API Source Research Articles

Analysis of Vulnerabilities in College Web-Based System

Web-based systems are used extensively in Korea because web standards have been adapted by the law (e.g., Electronic Government Act). Users can easily access web-based systems if they are connected to the Internet. However, distinguishing between malicious and benign access is very difficult and many potential vulnerabilities exist. In this study, we attempt to leak the information of other users without permission using a non-encrypted API and web source code analysis in a college web-based system. An experiment demonstrates that the information (e.g., other students’ course grades) can be leaked and abnormal data can be embedded in the request. In addition, we discuss methods for preventing such vulnerability attacks.

Fitting missing API puzzles with machine translation techniques

While implementing software projects, developers do not reinvent the wheel but try to reuse existing API calls and source code. In recent years, the problems related to recommending APIs and code snippets have been intensively investigated. Although current approaches have achieved encouraging performance, there is still the need to improve the recommendation process’s effectiveness and efficiency. In this work, we reformulate the problem of API recommendations by proposing learning and recommending API sequences relevant to a given coding context. We present LUPE, a novel approach to API and code recommendation, exploiting cutting-edge deep learning techniques. Thanks to the underlying Encoder–Decoder architecture specialized in transforming sequences, LUPE can effectively learn the order in which invocations occur. The approach has been evaluated on two Android datasets and compared with GAPI and FACER, two state-of-the-art API recommender systems. Being fed with augmented training data, our conceived approach can obtain a high prediction accuracy, and produce a perfect match in several cases, hence outperforming the baselines.

Scientific Irrigation Scheduling by Utilizing Weather Api and Open Source Modeling in Texas High Plains and Rio Grande Basin

Scientific Irrigation Scheduling by Utilizing Weather Api and Open Source Modeling in Texas High Plains and Rio Grande Basin

Real-Time Weather Analytics

Weather forecasting is one of the biggest challenges that modern science is still contending with. The advent of high-power computing, technical advancement of data storage devices, and incumbent reduction in the storage cost have accelerated data collection to turmoil. In this background, many artificial intelligence techniques have been developed and opened interesting window of opportunity in hitherto difficult areas. India is on the cusp of a major technology overhaul with millions of people's data availability who were earlier unconnected with the internet. The country needs to fast forward the innovative use of available data. The proposed model endeavors to forecast temperature, precipitation, and other vital information for usability in the agrarian sector. This project intends to develop a robust weather forecast model that learns automatically from the daily feed of weather data that is input through a third-party API source. The weather feed is sourced from openweathermap, an online service that provides weather data, and is streamed into the forecast model through Kafka components. The LSTM neural network used by the forecast model is designed to continuously learn from predictions and perform actual analysis. The model can be architected to be implemented across very large applications having the capability to process large volumes of streamed or stored data.

Atmospheric pressure ionization for gas chromatography-high resolution mass spectrometry determination of polychlorinated naphthalenes in marine sediments

In this work, the performance of the atmospheric pressure chemical ionization (APCI) and photoionization (APPI) was assessed to develop a new selective and sensitive gas chromatography-high resolution mass spectrometry (GC-HRMS) method for the determination of polychlorinated naphthalenes (PCNs) in sediment samples. The capability of both APCI and APPI sources for the ionization of PCNs was investigated, showing the formation of the molecular ion and the [M‒Cl+O]‒ ion in positive and negative ion modes, respectively. Positive ion APCI provided high responses using high corona ion current, while the use of high vapour pressure dopant-solvents, such as toluene in positive mode and diethyl ether in the negative mode, was required to achieve high ionization efficiencies in APPI. The performance of the two API sources in the PCN determination by GC-HRMS were compared and the best results were achieved using the GC-APPI(+)-HRMS (Orbitrap) system. The GC-APPI(+)-HRMS (Orbitrap) method was applied to the characterization of Halowax mixtures and the analysis of marine sediments collected near to the coastal area of Barcelona (NE, Spain), demonstrating a great detection capability with low method limits of detection (0.2–1.6 pg g−1 dry weight), good precision (RSD <15%) and trueness (relative error <13%). Total PCN concentrations ranged from 0.35 to 5.0 ng g−1 dry weight and the presence of related compounds, such as polychlorinated biphenyls (PCBs), was also detected by combining positive and negative ion modes, providing complementary information to better monitor of all PCN congener groups. The results presented here show the feasibility of the GC-APPI-HRMS method for the suitable determination of PCNs.

