Determination Of Aliphatic Amines Research Articles

A long-wavelength fluorescent probe for amino compounds and its application in the determination of aliphatic amines

In this study, a simple HPLC-fluorescence detection method for aliphatic amines was developed with a novel long-wavelength BODIPY-based derivatization reagent.

Determination of aliphatic amines in food by on-fiber derivatization solid-phase microextraction with a novel zeolitic imidazolate framework 8-coated stainless steel fiber

Some harmful aliphatic diamines, e.g., putrescine (Put) and cadaverine (Cad), play important roles in food safety evaluation. In this study, we proposed on-fiber derivatization solid-phase microextraction analysis of non-volatile aliphatic diamines in fish using zeolitic imidazolate framework 8 (ZIF-8) as a solid-phase microextraction (SPME) coating. It was employed to encapsulate isobutyl chloroformate (IBCF, 40°C, 15min) for aqueous extraction of Put and Cad. After that, the derivatized aliphatic amines were thermally desorbed in the GC injection port and analyzed by GC-MS. The porous and hydrophobic ZIF-8 with high surface area can increase the IBCF loading amount and prevent it from decomposing, thus increasing the amine extraction effectiveness and sensitivity. In SIM mode and using the molecular ion for quantification, the limits of detection for Put and Cad were 27.1 and 33.2μgL−1, respectively under the optimal conditions. The fiber-to-fiber reproducibility values (RSDs) for three ZIF-8 coated fibers were less than 11.4% for both Put and Cad. The extraction with the new fiber was reproducible for at least 30 cycles without a noticeable decrease of performance (RSD<10%). The new fiber was successfully applied to the detection of putrescine and cadaverine in several fish samples and showed good recoveries (78.6–104%).

Determination of aliphatic amines by gas chromatography–mass spectrometry after in-syringe derivatization with pentafluorobenzoyl chloride

A simple and highly sensitive gas chromatographic method has been developed for the determination of low molecular weight short-chain aliphatic amines (SCAAs) after their simultaneous extraction and in-syringe derivatization with pentafluorobenzoyl chloride (PFBOC). Derivatization of the low molecular weight aliphatic amines in bicarbonate buffer of pH 10.5 with PFBOC was followed by immersed solvent microextraction. Derivatization conditions, including reagent concentration, reaction pH, ionic concentration of buffer, reaction time, stirring rate, reaction temperature and extraction solvent, have been investigated for method optimization. Linearity was studied within range of 0.15 pg ml −1–50 ng ml −1. The correlation coefficients were between 0.9934 and 0.9999. Detection limit of derivatized amines proved to be in the range of 0.117–1.527 pg ml −1, and the intraday and interday relative standard deviation (RSD) values were less than 8% with respect to peak area. The method was applied for analysis of lake, river and industrial waste water. The recoveries of extraction from lake, river and industrial waste water samples, which have been spiked with different levels of aliphatic amines, were in the range of 68–99%, 63–102% and 62–105%, respectively.

Optimization of solvent bar microextraction combined with gas chromatography for the analysis of aliphatic amines in water samples

Solvent bar microextraction (SBME) combined with gas chromatography-flame ionization detector (GC-FID), was used for preconcentration and determination of some aliphatic amines in waste water samples. The effect of different variables on the extraction efficiency was studied simultaneously using an experimental design. The variables of interest in the SBME were ionic strength, organic additive effect, sodium hydroxide concentration, stirring rate and extraction time and temperature. A Plackett-Burman design was performed for screening in order to determine the significant variables affecting the extraction efficiency. Then, the significant factors were optimized by a Box-Behnken design (BBD) and the response surface equations were derived. The optimum experimental conditions were sodium chloride concentration, 20% (w/v); sodium hydroxide concentration, 1 mol L(-1); stirring rate, 700 rpm; extraction temperature, 45 degrees C; extraction time, 30 min, and without addition of acetone. Under the optimum conditions, the preconcentration factors were between 260 and 1130. The limit of detections (LODs) ranged from 0.01 microg L(-1) (for dibutylamine) to 0.06 microg L(-1) (for N-ethyldiisopropylamine). The linear dynamic ranges (LDRs) of 0.05-800 and 0.1-600 microg L(-1) were obtained for most of the analytes. The performance of the method was evaluated for extraction and determination of aliphatic amines in waste water samples in the range of microgram per liter and satisfactory results were obtained (RSDs<13.6%).

