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Daradoumis J, Müller MD, Neckermann P, Asbach B, Schrödel S, Thirion C, Wagner R, thor Straten P, Holst PJ, Boilesen D. Preferential Expansion of HPV16 E1-Specific T Cells from Healthy Donors' PBMCs after Ex Vivo Immunization with an E1E2E6E7 Fusion Antigen. Cancers (Basel) 2023; 15:5863. [PMID: 38136407 PMCID: PMC10741473 DOI: 10.3390/cancers15245863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 12/08/2023] [Accepted: 12/13/2023] [Indexed: 12/24/2023] Open
Abstract
Persistent human papillomavirus (HPV) infection is responsible for practically all cervical and a high proportion of anogenital and oropharyngeal cancers. Therapeutic HPV vaccines in clinical development show great promise in improving outcomes for patients who mount an anti-HPV T-cell response; however, far from all patients elicit a sufficient immunological response. This demonstrates a translational gap between animal models and human patients. Here, we investigated the potential of a new assay consisting of co-culturing vaccine-transduced dendritic cells (DCs) with syngeneic, healthy, human peripheral blood mononuclear cells (PBMCs) to mimic a human in vivo immunization. This new promising human ex vivo PBMC assay was evaluated using an innovative therapeutic adenovirus (Adv)-based HPV vaccine encoding the E1, E2, E6, and E7 HPV16 genes. This new method allowed us to show that vaccine-transduced DCs yielded functional effector T cells and unveiled information on immunohierarchy, showing E1-specific T-cell immunodominance over time. We suggest that this assay can be a valuable translational tool to complement the known animal models, not only for HPV therapeutic vaccines, and supports the use of E1 as an immunotherapeutic target. Nevertheless, the findings reported here need to be validated in a larger number of donors and preferably in patient samples.
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Affiliation(s)
- Joana Daradoumis
- InProTher ApS, Bioinnovation Institute, Ole Maaløes Vej 3, 2200 Copenhagen, Denmark; (M.D.M.); (P.J.H.)
- Department of Immunology and Microbiology, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
| | - Mikkel Dons Müller
- InProTher ApS, Bioinnovation Institute, Ole Maaløes Vej 3, 2200 Copenhagen, Denmark; (M.D.M.); (P.J.H.)
- Department of Immunology and Microbiology, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
| | - Patrick Neckermann
- Institute of Medical Microbiology & Hygiene, Molecular Microbiology (Virology), University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
| | - Benedikt Asbach
- Institute of Medical Microbiology & Hygiene, Molecular Microbiology (Virology), University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
| | | | | | - Ralf Wagner
- Institute of Medical Microbiology & Hygiene, Molecular Microbiology (Virology), University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
- Institute of Clinical Microbiology and Hygiene, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg, Germany
| | - Per thor Straten
- Department of Immunology and Microbiology, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
- Center for Cancer Immune Therapy, Department of Oncology, Copenhagen University Hospital, 2730 Copenhagen, Denmark
| | - Peter Johannes Holst
- InProTher ApS, Bioinnovation Institute, Ole Maaløes Vej 3, 2200 Copenhagen, Denmark; (M.D.M.); (P.J.H.)
