[Simultaneous determination of 10 quaternary ammonium salt bactericides in oral care products by high performance liquid chromatography-evaporative light-scattering detection].

Quaternary ammonium salt bactericides are broad-spectrum bactericides often used in oral care products because of their high antibacterial efficacy, strong penetration, and low toxicity. However, the excessive use of quaternary ammonium salt bactericides may cause contact dermatitis, scalding poisoning, and even death. Existing methods to determine quaternary ammonium salt bactericides are unable to meet current requirements owing to the lack of determination components. Therefore, establishing a simple and accurate method for the simultaneous detection of more quaternary ammonium salt bactericides is necessary. In this study, a method that couples sample pretreatment with high performance liquid chromatography-evaporative light-scattering detection (HPLC-ELSD) was developed for the simultaneous determination of quaternary ammonium salt bactericides in oral care products, including dodecyltrimethylammonium chloride, dodecyldimethylbenzylammonium chloride, benzethonium chloride, tetradecyl trimethyl ammonium chloride, tetradecyldimethylbenzylammonium chloride, N-hexadecyltrimethylammonium chloride, benzyldimethylhexadecylammonium chloride, trimethylstearylammonium chloride, stearyldimethylbenzylammonium chloride, and docosyltrimethylammonium chloride. Some of these bactericides do not absorb ultraviolet light, so a universal evaporative light-scattering detector was used owing to testing cost and stability concerns. The paste samples contained thickening agents, which are highly soluble in water but insoluble in organic solvents; these agents can seriously affect the results of sample pretreatment and damage the chromatographic column. Hence, sample dehydration was necessary. In this study, four dehydration methods were compared. Anhydrous sodium sulfate (Na2SO4) was selected, and the amount of Na2SO4 was optimized. Based on the solubility of the 10 target compounds and extraction efficiency, three extraction solvents were compared, and ethanol was selected. Ultrasonic extraction was the primary extraction process used in this study. The effects of different ultrasonication times, temperatures, and powers on the extraction recoveries were also investigated. Ultimately, the optimized conditions were as follows: extraction of the dehydrated paste and powder samples using ethanol at room temperature (25 ℃) for 20 min under 100 W ultrasound power, and dilution of the liquid sample with ethanol. After extraction, the samples were separated on an Acclaim Surfactant column (150 mm×4.6 mm, 5 µm) with 50 mmol/L ammonium acetate aqueous solution (pH=5.5) (A) and acetonitrile (B) as mobile phases. The gradient elution program were as follows: 0-5.0 min, 75%A-35%A, 5.0-15.0 min, 35%A-20%A, 15.0-20.0 min, 20%A, 20.0-21.0 min, 20%A-75%A, 21.0-25.0 min, 75%A. An external standard method was used for quantitative determination. The 10 compounds were analyzed within 25 min. Linear equations, correlation coefficients, and linear ranges were obtained by analyzing a series of mixed standard working solutions. The limits of detection (LODs, S/N=3) and quantification (LOQs, S/N=10) of the 10 components were determined. Stearyldimethylbenzylammonium chloride and docosyltrimethylammonium chloride showed good linear relationships in the range of 10-200 mg/L, while the other compounds demonstrated good linear relationships in the range of 5-100 mg/L. In all cases, correlation coefficients (R2) of no less than 0.9992 were obtained. The LODs and LOQs were in the range of 1.42-3.31 mg/L and 4.25-9.94 mg/L, respectively. Ten analytes were spiked in blank matrices, such as toothpaste (paste), mouthwash (liquid), and dentifrice powder (powder) at three levels, and the recoveries and precisions were calculated. The average recoveries were 87.9%-103.1%, and the corresponding relative standard deviations (RSDs) did not exceed 5.5% (n=6). The developed method was used to detect 109 oral care products. Benzyldimethylhexadecylammonium chloride and stearyldimethylbenzylammonium chloride revealed high detection rates. Moreover, the amount of stearyldimethylbenzylammonium chloride in one toothpaste sample exceeded regulatory requirements. Given its advantages of good precision and accuracy, the developed method is suitable for the quantitative analysis of the 10 aforementioned compounds in typical oral care products. The study findings can serve as a reference for the quality and safety monitoring of oral care products.

[Determination of adsorbable organic halogens in textiles by ultrasonic extraction-high temperature combustion absorption-ion chromatography].