Determination and Identification of Primary Aliphatic Amines Using 4-(1H-Phenanthro[9,10-d]Imidazol-2-yl)Benzoic Acid as Novel Pre-Column Labeling Reagent by LC with Fluorescence Detection and Atmospheric Pressure Chemical Ionization Mass Spectroscopy

4-(1H-Phenanthro[9,10-d]imidazol-2-yl)benzoic acid (PIBA), a new amine-reactive fluorescent probe was synthesized and used as a pre-column derivatizing reagent for the determination of aliphatic amines from environmetal water samples. Derivatization was successfully carried out by a condensation reaction using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride as the dehydrant. Studies on derivatization conditions indicated that the condensation reaction proceeded rapidly and smoothly in the presence of pyridine. Amines were labeled with PIBA to give the corresponding sensitively fluorescent derivatives with an excitation maximum at λex 260 nm and an emission maximum at λem 445 nm. Identification of derivatives was carried out by online APCI–MS–MS and showed an intense protonated molecular ion corresponding m/z [M + H]+ in the positive ion mode. Excellent linear responses were observed with coefficients of >0.9996. Detection limits were 6.7–27 fmol (at a signal-to-noise ratio of 3). The mean intra- and inter-assay precision for all amine levels were <2.79 and 3.85%, respectively. The established method for the determination of aliphatic amines from real water was satisfactory.

Determination of aliphatic amines by cation‐exchange chromatography with suppressed conductivity detection after solid phase extraction*

A sensitive method for the determination of underivatized aliphatic amines based on cation exchange chromatography coupled with suppressed conductivity detection scheme and solid phase extraction (SPE) procedure has been developed. A surface modified styrene divinylbenzene polymeric sorbent, based on a reversed-phase (RP) and strong cation exchange (SCX) mixed mode was used as an active material for the SPE of amines. The conductometric capabilities of several aliphatic mono- and polyamines, expressed in terms of molar sensitivity (nS/microM), were determined. The LODs, obtained without the SPE treatment, ranged between 20 and 65 nM for putrescine and 2-butylamine, respectively. The resulting calibration plots for the aliphatic amines were generally linear over about three orders of magnitude, with correlation coefficients >0.98. The LODs of amines decreased generally by one factor when SPE procedure, using BaCl(2)/H(2)SO(4) eluents, has been adopted. The proposed SPE procedure, seems to offer good results in terms of preconcentration, recoveries and cleanup of samples. The proposed methodology was successfully tested for the quantitative determination of some biogenic amines in beer and tuna.

Gas-chromatographic determination of aliphatic amines in natural surface water and wastewater

A procedure was developed for the gas-chromatographic determination of aliphatic amines C7–C20 with prederivatization by N-methyl-bis(trifluoroacetamide), in the concentration range of natural surface water, to 10−4-1 mg/L, and wastewater, to 10−3-1 mg/L. The conditions were optimized for the extraction preconcentration of aliphatic amines with toluene from natural surface water and wastewater. The detection limit for aliphatic amines at a signal-to-noise ratio of 3: 1 was 50 ng/L.

Determination of Aliphatic Amines from Soil and Wastewater of a Paper Mill by Pre‐Column Derivatization using HPLC and Tandem Mass Spectrometry (HPLC‐MS/MS)

