and sinapyl alcohol dimethyl ether ( 14 ) from 4- O -linked coniferyl and sinapyl alcohols. The ratio of products stemming from β-aryl ether, β-5, β–β subunits was 23:13:64. The guaiacyl polymer provided 11 / 12 , 18 , 21 , and 8 , suggesting the same reactions occurring also in the guaiacyl polymer, although the ratio (31:32:37) of the products from β-aryl ether, β-5, β–β subunits differed.
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Tetramethylammonium Hydroxide thermochemolysis of guaiacyl–syringyl and guaiacyl dehydrogenation polymers
Organic Geochemistry, 2005Co-Authors: Kenichi Kuroda, Akiko Nakagawa-izumiAbstract:Abstract Tetramethylammonium Hydroxide thermochemolysis of lignin was investigated using guaiacyl–syringyl and guaiacyl dehydrogenation polymers. The guaiacyl–syringyl mixed polymer provided: (1) 1-(3,4-dimethoxyphenyl)-1,2,3-trimethoxypropane isomers ( 11 / 12 ) and 1-(3,4,5-trimethoxyphenyl)-1,2,3-trimethoxypropane isomers ( 15 / 16 ) as β-aryl ether subunit-derived products, (2) 2,3,3′,4′-tetramethoxy-5-(3-methoxyprop-1-enyl)stilbene ( 18 ) and 2,3,3′,4′,5′-pentamethoxy-5-(3-methoxyprop-1-enyl)stilbene ( 22 ) as β-5 subunit-derived products, (3) pinoresinol dimethyl ether ( 21 ), medioresinol dimethyl ether ( 23 ) and syringaresinol dimethyl ether ( 24 ) as β–β subunit-derived products, respectively, and (4) coniferyl alcohol dimethyl ether ( 8 ) and sinapyl alcohol dimethyl ether ( 14 ) from 4- O -linked coniferyl and sinapyl alcohols. The ratio of products stemming from β-aryl ether, β-5, β–β subunits was 23:13:64. The guaiacyl polymer provided 11 / 12 , 18 , 21 , and 8 , suggesting the same reactions occurring also in the guaiacyl polymer, although the ratio (31:32:37) of the products from β-aryl ether, β-5, β–β subunits differed.
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thermochemolytic behavior of β β lignin structures in the presence of Tetramethylammonium Hydroxide tmah
Organic Geochemistry, 2004Co-Authors: Akiko Nakagawaizumi, Kenichi Kuroda, Tetsuo OzawaAbstract:Abstract Tetramethylammonium Hydroxide (TMAH) thermochemolysis is widely used as an effective tool for characterizing hydrolyzable biopolymers such as lignin because it provides more products reflecting structural attributes of the polymer than conventional pyrolysis. However, its functions and the origins of the products are still unclear. Lignin model compounds containing a β–β linkage were subjected to TMAH thermochemolysis (500 °C/4 s) to investigate product distributions and reaction mechanisms. The methylated products were analyzed by gas chromatography/mass spectrometry (GC/MS). Pinoresinols (2,3) and syringaresinol (5) provided di-O-methylpinoresinol (4) and di-O-methylsyringaresinol (6), respectively, as the major product, and methylated monomers. The contribution of di-O-methylresinols was ca 80% in the pyrolyzates based on GC/MS signal areas. A guaiacyl synthetic lignin and a Japanese cedar (Cryptomeria japonica) wood lignin also yielded 4 in large and small abundances, respectively, due to the abundances of β–β subunits in the lignins and the interconnection modes of the β–β subunits with other subunits. The results demonstrated that the TMAH thermochemolysis method is a good tool for analyzing β–β subunits in lignins.
Ralph E Sturgeon - One of the best experts on this subject based on the ideXlab platform.
