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Paper spray ionization (PSI-MS) and tissue spray ionization (TSI-MS) mass spectrometry are simple and rapid ambient ionization mass spectrometry techniques that offer numerous advantages over conventional analysis methods. This study aims to analyze the efficiency of detecting anthocyanins from Eugenia jambolana fruit peel and Inga edulis seeds using PSI-MS, TSI-MS, and DI-MS (direct infusion). DI-MS exhibited high efficiency, detecting all compounds in abundance, with anthocyanins malvidin 3,5-O-diglucoside (1) and petunidin 3,5-O-diglucoside (2) being the most prevalent. PSI-MS, however, struggled to detect delphinidin 3-O-glucoside and showed lower abundances for compounds 1, 2, 3 (delphinidin 3,5-O-diglucoside), and 4 (petunidin 3-O-glucoside) compared to DI-MS, attributed to the technique's challenges with molecular weight and polarity. TSI-MS was least effective, detecting only compounds 1, 2, and 3 at low intensities. The overall unique compounds identified across techniques were 134, emphasizing the importance of comprehensively employing multiple methods to analyze anthocyanins in these edible plants.

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This research focused on the molecular diversity of A. carambola collected from three Brazilian biomes (Cerrado, Amazônia, and Mata Atlântica), whose results revealed significant differences in metabolite profiles among these biomes through PSI-MS analysis. Chemometric analysis provided valuable insights into the clustering patterns and metabolic distinctions. Cerrado and Mata Atlântica biomes exhibited a 70 % similarity, indicating a notable degree of resemblance. In Cerrado, carambolaside A was notably abundant, while carambolaside M was low in Amazônia and moderate in Cerrado samples. Carambolaside B was abundant in Amazônia but relatively low in the Cerrado and Mata Atlântica. In contrast, the Amazônia biome samples appeared to be more dissimilar. In Cerrado, epicatechin, kaempferol, and procyanidin B showed lower abundance, while apigenin, quercetin, myricetin, and rutin displayed moderate levels. Mata Atlântica showed relatively higher levels of kaempferol, quercetin, and rutin. This study indicated the environmental influence on secondary metabolites production in A. carambola fruits.

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Paper spray mass spectrometry (PS-MS) is an ambient ionization technique that allows for rapid and direct mass spectrometry analysis for a wide range of chemical compounds due to its portability, little to no sample preparation, and cost-effective materials. As applications with this technique continue to expand, the identification and discrimination of bacteria at the strain level remain a promising avenue for researchers. Although studies in the past demonstrated the applicability of PS-MS to discriminate bacteria at the strain level, no one has reported the strain-level differentiation of actinobacteria without using solvent for PS-MS. Hence, this study demonstrates that optimization of PS-MS permits the investigation and differentiation of the metabolic profiles of actinobacteria without the need for solvents, diminishing the potential for sample contamination and consequently increasing the versatility of this technique. In doing so, strains of actinobacteria (CAAT P5-21, CAAT P5-16, CAAT 8-25, CAAT P8-92, and CAAT P11-13) were grown and transferred to produce a crude growth medium. The supernatant was used for the PS-MS analyses using a Thermo Scientific LTQ mass spectrometer. Multivariate statistical analysis, including principal component analysis (PCA) and hierarchal cluster analysis (HCA), was employed to chemically distinguish the strains of bacteria. As a result, each strain of actinobacteria could be visually differentiated based on their metabolic profile. These findings demonstrate the practicability of using a liquid medium as an alternative to many other organic solvents when analyzing bacteria, making PS-MS a crucial addition to a microbiologist's research toolkit.

