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PubMed2003

Determination of low-molecular-mass quaternary ammonium compounds by capillary electrophoresis and hyphenation with mass spectrometry.

The determination of quaternary ammonium ions by capillary electrophoresis (CE) is reviewed. The analytes include tetraalkylammonium and alkylbenzyldimethylammonium compounds frequently used as antiseptic and antibacterial agents as well as in various household products, several plant growth regulators and herbicides, by-products in bile acid sequestrants, and a range of anticholinergic drugs. Besides direct and indirect UV detection, hyphenation with electrospray mass spectrometry is particularly suited for quaternary ammonium ions and may lower the detection limits by two orders of magnitude. In comparison with established liquid chromatographic techniques, CE may exhibits superior separation efficiency. Applications in routine analysis have demonstrated that CE is reliable and robust enough to represent a real alternative to chromatography.

Electrophoresis, Capillary↗
PubMed1976

Phospholipid phase transitions. Effects of n-alcohols, n-monocarboxylic acids, phenylalkyl alcohols and quaternary ammonium compounds.

The interactions of a series of alcohols, acids and quaternary ammonium salts with a phosphatidylcholine-water model biomembrane (dipalmitoyl phosphatidycholine) system have been studied using differential scanning calorimetry. In particular the effects of these molecules upon the lipid endothermic phase transitions were investigated over a range of concentrations. A variety of effects was observed. (a) Those molecules which shift or broaden the main lipid transition can also remove the pretransition endotherm. (b) n-Alcohols and n-monocarboxylic acids containing the same number of carbon atoms have very similar effects at molar concentrations up to 40%. Those molecules containing 12 or more carbon atoms raise the main lipid phase transition whilst those molecules containing 10 or less carbon atoms lower this transition temperature. (c) The phase diagram of stearoyl alcohol in the phosphatidylcholine-water system shows the formation of lipid-alcohol complexes. (d) Alkyl trimethyl ammonium bromides showed behaviour which differs considerably from n-alcohols and n-carboxylic acids of the same chain length. (e) Other alkyltrialkyl and tetraalkylammonium bromides show that a variety of effects on the lipid phase transition can be obtained. (f) With the homologous series of phenyl-alkyl alcohols from benzyl alcohol to 4-phenyl butanol increasing the number of methylenes between the terminal OH and the benzene ring leads to greater interaction between solute and bilayer. The range of different effects obtained with the compounds studied offers a means for introducing various degrees and types of perturbation into membrane systems.

Alcohols↗
PubMed2004

Application of internal quality control to the analysis of quaternary ammonium compounds in surface and groundwater from Andalusia (Spain) by liquid chromatography with mass spectrometry.

A method has been developed for the simultaneous determination of paraquat (PQ), deiquat (DQ), chlormequat (CQ) and mepiquat (MQ) in water samples by liquid chromatography (LC) coupled with electrospray ionization mass spectrometry (MS). The LC separations of the target compounds, as well as their MS parameters, were optimized in order to improve selectivity and sensitivity. Separation was carried out in a Xterra C8 column, using as mobile phase methanol-heptafluorobutyric acid (HFBA) in isocratic mode. The molecular ion was selected for the quantitation in selected ion monitoring (SIM) mode. Off-line solid-phase extraction (SPE) was applied with silica cartridges in order to preconcentrate the compounds from waters. Detection limits were in the range 0.02-0.40 microg l(-1). Recovery range varied between 89 and 99.5% with precision values lower than 6%. The method has been applied successfully to the analysis of both surface and groundwater samples from agricultural areas of Andalusia (Spain), using well defined internal quality control (IQC) criteria. The results revealed the presence of deiquat and paraquat in some samples.

Chromatography, High Pressure Liquid↗
PubMed1979

Haemodynamic effects of the quaternary ammonium compound QX 572 in anaesthetized cats. III. Interactions with adrenergic beta-adrenoceptor blockade.

The positive cardiac chronotropic effects of the antiarrhythmic compound, QX 572, in anaesthetized cats has been shown mainly to be due to a release of catecholamines from sympathetic nerve-endings. Furthermore, these undesired effects of QX 572 on heart rate were decreased by adrenergic beta blockade in the animals. In the present study it was found that an adrenergic beta-blockade did not reveal any cardiodepressive effects of QX 572, that in the normal animals might have been masked by the effects of the drug-induced catecholamine-release.

