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PubMed2006

Semi-covalent imprinted polymer using propazine methacrylate as template molecule for the clean-up of triazines in soil and vegetable samples.

A semi-covalent imprinted polymer was prepared by precipitation polymerisation using propazine methacrylate as template molecule, ethylene glycol dimethacrylate as cross-linker and toluene as porogen. After removal of propazine by basic hydrolysis of the covalent bond, the optimum loading, washing and elution conditions for the solid-phase extraction of the selected triazines were established. The binding sites present in the polymeric matrix were characterised by fitting the experimental results of several rebinding studies to the Langmuir-Freundlich isotherm. Subsequently, an analytical methodology based on molecularly imprinted solid-phase extraction (MISPE) was developed for the determination of several triazinic herbicides in soil and vegetable samples. Following this procedure, a good degree of clean-up of the sample extracts was easily achieved, allowing the HPLC-UV determination of selected triazines in complex samples at low concentration levels.

Food Contamination↗

PubMed2006

Removal of triazine herbicides from freshwater systems using photosynthetic microorganisms.

The uptake of the triazine herbicides, atrazine and terbutryn, was determined for two freshwater photosynthetic microorganisms, the green microalga Chlorella vulgaris and the cyanobacterium Synechococcus elongatus. An extremely rapid uptake of both pesticides was recorded, although uptake rate was lower for the cyanobacterium, mainly for atrazine. Other parameters related to the herbicide bioconcentration capacity of these microorganisms were also studied. Growth rate, biomass, and cell viability in cultures containing herbicide were clearly affected by herbicide uptake. Herbicide toxicity and microalgae sensitivity were used to determine the effectiveness of the bioconcentration process and the stability of herbicide removal. C. vulgaris showed higher bioconcentration capability for these two triazine herbicides than S. elongatus, especially with regard to terbutryn. This study supports the usefulness of such microorganisms, as a bioremediation technique in freshwater systems polluted with triazine herbicides.

Atrazine↗

PubMed2006

Effects of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) metabolites on cricket (Acheta domesticus) survival and reproductive success.

The effect of two major hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) metabolites, hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX) and hexahydro-1,3,5-trinitroso-1,3,5-triazine (TNX), on cricket (Acheta domesticus) survival and reproduction was studied. RDX metabolites did not have adverse effects on cricket survival, growth, and egg production. However, MNX and TNX did affect egg hatching. MNX and TNX were more toxic in spiked-sand than in topical tests. TNX was more toxic to egg than MNX. Developmental stage and exposure time affected hatching. After 30 days exposure to MNX or TNX, the EC20, EC50, and EC95 were 47, 128, and 247 microg/g for TNX, and 65, 140, and 253 microg/g for MNX in topical tests. The ECs for 20, 50, and 95 were 21, 52, and 99 microg/g for MNX, and 12, 48, and 97 microg/g for TNX in sand. No gross abnormalities in cricket nypmhs were observed in all experiments indicating that neither TNX or MNX is teratogenic in this assay.

Animals↗

PubMed2004

Retention mechanism of analytes in the solid-phase extraction process using molecularly imprinted polymers. Application to the extraction of triazines from complex matrices.

Two molecularly imprinted polymers (MIPs), prepared in dichloromethane with terbutylazine and ametryn as template molecules, were evaluated for the selective extraction of triazines from complex matrices. Various parameters affecting extraction recoveries on MIPs were studied in order to obtain an optimized extraction procedure allowing to reduce non-specific interactions. In order to test the selectivity of the MIPs, the same procedure was applied to the extraction of compounds possessing the same polarity and size as the triazines. By means of molecular modeling, the effects of the electric charge distribution and of the size of the molecules on the retention mechanism were studied. The value of capacity for terbutylazine MIP was also measured. At last, the high selectivity resulting from the use of MIPs was clearly demonstrated by their applications to the clean-up of grape juice and soil extracts spiked with triazines. In addition, the soil extract was cleaned-up by immunoextraction allowing the comparison of both approaches in terms of selectivity.