Adsorbable organic halogens (AOX) are often introduced or produced in textile and dyeing processes, such as the chlorination shrink proof process of wool, the bleaching process by sodium hypochlorite and chlorite, the dry-cleaning process by chlorinated solvent, etc. However, part of AOX is difficult to biodegrade and is a persistent bioaccumulative toxic substance with high fat solubility. To promote clean production of textiles and to protect the health of consumers, a conventional method for the detection of AOX in textiles must be established urgently. In this study, a new method was developed for the determination of AOX in textiles by ultrasonic extraction-high temperature combustion absorption-ion chromatography (IC). In this method, AOX in textiles were extracted by ultrasonic extraction at room temperature with ultra-pure water as solvent. Activated carbon was added to the extraction solution for oscillatory adsorption and removal of inorganic halides with acidic sodium nitrate solution. The AOX adsorbed on activated carbon were cracked, burned, and gasified by the oxidative combustion method with a programmed heating mode. The product hydrogen halide gas entered the absorption solution with the carrier gas, followed by separation and determination by IC with external standard method of quantification. During the experiment, the pretreatment conditions were optimized, including the extraction time of AOX, the amount of activated carbon, the combustion gas and its flow rate, the temperature program for high-temperature oxidation combustion, the absorption method, and the absorption solution. The instrument conditions of ion chromatography, including the chromatographic column, column temperature, eluent, and its flow rate, were also optimized. The results showed that the method was linear in the range of 0.02-10 mg/L for the standard solutions of fluorine, chlorine, bromine, and iodine ions, and the correlation coefficients (R2) were greater than 0.999. The limits of quantification of the method for AOX were 0.10-0.50 mg/kg. The negative textile samples of cotton, wool, and polyester were used as the sample matrix, and typical organic halogens were selected for standard addition and recovery. At low, medium, and high spiked levels, the average recoveries of AOX in cotton, wool, and polyester fiber were 82.3%-98.7%. The corresponding relative standard deviations (RSDs, n=7) were 2.0%-5.7%, indicating that the method had good recovery and precision. This method was used to determine actual textile samples, and AOX at different contents were detected in blue coated polyester fabric and black modal fabric with good repeatability. The established method improved the recoveries of AOX converted into inorganic halogens via oscillating adsorption of activated carbon, high-temperature oxidation combustion with a programmed heating mode, and secondary absorption using a porous absorption bottle. Meanwhile, the separation and detection of halogen ions was successfully conducted using the ion chromatography instrument with good selectivity and high sensitivity, without any interference of impurity ions. The method is simple, accurate, and reliable, and fully meets the limit requirements of domestic and foreign regulations and textile standards; the method is also suitable for the detection and analysis of AOX in textiles.

[Simultaneous determination of 18 chlorinated hydrocarbon organic solvents in cosmetics by gas chromatography-mass spectrometry].