A pre‐column derivatization method for the sensitive determination of aliphatic amines using the labeling reagent 1,2‐benzo‐3,4‐dihydrocarbazole‐9‐ethyl chloroformate (BCEOC) followed by HPLC with fluorescence detection and APCI/MS identification in positive‐ion mode has been developed. The chromophore of 2‐(9‐carbazole)‐ethyl chloroformate (CEOC) reagent was replaced by the 1,2‐benzo‐3,4‐dihydrocarbazole functional group, which resulted in a sensitive fluorescence derivatizing reagent, BCEOC, that could easily and quickly label amines. Derivatives were stable enough to be efficiently analyzed by HPLC and showed an intense protonated molecular ion corresponding m/z [M+H]+ with APCI/MS in positive‐ion mode. The collision induced dissociation of the protonated molecular ion formed characteristic fragment ions at m/z 264.1, m/z 246.0 and m/z 218.1, corresponding to the cleavages of CH2CH2O‐CO, CH2CH2‐OCO, and N‐CH2CH2O bonds. Studies on derivatization conditions demonstrated that excellent derivatization yields close to 100% were observed with a 3 to 4‐fold molar reagent excess in acetonitrile solvent, in the presence of borate buffer (pH 9.0) at 40°C for 10 min. In addition, the detection responses for BCEOC derivatives were compared with those obtained with CEOC and FMOC as labeling reagents. The ratios IBCEOC/ICEOC and IBCEOC/IFMOC were, respectively, 1.40–2.76 and 1.36–2.92 for fluorescence responses (here, I was the relative fluorescence intensity). Separation of the amine derivatives had been optimized on an Eclipse XDB‐C8 column. Detection limits calculated from an 0.10 pmol injection, at a signal‐to‐noise ratio of 3, were 18.65–38.82 fmol (injection volume 10 µL) for fluorescence detection. The relative standard deviations for intraday determination (n=6) of standard amine derivatives (50 pmol) were 0.0063–0.037% for retention times and 3.36‐6.93% for peak areas. The mean intra‐ and inter‐assay precision for all amines were <5.4% and 5.8%, respectively. The recoveries of amines ranged from 96 to 113%. Excellent linear responses were observed with correlation coefficients of >0.9994. The established method provided a simple and highly sensitive technique for the quantitative analysis of trace amounts of aliphatic amines from biological and natural environmental samples.

Determination of aliphatic amines in mineral flotation liquors and reagents by high-performance liquid chromatography after derivatization with 4-chloro-7-nitrobenzofurazan

The method described here fulfils the need for a suitable analytical method to determine the concentrations of single and mixed aliphatic amines in the range from hexylamine (C 6) to octadecylamine (C 18) in flotation test solutions and in commercial flotation collectors. Amines do not have a UV–vis spectrum in aqueous solution but by reacting an amine-containing solution with 4-chloro-7-nitrobenzofurazan solution (chloro-NBD), derivatized products (amino-NBDs) are formed which have absorbance maxima at 470 nm. Excess chloro-NBD and the amino-NBDs can be separated from each other by high-performance liquid chromatography (HPLC) and their concentrations measured with a UV–vis detector. Important variables in the derivatization stage are pH, temperature, chloro-NBD concentration, and reaction time, all of which interact with each other. A three-stage statistical procedure was used to determine the optimum conditions. In each stage, an 8-test design was used in which a high and low limit was set for each variable, and the chromatogram peak area of the derived amino-NBD was measured. The optimum derivatization conditions established were pH 8.9, chloro-NBD concentration 0.20% (w/v), temperature 70 °C, and reaction time 60 min. Optimum elution conditions for chromatography were an eluent containing 80% (v/v) acetonitrile in aqueous solution containing 40 mM acetic acid at pH 4.5. With a flow rate of 2.0 ml/min, dodecylamine had a retention time of about 3 min, whereas octadecylamine had a retention time of 44 min. Straight-line calibration curves were obtained up to at least 200 ppm of amine in solution. The lower limit of detection was estimated to be 0.05 μM (10 ppb) with a signal to noise ratio of 3. No interfering substances were found. The method was successfully applied to the analysis of solutions from an actual flotation test and to a solid commercial amine.

