ABSTRACT
Plant volatile organic compounds (VOCs) are organic chemicals that plants release as part of their natural biological processes. Various plant tissues produce VOCs, including leaves, stems, flowers, and roots. VOCs are essential in plant communication, defense against pests and pathogens, aroma and flavor, and attracting pollinators. The study of plant volatiles has become an increasingly important area of research in recent years, as scientists have recognized these compounds' important roles in plant physiology. As a result, there has been a growing interest in developing methods for collecting and analyzing plant VOCs. HS-SPME-GC-MS (headspace solid-phase microextraction-gas chromatography-mass spectrometry) is commonly used for plant volatile analysis due to its high sensitivity and selectivity. This chapter describes an efficient method for extracting and identifying volatile compounds by HS-SPME coupled with GC-MS in tomato fruits.
Subject(s)
Fruit , Gas Chromatography-Mass Spectrometry , Solanum lycopersicum , Solid Phase Microextraction , Volatile Organic Compounds , Solanum lycopersicum/chemistry , Fruit/chemistry , Volatile Organic Compounds/isolation & purification , Gas Chromatography-Mass Spectrometry/economics , Gas Chromatography-Mass Spectrometry/methods , Solid Phase Microextraction/economics , Solid Phase Microextraction/methodsABSTRACT
Data processing and data extraction are the first, and most often crucial, steps in metabolomics and multivariate data analysis in general. There are several software solutions for these purposes in GC-MS metabolomics. It becomes unclear which platform offers what kind of data and how that information influences the analysis's conclusions. In this study, selected analytical platforms for GC-MS metabolomics profiling, SpectConnect and XCMS as well as MestReNova software, were used to process the results of the HS-SPME/GC-MS aroma analyses of several blackberry varieties. In addition, a detailed analysis of the identification of the individual components of the blackberry aroma club varieties was performed. In total, 72 components were detected in the XCMS platform, 119 in SpectConnect, and 87 and 167 in MestReNova, with automatic integral and manual correction, respectively, as well as 219 aroma components after manual analysis of GC-MS chromatograms. The obtained datasets were fed, for multivariate data analysis, to SIMCA software, and underwent the creation of PCA, OPLS, and OPLS-DA models. The results of the validation tests and VIP-pred. scores were analyzed in detail.
ABSTRACT
In this study, headspace solid-phase micro-extraction (HS-SPME) coupled with GC-MS was used to analyze the trend of volatile compounds in fresh and oxidative infant nutrition package. Among the volatile compounds, aldehydes and ketones, alcohols, lipids, cycloalkenes, alkanes, alkenes, aromatic hydrocarbons, oxygenated compound were identified. A total of 65 volatile compounds were detected in the fresh nutrition package, whereas 9 new volatile compounds were detected during the accelerated oxidation process, which was oxidized at 45 °C for 4 weeks. The main components of the rancid flavor formed and the relative content of volatile substances gradually changed during the accelerated oxidation process. The volatile substances hexanal, nonanal, and 2-pentylfuran substantially increased. Linalool, α-terpineol, d-limonene, and 1-methoxy-nonane presented an evidently downward trend. The relative content of the newly formed compound 3-hydroxy-2-methylpyran-4-one during the oxidation process was always large, its relative content initially increased, then decreased, and finally increased again. The formation of rancid flavor of the nutrient package was speculated to have been formed by the interaction of hexanal, nonanal, 2-pentylfuran, and 3-hydroxy-2-methylpyran-4-one.
ABSTRACT
The potential of Lactiplantibacillus plantarum ZJ316 (ZJ316) as a starter culture for quality improvement and microbial community regulation in pickled mustard fermentation was elucidated in this study. Our results show that ZJ316 can deter the occurrence of nitrite peaks and maintain the nitrite content of pickled mustard at a low level (0.34 mg/kg). The headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry results indicate that ZJ316 gives a good flavor to pickled mustard. According to the 16S rDNA results, Firmicutes were the predominant microbiota after inoculation with ZJ316, and the abundances of Citrobacter, Enterobacter, and Proteus decreased simultaneously. In addition, antibacterial activity analysis showed that the supernatant of pickled mustard inoculated with ZJ316 had a significant inhibitory effect on Staphylococcus aureus D48, Escherichia coli DH5α, and Listeria monocytogenes LM1. In conclusion, L. plantarum ZJ316 has potential for use as an ideal starter in the process of vegetable fermentation.