Organic solvents can be used to dissolve and disperse flavors, bactericides, preservatives, surfactants, oils, and coloring agents during the production of cosmetics. However, harmful chlorinated hydrocarbon organic solvents are found in cosmetics such as manicure products, anti-acne products, and perfumes. Long-term contact with such cosmetics will have an adverse effect on the consumers' health. Past research has focused on very few chlorinated hydrocarbon organic solvents in cosmetics. Most organic solvents with low boiling points are typically determined by headspace-gas chromatography-mass spectrometry. In this study, a high-boiling-point solvent was used as the injection solvent, and the solvent delay time was cancelled. The compounds that could only peak during the solvent delay time were effectively separated. A method coupling sample pretreatment with gas chromatography-mass spectrometry (GC-MS) was developed for the simultaneous determination of 18 chlorinated hydrocarbon organic solvents in cosmetics: vinylidene chloride, dichloromethane, trans-1,2-dichloroethylene, 1,1-dichloroethane, cis-1,2-dichloroethylene, chloroform, 1,1,1-trichloroethane, carbon tetrachloride, 1,2-dichloroethane, trichloroethylene, 1,1,2-trichloroethane, tetrachloroethylene, 1,1,1,2-tetrachloroethane, 1,1,2,2-tetrachloroethane, 1,2,3-trichloropropane, pentachloroethane, hexachloroethane, and hexachloro-1,3-butadiene. These 18 solvents have a wide range of polarities and a notable difference in volatilities, in addition to many isomers and structural analogs, which renders their separation difficult. Therefore, the separation effect of three kinds of GC columns with different polarities was compared. n-Tetradecane, an injection solvent with good solubility, was selected as the extraction solvent. An organic solvent with high polarity has low extraction rate because of its weak polarity. Adding sodium chloride solution to the sample to induce the "salting out" effect could change the partition coefficient of the components, thereby improving the extraction rate. Therefore, the concentration of the sodium chloride solution added to the sample was optimized. In this work, liquid-liquid extraction was the main extraction process, so the effects of different shaking times, temperatures, and frequencies on the extraction rate were discussed. The optimized results are as follows: at normal temperature, the sample dispersed or dissolved in saturated sodium chloride solution was extracted by n-tetradecane at an oscillating speed of 100 r/min for 20 min. Separation was performed on an Agilent J&W DB-624 column (30 m×0.25 mm×1.4 µm) by GC-MS with an electrospray ionization (EI) source in the selected ion monitoring (SIM) mode. The external standard method was used for quantitative determination. The 18 compounds could be analyzed within 19 min. The linear equations, linear correlation coefficients, and linear ranges were obtained by analyzing a series of mixed standard working solutions. The limits of detection (LODs, S/N=3) and limits of quantification (LOQs, S/N=10) of the 18 components were determined. The negative lipstick (solid) and mouthwash (liquid) samples were used as the spiked sample matrix at three levels, and the recoveries and precisions were calculated. The calibration curves showed good linearities for the 18 chlorinated hydrocarbon organic solvents in range of 0.2-100 mg/L, with correlation coefficients (R2) not less than 0.9992. The LODs and LOQs were in the range of 0.033-0.049 mg/L and 0.10-0.15 mg/L, respectively. The average recoveries of the 18 chlorinated hydrocarbon organic solvents in lipstick (solid) and mouthwash (liquid) were 92.4%-103.1% and 93.3%-102.4% respectively; the corresponding relative standard deviations (RSDs) were 3.1%-5.3% and 2.8%-5.4% (n=6). This method was used to determine 115 different types of cosmetics, and tetrachloroethylene was detected in three nail polishes. With its advantages of high sensitivity, good precision, and accuracy, the developed method is suitable for the quantitative analysis of the aforesaid 18 compounds in all kinds of cosmetics. The study findings would serve as a reference for the quality and safety monitoring of cosmetics.

Folated pH-degradable nanogels for the simultaneous delivery of docetaxel and an IDO1-inhibitor in enhancing cancer chemo-immunotherapy.

Combining chemotherapy and immunotherapy has been considered as an attractive approach to improve cancer therapy. Here we prepared folated PVA-based nanogels for the simultaneous delivery of docetaxel (DTX) and the indoleamine 2,3-dioxygenase 1 (IDO1) inhibitor NLG919 (N9) for enhancing cancer chemo-immunotherapy. FDA-approved poly(vinyl alcohol) (PVA) with good biocompatibility was modified with vinyl ether acrylate (VEA) groups for UV-crosslinking and acidic degradation. Carboxyl groups were introduced via modification with succinic anhydride for improved drug loading and folic acid (FA) ligands were incorporated for tumor targeting. UV-crosslinked folated PVA nanogels were efficiently taken up by tumor cells followed by endo/lysosomal pH-triggered intracellular drug release, which induced significant cytotoxicity towards 4T1 breast cancer cells in vitro. DTX and N9 co-loaded PVA nanogels exhibited a much higher antitumor efficiency in 4T1 mouse breast cancer models in vivo as compared to the free drug controls. The drug-laden nanogels not only directly killed the tumor cells by DTX, but also induced immunogenic cell death (ICD) promoting intratumoral accumulation of cytotoxic T lymphocytes, and further combining with N9 elevated the intratumoral infiltration of CD8+ T cells and NK cells and inhibited the infiltration of MDSCs, downregulating IDO1-mediated immunosuppression.

[Simultaneous determination of 18 fluorescent whitening agents in textiles by ultra performance liquid chromatography].