Formation of the exceptional [M - H]+ cation in atmospheric pressure ionization mass spectrometry analysis of 2-(diphenylsilyl) cyclopropanecarboxylate esters.

In general, ionization of analytes in atmospheric pressure ionization mass spectrometry (API-MS) in positive ion mode results in the formation of protonated molecules ([M + H]+ ) and/or cationized molecules (e.g., [M + Na]+ ). The formation of specific [M - H]+ cations in the API process is of significant interest for further investigation. The ionization processes of 2-(diphenylsilyl)-1-phenyl-cyclopropanecarboxylate esters were investigated using electrospray ionization (ESI)-MS and atmospheric pressure chemical ionization-MS in positive ion mode. Theoretical calculations were carried out with the Gaussian 03 program using the density functional theory (DFT) method at the B3LYP/6-311 + G(2d,p) level. The anomalous [M - H]+ ion and the regular [M + Na]+ ion were both observed using ESI-MS. Interestingly, no [M + H]+ ion was obtained in the ESI-MS analysis, and acidification of the ESI solvent accelerated the formation of [M - H]+ rather than [M + H]+ ion. DFT calculations for the typical methyl 2-(diphenylsilyl)-1-phenyl-cyclopropanecarboxylate (1) indicated that the [1 + H]+ ion can thermodynamically and kinetically undergo facile H2 elimination to generate [1 - H]+ . The favorable formation of [M - H]+ ions in these compounds is attributed to the unique diphenylhydrosilyl group in their structure. The [M + H]+ ion formed easily underwent H2 elimination to produce the [1 - H]+ ion in the API source, and thus, acidification of the ESI solvent apparently accelerates the formation of the [1 - H]+ ion.

Fragmentation studies of neutral per- and polyfluoroalkyl substances by atmospheric pressure ionization-multiple-stage mass spectrometry.

The establishment of fragmentation pathways has a great interest in the identification of new or unknown related compounds present in complex samples. On that way, tentative fragmentation pathways for the ions generated by atmospheric pressure ionization of neutral per- and polyfluorinated alkyl substances (PFASs) have been proposed in this work. Electrospray (ESI), atmospheric pressure chemical ionization (APCI) and photoionization (APPI) were evaluated using mobile phases and source conditions that enhance the ionization efficiency of ions generated. A hybrid mass spectrometer consisting of a linear ion trap and an Orbitrap was used to combine the information of both multiple-stage mass spectrometry (MSn) and mass accuracy measurements to characterize and establish the genealogical relationship between the product ions observed. The ionization mechanisms to generate ions such as [M-H]-, [M]-•, and [M+O2]-• or the in-source collision-induced dissociation (CID) fragment ions in each API source are discussed in this study. In general, fluorotelomer olefins (FTOs) ionized in negative-ion APCI and APPI generated the molecular ion, while fluorotelomer alcohols (FTOHs) also provided the deprotonated molecule. Besides, fluorooctane sulfonamides (FOSAs) and sulfonamido-ethanols (FOSEs) led to the deprotonated molecule and in-source CID fragment ions, respectively. The fragmentation pathways from these precursor ions mainly involved initial α,β-eliminations of HF units and successive losses of CF2 units coming from the perfluorinated alkyl chain. Moreover, FTOHs and FOSEs showed a high tendency to generate adduct ions under negative-ion ESI and APPI conditions. The fragmentation study of these adduct ions has demonstrated a strong interaction with the attached moiety. Graphical abstract.

Detection of multiclass explosives and related compounds in soil and water by liquid chromatography-dielectric barrier discharge ionization-mass spectrometry.

In this work, the multiclass detection of explosives and related compounds has been studied by liquid chromatography-high-resolution mass spectrometry by means of a time-of-flight mass spectrometer (TOFMS) operated in the negative ion mode, using dielectric barrier discharge ionization (DBDI). Reversed-phase high-performance liquid chromatography (HPLC) separation was performed using water-methanol mobile phase without any modifier, although the effect of ammonium acetate was studied. DBD plasma was generated by applying a square wave voltage of 2.5kV to a 100-mLmin-1 He flow. The DBDI probe was adjusted to fit the commercial API source housing so that the HPLC eluent was nebulized and vaporized in the same manner as for atmospheric-pressure chemical ionization (APCI). The ionization process was affected by the temperature of the two nitrogen streams used to vaporize the solvent and the analytes, particularly for RDX and HMX, which are thermolabile compounds. The best approach in terms of sensitivity for all the studied compounds was the use of a gradient of temperatures in the ionization source, starting at 225/200°C (vaporizer/drying gas temp) for nitramines and ending at 350/325°C for nitroaromatic compounds. High-resolution full-scan spectra of individual selected compounds were recorded by LC-DBDI-TOFMS, and the results were compared to LC-APCI-TOFMS. A better sensitivity (slope of calibration curve) was obtained by DBDI for more than 70% of the studied compounds in both wastewater and soil extracts. Graphical abstract ᅟ.