ABSTRACT
Callus and microshoot cultures were established for Chiliadenus montanus (Vhal.) Brullo. (Asteraceae), a medicinal plant known for producing volatile organic compounds (VOCs). Callus induction was achieved successfully by culturing leaf explants on full-strength Murashige and Skoog medium (MS) supplemented with 2.2 µM 2, 4-dichlorophenoxy acetic acid (2,4-D) and 6.9 µM kinetin (Kin). Successful direct shoot regeneration was achieved using nodal explants cultured onto half-strength MS media supplemented with 1.4 µM Gibberellic Acid (GA3) and 4.4 µM 6-Benzylaminopurine (BAP). Indirect microshoots were successfully regenerated using callus cultured on MS media supplemented with 8.8 µM BAP, 2.2 µM Zeatin, and 1.4 µM GA3 followed by culturing on MS media supplemented with 8.8 µM BAP and 0.5 µM naphthalene acetic acid (NAA). Using wild plant aerial parts, callus and microshoots samples, VOCs were extracted successfully using Headspace Solid-Phase Micro-Extraction (HS-SPME) and analyzed by gas chromatography-mass spectrometry (GC-MS). In wild plant extracts, sesquiterpene hydrocarbons were found to be predominant with the following principal components: Alloaromadendrene (11.92%), trans-Cadina-1(6),4-diene (7.54%), and α-caryophyllene (6.77%). The analysis of in vitro microshoots revealed high levels of oxygenated monoterpenes with cis-Myrtanol (16.62%), and ß-Cyclocitral (14.3%) as the main components. Callus extract was dominated by monoterpene hydrocarbons and the main compounds identified were (Z)-ß-Ocimene (22.27%), p-Cymene (15.13%), and α-pinene (13.78%). In conclusion, an efficient in vitro production system of VOCs in C. montanus was established that can be used in the future for boosting their production without endangering wild plants.
ABSTRACT
The volatile compounds of eight peach varieties (Prunus persica L.)-"Filina", "Gergana", "Ufo-4", "July lady", "Laskava", "Flat Queen", "Evmolpiya", and "Morsiani 90"-growing in Bulgaria were analyzed for the first time. Gas chromatography-mass spectrometry (GC-MS) analysis and the HS-SPME technique revealed the presence of 65 volatile compounds; the main identified components were aldehydes, esters, and fatty acids. According to the provided principal component analysis (PCA) and hierarchical cluster analysis (HCA), the relative quantities of the identified volatile compounds depended on the studied peach variety. The results obtained could be successfully applied for the metabolic chemotaxonomy of peaches.
ABSTRACT
The compounds in volatile flavor substances in duck meats of three different body parts (breast, leg, and wing) were extracted by headspace solid-phase micro-extraction and determined by gas chromatography-mass spectrometry. A total of 16 main volatile compounds including 4 hydrocarbons, 4 alcohols, 2 acids, 3 aldehydes, and 3 others (N-containing, S-containing) were identified in raw duck meats from three different body parts. The hydrocarbon compounds account for more than 50% of all volatile substances in all three body parts. And the percentage of hydrocarbon compounds in raw duck breast meat reaches 82.76%. A total of 81 volatile compounds including 15 hydrocarbons, 10 alcohols, 7 acids, 12 aldehydes, 4 esters, 19 S-containing and N-containing compounds, and 14 others were isolated and identified in 1 hr-marinated and cooked duck meats. A total of 101 kinds of volatile flavor compounds including 13 hydrocarbons, 14 alcohol, 7 acids, 8 aldehydes, 12 esters, 23 S-containing and N-containing compounds, and 24 others were detected in 3 hr-marinated duck meats of the three body parts. It was proved in this study that under the same conditions, the volatile compounds in duck legs are more than those in duck breasts and wings, and the types of volatile flavor substances increase significantly in duck meats after cooked. PRACTICAL APPLICATIONS: Prepared and cooked duck meat, especially wings and legs are popular food in China. The results suggest that Pickling makes duck meat more flavory while proper pickling time is less than 3 hr. Duck wings are better for marinating and cooking compared with duck breasts and legs. The acceptance study of duck meat from different body parts and the analysis of volatile flavor compounds are beneficial for optimizing utilization of whole parts of duck meat.