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Pereskia aculeata Miller, is an unconventional food plant native to South America. This study aimed to investigate the influence of different ultrasonic extraction times (10, 20, 30, and 40 min) on the phytochemical profile, antioxidant and antibacterial activities of ethanolic extracts obtained from lyophilized Pereskia aculeate Miller (ora-pro-nobis) leaves, an under-researched plant. Morphological structure and chemical group evaluations were also conducted for the lyophilized P. aculeate leaves. The different extraction times resulted in distinct phenolic content and Antioxidant Activity (ATT) values. Different extraction time conditions resulted in phenolic compound contents ranging from 2.07 to 2.60 mg EAG.g-1 of extract and different ATT values. The ATT evaluated by DPPH was significantly higher (from 61.20 to 70.20 µM of TE.g-1 of extract) in extraction times of 30 and 40 min, respectively. For ABTS, it varied between 6.38 and 10.24 µM of TE.g-1 of extract and 24.34 and 32.12 µM ferrous sulp.g-1 of extract. All of the obtained extracts inhibited the growth of Staphylococcus aureus, particularly the treatment employing 20 min of extraction at the highest dilution (1.56 mg.mL-1). Although liquid chromatography analyses showed that chlorogenic acid was the primary compound detected for all extracts, Paper Spray Mass Spectrometry (PS-MS) suggested the extracts contained 53 substances, such as organic, fatty, and phenolic acids, sugars, flavonoids, terpenes, phytosterols, and other components. The PS-MS proved to be a valuable technique to obtain the P. aculeate leaves extract chemical profile. It was observed that the freeze-drying process enhanced the conservation of morphological structures of P. aculeate leaves, as evidenced by scanning electron microscopy (SEM). Fourier transform infrared spectroscopy (FTIR) identified carboxyl functional groups and proteins between the 1000 and 1500 cm-1 bands in the P. aculeate leaves, thus favoring water interaction and contributing to gel formation. To the best of our knowledge, this is the first study to evaluate different times (10, 20, 30 and 40 min) for ultrasound extraction of P. aculeate leaves. The polyphenols improved extraction, and high antioxidant activity demonstrates the potential for applying P. aculeate leaves and their extract as functional ingredients or additives in the food and pharmaceutical industries.

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Employing a combination of liquid chromatography electrospray ionization and paper spray ionization high-resolution tandem mass spectrometry, extracts from cupuassu (Theobroma grandiflorum) pulp prepared with either water, methanol, acetonitrile or combinations thereof were subjected to metabolite fingerprinting. Among the tested extractors, 100% methanol extracted preferentially phenols and cinnamic acids derivatives, whereas acetonitrile and acetonitrile/methanol were more effective in extracting terpenoids and flavonoids, respectively. And while liquid chromatography- mass spectrometry detected twice as many metabolites as paper spray ionization tandem mass spectrometry, the latter proved its potential as a screening technique. Comprehensive structural annotation showed a high production of terpenes, mainly oleanane triterpene derivatives. of the mass spectra Further, five major metabolites with known antioxidant activity, namely catechin, citric acid, epigallocatechin-3'-glucuronide, 5,7,8-trihydroxyflavanone, and asiatic acid, were subjected to molecular docking analysis using the antioxidative enzyme peroxiredoxin 5 (PRDX5) as a model receptor. Based on its excellent docking score, a pharmacophore model of 5,7,8-trihydroxyflavanone was generated, which may help the design of new antioxidants.

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Avocado (Persea americana) is a widely consumed fruit and a rich source of nutrients and phytochemicals. Its industrial processing generates peels and seeds which represent 30% of the fruit. Environmental issues related to these wastes are rapidly increasing and likely to double, according to expected avocado production. Therefore, this work aimed to evaluate the potential of hexane and ethanolic peel (PEL-H, PEL-ET) and seed (SED-H, SED-ET) extracts from avocado as sources of neuroprotective compounds. Minerals, total phenol (TPC), total flavonoid (TF), and lipid contents were determined by absorption spectroscopy and gas chromatography. In addition, phytochemicals were putatively identified by paper spray mass spectrometry (PSMS). The extracts were good sources of Ca, Mg, Fe, Zn, ω-6 linoleic acid, and flavonoids. Moreover, fifty-five metabolites were detected in the extracts, consisting mainly of phenolic acids, flavonoids, and alkaloids. The in vitro antioxidant capacity (FRAP and DPPH), acetylcholinesterase inhibition, and in vivo neuroprotective capacity were evaluated. PEL-ET was the best acetylcholinesterase inhibitor, with no significant difference (p > 0.05) compared to the control eserine, and it showed neither preventive nor regenerative effect in the neuroprotection assay. SED-ET demonstrated a significant protective effect compared to the control, suggesting neuroprotection against rotenone-induced neurological damage.