A method was developed for the simultaneous determination of 18 fluorescent white-ning agents (FWAs) in textiles by ultra performance liquid chromatography with fluorescence detection (UPLC-FLR). The sample was extracted with chloroform-ethanol (6:4, v/v). The separation was performed on an ACQUITY UPLC HSS T3 column (100 mm×2.1 mm, 1.8 µm) with gradient elution. Methanol-water (containing 5 mmol/L ammonium acetate) was used as the mobile phase with a flow rate of 0.4 mL/min. The fluorescence detector was used at 350 nm excitation wavelength and 430 nm emission wavelength. External standard method was used for the quantitative determination. The calibration curves showed good linearity in respective ranges for the 18 FWAs with correlation coefficients (R2) no less than 0.9992. The limits of quantifications (LOQs, S/N=10) were in the range of 0.002-0.1 mg/L. The average recoveries of the 18 FWAs ranged from 88.3% to 104.5% at the different spiked levels with the relative standard deviations (RSDs) of 2.0%-5.5% (n=6). The method has high sensitivity, good precision and accuracy, and is applicable to the determination of all kinds of textiles.

[Rapid detection of eight fluorescent whitening agents in textile by ultra performance convergence chromatography].

An accurate quantitative and confirmative method has been developed for the deter- mination of eight fluorescent whitening agents (FWAs) in textile by ultra performance conver- gence chromatography (UPC2) coupled with photo diode array (PDA) detection, including 1,2-bis (5-methyl-2-benzoxazole) ethylene (PF), 7-diethylamino-4-methylcoumarin (SWN), 2, 2'-(2,5-thiophenediyl) bis(5-(1,1-dimethylethyl)-benzoxazol (OB), 2-[4-[2-[4-(2-benzox- azolyl) phenyl] ethenyl] phenyl] -5-methyl-benzoxazol (KSN), 1,4-bis (2-cyanostyryl) benzene (ER-I), 1-(2-cyanostyryl)-4-(4-cyanostyryl) benzene (ER-II), 2,2'-(1,4-naphthalenediyl) bis-benzoxazol (KCB), 4,4'-bis[2-(2-methoxyphenyl) ethenyl]-1,1'-biphenyl (FP). The sample was extracted with xylene and concentrated by a rotary evaporator, and then qualitatively and quantitatively analyzed by UPC2. The separation of target compounds was achieved on an ACQUITY UPC2 HSS C18 SB column (100 mm x 3.0 mm, 1.8 µm) by a gradient elution with supercritical carbon dioxide and methanol as mobile phases. External standard method was used for the quantitative determination and the calibration curves showed good linearity in the concentration range of 1.0-20.0 mg/L for the eight target compounds with correlation coefficients not less than 0.999 1. The limits of quantification of the eight compounds (LOQs, S/N = 10) were 0.70-0.95 mg/L. The average recoveries of the eight compounds ranged from 90.9% to 96.5% at the spiked levels of 2.0, 5.0, 10.0 mg/kg with the relative standard deviations (RSDs) of 2.8%-4.2%. The method is simple, accurate and time-saving with high sensitivity, and can be used for the rapid determination of the eight FWAs in textile.

[Determination of distearyl dimethyl ammonium chloride in textiles by reversed-phase and normal-phase liquid chromatography-electrospray ionization tandem mass spectrometry].

A method of reversed-phase (RP)/normal-phase (NP)-liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) was developed for the determination of distearyl dimethyl ammonium chloride (DSDMAC) in textiles. The DSDMAC in textile was extracted by ultrasound-assisted extraction using methanol as extraction solvent under the conditions of 70 degrees C and 420 W within 30 min. The three quaternary ammonium compounds of DSDMAC were detected by LC-MS/MS in the selective reaction monitoring (SRM) mode. The limits of detection (LODs) (S/N = 3) of DSDMAC detected by RPLC-MS/MS and NPLC-MS/MS based on an amino-column were 0.1 mg/kg and 0.01 mg/kg, respectively. The recoveries of DSDMAC spiked in the eight different types of blank fabrics ranged from 85.5% to 103% with the relative standard deviations (RSDs) of 4.18% - 12.8% (n = 5) by RPLC-MS/MS method. Five laboratories were invited to take part in the validation of the method, and the RSDs of inter-lab were 7.3% - 9.4% on two reference samples. The method is fast, accurate and reproducible, and can meet the demands of the determination of DSDMAC in textiles.