Models, Molecular↗

PubMed2002

Synthesis of variously 9,9-dialkylated octahydropyrimido [3,4-a]-s-triazines with potential antifungal activity.

9,9-Dialkyloctahydropyrimido[3,4-a]-s-triazines were synthesized by iminodimethylation reaction between a 5,5-dialkyl-6-aminopyrimidine-2.4(3H,5H)-dione, a substituted aniline and two moles of formaldehyde. The synthesis of.5,5-dialkyl-6-aminopy-rimidinedione consisted of the condensation of urea with ethyl 2,2-dialkylcyanoacetates. 18 Octahydropyrimido[3,4-a]-s-triazines were synthesized and compounds resulting from a supplementary aminomethylation were also obtained. Most of these compounds were tested for antifungal activity in vitro. Only 9.9-dibutyl-6,8-dioxo-3(2-chlorophenyl)2,3,4,5,6,7,8,9-octahydropyrimido[3,4-a]-s-triazine showed some activity against Microsporum canis.

Antifungal Agents↗

PubMed1988

High-performance liquid chromatography of s-triazines and their degradation products using ultraviolet photometric and amperometric detection.

The chromatographic behaviour of eighteen s-triazine derivatives has been studied in a reversed-phase system with a Separon SIC 18 stationary phase and a mobile phase of aqueous sodium dihydrogenphosphate and methanol. The dependences of the capacity factors on the methanol content, the pH and the ionic strength have been obtained. Ultraviolet photometric detection can generally be used whereas amperometric detection with a carbon-fibre array electrode is useful for selective detection of s-triazine hydroxy derivatives, but with a sensitivity poorer than that of photometric detection. The method has been applied to a study of the photolysis of s-triazines and the effect of the substituents and the pH on the photolysis rate.

Biodegradation, Environmental↗

PubMed1983

Application of affinity partitioning in an aqueous two-phase system to the investigation of triazine dye enzyme interactions.

Affinity partitioning in an aqueous two-phase system by using triazine dye-substituted polyethylene glycol and dextran was applied in the investigation of the affinity of kinases, dehydrogenases and aminotransferases to twelve triazine dyes. From the alteration of the partition coefficient (K) of the enzymes in the two-phase system in the presence or absence of dye-liganded polyethylene glycol, expressed as delta log K, quantitative data for the affinity of the enzymes to various triazine dyes were obtained. Optimal conditions for the purification of enzymes by applying dye-protein interaction were derived.

Chromatography, Affinity↗

PubMed1998

Inter-laboratory validation of solid-phase microextraction for the determination of triazine herbicides and their degradation products at ng/l level in water samples.

The accuracy and precision of solid-phase microextraction (SPME) were validated in an inter-laboratory study including ten laboratories for the analysis of triazine herbicides and their metabolites at ng/l level in aqueous samples. The SPME conditions were optimised in order to obtain maximum sensitivity. Especially, salt addition and choice of the SPME fibre coated with Carbowax-divinylbenzene increased the sensitivity. The average detection limits were in the range from 4 to 24 ng/l for the triazine herbicides, and 20 and 40 ng/l for desisopropylatrazine and desethylatrazine, respectively. The average r2 values of the calibration curves were above 0.99 for all of the analytes. The statistical data treatment was performed in accordance with the International Standardisation Organisation (ISO) standard 5725. Relative repeatability standard deviations between 6 and 14% and relative reproducibility standard deviations between 10 and 17% were found. The determined concentrations of the reference sample compared well to the "true" values, thus proving the good accuracy of the method. It is concluded that SPME is a reliable technique for the quantitative analysis of water samples containing triazine herbicides in concentrations around the European limit of 100 ng/l for individual pesticides in drinking water.

Calibration↗

PubMed1999

The mammary tumor response in triazine-treated female rats: a threshold-mediated interaction with strain and species-specific reproductive senescence.