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Paper spray ionization mass spectrometry (PS-MS) is employed herein as a convenient platform to investigate an on-surface catalytic process, that is, the oxidation of alcohols induced by ruthenium salts. The tag-charged benzyl alcohol 1 (m/z 166), used as a suitable prototype starting substrate, is quickly oxidized by tert-butyl hydroperoxide (TBHP) in an on-surface process catalyzed by ruthenium trichloride (RuCl3). The PS(+)-MS revealed the formation of products from the oxidation of alcohol 1. RuCl3 and TBHP played a crucial role in this process since when salts of other metals (platinum, palladium, and iron) and another oxidizing agent (hydrogen peroxide) are employed, no reaction is observed. Moreover, UV radiation and heating accelerate the on-surface alcohol 1 oxidation. Finally, an exciting possibility is to employ PS-MS to investigate similar organic catalytic reactions to accelerate them and detect unstable intermediates, indiscernible in the condensed phase.

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Concerns about human health regarding the large use of bisphenol A in thermal papers have led to its replacement by bisphenol S. Analyses of bisphenols require several sample pretreatment steps, which are laborious, expensive, and time-consuming. A paper spray ionization mass spectrometry (PSI-MS) was developed to detect and quantify bisphenol S in three different brands of thermal papers commercially available. Parameters such as paper size, and paper position relative to the mass spectrometer inlet were evaluated. The analyses were performed in selected ion monitoring mode on a linear ion trap mass spectrometer. The developed method presented absolute recovery values ranging from 92.2 to 109.04%, accuracy values from -1.2 to 9.0%, and inter assay precision from 1.8 to 5.6% and enabled LOD as low as 5 ng g-1. The concentration of bisphenol S in all of the three brands of BPA-free thermal papers evaluated ranged from 1.36 to 6.77 µg g-1, and the concentrarion of BPA ranged from 6.56 to 16.4 µg g-1 in all samples of thermal paper evaluated. The PSI-MS method described here was comparable to the conventional ones, such as liquid chromatography coupled with mass spectrometry and gas chromatography coupled with mass spectrometry described in the literature. The present study proved to be practical, fast, and efficient for the direct determination of bisphenol S in thermal papers. Furthermore, the methodology here described showed to be a promising alternative to replace the classical methods for determination of bisphenol S, due to its simplicity, and no needing of any sample pretreatment.

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The recent developments on fieldable miniature mass spectrometers require efforts to produce easy-to-use and portable alternative tools to assist in point-of-care analysis. In this paper, the reagent-pencil (RP) technology, which has been used for solvent-free deposition of reagents in paper-based microfluidics, was combined with paper spray ionization mass spectrometry (PS-MS). In this approach, named RP-PS-MS, the PS triangular piece of paper was written with the reagent pencil, consisting of mixtures of graphite and bentonite (used as a support) and a reactive compound, and allowed to react with a given analyte from a sample matrix selectively. We conducted typical applications as proof-of-principles to verify the methodology's general usefulness in detecting small organic molecules in distinct samples. Hence, various aldehydes (2-furaldehyde, valeraldehyde, and benzaldehyde) in spiked cachaça samples (an alcoholic drink produced from fermentation/distillation of sugarcane juice) were promptly detected using a reagent pencil doped with 4-aminophenol (the reactive compound). Similarly, we recognized typical ginsenosides and triacylglycerols (TAGs) in ginseng aqueous infusions and soybean oil samples, respectively, using lithium chloride as the reactive compound. The results indicate that the reagent-pencil methodology is compatible with PS-MS and provides an easy and fast way to detect target analytes in complex samples. The advantage over the usual solution-based deposition of reagents lies in the lack of preparation or carrying different specific solutions for special applications, which can simplify operation, especially in point-of-care analysis with fieldable mass spectrometers.