Development of an LC-Tandem Mass Spectrometry Method for the Separation of Montelukast and its Application to a Pharmacokinetic Study in Humans

Accurate, precise, and sensitive LC-MS/MS assay method for the determination of montelukast (MO) in human plasma samples using gliclazide (GL) as internal standard was developed and applied in pharmacokinetics study.MO extracted by protein precipitation using acetonitrile. Chromatographic separation was carried out using a Agilant Triple quadrupoles mass spectrometer with API source with an Agilant SB- C18 (50×4.6 mm), 1.8 µm particle size column. A mobile phase consisting of acetonitrile: 0.1% formic acid (84:16) was delivered. Calibration curves were linear in the concentration range of (10.00-800.00) ng/ml. The bioanalytical method for determination of MO was successfully applied to assess pharmacokinetics of montelukast. The LLOQ was sensitive enough for detecting terminal phase concentrations of the drug. This study showed that developed method is suitable for MO pharmacokinetic study.

Establishing community models as the underpinning of neuroscience: linking computational and experimental data

In Physics, as in other “hard sciences”, both research and education are built around systems and their associated models that are accepted as fundamental to the field. This is not the case within Neuroscience, although the existence of simulation systems like GENESIS and NEURON are producing an informal propagation of particular models between laboratories. One of the core tenants of the reconfiguration of GENESIS is that fully developed community models will not exist until the process of building, evaluating, and propagating models is incorporated into the structure of the simulation system itself. To be successful, such systems will also have to provide explicit links to experimental data and procedures. GENESIS 3.0 (G-3) conforms to the CBI federated software architecture [1]. It is explicitly constructed around an ideal user workflow [2] that provides an organizing principle for simulator use. The modular nature of the system separates low-level numeric data from high-level biological representations, as well as the data and control functions. This facilitates the interface of different databases to significantly enhance two broad categories of user and developer experience. One is organized around an ideal user workflow while the other supports a multi-level documentation system that informs user and developer concerns. We show how this information infrastructure supports scientific communication through the development of community models that can then integrate computational models and experimental neuroscience. G-3 documentation is organized into seven levels, each served by a single repository: (1-2) Introductory material and user guides, (3-4) Automated use cases and technical guides, (5-7) Algorithm, API and hyperlinked source code documentation. Both within each repository and across the different levels, documents are organized by a user defined tagging system that creates horizontal and vertical reader flows. This simplifies the communication of computational models by separating the technical aspects of a model from its scientific content and interpretation. The dynamic creation of horizontal and vertical reader flows allows to reinterpret the capabilities of this documentation system from the perspective of a model publication workflow. The lowest levels (Levels 5-7) describe purely technical components of model implementation entirely devoid of scientific interpretation. Higher levels communicate the nontechnical scientific narratives generated by both computational and experimental projects. For example, Level 4-3: Explain biological mechanisms obtained by computational studies, community models, and experimental research, Level 2: Integrates results of computational and experimental neuroscience, and Level 1: General introductions and reviews of neuroscience. This results in a communication gradient where increasing detail about any aspect of a publication is accessible from a given level. We show examples of (1) Horizontal workflows, e.g. model lineage, and (2) Vertical workflows, e.g. “drilling down” from the biological concepts of a model to increasingly technical details of model implementation or, vice-versa, starting from technical implementations going up to their uses in models and simulations and their scientific interpretation. These are the first steps in the implementation of a model-based publication system for scientific communication [3]. Here, we present a new view of the G-3 documentation system as a model sharing system that not only incorporates the models and their interpretation, but also their technical and algorithmic implementation and their relationship with the experimental data on which they are based. Employed in this way, the documentation system also enhances G-3 to support the integration and communication of computational and experimental neuroscience. This research was supported by NSF grant HRD-0932339 to the University of Texas at San Antonio. Hugo Cornelis is supported by the CREA Financing program (CREA/07/027) of the K.U.Leuven, Belgium. Hugo Cornelis, Armando L. Rodriguez and Allan D. Coop are supported by NIH grant 3 R01 NS049288-06S1 to James M. Bower.