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determination of inorganic mercury in biological tissues by cold vapor atomic absorption spectrometry following Tetramethylammonium Hydroxide solubilization
Journal of Analytical Atomic Spectrometry, 1999Co-Authors: Guanhong Tao, S N Willie, Ralph E SturgeonAbstract:A rapid and simple method for the quantification of inorganic and total mercury in biological tissues using flow injection cold vapor generation atomic absorption spectrometry is presented. Samples were solubilized using Tetramethylammonium Hydroxide. The inorganic Hg was released by on-line addition of L-cysteine and then reduced to metallic Hg by SnCl2. The detection limit for inorganic mercury was 0.1 µg l–1 and the precision of determination was better than 2% (RSD) at 20 µg l–1. The proposed method was validated by the analyses of a suite of certified marine biological reference materials, DORM-2 (dogfish muscle), DOLT-2 (dogfish liver) and TORT-2 (lobster hepatopancreas).
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Determination of inorganic mercury in biological tissues by cold vapor atomic absorption spectrometry following Tetramethylammonium Hydroxide solubilization
Journal of Analytical Atomic Spectrometry, 1999Co-Authors: Guanhong Tao, S N Willie, Ralph E SturgeonAbstract:A rapid and simple method for the quantification of inorganic and total mercury in biological tissues using flow injection cold vapor generation atomic absorption spectrometry is presented. Samples were solubilized using Tetramethylammonium Hydroxide. The inorganic Hg was released by on-line addition of L-cysteine and then reduced to metallic Hg by SnCl2. The detection limit for inorganic mercury was 0.1 \ub5g l\u20131 and the precision of determination was better than 2% (RSD) at 20 \ub5g l\u20131. The proposed method was validated by the analyses of a suite of certified marine biological reference materials, DORM-2 (dogfish muscle), DOLT-2 (dogfish liver) and TORT-2 (lobster hepatopancreas).Peer reviewed: NoNRC publication: Ye
Akiko Nakagawa-izumi - One of the best experts on this subject based on the ideXlab platform.
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Tetramethylammonium Hydroxide (TMAH) thermochemolysis of 2-arylcoumaran lignin model compounds
Journal of Analytical and Applied Pyrolysis, 2009Co-Authors: Kenichi Kuroda, Akiko Nakagawa-izumi, Tatsuya Ashitani, Koki FujitaAbstract:Abstract Phenolic 2-arylcoumarans 1 – 6 were used to examine the behaviors of β-5 subunits in lignin during Tetramethylammonium Hydroxide (TMAH) thermochemolysis. Products were monitored by gas chromatography/mass spectrometry. The process predominantly provided dimeric products with the opened hydrofuran ring. Substituent changes at the γ-position of ring A and at the 5-position of ring B had a large effect on the product compositions. 2-Arylcoumarans 1 and 6 with the γ-CH 2 OH substituent predominantly gave 2,3,3′,4′-tetramethoxystilbenes involving the elimination of the γ-CH 2 OH substituent, while 2 – 5 with the γ-CH 3 substituent gave a mixture of 2,3,3′,4′-tetramethoxy-α-methylstilbenes and α-methoxy-α-(3′,4′-dimethoxyphenyl)-β-(2,3-dimethoxyphenyl)propanes. Substituent –CH CHCH 3 on ring B remained unaffected. Substituents –CH CHCH 2 OH and –COOH on ring B produced the corresponding methyl ether and ester, respectively, by methylation. The –CH CHCHO substituent on ring B was converted to the –CHO substituent.
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Tetramethylammonium Hydroxide (TMAH) thermochemolysis of lignin: behavior of 4-O-etherified cinnamyl alcohols and aldehydes.