Adrenergic beta-Antagonists↗
PubMed1979

Haemodynamic effects of the quaternary ammonium compound QX 572 in anaesthetized cats. I. Cardiac chronotropic effects.

The haemodynamic effects of the antiarrhythmic compound, QX 572, have been studied in anaesthetized cats. It was found that QX 572 increased the heart rate and decreased the blood pressure of the cats during the infusion of the drug. A slight increase in blood pressure was seen after the infusion was terminated. The same results have been obtained in patients. Experiments on cats pretreated with propranolol or reserpine showed that infusions of QX 572 caused an increase in heart rate by increasing the sympathetic activity in the cats. It is also shown that changes in vagal tone may contribute to the effects of QX 572 on the heart rate.

Animals↗
PubMed1988

Central pharmacological activity of a quaternary ammonium compound in streptozotocin diabetic mice.

Possible changes in blood-brain barrier (BBB) function as a result of diabetes were investigated by assessing antagonism of morphine analgesia in diabetic mice by methylnaltrexone (MeNTX), an opioid receptor blocker that does not cross the BBB when administered subcutaneously (SC). In streptozotocin (STZ)-treated diabetic mice--but not vehicle-treated, non-diabetic mice--treatment with SC MeNTX significantly reduced morphine analgesia. In vehicle-treated, non-diabetic mice, morphine analgesia was antagonized by MeNTX administered intracerebroventricularly and by SC naltrexone, which crosses the BBB. Reduction of STZ-induced hyperglycemia by insulin reversed the effectiveness of SC MeNTX in antagonizing morphine analgesia. We hypothesize that in STZ diabetic mice, MeNTX was able to cross the BBB and block brain opioid receptors.

Animals↗
PubMed2005

Trospium chloride: an anticholinergic quaternary ammonium compound for the treatment of overactive bladder.

The International Continence Society has defined overactive bladder (OAB) as urinary urgency, with or without urge urinary incontinence, usually with urinary frequency and nocturia. Approximately 17% of men and women in the US report OAB symptoms, which can affect quality of life. Trospium chloride, which has recently been introduced in the US as Sanctura, has been prescribed for > 10 years in Europe as, for example, Spasmo-lyt, Regurin and Spasmex. Trospium chloride has been shown to be effective in relieving OAB symptoms, and has a favourable safety profile, showing < 1% difference for all adverse events compared with placebo, except for dry mouth, constipation and headache. Metabolic drug-drug interactions are unlikely, given that trospium chloride is not metabolised by cytochrome P450 isozymes. The fast-acting efficacy of trospium chloride, coupled with its good safety profile and tolerability, make it an important new option for treatment of OAB.

Benzilates↗
PubMed1984

Direct quantitation of antiseptic quaternary ammonium compounds by fast atom bombardment mass spectrometry.

The medicinally important quaternary ammonium salts benzyldimethyltetradecylammonium chloride (BDTA), cetylpyridinium chloride and benzethonium chloride, all afford, under fast atom bombardment (FAB) mass spectrometric conditions, abundant and persistent [M-Cl]+ species usefully amenable to quantitative analysis with the aid of thioglycerol as a liquid FAB matrix. The use of BDTA as an internal standard allowed a direct, precise and accurate determination of cetylpyridinium and benzethonium chlorides, either as pure samples or in dosage forms, in the concentration range 0.05-2 mg/ml.

Journal Article↗
PubMed2000

Triterpene saponins, quaternary ammonium compounds, phosphatidyl cholines, and amino acids in the pronotal and elytral secretions of Platyphora opima and Desmogramma subtropica.