| | - Ditte Boilesen
- Department of Immunology and Microbiology, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
- Loma Therapeutics ApS, Bioinnovation Institute, Ole Maaløes Vej 3, 2200 Copenhagen, Denmark
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Boilesen DR, Neckermann P, Willert T, Müller MD, Schrödel S, Pertl C, Thirion C, Asbach B, Wagner R, Holst PJ. Efficacy and Synergy with Cisplatin of an Adenovirus Vectored Therapeutic E1E2E6E7 Vaccine against HPV Genome-Positive C3 Cancers in Mice. Cancer Immunol Res 2023; 11:261-275. [PMID: 36534088 DOI: 10.1158/2326-6066.cir-22-0174] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 08/25/2022] [Accepted: 12/14/2022] [Indexed: 12/24/2022]
Abstract
Human papillomavirus (HPV) infections are the main cause of cervical and oropharyngeal cancers. As prophylactic vaccines have no curative effect, an efficient therapy would be highly desired. Most therapeutic vaccine candidates target only a small subset of HPV regulatory proteins, namely, E6 and E7, and are therefore restricted in the breadth of their immune response. However, research has suggested E1 and E2 as promising targets to fight HPV+ cancer. Here, we report the design of adenoviral vectors efficiently expressing HPV16 E1 and E2 in addition to transformation-deficient E6 and E7. Vaccination elicited vigorous CD4+ and CD8+ T-cell responses against all encoded HPV16 proteins in outbred mice and against E1 and E7 in C57BL/6 mice. Therapeutic vaccination of C3 tumor-bearing mice led to significantly reduced tumor growth and enhanced survival for both small and established tumors. Tumor biopsies revealed increased numbers of tumor-infiltrating CD8+ T cells in treated mice. Cisplatin enhanced the effect of therapeutic vaccination, accompanied by enhanced infiltration of dendritic cells into the tumor. CD8+ T cells were identified as effector cells in T-cell depletion assays, seemingly under regulation by FoxP3+CD4+ regulatory T cells. Finally, therapeutic vaccination with Ad-Ii-E1E2E6E7 exhibited significantly enhanced survival compared with vaccination with two peptides each harboring a known E6/E7 epitope. We hypothesize that this difference could be due to the induction of additional T-cell responses against E1. These results support the use of this novel vaccine candidate targeting an extended set of antigens (Ad-Ii-E1E2E6E7), in combination with cisplatin, as an advanced strategy to combat HPV+ cancers.
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Affiliation(s)
- Ditte Rahbæk Boilesen
- Centre for Medical Parasitology, The Panum Institute, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.,InProTher ApS, Copenhagen, Denmark
| | - Patrick Neckermann
- Institute of Medical Microbiology and Hygiene, Molecular Microbiology (Virology), University of Regensburg, Regensburg, Germany
| | | | - Mikkel Dons Müller
- Centre for Medical Parasitology, The Panum Institute, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.,InProTher ApS, Copenhagen, Denmark
| | | | | | | | - Benedikt Asbach
- Institute of Medical Microbiology and Hygiene, Molecular Microbiology (Virology), University of Regensburg, Regensburg, Germany
| | - Ralf Wagner
- Institute of Medical Microbiology and Hygiene, Molecular Microbiology (Virology), University of Regensburg, Regensburg, Germany.,Institute of Clinical Microbiology and Hygiene, University Hospital Regensburg, Regensburg, Germany
| | - Peter Johannes Holst
- Centre for Medical Parasitology, The Panum Institute, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.,InProTher ApS, Copenhagen, Denmark
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Müller MD, Holst PJ, Nielsen KN. A Systematic Review of Expression and Immunogenicity of Human Endogenous Retroviral Proteins in Cancer and Discussion of Therapeutic Approaches. Int J Mol Sci 2022; 23:ijms23031330. [PMID: 35163254 PMCID: PMC8836156 DOI: 10.3390/ijms23031330] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 01/20/2022] [Accepted: 01/21/2022] [Indexed: 02/06/2023] Open
Abstract
Human endogenous retroviruses (HERVs) are remnants of ancient retroviral infections that have become fixed in the human genome. While HERV genes are typically silenced in healthy somatic cells, there are numerous reports of HERV transcription and translation across a wide spectrum of cancers, while T and B cell responses against HERV proteins have been detected in cancer patients. This review systematically categorizes the published evidence on the expression of and adaptive immune response against specific HERVs in distinct cancer types. A systematic literature search was performed using Medical Search Headings (MeSH) in the PubMed/Medline database. Papers were included if they described the translational activity of HERVs. We present multiple tables that pair the protein expression of specific HERVs and cancer types with information on the quality of the evidence. We find that HERV-K is the most investigated HERV. HERV-W (syncytin-1) is the second-most investigated, while other HERVs have received less attention. From a therapeutic perspective, HERV-K and HERV-E are the only HERVs with experimental demonstration of effective targeted therapies, but unspecific approaches using antiviral and demethylating agents in combination with chemo- and immunotherapies have also been investigated.