Subject(s)
Volatile Organic Compounds , Alcohols/analysis , Aldehydes , Animals , Ducks , Esters , Meat/analysis , Volatile Organic Compounds/chemistryABSTRACT
Peony (Paeonia section Moutan DC.) seed oil is a novel vegetable oil with unique aromatic profile. The objectives of this study were to characterize the volatile compounds with optimized analysis conditions, and to study the effects of oxidation during storage. The Headspace Solid-phase Micro-extraction (HS-SPME) conditions were optimized with factors including extraction fiber, extraction time and temperature, as well as sample amount and desorption time. Then, the aromatic compounds extracted from peony seed oil were determined using the odor activity value (OAV) method coupled with the GC-olfactometry. Results found that the best HS-SPME conditions were DVB/CAR/PDMS fibers with magnetic stirring for 50 min of extraction at 60°C. The optimal sample amount was 4 g with 6 min of desorption. Forty-one volatile components were found, and 19 aromatic components were identified using GC-MS and GC-olfactometry. This is the first study to describe 4,7-dimethylbenzofuran in peony seed oil with a unique aroma of grass, light bitter, and fragrance. The stability of alcohol and terpenoids decreased as accelerated oxidation progresses. This study provides the theoretical basis for the sensory attributes, and shelf-life of peony seeds oil products for industry production and marketing.
Subject(s)
Paeonia , Plant Oils , Seeds , Gas Chromatography-Mass Spectrometry , Oxidation-Reduction , Paeonia/chemistry , Plant Oils/chemistry , Seeds/chemistry , Solid Phase MicroextractionABSTRACT
This study was designed to analyze the volatile organic compounds in the leaves of Ambrosia artemisiifolia L. and Artemisia annua L. from Korea. For extraction of volatile compounds, headspace-solid phase micro extraction (HS-SPME) and simultaneous distillation extraction (SDE) were applied and analyzed by gas chromatography/mass spectrometry (GC/MS). From the results, SDE extraction was found to give the highest concentration of volatile compounds with an average concentration of 1,237.79 mg/kg for A. annua L. leaves compared to 1,122.73 mg/kg by HS-SPME technique. A total of 116 volatile organic compounds were identified, including 76 similar volatile organic compounds detected by both the methods of extraction in leaves of subject species at varying concentrations. Among these 33 volatile organic compounds were reported for the first time from the subject plant species. Thus the present research findings extend the characterization of volatile organic compounds from leaves of A. annua L. and A. artemisiifolia L. species and reported some distinguishing compounds which may be used for their discrimination.
ABSTRACT
Three varieties of safflower seed oil (SSO) from Xinjiang Autonomous Region, China, were analyzed by headspace solid-phase micro-extraction gas chromatography coupled with mass spectrometry (HS-SPME-GC-MS) to reveal volatile components. Overall, 67 volatile components were determined and four compounds including isoamyl alcohol, caproic acid, n-pentanal, and heptanal were newly identified in SSO as aroma-active components. Meanwhile, 16 compounds were selected by relative odor activity value (ROAV) to evaluate contributions of single compounds to the overall odor (ROAV > 1), in which nonanal, (Z)-6-nonenal, and (E)-2,4-decadienal were the top three contributed substances (ROAV > 70). The sensory panel was described as eight definition terms (grassy, fruity, almond, mushroom, fatty, sweet, paddy, and overall fragrance). Principal component analysis (PCA) revealed a significant separation of three cultivars with the first principal component (PC-1) and the second principal component (PC-2) expressing 73.9% and 23.1%, respectively. Both PCA and ROAV allowed identifying the compounds positively correlated to sensory evaluation.
ABSTRACT
Novel Shiraz red wine products enriched with Ganoderma lucidum (GL) extract, a traditional Asian medicinal mushroom, were developed and characterized. GL extract was added at different levels prior to and after primary fermentation to investigate its impact on the juice fermentation kinetics, and the chemical composition and sensory properties of the resulting wines. The fermentation kinetics of red grape juice were not significantly different between ferments. Basic chemical analyses plus headspace solid-phase micro-extraction (HS-SPME), gas chromatographyâmass spectrometry (GC-MS), and a rate-all-that-apply (RATA) (n = 65) sensory panel were used to investigate the influence of GL extract additions on wine composition and sensory characteristics. Of the 54 sensory attributes assessed, 39 significantly differentiated the wines. A clear separation between GL wine treatments was evident with PLS regression, where specific volatiles were correlated with relevant sensory attributes that dominated the wines. These products could be promising for emerging wine markets.