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In this work, for the first time, chromatographic paper was used for a multiphase extraction assisted by an electric field (MPEF) and directly coupled to paper spray mass spectrometry (PS-MS). Using this approach, five tricyclic antidepressants (TCAs) were determined in oral fluid. Firstly, the MPEF conditions were optimized using liquid chromatography-mass spectrometry (LC-MS/MS). The effects of the chromatographic paper and the types of electrolyte used in the acceptor phase, the organic solvent type and the amount used in the donor phase, the extraction time, and the applied electric potential were all investigated. After optimization, the analytes were extracted from the donor solution (sample and acetonitrile 1:1 (v/v)) over a period of 10 min at 300 V, crossing the free liquid membrane (1-octanol) and reaching the acceptor phase (chromatographic paper wetted with 400 mmol L-1 acetic acid). The method using LC-MS/MS was validated, demonstrating a linear range from 2 to 12 ng mL-1, with detection and quantification limits of 0.13-0.25 and 0.44-0.84 ng mL-1, respectively, an intraday precision of less than 20%, and no matrix effect observed. The optimized MPEF conditions were then applied to determine TCAs by PS-MS and for this analysis cyclobenzaprine was used as an internal standard. The easy, fast and direct approach of coupling MPEF with PS-MS analysis, as well as the pre-concentration and the low standard deviation of replicates (less than 20%), demonstrates that this method can be useful for screening in clinical and toxicological analysis.

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Os esteroides anabólicos androgênicos (EAA) são utilizados clinicamente para tratar diferentes doenças, porém propagou-se o uso não terapêutico por atletas de elite e fisiculturistas, com o intuito de aumentar a massa muscular e melhorar o desempenho físico. O uso de substâncias ergogênicas, como fármacos estimulantes e narcóticos analgésicos no esporte, foi proibido em 1967 pelo International Olympic Committee (COI), mas somente em 1976 os EAA entraram para a lista de substâncias proibidas. O uso de EAA está associado a diversos efeitos adversos, principalmente cardiovasculares, neuroendócrinos e distúrbios psiquiátricos, além de dislipidemia, elevação dos marcadores inflamatórios e disfunção endotelial. As análises toxicológicas constam como a maneira mais eficaz de minimizar o doping no esporte. O material é fornecido pelo atleta durante as competições ou treinamentos e previne que os competidores alcancem vantagem competitiva devido ao uso de EAA. A utilização de métodos para amostragem alternativos tem ganhado força, devido à necessidade de técnicas mais práticas que utilizam pouco volume de amostra e possuem facilidade de armazenamento. O dried urine spots é um método no qual pequenas amostras de urina são aplicadas em papéis de filtro para análises qualitativas ou quantitativas. Ele se caracteriza por ser uma técnica rápida, fácil, simples e barata para a coleta, armazenamento e distribuição, além de minimizar os riscos de infecção, podendo ser utilizado na rotina. A técnica de paper spray (PS-MS) foi desenvolvida a partir da relevância de métodos como o dried blood spots por proporcionar análises mais rápidas, apresenta alta especificidade, capacidade de analisar diferentes analitos simultaneamente, baixo limite de detecção e dispensa a necessidade de reagentes específicos. Sendo assim, neste trabalho foi desenvolvido e validado o método de screening de EAAs em dried urine spots por ionização por paper spray acoplada à espectrometria de massas. O método apresentou limites de detecção entre 2-15ng/mL e presença de três interferentes endógenos. Os dez analitos de interesse deste estudo são estáveis por 150 dias em temperatura ambiente. Dessa forma, a análise de EAAs em dried urine spots por PS-MS demonstra grande potencial para se tornar um método alternativo no monitoramento rápido de drogas de abuso