Journal of agricultural and food chemistry, 2005Co-Authors: Akiko Nakagawa-izumiAbstract:The thermochemolytic behavior of 4-O-etherified cinnamyl alcohols and aldehydes in lignin was investigated in the presence of Tetramethylammonium Hydroxide (TMAH) (315 °C/4 s), using veratrylglycol-β-(coniferyl alcohol) ether (1a), veratrylglycol-β-(sinapyl alcohol) ether (1b), and veratrylglycol-β-(coniferyl aldehyde) ether (2). The methylated products were monitored with gas chromatography−mass spectrometry. Dimers 1a and 1b provided the coniferyl and sinapyl alcohol dimethyl ethers consisting of three isomers, respectively. Coniferyl alcohol dimethyl ether isomers were also observed in the TMAH thermochemolysis pyrolysates of a bulk dehydrogenation polymer of coniferyl alcohol and a Japanese cedar (Cryptomeria japonica) wood. Coniferyl aldehyde methyl ether was not provided from TMAH thermochemolyses of coniferyl aldehyde, 2, a dehydrogenation polymer of coniferyl aldehyde, and the cedar wood. The former three provided veratryl aldehyde in a large abundance, instead of coniferyl aldehyde methyl ether. ...
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Tetramethylammonium Hydroxide (TMAH) thermochemolysis of lignin: behavior of 4-O-etherified cinnamyl alcohols and aldehydes.
Journal of agricultural and food chemistry, 2005Co-Authors: Kenichi Kuroda, Akiko Nakagawa-izumiAbstract:The thermochemolytic behavior of 4-O-etherified cinnamyl alcohols and aldehydes in lignin was investigated in the presence of Tetramethylammonium Hydroxide (TMAH) (315 degrees C/4 s), using veratrylglycol-beta-(coniferyl alcohol) ether (1a), veratrylglycol-beta-(sinapyl alcohol) ether (1b), and veratrylglycol-beta-(coniferyl aldehyde) ether (2). The methylated products were monitored with gas chromatography-mass spectrometry. Dimers 1a and 1b provided the coniferyl and sinapyl alcohol dimethyl ethers consisting of three isomers, respectively. Coniferyl alcohol dimethyl ether isomers were also observed in the TMAH thermochemolysis pyrolysates of a bulk dehydrogenation polymer of coniferyl alcohol and a Japanese cedar (Cryptomeria japonica) wood. Coniferyl aldehyde methyl ether was not provided from TMAH thermochemolyses of coniferyl aldehyde, 2, a dehydrogenation polymer of coniferyl aldehyde, and the cedar wood. The former three provided veratryl aldehyde in a large abundance, instead of coniferyl aldehyde methyl ether. Sinapyl aldehyde provided 3,4,5-trimethoxybenzaldehyde in a large abundance and sinapyl aldehyde methyl ether in a trace abundance. The results showed that TMAH thermochemolysis is an effective tool to obtain information on cinnamyl alcohol end groups, but is not applicable to analysis of cinnamyl aldehyde end groups.
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Tetramethylammonium Hydroxide thermochemolysis of guaiacyl–syringyl and guaiacyl dehydrogenation polymers
Organic Geochemistry, 2005Co-Authors: Kenichi Kuroda, Akiko Nakagawa-izumiAbstract:Abstract Tetramethylammonium Hydroxide thermochemolysis of lignin was investigated using guaiacyl–syringyl and guaiacyl dehydrogenation polymers. The guaiacyl–syringyl mixed polymer provided: (1) 1-(3,4-dimethoxyphenyl)-1,2,3-trimethoxypropane isomers ( 11 / 12 ) and 1-(3,4,5-trimethoxyphenyl)-1,2,3-trimethoxypropane isomers ( 15 / 16 ) as β-aryl ether subunit-derived products, (2) 2,3,3′,4′-tetramethoxy-5-(3-methoxyprop-1-enyl)stilbene ( 18 ) and 2,3,3′,4′,5′-pentamethoxy-5-(3-methoxyprop-1-enyl)stilbene ( 22 ) as β-5 subunit-derived products, (3) pinoresinol dimethyl ether ( 21 ), medioresinol dimethyl ether ( 23 ) and syringaresinol dimethyl ether ( 24 ) as β–β subunit-derived products, respectively, and (4) coniferyl alcohol dimethyl ether ( 8 ) and sinapyl alcohol dimethyl ether ( 14 ) from 4- O -linked coniferyl and sinapyl alcohols. The ratio of products stemming from β-aryl ether, β-5, β–β subunits was 23:13:64. The guaiacyl polymer provided 11 / 12 , 18 , 21 , and 8 , suggesting the same reactions occurring also in the guaiacyl polymer, although the ratio (31:32:37) of the products from β-aryl ether, β-5, β–β subunits differed.