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Affiliation(s)
- Mikkel Dons Müller
- Institute of Immunology and Microbiology, University of Copenhagen, Blegdamsvej 3, 2200 Copenhagen N, Denmark;
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Raschke H, Meier M, Burken JG, Hany R, Müller MD, Van Der Meer JR, Kohler HP. Biotransformation of various substituted aromatic compounds to chiral dihydrodihydroxy derivatives. Appl Environ Microbiol 2001; 67:3333-9. [PMID: 11472901 PMCID: PMC93025 DOI: 10.1128/aem.67.8.3333-3339.2001] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The biotransformation of four different classes of aromatic compounds by the Escherichia coli strain DH5alpha(pTCB 144), which contained the chlorobenzene dioxygenase (CDO) from Pseudomonas sp. strain P51, was examined. CDO oxidized biphenyl as well as monochlorobiphenyls to the corresponding cis-2,3-dihydro-2,3-dihydroxy derivatives, whereby oxidation occurred on the unsubstituted ring. No higher substituted biphenyls were oxidized. The absolute configurations of several monosubstituted cis-benzene dihydrodiols formed by CDO were determined. All had an S configuration at the carbon atom in meta position to the substituent on the benzene nucleus. With one exception, the enantiomeric excess of several 1,4-disubstituted cis-benzene dihydrodiols formed by CDO was higher than that of the products formed by two toluene dioxygenases. Naphthalene was oxidized to enantiomerically pure (+)-cis-(1R,2S)-dihydroxy-1,2-dihydronaphthalene. All absolute configurations were identical to those of the products formed by toluene dioxygenases of Pseudomonas putida UV4 and P. putida F39/D. The formation rate of (+)-cis-(1R,2S)-dihydroxy-1,2-dihydronaphthalene was significantly higher (about 45 to 200%) than those of several monosubstituted cis-benzene dihydrodiols and more than four times higher than the formation rate of cis-benzene dihydrodiol. A new gas chromatographic method was developed to determine the enantiomeric excess of the oxidation products.
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Affiliation(s)
- H Raschke
- Swiss Federal Institute for Environmental Sciences and Technology (EAWAG), CH-8600 Dübendorf, Switzerland
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Poiger T, Buser HR, Müller MD. Comment on "Chemical-biological treatment of pyrene" by Y. Zeng, P. K. A. Hong and D. A. Warrek, Water Research 34(4), 1157-1172 (2000). Water Res 2001; 35:573-577. [PMID: 11229014 DOI: 10.1016/s0043-1354(00)00386-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Affiliation(s)
- T Poiger
- Swiss Federal Research Station for Fruit-Growing, Viticulture and Horticulture, P.O. Box 185, CH-8820 Wädenswil, Switzerland.
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Poiger T, Buser HR, Müller MD. Photodegradation of the pharmaceutical drug diclofenac in a lake: pathway, field measurements, and mathematical modeling. Environ Toxicol Chem 2001; 20:256-263. [PMID: 11351424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Vertical concentration profiles of diclofenac were measured in Lake Greifensee (Switzerland) under mixed (February/December) and stratified (July) lake conditions. The concentrations ranged from 1 to 12 ng/L and were lower in summer than in winter, especially near the lake surface, pointing to an efficient elimination of diclofenac by photodegradation in the lake. Laboratory experiments confirmed the rapid photodegradation of diclofenac in water when exposed to sunlight. First-order reaction rates varied seasonally according to actual solar radiation (half-lives, tau = 0.2-1.7 h). The initial photoproduct was 8-chlorocarbazole-1-acetic acid, which photodegraded even faster than the parent compound. Carbazole-1-acetic acid, previously reported as the main photoproduct, was only formed in the presence of a H-source, such as methanol. In the absence of a H-source and of air, hydroxycarbazole-1-acetic acid was formed. However, hydroxycarbazole-1-acetic acid was not observed in the presence of air and, thus, under conditions similar to those in a lake, likely because of its rapid further photooxidation. Computer simulations using a one-dimensional lake model taking actual solar radiation and flushing data of the lake into account confirmed that photolysis is the predominant elimination pathway for diclofenac in Lake Greifensee. These calculations further showed that the expected concentrations of the photoproduct 8-chlorocarbazole-1-acetic acid are less than the current detection limits of approximately 3 ng/L.
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Affiliation(s)
- T Poiger
- Swiss Federal Research Station, CH-8820 Wädenswil, Switzerland.