Triazine herbicides are among the most heavily used agricultural pesticides. Although they possess a very low acute toxicity in animals, a mammary tumor response has been consistently observed in Sprague-Dawley (SD) female rats following chronic oral dosing of atrazine and simazine at and above maximum tolerated doses. However, a substantial collection of detailed research has clearly shown that triazines are not genotoxic or mutagenic, nor do they possess estrogenic agonist activity that might promote mammary tumor growth. Examination of estrous cycling records of atrazine-treated SD rats revealed a premature appearance of persistent estrous episodes, beyond the prevalent occurrence normally seen in untreated, aging SD rats. A significant correlation has been found between early or severe estrous cycle disruption of atrazine-treated rats and the early appearance of mammary tumors. In studies using SD female rats fed atrazine for 6 months, then ovariectomized and administered an estrogen-containing silastic s.c. implant, a deficient luteinizing hormone surge was observed at a 400 parts per million (ppm) dose, but not at 25 or 50 ppm. Because SD rats exhibiting persistent estrus also have a prolonged elevation of estrogen secretion, it is proposed that the triazine-associated mammary tumor response is promoted by the test animal's own estrogen from ovarian follicles that fail to ovulate because gonadotropin surge sufficiency is blocked by the high dose of herbicide. It is further proposed that, because reproductive senescence in SD rats is fundamentally different from menopause in women, the animal response to dosing, as well as the enormous requisite dosing level, establishes a safety margin of very low risk to human health from this mode of action.

Aging↗

PubMed2002

Anaerobic biotransformation of RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) by aquifer bacteria using hydrogen as the sole electron donor.

RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) is a nitramine explosive that has contaminated soil and groundwater at military installations throughout the US. Although anaerobic RDX metabolism has been reported, the process is not well understood, as past studies have typically involved complex, undefined media with multiple potential electron donors and acceptors. In this study, bacteria enriched from RDX-contaminated aquifer sediments consumed RDX in a defined, bicarbonate-buffered, anaerobic medium containing hydrogen as the sole electron donor and RDX as a potential electron acceptor and sole nitrogen source. RDX was not consumed in live controls that did not contain hydrogen. Transient formation of mononitroso- and dinitroso-RDX metabolites (hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine and hexahydro-1,3-dinitroso-5-nitro-1,3,5-triazine, respectively) was documented by liquid chromatography-mass spectrometry. However, studies with 14C-labeled RDX suggested that mineralization to carbon dioxide was negligible (<2%), which is consistent with cometabolic transformation. Several lines of evidence suggest that the RDX-transforming bacteria under study were homoacetogens, including correlations between RDX consumption and acetate production. Methanogens were unlikely to be responsible for RDX metabolism, as the presence of 2-bromoethanesulfonate, an inhibitor of methanogenesis, did not appear to affect RDX metabolism. The presence of nitrate reversibly halted RDX metabolism, whereas ammonium had no discernible effect, which implies that: (i) nitrate, which commonly occurs in RDX-contaminated groundwater, may inhibit in situ RDX metabolism, and (ii) although RDX may act as both a nitrogen source and cometabolic electron sink, the latter role predominates, as RDX reduction will proceed regardless of whether or not a more favorable nitrogen source is present.

Bacteria, Anaerobic↗

PubMed2002

Synthesis and antitumor activity of novel 2-amino-4-(3,5,5-trimethyl-2-pyrazolino)-1,3,5-triazine derivatives.

The syntheses and antitumor activities of novel 2-amino-4-(3,5,5-trimethyl-2-pyrazolino)-1,3,5-triazine derivatives 4-38 are described. All the compounds prepared were screened at the National Cancer Institute (NCI) for their activities against a panel of 60 tumor cell lines and relationships between structure and antitumor activity in vitro are discussed. The triazines 11, 16, 20, 23, 23 and 34-38 exhibited modest or fairly high activity against one or more human tumor cell lines. Prominent compound with remarkable activity (log GI50, < - 8.00- - 5.00) to all investigated cell lines and highly potent (log GI50 < - 8.00- - 7.64) against some cell lines of Leukemia (CCRF-CEM, K-562, RPMI-8226, SR), CNS Cancer (SF-539) and Breast Cancer (T-47D) was 2-[2-amino-4-(3,5,5-trimethyl-2-pyrazolino)-1,3,5-triazin-6-yl]-3-(5-nitro-2-thienyl)acrylonitrile (25).