Photodegradation of crystal violet in TiO(2) suspensions using UV-vis irradiation from two microwave-powered electrodeless discharge lamps (EDL(-2)): products, mechanism and feasibility.

Aqueous crystal violet (CV) solutions containing P25-TiO(2) photocatalyst were irradiated with ultraviolet-visible (UV-vis) light from two microwave-powered electrodeless discharge lamps (EDL(-2)). The results demonstrated that approximately 94.4% of CV was effectively removed after 3 min of irradiation, with a pseudo-first order kinetic constant of 0.838 min(-1). According to 32 kinds of products, a five-step degradation pathway of CV was proposed. Further investigations showed that (1) three kinds of N-demethylated products and 4-dimethylaminobenzophenone (DLBP) were the main intermediates; (2) malachite green (MG) and leuco-crystal violet could not be generated by N-demethylation and phototransformation reactions, respectively; (3) bis(4-(dimethylamino)phenyl)methanone preferentially generated via decomposition of the conjugated structure of CV could be further N-demethylated into DLBP. Moreover, the unique degradation pathways of CV and MG were ascribed to the different substituents on the conjugated structures. Additionally, the cost and kinetic constant of different processes was also evaluated, and the results indicated the feasibility of this method for treatment of CV in field situations.

Simultaneous identification of nine carcinogenic dyes from textiles by liquid chromatography/electrospray ionization mass spectrometry via negative/positive ion switching mode.

A method has been established by using liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI/MS/MS) for simultaneous separation and identification of nine carcinogenic dyes (Acid Red 26, Direct Blue 6, Direct Black 38, Direct Red 28, Basic Red 9, Basic Violet 14, Disperse Blue 1, Disperse Orange 11 and Disperse Yellow 3) prohibited in textile materials under EU 2002/371/EC decision. Three selected reaction monitoring (SRM) transitions and negative/positive ion switching mode in one single analysis was applied to differentiate between the dyes of different classes. A lower limit of detection was achieved at 0.025-0.25 mg kg(-1) of positive ESI dyes and 0.005-0.025 mg kg(-1) of negative ESI dyes. The accurate and sensitive identification of the nine dissimilar analytes was achieved by combining the characterized ions and retention time of the standards, for example, the characterized ions of [M - xNa](x-), [M -Cl](+) and [M + H](+), respectively were detected for the the sulfonated (acid and direct), basic and disperse dyes. The chromophore groups of azo, triphenylmethane and anthraquinone in precursor ions were found to have fragmented in SRM mode. These results demonstrated a sensitive, accurate and rapid identification.

Quantitative determination of 16 polycyclic aromatic hydrocarbons in soil samples using solid-phase microextraction.

A method for the determination of polycyclic aromatic hydrocarbons (PAHs) in soil samples using ultrasonic-assisted extraction with internal surrogates combined with solid-phase microextraction and GC-MS has been developed. Five kinds of commercial solid-phase microextraction fibers, 100 microm PDMS, 30 microm PDMS, 65 microm PDMS/DVB, 50 microm DVB/CAR/PDMS and 85 microm PA, were compared to choose the optimal SPME fiber for extraction of PAHs. One hundred micrometers of PDMS fiber was found to be more suitable for the determination of PAHs due to its wider linear range, better repeatability, lower detection and more satisfactory efficacy than the other fibers. Under the recommended conditions, 100 microm PDMS fiber could provide low nanogram level detection limits with correlation coefficient greater than 0.98. The method was also applied to determine PAHs in a spiked soil sample, obtaining recoveries higher than 79.3%. A field study with naturally contaminated samples from local contaminated sites was carried out. The proposed method was found to be a reliable, inexpensive and simple preparation method for quantitative determination of 16 PAHs in soil samples.

Microwave-enhanced H2O2-based process for treating aqueous malachite green solutions: intermediates and degradation mechanism.

This work was originally performed to compare H(2)O(2)-based degradation of aqueous malachite green (MG) under microwave (MW)-enhanced and conventional heating (CH)-enhanced conditions, with the whole reaction courses traced by UV-vis spectrophotometer. The results showed that the higher discoloration rates of MG were available during MW-enhanced process, implying that the special heating way of MW might be more benefit for the generation of hydroxyl radicals than that of CH. Furthermore, major intermediates were separated and identified by HPLC-ESI-MS and GC-MS techniques. On the basis of 53 intermediates, degradation mechanism was deduced as follows: firstly, N-de-methylation reactions. Secondly, adduction reactions. Thirdly, decomposition of conjugated structure reactions of MG. Fourthly, removal of benzene reactions. Finally, open-ring reactions. Additionally, results revealed that microwave-enhanced H(2)O(2)-based treatment had more advantages, such as higher degradation efficiency, and no removal of catalyst after treatment.