Ionisation in the absence of high voltage using supercritical fluid chromatography: a possible route to increased signal

Supercritical fluid chromatography (SFC) is fast becoming a technique of choice for the analysis of a wide range of compounds and has been found to be complementary to high-performance liquid chromatography (HPLC). The combination of SFC and mass spectrometry (MS) affords a very useful tool in the separation and analysis of compounds. In this study the ionisation of samples in the absence of an applied electrospray voltage has been observed when using SFC/MS, with some compounds showing increased sensitivity when all ionisation source high voltage (HV) is removed. In an attempt to understand the mechanism of ionisation, a series of test compounds were analysed using standard electrospray ionisation (ESI) and atmospheric pressure chemical ionisation (APCI) source configurations and also different API source designs. In both cases, data were acquired with the applied high voltage on (normal conditions) or with the high voltage off, i.e. no voltage spray (novo-spray). The standards were analysed with a range of pressure and modifier percentage conditions. To understand the nature of the ionisation process observed, this was compared with three established liquid-to-gas ionisation mechanisms. These were thermospray (TSP), charge residue model (CRM) of ESI and sonic spray ionisation (SSI). Experiments were undertaken in an attempt to explain this ionisation phenomenon and quantify any observed change in sensitivity. The most important point to note is that enhanced ionisation was observed under novo-spray conditions in a SFC/MS configuration, which in certain cases provides a lowering in the overall limit of detection (LOD).

Characterization of metabolites of a novel histamine H2‐receptor antagonist, lafutidine, in human liver microsomes by liquid chromatography coupled with ion trap mass spectrometry

The metabolism of lafutidine in human liver microsomes was studied using liquid chromatography/ion trap mass spectrometry with electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) sources. A total of 14 metabolites were identified including hydroxylated lafutidine and sulfonyl lafutidine as the major metabolites. The chemical properties and the MS(n) behaviors of lafutidine and all of its identified metabolites were studied in detail. Lafutidine had a fragmentation pattern as a result of homolytic bond cleavage in the MS/MS spectrum. This cleavage can form an odd-electron ion with the loss of furan-2-ylmethyl radical (-81 Da with a proton shift), which then sequentially loses neutral groups in the MS(3) spectrum. This fragmentation sequence was also observed from the metabolites with the unchanged sulfinyl moiety. When the sulfinyl moiety was oxidized to the sulfonyl moiety, this fragmentation sequence did not exist, which could be used to identify S-oxidation metabolites of lafutidine. In general, N-oxides could produce distinct [M+H-O](+) ions under LC/APCI-MS due to the thermal activation in the desolvation region of the API source, which could be used to identify N-oxidation metabolites of lafutidine. In order to avoid the possibility of false positives, the MS/MS spectrum of the [M+H-O](+) ion was compared with that of the non-N-oxidation metabolites or parent drug in the APCI source. If they were consistent, the structure could be finally confirmed. The exact masses for lafutidine and lafutidine N-oxide fragment ions were determined using an LTQ/Orbitrap mass spectrometer.

Microemulsion electrokinetic chromatography hyphenated to atmospheric pressure photoionization mass spectrometry

CZE is an appropriate technique for separating charged species, but lacks selectivity for neutral compounds. Alternative approaches such as microemulsion electrokinetic chromatography (MEEKC) have been developed to broaden its range of applications. Hyphenation of MEEKC with MS is an attractive perspective since it can enhance sensitivity and selectivity. The on-line coupling of MEEKC with MS, however, is not straightforward due to the low compatibility of non-volatile surfactant additives (e.g. SDS) and the commonly used API source, namely ESI. In order to hyphenate MEEKC with MS detection, the atmospheric pressure photoionization (APPI) source was investigated. Possibilities offered by the coupling of MEEKC with APPI-MS were highlighted for the complex separation of ionized and neutral compounds in both the positive and negative modes. MEEKC-APPI-MS performance, in terms of selectivity, efficiency and sensitivity was compared to CZE-ESI-MS and MEEKC-ESI-MS for the screening of doping substances (beta-blockers, central stimulants, diuretics, etc). Relevant selectivity and detectability, particularly for neutral, structurally related and isobaric compounds was demonstrated with the MEEKC-APPI-MS approach opening new avenues for CE-MS, in addition to the well-established CZE-ESI-MS technique.