ABSTRACT
This data article describes the analysis of volatile organic compounds (VOCs) in 44 samples of cocoa bean shells (CBS) obtained from cocoa beans of diverse cultivars and collected in different geographical origins. The volatile compounds were extracted by headspace solid-phase microextraction (HS-SPME) method and then analyzed by gas chromatography coupled to a quadrupole mass spectrometry GC-qMS. The retention times, identification and semi-quantification of 101 VOCs are reported. Data collected on the volatile profile of CBS samples using E-nose analysis are also available. Additional data related to physicochemical characteristics and color analysis for CBS samples are reported. Further interpretation and discussion on these datasets can be found in the related article entitled "Assessment of volatile fingerprint by HS-SPME/GC-qMS and E-nose for the classification of cocoa bean shells using chemometrics" (Barbosa-Pereira et al., 2019).
ABSTRACT
Aroma profiles, key aroma compound quantification, and cluster analysis of 15 brands of extra-virgin olive oils (EVOOs) from three countries (Spain, Italy, and Greece) were investigated in the current study. Aroma compounds were isolated from the oil by using solvent-assisted flavor evaporation (SAFE) and solid-phase micro-extraction (SPME) and analyzed by gas chromatography-olfactometry mass spectrometry (GC-MS/O). A total of 89 compounds were screened by SPME/SAFE-GC-MS/O with chromatographic columns in 15 brands of samples. Eighty and 54 compounds were respectively identified by SPME- and SAFE-GC-MS/O. Of those, 44 compounds were detected by both methods. Undecanol, (Z)-4-decenal, (E)-2-dodecenal, and 2-nonanone extracted by SAFE were not found in EVOOs before. Eight classes of aroma compounds were identified, including 17 alcohols, 22 aldehydes, 9 ketones, 4 acids, 14 esters, 5 aromatics, 12 alkene, and 6 others. Eleven compounds were identified as the key aroma compounds in alternative brands of EVOOs by SAFE-aroma extract dilution analysis (AEDA). Hexanal, (E)-2-hexenal, (E)-3-hexenol, acetic acid, and (E)-2-heptenal were the common key aroma compounds by AEDA and odor activity values (OAVs). From the cluster analysis of the heatmap, the aroma compounds of all the Spain EVOOs were similar, and there were some differences from the samples of Italy and Greece. It suggested that both the amount and concentration of aroma compounds determine the similarity of aroma in EVOOs.
Subject(s)
Olive Oil/analysis , Volatile Organic Compounds/analysis , Gas Chromatography-Mass Spectrometry/methods , Olfactometry/methods , Solid Phase Microextraction/methods , Volatile Organic Compounds/chemistryABSTRACT
The interactions between flavors (hexyl acetate [HxAc], heptyl acetate [HpAc], linalyl formate [LiFo], linalyl acetate [LiAc], geraniol, linalool, limonene and myrcene) and soy protein isolate (SPI) were investigated, the influence of flavors structure and preheated SPI (PSPI) were determined by using headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME/GC-MS) technology. For HxAc and HpAc, the binding of SPI and the flavors decreased in the order natureâ¯>â¯80⯰Câ¯>â¯90⯰Câ¯>â¯100⯰C PSPI, for LiFo, LiAc, geraniol, and linalool, natureâ¯<â¯80⯰Câ¯<â¯90⯰Câ¯<â¯100⯰C PSPI. For limonene and myrcene, an increase in headspace concentration or "salting out" effect was noticed. The NSPI (nature SPI) and PSPI of 80⯰C showed two class binding sites for HxAc and HpAc. These results serve as a foundation for further investigation into the effect of preheating of SPI on its ability to bind to flavor-inducing compounds.