Anabolic androgenic steroids (AAS) are used clinically to treat different diseases, but non-therapeutic use has spread among elite athletes and bodybuilders, with the aim of increase muscle mass and improve physical performance. The International Olympic Committee (IOC) banned the use of ergogenic substances, such as stimulating drugs and analgesic narcotics in sports, in 1967, but only in 1976, AAS were included on the list of prohibited substances. The use of AAS is associated with several adverse effects, mainly cardiovascular, neuroendocrine and psychiatric disorders, in addition to dyslipidemia, elevated inflammatory markers and endothelial dysfunction. Toxicological analyzes are the most effective approach to minimize doping in sport. The material is provided by the athlete during competitions or training and prevents competitors from achieving a competitive advantage due to the use of AAs. The use of alternative sampling methods has gained strength, due to the need for more practical techniques that use low sample volume and can be easily storage. Dried urine spots are a method, which a small amount of urine samples is applied to filter papers for qualitative or quantitative analysis. It is characterized by being a fast, easy, simple and inexpensive technique for collection, storage and distribution, in addition to minimizing the risks of infection, and can be used in the routine. The paper spray technique (PS-MS) was developed based on the relevance of methods such as dried blood spots for providing faster analysis, high specificity, ability to analyze different analytes simultaneously, low detection limit and for eliminating the need for specific reagents. Therefore, this work developed and validated a screening method for AAS in dried urine spots by paper spray-mass spectrometry ionization. The method provided detection limits between 2-15ng/mL and the presence of three endogenous interferents. The ten analytes of interest in this study are stable for 150 days at room temperature. Thus, the analysis of AAS in dried urine spots by PS-MS demonstrates great potential to become an alternative method for the rapid monitoring of drugs of abuse

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Direct ambient ionization techniques have been developed with the aim to reduce the complexity of mass spectrometry analysis by minimizing sample preparation and chromatographic separation. In this context, paper spray-MS (PS-MS) is an innovative approach that provides faster and cheaper analysis of biofluids by the addition of the sample directly to a paper. In forensic toxicology, the analytical workflow for the detection and quantification of drugs of abuse is onerous, including sample treatment, extraction and clean up, especially regarding complex biological matrices. PS-MS allows the detection of analytes of toxicological interest in blood, plasma and urine using low sample volume. This review aims to discuss the potential use, advances and challenges of PS-MS in forensic toxicology.

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Squamous intraepithelial lesion is an abnormal growth of epithelial cells on the surface of the cervix that may lead to cervical cancer. Analytical protocols for the determination of squamous intraepithelial lesions are in high demand, since cervical cancer is the fourth most diagnosed cancer among women in the world. Here, paper spray ionization mass spectrometry (PSI-MS) is used to distinguish between healthy (negative for intraepithelial lesion or malignancy) and diseased (high-grade squamous intraepithelial lesion) blood plasmas. A total of 86 blood samples of different women (49 healthy samples, 37 diseased samples) were collected, and the plasmas were prepared. Then, 10 µL of each plasma sample was deposited onto triangular papers for PSI-MS analysis. No additional step of sample preparation was necessary. The interval-successive projection algorithm linear discriminant analysis (iSPA-LDA) was applied to the PSI mass spectra, showing six ions (mostly phospholipids) that were predictive of healthy and diseased plasmas. Values of 77% accuracy, 86% sensitivity, 80% positive predictive value (PPV), and 75% negative predictive value (NPV) were achieved. This study provides evidence that PSI-MS may potentially be used as a fast and simple analytical technique for the early diagnosis of cervical cancer.