Secretions of the pronotal and elytral glands of adults of the chrysomelid beetle Platyphora opima from Panama have been shown to contain two oleanane triterpene saponins: the known 3-O-beta-D-glucopyranosyl-(1-->3)-beta-D-glucuronopyranosyl-oleano lic acid-28-O-beta-D-glucopyranoside and compound 1, whose structure was established as 3-O-beta-D-glucopyranosyl-(1-->3)-beta-D-glucuronopyranosyl-29- hydrox yoleanolic acid-28-O-beta-D-glucopyranoside by a combination of 1D and 2D NMR methods (COSY, HMQC, HMBC, and TOCSY) and FABMS. The secretions also contained N,N,N-trimethylcadaverine and its 1, 2-dehydro derivative 3, as well as the nicotinamide derivative 4. Secretions of Desmogramma subtropica, also from Panama, contained as sole triterpene derivative 3-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucuronopyranosyl-24- hydrox yoleanolic acid (2), together with glutamic acid, glutamine, pyroglutamic acid, and arginine. A mixture of phosphatidylcholines was also present in the secretions of both species.

Amino Acids↗
PubMed1984

Nasal drug delivery system of a quaternary ammonium compound: clofilium tosylate.

The blood levels of the [14C]clofilium ion in rats after various routes of administration of clofilium tosylate were compared. The results indicate that the blood levels after nasal administration were not statistically different from levels after intravenous administration (p greater than 0.05). Administration by the oral route resulted in considerably lower blood levels. Nasal administration of clofilium tosylate appeared to be superior to oral administration. Histological examinations of nasal mucosa were conducted. At the lower concentration, mild necrosis was observed, and large areas of mucosa were unaffected. However, necrosis of large areas of mucosa occurred after exposure to the higher concentration. Levels of radioactivity in heart, liver, lung, and kidney tissue, as a function of time, were also studied. Unlike the blood levels after nasal administration, the levels of radioactivity were persistent in heart tissue. The data suggest that the [14C]clofilium ion and/or metabolite concentrate in the heart and that blood levels of radioactivity may not be an accurate index of cardiac levels or biological response.

Administration, Intranasal↗
PubMed1978

Lidocaine and the quarternary ammonium compound QX-572 in acute myocardial infarction. A comparative study.

Patients with suspected or proven acute myocardial infarction complicated by ventricular arrhythmias not corrected by lidocaine therapy (bolus dose 100 mg followed by infusion 2 mg/min) were treated either with an increased dose of lidocaine (bolus dose 50 mg followed by infusion 3 mg/min) or with 600 mg N,N-bis dimethylammonium chloride (QX-572, Astra, Sweden) as an i.v. infusion during 30 min (3 patients) or 60 min (13 patients). In the lidocaine group the arrhythmias were controlled in 6 out of 15 patients, in the QZ-572 group in 12 out of 16, a difference that is not statistically significant. However, the frequency of side-effects was significantly higher (p less than 0.001) in the QX-572 group (15 out of 16 patients). They were also more severe, including pronounced tachycardia and hypertension. It is concluded that despite the high antiarrhythmic effect of QX-572, an increase of the lidocaine dose would be safer and preferable in the clinical situation studied.

Acute Disease↗
PubMed1999

In vitro efficacy of N-duopropenide, a recently developed disinfectant containing quaternary ammonium compounds, against selected gram-positive and gram-negative organisms.

OBJECTIVE: To study the efficacy of N-duopropenide against various gram-positive and gram-negative organisms. SAMPLE POPULATION: One field strain each of Pasteurella multocida subsp multocida, Staphylococcus aureus, Listeria monocytogenes, and L ivanovii, and 2 field strains of Escherichia coli. PROCEDURE: Strains were tested with and without serum as organic matter, using quantitative suspension and carrier tests. Six concentrations of active ingredient (0.005, 0.01, 0.05, 0.11, 0.27, and 0.55%) and 6 contact times (15 and 30 seconds and 1, 3, 5, and 10 minutes) were studied for each. RESULTS: Globally, N-duopropenide was more effective in suspension tests than in carrier tests, and when organisms were suspended in saline solution rather than serum. Under the most disadvantageous conditions (carrier test with serum), a concentration of 0.55% N-duopropenide acting for only 15 seconds was effective in inactivating P multocida subsp multocida and was even more effective against the 2 Listeria species tested. For E coli strains, the same concentration also was effective, but after 10 minutes of contact. On the other hand, N-duopropenide was unable to inactivate the S aureus strain in the carrier test with serum, a concentration of 0.55% for 10 minutes was necessary to inactivate it without organic matter; however, N-duopropenide was highly effective against this organism in the suspension test, even with serum. CONCLUSION: N-duopropenide was highly effective in vitro against 5 of the most commonly encountered organisms in clinical veterinary medicine and, consequently, might be a good choice in control measures against common pathogenic organisms in modern production systems.