Determination of aliphatic amines in water by gas chromatography using headspace solvent microextraction

The possibility of applying headspace microextraction into a single drop for the determination of amines in aqueous solutions is demonstrated. A 1 μl drop of benzyl alcohol containing 2-butanone as an internal standard was suspended from the tip of a micro syringe needle over the headspace of stirred sample solutions for extraction. The drop was then injected directly into a GC. The total chromatographic determination was less than 10 min. Optimization of experimental conditions (sampling time, sampling temperature, stirring rate, ionic strength of the solution, concentration of reagents, time of extraction and organic drop volume) with respect to the extraction efficiency were investigated and the linear range and the precision were also examined. Calibration curves yielded good linearity and concentrations down to 2.5 ng ml −1 were detectable with R.S.D. values ranging from 6.0 to 12.0%. Finally, the method was successfully applied to the extraction and determination of amines in tap and river water samples. This system represents an inexpensive, fast, simple and precise sample cleanup and preconcentration method for the determination of volatile organic compounds at trace levels.

Determination of aliphatic amines using N-succinimidyl benzoate as a new derivatization reagent in gas chromatography combined with solid-phase microextraction

A simple, selective and sensitive approach was developed for the quantitation of aliphatic amines in lake water applying a new reagent ( N-succinimidyl benzoate, SIBA), synthesized in the laboratory of the authors. Derivatization of the n-C 1–C 6 aliphatic monoamines and dimethylamine in aqueous solution with SIBA was followed by headspace solid-phase microextraction (SPME). Derivatives were identified by gas chromatography-mass spectrometry and determined by gas chromatography-flame ionization detection. Both derivatization and SPME conditions have been optimized. Derivatizations were performed in borate buffer (pH 8.8), at 60 °C for 22 min. SPME was carried out from saturated sodium chloride solution, at 80 °C for 60 min, desorption at 250 °C for 2 min. Detection limit of derivatized amines proved to be 0.13–7.2 nmol/l, while recovery of amines from lake water samples, in the concentration range of 100–200 μg/l, varied from 94.1 to 102.7%.

Determination of Aliphatic Amines by High Performance Liquid Chromatography with Amperometric Detection after Derivatization with Phenylisothiocyanate

Determination of Aliphatic Amines by High Performance Liquid Chromatography with Amperometric Detection after Derivatization with Phenylisothiocyanate

Determination of Aliphatic Amines in Water Using Derivatization with Fluorescein Isothiocyanate and Capillary Electrophoresis/Laser-Induced Fluorescence Detection

Detection-oriented derivatization of aliphatic amines and amine functional groups in compounds of environmental interest was studied using fluorescein isothiocyanate (FITC) with separation/determination by capillary electrophoresis/laser-induced fluorescence. Determinative levels down to 10 ppb were studied in deionized and environmental waters. Practical detection limits of 30 to 100 ppb or more were realized, depending on analyte and water source. Criteria were developed to compare results to desired performance in a derivatization method. FITC was judged to be a moderately successful reagent with drawbacks including extensive by-products, lack of specificity to analyte class, requirement to study each potential analyte carefully, and derivatization limits near 30 ppb. Advantages include low cost of reagent, ease in handling, and synthesis of an ionized derivative for free zone electrophoresis.

Polymers with reactive functions as sampling and derivatizing agents—Part 2. Polymeric pentafluorobenzoylating reagent for gas chromatographic–mass spectrometric determination of aliphatic amines

Polystyrene resins containing mixed carbonic–pentafluorobenzoic anhydride functions have been synthesized and utilized for the derivatization of a number of primary and secondary aliphatic amines in high yields, under mild conditions. The pentafluorobenzamides formed were identified and quantified by use of capillary column gas chromatography–mass spectrometry with selected ion monitoring in the negative ion chemical ionization mode. The lower limit of detection for butylamine as a model amine was 2 pg per 2 µl injection and the calibration graph showed linearity in the range 5–250 ng ml–1 with a correlation coefficient of 0.9956. Primary and secondary amines were chosen as substrates for the evaluation and application of the polymeric reagent in view of their good nucleophilicity and their prevalence as pollutants in the workplace.