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Müller MD, Poiger T, Buser H. Isolation and identification of the metolachlor stereoisomers using high-performance liquid chromatography, polarimetric measurements, and enantioselective gas chromatography. J Agric Food Chem 2001; 49:42-49. [PMID: 11170558 DOI: 10.1021/jf000857f] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Because of the presence of two chiral elements (an asymmetrically substituted carbon and a chiral axis), the herbicide metolachlor consists of four stereoisomers stable at ambient temperature with aSS-, aRS-, aSR-, and aRR-configurations (aSS, the isomer with aS,1'S-configuration, etc.). Metolachlor, initially introduced into the market as the racemic product containing all four stereoisomers, is currently being replaced worldwide by S-metolachlor, the product enantiomerically enriched with the herbicidally active 1'S-isomers (aSS, aRS). The isomer-specific analysis of metolachlor requires not only enantioselective ("chiral") analytical techniques but also suitable reference compounds. In this study, two of the four metolachlor isomers were isolated from rac-metolachlor in enantio- (ee > 98%) and diastereomerically pure forms by a combination of achiral and chiral high-performance liquid chromatography (HPLC). The two isomers were identified as the aSS- and the aRR-isomers by polarimetric measurements, in reference to previous data. The two isomers were then thermally equilibrated to 1:1 mixtures of the aSS/aRS and aRR/aSR diastereomers, respectively, so that analytical data of all four metolachlor isomers became available; they were then used to identify these isomers in technical products by chiral high-resolution gas chromatography (HRGC). The kinetics of the thermally induced interconversion of the atropisomers was studied and the consequences, such as for GC analysis, are discussed. A comparison of on-column and split/splitless injection indicated that the latter technique results in significant isomerization prior to separation and, therefore, cannot be used for accurate isomer analysis.
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Affiliation(s)
- M D Müller
- Swiss Federal Research Station, CH-8820 Wädenswil, Switzerland
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Buser HR, Hany R, Müller MD, Poiger T, Rentsch D. Comment on influence of the chemical environment on metolachlor conformations. J Agric Food Chem 2000; 48:4448-4449. [PMID: 10995378 DOI: 10.1021/jf0005420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Buser HR, Haglund P, Müller MD, Poiger T, Rappe C. Discrimination and thermal degradation of toxaphene compounds in capillary gas chromatography when using split/splitless and on-column injection. Chemosphere 2000; 41:473-479. [PMID: 10819216 DOI: 10.1016/s0045-6535(99)00481-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Technical toxaphene and a 22-component Reference Mixture were analyzed using capillary gas chromatography with split/splitless injection (SSL) and on-column injection (OC). In both techniques, electron-capture, negative ionization mass spectrometry (ECNI-MS) was used for detection of chlorobornanes, chlorocamphenes and related compounds. Significant discrimination of highly chlorinated congeners was observed as a result of incomplete transfer of these compounds from the vaporizer to the analytical column when using SSL. This resulted in a much lower response for nona- and decachloro congeners than when using OC. In addition, several toxaphene components, especially the chlorobornanes with gem dichloro substitution on the six-member carbon ring, undergo thermal degradation when using SSL. Some of these congeners are major components of technical toxaphene, but generally are not present, except at low concentrations, in environmental and biological samples. Therefore, technical toxaphene may be discriminated and/or degraded differently than toxaphene compounds in environmental samples when using SSL. This results in significant bias of the quantitative data when using the technical material as a reference. OC suffers much less from these deficiencies and, therefore, is a preferable technique for toxaphene analysis.
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Affiliation(s)
- H R Buser
- Swiss Federal Research Station, Wädenswil.