Subject(s)
Flavoring Agents/chemistry , Hot Temperature , Soybean Proteins/chemistry , Water/chemistry , Protein BindingABSTRACT
PURPOSE: The volatile compounds that contribute to the flavor of pork are unknown. Therefore, the present study aimed to determine the differences in volatile compounds from pork meats of four different pig breeds using headspace solid-phase micro-extraction (HS-SPME)/gas chromatography-mass spectrometry (GC-MS). METHODS: Piglets from four breeds (8/breed) (crossbred Ziwuling Sus scrofa [SUS] and purebreds Bamei pig [BAM], American Yorkshire pig [YOK], and Hezuo pig [HZP]) were selected. Characteristics of meat were measured. HS-SPME/GC-MS were used to analyze the volatile compounds of the meats. RESULTS: The tenderness, taste, succulence, and broth flavor of the BAM and HZP were good. One hundred and eight volatile compounds with known molecular formulas were identified in BAM, 106 in SUS, 98 in YOK, and 98 in HZP. Sixty-four common volatile compounds were found in all four breeds. The highest relative amount of volatile compounds was found in the BAM. The compounds which may contribute to the flavor of pork were 3-methyl-1-butanol, 1-nonanal, octanal, hexanal, 2-pentyl-furan, 1-penten-3-one, N-morpholinomethyl-isopropyl-sulfide, methyl butyrate, and (E,E)-2, 4-decadienal. CONCLUSION: The volatile compounds in pork belong to several classes, and the highest relative amount of volatile compounds was found in BAM.
ABSTRACT
This paper focuses on several methodological aspects in the quantitation of volatiles in solid samples by headspace solid phase micro-extraction (HS-SPME) combined with gas chromatography and parallel detection by flame ionization detector and mass spectrometry (GC-FID/MS). Informative volatiles, including key odorants and process markers, from single-origin cocoa samples (Colombia, Ecuador, Mexico, Sao Tomè, and Venezuela) were captured at two processing stages along the chocolate production chain (nibs and cocoa mass). Accurate quantitation was achieved by multiple headspace extraction (MHE) in headspace linearity conditions and by external calibration. Quantitative results on selected analytes (3-hydroxy-2-butanone, 2-heptanol, 2,3,5-trimethylpyrazine, 2-ethyl-3,6-dimethylpyrazine, ethyl octanoate, benzaldehyde, 2-methylpropionic acid, 3-methylbutyric acid, ethyl phenylacetate, 2-phenylethyl acetate, guaiacol, 2-phenylethanol, and (E)-2-phenyl-2-butenal) provided reliable information about the key sensory notes of cocoa intermediates (odor activity values) and their origin specificities. Additional information about analytes release by the solid environment (cocoa nibs, mass, and powders) was achieved by modeling decay curves. Parallel detection by MS and FID enabled quantitative cross-validation, and FID-predicted relative response factors (RRFs) extended method quantitation capabilities to additional compounds that were not subjected to an external calibration procedure: 3-methylbutyl acetate (isoamyl acetate), 2-heptanone, heptanal, 2-nonanone, γ-butyrolactone, octanoic acid, 2-ethyl-5(6)-methylpyrazine, phenylacetic acid, phenol, 2-acetyl pyrrole, and 2,3-dihydro-3,5-dihydroxy-6-methyl(4H)-pyran-4-one. This procedure extends method capabilities and information potential with great consistency.
Subject(s)
Chocolate/analysis , Odorants/analysis , Solid Phase Microextraction/methods , Flame Ionization , VolatilizationABSTRACT
Non-targeted metabolomic analyses employing nuclear magnetic resonance- and gas chromatography/mass spectrometry-based techniques were applied for an in-depth characterization of cabbage vinegar, an original agricultural product made from cabbage harvested in Tsumagoi, Japan. Water-soluble and volatile metabolite profiles of cabbage vinegar were compared with those of various vinegars: rice vinegar, grain vinegar, apple vinegar, and black vinegar (Japanese kurozu made of brown rice). Principal component analysis (PCA) of the water-soluble metabolites indicated that cabbage vinegars belonged to an isolated class by the contributions of fructose, pyroglutamic acid, choline, and methiin (S-methylcysteine sulfoxide). Regarding the volatile compounds, the PCA data represented that rice, black, and apple vinegars were characterized by most of the dominant volatiles, such as acetate esters, alcohols, ketones, and acids. Cabbage and grain vinegars were included in the same class although these two vinegars have different flavors. Orthogonal partial least squares-discrimination analysis exhibited the differences in volatile compound profile between cabbage and grain vinegars, revealing that cabbage vinegars were characterized by the presence of sulfides (dimethyl sulfide, dimethyl disulfide, and dimethyl trisulfide), nitriles (allyl cyanide and 4-methylthio-butanenitrile), 3-hexene-1-ol, and crotonic acid. The time-course changes in these highlighted compounds during the acetic acid fermentation of cabbage vinegar suggested that pyroglutamic and crotonic acids were produced through fermentation, whereas choline, methiin, sulfides, nitriles, and 3-hexene-1-ol were derived from cabbage, suggesting the key role of these compounds in the unique taste and flavor of cabbage vinegar.