Photocatalytic degradation of rhodamine B by Bi(2)WO(6) with electron accepting agent under microwave irradiation: mechanism and pathway.

Bi(2)WO(6) was successfully synthesized by a facile hydrothermal method, and characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and BET. As a result, Bi(2)WO(6) crystals displayed mainly square-plate-like morphologies with a short edge and the average crystalline size was in the range of 50-150 nm. Then microwave-assisted photocatalytic degradation of rhodamine B (RhB) using Bi(2)WO(6) was investigated. The results illustrated that RhB (10 mg/L) was bleached effectively and the removal efficiency was about 94% in 60 min. Effect of electron accepting agent (air, H(2)O(2)) on the degradation efficiency of RhB was also examined. Degradation intermediates of RhB in the presence of H(2)O(2) were identified by LC/MS/MS and GC/MS. All five N-de-ethylated intermediates were monitored by LC/MS/MS easily, and seven organic acids such as succinic acid, benzoic acid, adipic acid, 3-hydroxybenzoic acid, phthalic acid, etc., were also detected by GC/MS. The possible degradation mechanism of RhB in the presence of H(2)O(2) included four processes: N-de-ethylation, chromophore cleavage, opening-ring and mineralization, which coexisted in microwave-assisted photocatalytic system.

Microwave-assisted rapid photocatalytic degradation of malachite green in TiO2 suspensions: mechanism and pathways.

Microwave-assisted photocatalytic (MPC) degradation of malachite green (MG) in aqueous TiO2 suspensions was investigated. A 20 mg/L sample of MG was rapidly and completely decomposed in 3 min with the corresponding TOC removal efficiency of about 85%. To gain insight into the degradation mechanism, both GC-MS and LC-ESI-MS/MS techniques were employed to identify the major intermediates of MG degradation, including N-demethylation intermediates [(p-dimethylaminophenyl)(p-methylaminophenyl)phenylmethylium (DM-PM), (p-methylaminophenyl)(p-methylaminophenyl)phenylmethylium (MM-PM), (p-methylaminophenyl)(p-aminophenyl)phenylmethylium (M-PM)]; a decomposition compound of the conjugated structure (4-dimethylaminobenzophenone (DLBP)); products resulting from the adduct reaction of hydroxyl radical; products of benzene removal; and other open-ring intermediates such as phenol, terephthalic acid, adipic acid, benzoic acid, etc. The possible degradation mechanism of MG included five processes: the N-demethylation process, adduct products of the hydroxyl radical, the breakdown of chromophores such as destruction of the conjugated structure intermediate, removal of benzene, and an open-ring reaction. To the best of our knowledge, it is the first time the whole MG photodegradation processes have been reported.

[Fast separation and identification of nine carcinogenic dyes in textiles using liquid chromatography-electrospray tandem mass spectrometry].

A qualitative method of the identification of nine carcinogenic dyes prohibited in textiles was developed using high performance liquid chromatography-tandem mass spectrometry interfaced with electro-spray ionization (HPLC-ESI-MS/MS) in the selective reaction monitoring (SRM) mode. The dyes were extracted from textiles composed of natural or chemical fibers by methanol under ultrasounication, and then eluted with gradient by acetonitrile and 5 mmol/L ammonium acetate from an RP-C18 column with two segments in effluents. The first effluents accommodated Acid Red 26, Direct Blue 6, Direct Black 38 and Direct Red 28 with negative ionization mode, while the second accommodated Basic Red 9, Basic Violet 14, Disperse Blue 1, Disperse Orange 11 and Disperse Yellow 3 with positive ionization mode. Thus the investigated compounds could be identified simultaneously with single-run analysis no matter which type of the fibre the sample was and no matter which category of the dye the analyte was. The established method was successfully applied to identify the carcinogenic dyes in textile samples through comparing the chromatographic retention time and the relative abundance of characteristic product ions with the standards.