Antineoplastic Agents↗

PubMed2000

Cytogenetic studies of three triazine herbicides. II. In vivo micronucleus studies in mouse bone marrow.

Atrazine, simazine, and cyanazine are widely used preemergence and postemergence triazine herbicides that have made their way into the potable water supply of many agricultural communities. Although there are several contradictory genotoxicity studies in the literature, our previous in vitro studies with human lymphocytes showed that atrazine, simazine, and cyanazine did not induce sister chromatid exchanges (SCEs) or chromosome aberrations (CAs) up to the limits of solubility in aqueous medium using 0.5% dimethyl sulfoxide. To expand upon these results and to ensure that our in vitro findings could be replicated in an in vivo system, mice were treated with each triazine by two intraperitoneal injections, 24h apart. The animals were sacrificed and the bone marrow removed for micronucleus (MN) analysis, 24h after the last injection. Two to four independent trials were performed for MN analysis in polychromatic erythrocytes, and in some trials the spleen was removed, cultured, and analyzed for SCEs and CAs. None of the triazines investigated induced MN in the bone marrow, even at doses that caused significant bone marrow suppression and/or death. These results indicate that atrazine, simazine, and cyanazine are not genotoxic as measured by the bone marrow MN assay in mice following high dose exposures.

Animals↗

PubMed2000

Cytogenetic studies of three triazine herbicides. I. In vitro studies.

Atrazine, simazine, and cyanazine are widely used pre-emergence and post-emergence triazine herbicides that have made their way into the potable water supply of many agricultural communities. Because of this and the prevalence of contradictory cytogenetic studies in the literature on atrazine, simazine, and cyanazine, a series of in vitro experiments was performed to investigate the ability of these three triazines to induce sister chromatid exchanges (SCEs) and chromosome aberrations (CAs) in human lymphocyte cultures. Our results showed that all three triazines failed to produce any significant increases in SCEs or CAs up to the limits of solubility [using 0.5% dimethyl sulfoxide (DMSO)]. Our results are discussed in light of contradictory results in the literature.

Atrazine↗

PubMed2003

Triazines facilitate neurotransmitter release of synaptic terminals located in hearts of frog (Rana ridibunda) and honeybee (Apis mellifera) and in the ventral nerve cord of a beetle (Tenebrio molitor).

Three triazine herbicides, atrazine, simazine and metribuzine, and some of their major metabolites (cyanuric acid and 6-azauracil) were investigated for their action on synaptic terminals using three different isolated tissue preparations from the atria of the frog, Rana ridibunda, the heart of the honeybee, Apis mellifera macedonica, and the ventral nerve cord of the beetle, Tenebrio molitor. The results indicate that triazines facilitate the release of neurotransmitters from nerve terminals, as already reported for the mammalian central nervous system. The no observed effect concentration, the maximum concentration of the herbicide diluted in the saline that has no effect on the physiological properties of the isolated tissue, was estimated for each individual preparation. According to their relative potency, the three triazines tested can be ranked as follows: atrazine (cyanuric acid), simazine>metribuzine (6-azauracil). The action of these compounds on the cholinergic (amphibians, insects), adrenergic (amphibian) and octopaminergic (insects) synaptic terminals is discussed.

Animals↗

PubMed2002

Triazine-human serum albumin association: thermodynamic approach and sodium effect.