Subject(s)
Acetic Acid/metabolism , Brassica/metabolism , Gas Chromatography-Mass Spectrometry , Magnetic Resonance Spectroscopy , Metabolomics/methods , Acetic Acid/analysis , Alcohols/analysis , Alcohols/metabolism , Brassica/chemistry , Esters/analysis , Esters/metabolism , Fermentation , Flavoring Agents/analysis , Flavoring Agents/chemistry , Flavoring Agents/metabolism , Ketones/analysis , Ketones/metabolism , Principal Component Analysis , Water/chemistryABSTRACT
The chemical and morphological characteristics of materials released under chemical and physical stress by different rubber granulates used as infill materials in synthetic turf (recycled scrap tires, natural rubber, and a new-generation thermoplastic elastomer) were compared.The headspace solid-phase micro-extraction GC-MS analysis evidenced that at 70 °C natural rubber and thermoplastic elastomer release amounts of organic species much higher than recycled scrap tires. In particular, the desorption of mineral oils, with a prevalence of toxicologically relevant low-viscosity alkanes in the range C17-C22, and plasticizers (diisobutyl phthalate) was clearly evidenced. The new-generation thermoplastic elastomer material also releases butylated hydroxytoluene.In slightly acidic conditions, quite high amounts of bio-accessible Zn, Cu, and Co are released from recycled scrap tires, while natural rubber releases mainly Se and Tl. In contrast, the thermoplastic elastomer does not contain significant concentrations of leachable heavy metals.The formation of small particles, also in the inhalable fraction, was evidenced by electron microscopy after mechanical or thermal treatment of natural rubber.
Subject(s)
Environmental Pollutants/analysis , Metals, Heavy/analysis , Organic Chemicals/analysis , Rubber/chemistry , Elastomers , Gas Chromatography-Mass Spectrometry , Particulate Matter/analysis , Recycling , Solid Phase MicroextractionABSTRACT
Objective: To analyze the volatile components in different brands of moxa cones and sticks. Methods: Head- space solid-phase microextraction coupled with gas chromatography-mass spectrometry(HS-SPME-GC-MS)was used to qualitatively analyze volatile components in different brands of moxa cones and sticks. The relative content of each component was calculated by peak area normalization method. The experimental data were comprehensively evaluated by principal component analysis. Results: The total ion chromatograms of the volatile components of moxa cones and sticks in 7 batches produced by 5 manufacturers were simi- lar on the whole,but the volatile components were still different. Eighty-six compounds were identified initially. The most common components were found to be eucalyptol,camphor,terpineol,bornyl acetate,caryophyllene,caryophyllene,oxide(-)-4-terpineol, and cliff ketone. Conclusion: Using HS-SPME-GC-MS could quickly provide information for the chemical composition of the volatile componentsin themoxaconesandsticks,andtherearesignificantdifferencesin thevolatilecomponentsamongdifferentbrands.
ABSTRACT
A headspace solid-phase micro extraction (HS-SPME) and gas chromatography-tandem mass spectrometric (GC-MS/MS) method is described to detect hydrazine after derivatization with 1,1,1-trifluoro-2,4-pentanedione (1,1,1-TFPD) to 3-methyl-5-(trifluoromethyl) pyrazole in industrial waste water. The following optimal HS-SPME conditions were used: 85 µm-carboxen-polydimethylsiloxane fibre, 100 mg L-1 TFPD, saturated NaCl, an extraction/derivatization temperature of 80 °C, a heating time of 40 min, and a pH of 9.5. Under the established conditions, the detection and quantification limits were 0.002 µg L-1 and 0.007 µg L-1 by using 5 mL of waste water and the intra- and inter-day relative standard deviations were less than 10.2% at concentrations of 0.02 and 0.1 µg L-1. The calibration curve showed good linearity, with r2 = 0.998; the accuracy was in the range of 98.0-103%; and the precision of the assay was less than 10.2% in industrial waste water. Hydrazine was detected over a concentration range of 0.011-0.074 µg L-1 in 5 of 20 waste water samples.