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Abstract
We studied the degradation of technical toxaphene in anaerobic sewage sludge from a municipal waste water treatment plant. Chlorobornanes, chlorocamphenes and related compounds were rapidly degraded, with degradation rates in the order of decachloro>nonachloro>octochloro>heptachloro approximately = hexachloro compounds. The half-lives of individual congeners ranged from <1 day to several days. We also studied the degradation of technical toxaphene in previously sterilized sludge (control), and found it was slower than in the anaerobic sludge. The chlorobornanes that degraded most rapidly in the non-sterilized anaerobic sludge were those with gem chloro substitution on the 6-member carbon-ring, including the toxic congeners, Toxicant A and B. Non-gem chloro substituted congeners, like the biologically persistent P26 and P50, also degraded, but less rapidly. Toxaphene degradation in sewage sludge proceeded primarily via reductive dechlorination, leading to HxSed, HpSed, TC2 and other persistent metabolites. Enantioselective determinations indicated little, if any, enantioselectivity in the formation and/or degradation of these compounds. The isomer and enantiomer profiles of the hexa-, hepta-, and octachlorobornanes are similar to those observed in sediment from the Baltic Sea, suggesting that technical toxaphene is the source of these compounds and that its composition was changed via similar anaerobic degradation pathways.
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Affiliation(s)
- H R Buser
- Swiss Federal Research Station, Wädenswil
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Zipper C, Bolliger C, Fleischmann T, Suter MJ, Angst W, Müller MD, Kohler HP. Fate of the herbicides mecoprop, dichlorprop, and 2,4-D in aerobic and anaerobic sewage sludge as determined by laboratory batch studies and enantiomer-specific analysis. Biodegradation 2000; 10:271-8. [PMID: 10633543 DOI: 10.1023/a:1008396022622] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Aerobic degradation experiments with the racemic mixtures of mecoprop and dichlorprop revealed that activated sludge collected from the aeration tank of a municipal waste water treatment plant degraded both enantiomers of mecoprop and dichlorprop within 7 days, albeit in an enantioselective manner; the (S) enantiomers were preferentially degraded. Mecoprop, dichlorprop, and 2,4-D were completely metabolized under aerobic conditions, as shown by the 86-98% elimination of dissolved organic carbon. Under anaerobic conditions, the concentration of 2,4-D decreased exponentially with a first-order reaction rate constant of 0.24 per day and without a lag-phase. After an incubation time of 17 days, 2,4-D was completely removed. 2,4-Dichlorophenol was the main metabolite of anaerobic 2,4-D degradation; only traces of 4-chlorophenol were detected. In contrast, the chiral phenoxypropionic acid herbicides mecoprop and dichlorprop persisted under anaerobic conditions during 49 days of incubation.
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Affiliation(s)
- C Zipper
- Swiss Federal Institute for Environmental Science and Technology, Dübendorf, Switzerland
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Müller MD, Bosshardt HP. Enantiomer resolution and assay of propionic acid-derived herbicides in formulations by using chiral liquid chromatography and achiral gas chromatography. J Assoc Off Anal Chem 1988; 71:614-7. [PMID: 3391971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Enantiomers of 6 propionic acid-derived herbicides in the form of their esters were resolved using liquid chromatography with a chiral column. Free acids are converted to methyl esters by means of a BF3-catalyzed reaction. Chromatographic resolutions for 6 of 8 herbicides investigated were in the range of 2 to 4. The method was applied for the simultaneous determination of mecoprop and 2,4-D content and individual mecoprop enantiomers in 2 formulations containing racemic and R-mecoprop in mixture with 2,4-D. Precision and accuracy of content determination was comparable to standard methods, and enantiomer contents were in good agreement with declared values. The enantiomers of dichlorprop and mecoprop were also resolved as diastereomeric menthyl esters by achiral high resolution gas chromatography (HRGC). HRGC data on enantiomer composition were in good agreement with those from the LC method and other data.
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Affiliation(s)
- M D Müller
- Swiss Federal Research Station, Wädenswil
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Schmid PP, Müller MD. Trace level detection of chlorinated paraffins in biological and environmental samples, using gas chromatography/mass spectrometry with negative-ion chemical ionization. J Assoc Off Anal Chem 1985; 68:427-30. [PMID: 4019363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A method is described for detection of chlorinated paraffins (CPs) in biological and environmental samples. Sample preparation includes sulfuric acid treatment followed by adsorption chromatography on alumina, which yields the CPs in one fraction that is almost free of interfering material. Using gas chromatography/mass spectrometry with negative-ion chemical ionization, the limit of detection is 5 ng (corresponding to the lower ppb range). CP levels of 30 ppm, 200 ppb, and 5 ppb were found in sewage sludge, human fat, and sediment, respectively.
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