Human serum albumin (HSA) serves as a carrier protein to transport triazine herbicides to molecular targets. In this paper, a theoretical treatment was developed to describe the HSA-triazine herbicides association. A determination of the association constant, K, as well as the degree of complexation n(c) (the percent of complex guest) was carried out. Enthalpy-entropy compensation was also analyzed in relation to this mathematical model to confirm the herbicide complexation behavior with HSA. The role of the sodium cation (Na(+)) on this association was investigated. It was expected that the sodium ion would act on the herbicide-HSA association process by modifying the surface tension of the bulk solvent and increase the K and n(c) values. The results showed that for patients who suffer from Na(+) desequilibrium, the triazine-HSA binding would change and as well the toxicological effect of these herbicides.

Herbicides↗

PubMed2001

Solubility of triazine pesticides in pure and modified subcritical water.

Solubility measurements in pure and modified water serve as a basis for optimizing the subcritical water extraction of target analytes such as food contaminants. The solvent strength of the water is affected by both the system's temperature and the amount and type of cosolvent modifier that is added to the water, which causes a reduction in the dielectric constant of water. In the present work, the solubilities of the triazine pesticides atrazine, cyanazine, and simazine were measured in pure and modified water at temperatures ranging from 50 to 125 degrees C and at a pressure of 50 atm. The solubility data were obtained using a static solubility apparatus with on-line liquid chromatographic (LC) detection. By increasing the temperature of the water, the solubilities of the triazine pesticides increased approximately 3-fold in pure water for each 25 degrees C temperature increment. Cyanazine was 5 times more soluble than atrazine and an order of magnitude more soluble than simazine at 100 degrees C. The solubility of atrazine was also measured in ambient and hot water modified with ethanol and urea. At 100 degrees C, the solubility of atrazine is doubled when the water is modified with urea, and is increased over an order of magnitude when ethanol is used as modifier. The data, therefore, indicate that adding a cosolvent to water in addition to increasing the system temperature increases the solubilities of triazine pesticides in subcritical water. It was further determined that the solutes do not thermally degrade or hydrolyze at the temperatures reported in this study.

Atrazine↗

PubMed2001

Molecular recognition in a propazine-imprinted polymer and its application to the determination of triazines in environmental samples.

An analytical methodology for the determination of triazines in environmental samples incorporating a molecularly imprinted solid-phase extraction (MISPE) process using a propazine-imprinted polymer was developed. Two different polymers were prepared using acetonitrile or toluene as porogen, and their optimum loading, washing, and elution conditions were established. Although both polymers were able to recognize several chlorotriazines (propazine, atrazine, simazine, desethylatrazine, and desisopropylatrazine), the polymer prepared in toluene showed the best performance and was also capable of recognizing a methylthiotriazine (prometryn). A binding study carried out in this polymer demonstrated that it possesses heterogeneous binding sites with different binding abilities. From this study, it was also concluded that desethylatrazine and desisopropylatrazine displace the other triazines at high concentrations, including the template molecule. The accuracy and selectivity of the MISPE process developed was verified using a certified reference material for drinking water containing atrazine and simazine among other commonly used pesticides. Finally, the MISPE procedure was successfully applied to the cleanup of drinking and groundwater, soil, and corn sample extracts, and the triazines were determined by micellar electrokinetic chromatography.

Chromatography, Micellar Electrokinetic Capillary↗

PubMedDate not supplied

Spatially addressed synthesis of amino- and amino-oxy-substituted 1, 3,5-triazine arrays on polymeric membranes.

Effective spatially addressed parallel assembly of trisamino- and amino-oxy-1,3,5-triazines was achieved by applying the SPOT-synthesis technique on cellulose and polypropylene membranes. In addition to developing a suitable linker strategy and employing amines and phenolate ions as building blocks, a highly effective microwave-assisted nucleophilic substitution procedure at membrane-bound monochlorotriazines was developed. The 1,3, 5-triazines obtained could be cleaved in parallel from the solid support by TFA vapor to give compounds adsorbed on the membrane surface in a conserved spatially addressed format for analysis and screening. The reaction conditions developed were employed for the synthesis of 8000 cellulose-bound 1,3,5-triazines which were probed in parallel for binding to the anti-transforming growth factor-alpha monoclonal antibody Tab2 in order to identify epitope mimics.

Amines↗