Aldehydes↗
PubMed1975

Haemodynamic effects of the antiarrhythmic quaternary ammonium compound QX-572 in man.

The haemodynamic effects of N, N-bis(phenyl-carbamoylmethyl) dimethylammonium chloride (QX-572) in man were studied. A controlled study was performed to rule out a possible influence of the catheterization procedure as such on the results. Ten patients with mild to moderate aortic regurgitation were studied: based on clinical data the patients were divided into 2 groups of 5. Randomly it was decided that one group should constitute a control group receiving saline while the second group received QX-572 , MG/KG BODY WEIGHT. In both groups the administration was performed as a slow intravenous infusion during 30 minutes. Heart rate, pressures in brachial artery and right atrium, cardiac output, stroke volume, and systemic vascular resistance were determined before, during, and up to 30 minutes after completion of placebo or QX-572. These variable remained stable in the control group while QX-572 produced an increase in heart rate most pronounced at the end of the infusion period. A transient decrease in systolic and mean brachial artery pressure during the infusion, and during the same period a decrease in right atrial pressure. Cardiac output and systemic vascular resistance were unchanged by QX-572 but they were not measured during the infusion when the changes in pressures were most pronounced. QX-572 was thought to act as a peripheral vasodilator during the infusion. Left ventricular contractility was studied by means of pressure curves obtained from a catheter tip manometer placed in the left ventricle. The first derivative of the isovolumic left ventricular pressure at the highest level (45mmHg) common to all patients was used (dp/dt-45). No significant difference could be observed when comparing mean changes of dp/dt-45 for the two groups. In the control group there was a slight but significant increase in dp/dt-45 during the time of observation. In the QX-572 group the results varied between individuals. Two of the patients differed from all other patients in the control and QX-572 groups showing a decrease in dp/dt-45 which, when most pronounced at the end of the infusion period, was -31 and -28 per cent of the preinfusion levels, respectively. This decrease probably reflects reduction of contractility. It was concluded that QX-572 in a dose of 8 mg/kg body weight did not have any major haemodynamic drawbacks.

Adult↗
PubMed1969

Resistance of Pseudomonas to quaternary ammonium compounds. I. Growth in benzalkonium chloride solution.

Resistant cells of Pseudomonas aeruginosa and a waterborne Pseudomonas sp. (strain Z-R) were able to multiply in nitrogen-free minimal salts solution containing various concentrations of commercially prepared, ammonium acetate-buffered benzalkonium chloride (CBC), a potent antimicrobial agent. As the CBC concentration increased, growth increased until a point was reached at which the extent of growth leveled off or was completely depressed. Minimal salts solutions of pure benzalkonium chloride (PBC) containing no ammonium acetate did not support bacterial growth. When ammonium acetate was added to PBC solutions in the same concentrations found in CBC solutions, growth patterns developed that were comparable to those found with CBC. Likewise, (NH(4))(2)SO(4) added to PBC solutions supported growth of both organisms. P. aeruginosa was initially resistant to CBC levels of 0.02% and it was adapted to tolerate levels as high as 0.36%. Strain Z-R was naturally resistant to 0.4% CBC. Since ammonium acetate, carried over by the CBC used in drug formulations and disinfectant solutions, has the potential to support the growth of resistant bacteria and thus make possible the risk of serious infection, it is suggested that regulations allowing the presence of ammonium acetate in CBC solution be reconsidered.

Acetates↗
PubMed1997

Spin-lattice relaxation in ammonium compounds with a complex molecular dynamics.