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Thermochemolytic behavior of β–β lignin structures in the presence of Tetramethylammonium Hydroxide (TMAH)
Organic Geochemistry, 2004Co-Authors: Akiko Nakagawa-izumi, Kenichi Kuroda, Tetsuo OzawaAbstract:Abstract Tetramethylammonium Hydroxide (TMAH) thermochemolysis is widely used as an effective tool for characterizing hydrolyzable biopolymers such as lignin because it provides more products reflecting structural attributes of the polymer than conventional pyrolysis. However, its functions and the origins of the products are still unclear. Lignin model compounds containing a β–β linkage were subjected to TMAH thermochemolysis (500 °C/4 s) to investigate product distributions and reaction mechanisms. The methylated products were analyzed by gas chromatography/mass spectrometry (GC/MS). Pinoresinols (2,3) and syringaresinol (5) provided di-O-methylpinoresinol (4) and di-O-methylsyringaresinol (6), respectively, as the major product, and methylated monomers. The contribution of di-O-methylresinols was ca 80% in the pyrolyzates based on GC/MS signal areas. A guaiacyl synthetic lignin and a Japanese cedar (Cryptomeria japonica) wood lignin also yielded 4 in large and small abundances, respectively, due to the abundances of β–β subunits in the lignins and the interconnection modes of the β–β subunits with other subunits. The results demonstrated that the TMAH thermochemolysis method is a good tool for analyzing β–β subunits in lignins.
Zaifa Pan - One of the best experts on this subject based on the ideXlab platform.
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direct analysis of alkylphenols in ginkgo biloba leaves by thermochemolysis gas chromatography mass spectrometry in the presence of Tetramethylammonium Hydroxide
Journal of Analytical and Applied Pyrolysis, 2009Co-Authors: Lili Wang, Yilv Jia, Zaifa PanAbstract:Abstract Thermochemolysis–gas chromatography/mass spectrometry (GC/MS) in the presence of Tetramethylammonium Hydroxide (TMAH) was applied to the determination of alkylphenols in Ginkgo biloba leaves directly using a vertical microfurnace pyrolyzer. TMAH thermochemolysis–GC enabled the highly sensitive determination of alkylphenols including ginkgolic acids and ginkgols in G. biloba leaves as their methyl derivatives on the resulted pyrograms. On the basis of their peak areas, the contents of the alkylphenols in G. biloba leaf sample were rapidly and precisely determined without using any tedious and time-consuming pretreatment.
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Direct analysis of alkylphenols in Ginkgo biloba leaves by thermochemolysis-gas chromatography/mass spectrometry in the presence of Tetramethylammonium Hydroxide.
Journal of Analytical and Applied Pyrolysis, 2008Co-Authors: Lili Wang, Yilv Jia, Zaifa PanAbstract:Abstract Thermochemolysis–gas chromatography/mass spectrometry (GC/MS) in the presence of Tetramethylammonium Hydroxide (TMAH) was applied to the determination of alkylphenols in Ginkgo biloba leaves directly using a vertical microfurnace pyrolyzer. TMAH thermochemolysis–GC enabled the highly sensitive determination of alkylphenols including ginkgolic acids and ginkgols in G. biloba leaves as their methyl derivatives on the resulted pyrograms. On the basis of their peak areas, the contents of the alkylphenols in G. biloba leaf sample were rapidly and precisely determined without using any tedious and time-consuming pretreatment.