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A method named imprint paper spray ionization mass spectrometry (imprint-PSI-MS) has been developed and employed for the determination of pungency of peppers. A pepper fruit was cut into a triangular shape, deposited onto a triangular paper, and compressed by a homemade press tool aiming to imprint and transfer the pepper constituents onto the paper surface. Subsequently, the triangular paper was submitted to conventional PSI-MS analysis. Twelve peppers were analyzed, ranging from highly pungent to lowly pungent taste. Pepper pungency values from the Scoville scale (in Scoville heat units, SHU) were compared with the ion intensities of the capsaicin and dihydrocapsaicin compounds obtained from the imprint-PSI-MS analysis, and a correlation coefficient of 0.97 was achieved. In addition, the ion intensities of a sugar compound were monitored in all peppers, and the results were compared with the Scoville scale. Low sugar ion intensities were detected in pungent peppers, while high ion intensities were achieved in low-pungent peppers, suggesting that the pepper pungency may be determined by inversely relating pungency to sugar contents. This work demonstrates the utility of the imprint-PSI-MS method to perform rapid qualitative analyses of peppers and estimate the pungency by monitoring the pepper metabolites. Graphical abstract.

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This work describes a novel methodology to analyze four tricyclic antidepressants (amitriptyline, doxepin, imipramine and, nortriptyline) in urine samples by combining supramolecular microextraction and paper spray ionization mass spectrometry (PS-MS). The proposed method uses a supramolecular solvent in which reverse micelles of 1-decanol are dispersed in tetrahydrofuran (THF)/water. The extraction of the tricyclic antidepressants at pH 9.0 requires a sample volume of 10.0 mL, short extraction time (1.0 min of extraction and 5 min of centrifugation), low amounts of organic solvent (50 µL of 1-decanol and 200 µL of THF), and provides high preconcentration factors: 96.9 to amitriptyline, 93.6 to doxepin, 71.3 to imipramine, and 146.9 to nortriptyline. The quantification by PS-MS is fast and straightforward because chromatographic separation is not required and all analytes were determined simultaneously. The limits of detection (LOD), quantification (LOQ), and the precision (RSD, %) of the developed method ranged between 5.2 and 8.6 µg L-1, 17.4-28.7 µg L-1 and 1.3-12.9%, respectively. Urine samples of five individuals (three males and two females) were used for accuracy evaluation. The accuracy obtained in these spiked urine samples at µg L-1 levels varied from 95.3 to 112.0%. The method also provided clean mass spectra with a high signal-to-noise ratio, which demonstrates the analytical appeal combination of supramolecular microextraction with determination by paper spray mass spectrometry.

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A rapid analysis of acephate, chlorpyrifos, and cyazofamid in tomato peels during pre-harvest intervals using paper spray ionization mass spectrometry (PSI-MS) has been demonstrated. LODs of 0.01 ppm and LOQs of 0.03 ppm were achieved. Relative standard deviations were below 9%, and recoveries close to 100%. For pesticides monitoring, samples were separated into stored and field groups. Stored group contained fruits that were harvested and stored at low temperature during the pre-harvest interval, and the field group contained fruits that were on the agricultural field over the pre-harvest interval. The decrease in pesticide amounts was lower for the stored samples. At the end of the pre-harvest intervals, acephate, chlorpyrifos, and cyazofamid were determined at 0.86, 0.96, and 0.23 ppm in the stored group, and at 0.26, 0.37, and 0.09 ppm in the field group, respectively. This work demonstrates the utility of PSI-MS for performing rapid quality control of fruit harvesting.

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This paper describes a robust multivariate model for quantifying and characterizing blends of Robusta and Arabica coffees. At different degrees of roasting, 120 ground coffee blends (0.0-33.0%) were formulated. Spectra were obtained by two different techniques, attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and paper spray mass spectrometry (PS-MS). Partial least squares (PLS) models were built individually with the two types of spectra. Nevertheless, better predictions were obtained by low and medium-level data fusion, taking advantage from the synergy between these two data sets. Data fusion models were improved by variable selection, using genetic algorithms (GA) and ordered predictors selection (OPS). The smallest prediction errors were provided by OPS low-level data fusion model. The number of variables used for regression was reduced from 2145 (full spectra) to 230. Model interpretation was performed by assigning some of the selected variables to specific coffee components, such as trigonelline and chlorogenic acids.