High performance liquid chromatography/ion-trap mass spectrometry for separation and simultaneous determination of ethynylestradiol, gestodene, levonorgestrel, cyproterone acetate and desogestrel

A fast and highly sensitive high performance liquid chromatographic/ion-trap mass spectrometric method (LC/MS) has been developed for simultaneous determination of ethynylestradiol (EE2), gestodene (GES), levonorgestrel (LNG), cyproterone acetate (CPA) and desogestrel (DES). Among three types of sorbents tested (C8, C18 and phenyl) from two suppliers, the best separation was achieved on reverse phase Zorbax SB-Phenyl column using aqueous methanol as a mobile phase. A linear gradient profile from 70 up to 100% (v/v) in 7th min, kept constant at 100% up to 10th min and followed by a negative gradient to 70% of methanol up to 12th min was used for elution. Applicability of electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) and influence of the mobile phase composition, its flow rate, capillary/vaporizer temperature of API source and in-source fragmentor voltage ionization are discussed. The on-column limits of quantification (10 S/N) were 300 pg of EE2, 14 pg of GES and LNG, 4 pg of CPA and 960 pg of DES per injection (1 μL) using APCI with data collection in selected ion monitoring (SIM) mode. The analytical performance of the method was evaluated using the determination of EE2, GES, LNG, CPA and DES in contraceptives and river water samples.

Application of Deegree of Open Source Middleware to Geo-Portal Implementation

Recently, new GIS applications such as gee portal and spatial data infrastructure are emerging. These are related to web computing techniques or methodologies based on web 2.0 paradigm, open API of portal, open source GIS, and international GIS standards which are independently on developing. The product of these applications can be realized in the linkage of those components. In this study, a case implementation concerning linkage with Google maps API and open source middleware named Deegree is carried out, and the results are discussed for open source uses in geo portal. Open source middleware supports various levels and types of OGC standards, so that it enables web publishing in the several web standard formats and data exchanges and interoperable uses between external database servers. Also the (unction extensions and the multi tier-based architecture within geo portal for specific purpose are possible.

An API LC/MS/MS quantitation method for ansamitocin P-3 (AP3) and its preclinical pharmacokinetics

Ansamitocin P-3 (AP3) is a potent maytansinoid antitumor agent isolated from microorganisms and mosses. In this study, a highly sensitive and specific electrospray ionization (ESI) liquid chromatography–tandem mass spectrometry (LC/MS/MS) method for quantitation of AP3 was developed and validated. AP3 was extracted from rat plasma along with the internal standard, depsipeptide FK228 (NSC-630176, FR) with ethyl acetate. Components in the extract were separated on a 50 mm × 2.1 mm Betabasic C 85 μm stainless steel column by isocratic elution with 70% acetonitrile/0.9% formic acid. The liquid flow was passed through a pre-source splitter and 5% of the eluent was introduced into the API source. The components were analyzed in the multiple-reaction-monitoring (MRM) mode as the precursor/product ion pair of m/ z 635.2/547.2 for AP3 and of m/ z 541.5/424.0 for the internal standard FR. Linear calibration curves were obtained in the range 1–500 ng/mL using 0.2 mL rat plasma. The within-day coefficients of variation (CVs) were 12.9, 6.7, and 5.5% and the between-day CVs were 10.4, 6.5, and 6.4% (all n = 5) at 1, 10, and 200 ng/mL, respectively. A formulation based on normal saline and PEG300 was then developed and Sprague–Dawley male rats were given this formulated drug by i.v. bolus. Plasma drug concentrations were measured by this method and the pharmacokinetics were analyzed by standard techniques. Plasma concentration–time profiles were found to follow a triexponential decline and the terminal phase was nearly flat, suggesting that the drug distributed in deep tissue compartments or organs and then equilibrates slowly with the blood stream.