Expressions are derived for the initial relaxation rate 1/T1 of protons and deuterons of nontunnelling NH4 and ND4 groups reorienting about various symmetry axes in solids. The reorientation rates are modified by a trigonal, tetragonal or monoclinic distortion of the predominantly cubic hindering potential. When the rates differ sufficiently from each other, two T1 minima are observed with a characteristic ratio. Experiments were performed in NH4VO3, (NH4)2S2O8, (NH4)2PtCl4, and their deuterated modifications, which all exhibit two T1 minima. In NH4VO3 and ND4VO3 the relaxation and spectral data agree rather well with the model of trigonal distortion. Also (NH4)2S2O8 has a preferred threefold axis but there, the large tunnel splitting of protons has to be taken into account before an agreement is reached. All the purely reorientational models fail with (NH4)2PtCl4, where, instead, the ammonium groups are proposed to be ordered into domains at low temperatures. The groups inside the domains and boundary regions give rise to the high- and low-temperature T1 minima, respectively. The boundaries are also believed to give rise to the narrow component in the deuteron spectrum at low temperatures. Evidence for a proton tunnelling frequency of 32 MHz is found in (NH4)2PtCl4.

Algorithms↗
PubMed1985

Nitrosation of quaternary ammonium compounds in vivo in the Wistar rat.

Animals dosed orally with nitrite (1.5 X 10(-3) mol/kg) and nonyl dimethylbenzylammonium bromide (2.9 X 10(-4) mol/kg) exhibit liver damage within two hours; cetyl trimethylammonium bromide plus nitrite was not significantly hepatotoxic. Both nonyl dimethylbenzyl ammonium bromide and cetyl trimethylammonium bromide were demethylated by rat-liver microsomal preparations; substrate concentrations of 1 mM or more were inhibitory. Bile from rats given i.p. doses of cetyl trimethylammonium bromide, nonyl dimethylbenzylammonium bromide or dodecyl dimethylbenzylammonium bromide contains only metabolites, no unchanged compounds were detected.

Administration, Oral↗
PubMedDate not supplied

Efficacy of a new quarternary ammonium compound against TB.

Ten of 12 strains of Mycobacteria (11 M. tuberculosis, 1 M. bovis) including 7 resistant strains were found to be sensitive to tetradecyl-dimethyl-benzyl-ammonium fluoride (TDBAF) at a concentration of 15-7.75 micrograms/ml (end point 10 micrograms/ml). A single multi-resistant strain of M. tuberculosis and a culture of M. bovis were also sensitive but at a slightly higher level.

Antitubercular Agents↗
PubMed1994

Allosteric effects of the alkane-bis-ammonium compound W84 and of tacrine on [3H]pirenzepine binding at M1-receptors in rat cerebral cortex.

The bis-quaternary W84, hexamethylene-bis-[dimethyl-(3-phthalimidopropyl)-ammonium bromide], is a potent allosteric modulator of M2-cholinoceptors. In this study we aimed at quantifying its allosteric effect on the dissociation of [3H]pirenzepine from M1-cholinoceptors in rat cerebral cortex and to measure the effects on association and equilibrium binding of [3H]pirenzepine. For sake of comparison tacrine was included which is known to be a potent allosteric modulator of [3H]pirenzepine binding to M1-receptors. Under control conditions (3 mM MgHPO4, 50 mM Tris-HCl, pH 7.4, 23 degrees) [3H]pirenzepine binding was characterized by KD = 5 nM and Bmax = 965 fmol/mg membrane protein, the rate constants amounting to k+1 = 5.0 microM-1 x min-1 and k-1 = 0.031 min-1. W84 and tacrine reduced [3H]pirenzepine binding concentration-dependently with IC50-values of 1.9 microM and 2.6 microM, respectively. [3H]pirenzepine association was inhibited by the compounds with EC50,ass = 1.8 microM for W84 and EC50,ass = 2.4 microM for tacrine. The concentrations reducing the dissociation rate by 50% amounted to EC50,diss = 21 microM for W84 and to EC50,diss = 54 microM for tacrine. Compared with W84, the dose-reponse curves of tacrine for the investigated effects were significantly steeper. In conclusion, WS84 affected [3H]pirenzepine binding to M1-receptors allosterically with a higher potency than tacrine but probably by a different mechanism.

Allosteric Regulation↗