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On-surface degradation of sildenafil (an adequate substrate as it contains assorted functional groups in its structure) promoted by the Fenton (Fe2+ /H2 O2 ) and Fenton-like (Mn+ /H2 O2 ; Mn+  = Fe3+ , Co2+ , Cu2+ , Mn2+ ) systems was investigated by using paper spray ionization mass spectrometry (PS-MS). The performance of each system was compared by measuring the ratio between the relative intensities of the ions of m/z 475 (protonated sildenafil) and m/z 235 (protonated lidocaine, used as a convenient internal standard and added to the paper just before the PS-MS analyzes). The results indicated the following order in the rates of such reactions: Fe2+ /H2 O2  â‰« H2 O2  â‰« Cu2+ /H2 O2  > Mn+ /H2 O2 (Mn+  = Fe3+ , Co2+ , Mn2+ ) ~ Mn+ (Mn+  = Fe2+ , Fe3+ , Co2+ , Cu2+ , Mn2 ). The superior capability of Fe2+ /H2 O2 in causing the degradation of sildenafil indicates that Fe2+ efficiently decomposes H2 O2 to yield hydroxyl radicals, quite reactive species that cause the substrate oxidation. The results also indicate that H2 O2 can spontaneously decompose likely to yield hydroxyl radicals, although in a much smaller extension than the Fenton system. This effect, however, is strongly inhibited by the presence of the other cations, ie, Fe3+ , Co2+ , Cu2+ , and Mn2+ . A unique oxidation by-product was detected in the reaction between Fe2+ /H2 O2 with sildenafil, and a possible structure for it was proposed based on the MS/MS data. The on-surface reaction of other substrates (trimethoprim and tamoxifen) with the Fenton system was also investigated. In conclusion, PS-MS shows to be a convenient platform to promptly monitor on-surface oxidation reactions.

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A novel methodology using liquid-liquid extraction with low temperature partitioning (LLE-LTP) and paper spray mass spectrometry (PS-MS) was developed to identify and quantify benzodiazepines in beverages. Four types of alcoholic beverages usually consumed in parties and bars were spiked with 5 distinct benzodiazepines (diazepam, alprazolam, bromazepam, clonazepam, and cloxazolam) simulating a drug-facilitated crime occurrence. The direct PS-MS analysis of the spiked beverages revealed a remarkable matrix effect with an unclear detection of protonated benzodiazepines. However, by the application of the LLE-LTP using liquid nitrogen, a prompt and doubtless detection of such compounds was achieved. The quantification potential of the LLE-LTP/PS-MS methodology was demonstrated by using beer as matrix, diazepam as target analyte and cloxazolam as an internal standard. Figures of merit (linearity, limit of detection, linear dynamic range, relative standard deviation, and recovery) were determined and adequate values were obtained. In conclusion, we demonstrated herein that the LLE-LTP/PS-MS methodology has potential to be applied directly at the crime scene through of a portable mass spectrometer and a thermal container for the transport of liquid nitrogen.

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This study proposes a new direct and fast method of analysis employing paper spray mass spectrometry (PS-MS). The paper used in the proposed method was modified with molecularly imprinted polymers (MIP) to create a specific site for cocaine analysis in oral fluid. MIP membrane was successfully synthetized and employed. The developed method showed to be linear in a concentration range from LOQ to 100 ng mL-1. The experimental value of LOQ obtained was 1 ng mL-1. The inter-day and intra-day precision and accuracy of the PS-MS method presented values lower than 15%. The total recoveries were also evaluated. The PS-MS method for the analysis of cocaine in oral fluid showed to be very promising and the validation parameters showed a good correlation with the literature. Graphical abstract ᅟ.

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