Determination of aliphatic amines in air by membrane enrichment directly coupled to a gas chromatograph

A method is described for the determination of shortchain aliphatic amines in ambient air based on impinger sampling in dilute H2SO4, selective enrichment across a PTFE gas membrane and quantification by gas chromatography. The enrichment step is carried out in a flow system directly connected to the chromatograph. The separation is performed on a packed column with nitrogen selective detection. The enrichment per sample volume was in the range 7.3 to 8.2 mL−1 for C1−C6 amines. Detection limits were ca 3–10 nM with enrichment of a 2.9 mL liquid sample. After impinger sampling of 5 m3 air in 10 mL absorption solution, this corresponds, to 0.4–0.8 ng/m3 (ca 0.2–0.5 ppt by volume) in air.

Determination of aliphatic amines by gas and high-performance liquid chromatography

Aliphatic amines, such as mono-, di- and trimethylamine ( MMA, DMA, TMA) and trimethylamine N-oxide ( TMAO), are produced by bacterial degradation of trimethylalkylammonium compounds, such as choline, acetylcholine, carnitine and γ-betaines. This degradation can be environmental, intestinal or faecal 1.2. This paper describes an analytical investigation by gas chromatography ( GC) with flame ionization detection ( FID) or thermionic specific detection ( TSD) and by high-performance liquid chromatography ( HPLC) with conductimetric, refractive index ( RI) and electrochemical detection ( ED) for the simultaneous determination of the above amines, mainly applied to biological samples such as urine, and an assay procedure adopted consisting in chemical reduction of TMAO to TMA, followed by evaluation of the latter by GC in order to determine the TMAO.

Determination of Aliphatic Amines in Air by On-Line Solid-Phase Derivatization with HPLC-UV/FL

An easy, rapid, and efficient method using on-line solid-phase derivatization in HPLC is developed for the trace determination of aliphatic amines in air. Some fundamental studies on stop-flow, on-line, solid-phase derivatizations in HPLC are also investigated, such as optimization of the reaction detection HPLC system and band broadening. Air is sampled with silica gel tubes from different sites, including sewage areas, fish cleaning and processing rooms, and an organoleptic lab of the U.S. Food & Drug Administration (FDA). The trapped amines are desorbed with an acidic aqueous-organic solution, followed by pH adjustment of the eluates to pH 10. The resulting solution is directly injected into an on-line, precolumn, solid-phase derivatization and reversed-phase HPLC-UV/FL system, not requiring any further sample workup steps. The percent derivatizations are as high as 88 +/- 5% (n = 3) for primary amines, and 75 +/- 4% (n = 3) for diethylamine under optimized conditions (60 degrees C for 10 min). The recoveries for all amines are above 90%. The method is validated by a single-blind, spiked experiment with 1.1-4.4% relative standard deviation (RSD) in the range of 15-47 ppm. These results are confirmed by a GC-FID method performed in another lab. Amines are quantitated via calibration plots, with final concentrations from 0.02 to 0.38 mg/m3 air. It is suggested that this newer approach for the determination of amines and polyamines, using polymeric solid-phase reagents on-line, precolumn in HPLC, should prove generally successful for other amines and other sample types in the future.

Separation and determination of aliphatic amines by high-performance liquid chromatography with ultraviolet detection

Utilisation d'une reaction modifiee de Schotten-Bauman, formant des composes absorbants dans le spectre UV

Determination of aliphatic amines in air by reversed-phase high-performance liquid chromatography using 1-naphthyl isocyanate derivatives

Determination de traces de n-propylamine, n-butylamine et allylamine dans l'air sous forme de derives d'isocyanate de naphtyl-1

7-Oxo-7H-benzimidazo[2,1-a]benz[d,e]isoquinoline-9-sulphonyl chloride as a new fluorescence reagent for identification and determination of aliphatic amines

Absorption and fluorescence properties have been studied of a new fluorescence reagent - 7-oxo-7H-benzimidazo[2,1-a]benz[d,e]isoquinoline-9-sulphonyl chloride and the corresponding sulphonamides derived from aliphatic amines. The fluorescence intensity is temperature-independent in the range 0-35 °C and depends linearly on concentration of the sulphonamides in the range 6 . 10-9 to 1 . 10-6 mol l-1. TLC separation of the sulphonamides is good, the yields of elution being 95%, which allows application of the procedure to determination of the amines.