Matrix effect in LC-ESI-MS and LC-APCI-MS with off-line and on-line extraction procedures

Matrix effect on mass spectrometry response was investigated with commercially available electrospray ionisation (ESI) and atmospheric pressure chemical ionisation (APCI) sources coupled with a single quadruple mass spectrometer. A post-column infusion system was used to observe the MS signal alterations of methadone, selected as the model compound, in plasma. For this purpose, two sample preparation procedures were tested: (1) conventional off-line sample preparations with liquid–liquid extraction (LLE), solid-phase extraction (SPE) and protein precipitation (PP) with perchloric acid (PA) and acetonitrile (ACN) and (2) on-line SPE with two different extraction columns packed with a large particle support (LPS) and with restricted access material (RAM), respectively. Whatever the sample preparation procedures, APCI source appeared to be less liable to matrix effect than ESI source. Among the different off-line sample preparations, LLE was the most efficient extraction procedure. With other techniques, MS signal was affected not only by endogenous material but also by procedure introduced compounds. Moreover, on-line SPE-LC-MS configuration exhibited matrix effects, which depend on the API source and the extraction support.

Progress of liquid chromatography-mass spectrometry in clinical and forensic toxicology.

The use of liquid chromatography-mass spectrometry (LC-MS) has recently exploded in various analytic fields, including toxicology and therapeutic drug monitoring (although still far behind pharmacokinetics). There is no doubt that LC-MS is currently competing with gas chromatography (GC)-MS for the status of the reference analytic technique in toxicology. This review presents, for the nonspecialist reader, the principles, advantages, and drawbacks of LC-MS systems using atmospheric pressure interfaces. It also gives an overview of the analytic methods for xenobiotics that could be set up with these instruments for clinical or forensic toxicology. In particular, as far as quantitative techniques are concerned, this review tries to underline the large number and variety of drugs or classes of drugs (drugs of abuse, therapeutic drugs) or toxic compounds (e.g., pesticides) that can be readily determined using such instruments, the respective merits of the different ionization sources, and the improvements brought about by tandem MS. It also discusses new applications of LC-MS in the field of toxicology, such as "general unknown" screening procedures and mass spectral libraries using LC-atmospheric pressure ionization (API)-MS or MS-MS, presenting the different solutions proposed to overcome the naturally low fragmentation power of API sources. Finally, the opportunities afforded by the most recent or proposed instrument designs are addressed.

Fragmentation of N-oxides (deoxygenation) in atmospheric pressure ionization: investigation of the activation process.

The diagnostic fragmentation of N-oxides resulting from loss of the oxygen atom (MH+ --> MH+-O) in electrospray and atmospheric pressure chemical ionization (APCI) mass spectra was investigated. When the temperature of the heated capillary tube was elevated, the ratio of the intensity of the [MH+ -16] fragment to the precursor ion (MH+) increased. This 'deoxygenation' process was associated with thermal activation and did not result from collisional activation in the desolvation region of the API source. Although the extent of 'deoxygenation' is compound-dependent, it can provide evidence for the presence of an N-oxide in a sample and can be used to distinguish N-oxides from hydroxylated metabolites (Ramanathan et al. Anal. Chem. 2000; 72: 1352). To demonstrate the practical application of thermal fragmentation of N-oxides, liquid chromatography (LC)/APCI-MS was used to distinguish an N-oxide drug from its hydroxylated metabolite in an unprocessed rat urine sample, despite the fact that the drug and its metabolite were not fully resolved by HPLC.

Determination of Aniline Derivatives in Oils Related to the Toxic Oil Syndrome by Atmospheric Pressure Ionization-Tandem Mass Spectrometry

In 1981, an unknown disease appeared in Spain, the Spanish Toxic Oil Syndrome. Nowadays and despite all efforts, the etiological agent is still unknown. Early studies showed a link between this illness and the consumption of denatured rapeseed oil fraudulently processed and marketed as edible oil. Two families of aniline derivatives present in these oils (fatty acid anilides and acylated phenyl amino propanediol derivatives or PAPs) were found to be good chemical markers of toxic oils. In this work, a new method has been developed to analyze these aniline derivatives in oil samples by HPLC-MS and HPLC-MS/MS with an API source. For their quantification, three different internal standards were used, one for anilides and two for PAPs. Quantification limits were 8 ppm for anilides and 0.2 ppm for PAPs. Anilides and PAPs were found in marker-positive samples at levels up to 50,000 and 330 ppm, respectively. The relative abundance of the different fatty acid anilides and PAPs correlates with the fatty acid composition of the oils. More than 2,600 different samples were analyzed by this method in the most exhaustive screening of suspected toxic oils carried out to date.