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Archaeological textiles represent precious remains from ancient culture; this is because of the historical and cultural importance of the information that can be obtained by such relics. However, the extremely complicated state of preservation of these textiles, which can be charred, partially or totally mineralized, with heavy soil or biological contamination, requires highly specialized and sensitive analytical tools to perform a comprehensive study. Starting from these considerations, the paper presents a combined workflow that provides the extraction of dyes and keratins and keratin-associated proteins in a single step, minimizing sampling while maximizing the amount of information gained. In the first phase, different approaches were tested and two different protocols were found suitable for the purpose of the unique workflow for dyes/keratin-proteins: a slightly modified urea protocol and a recently proposed new TCEP/CAA procedure. In the second step, after the extraction, different methods of cleanup and workflow for proteins and dyes were investigated to develop protocols that did not result in a loss of aliquots of the analytes of interest and to maximize the recovery of both components from the extracting solution. These protocols investigated the application of two types of paramagnetic beads, unmodified and carboxylate-coated hydrophilic magnetic beads, and dialysis and stage-tip protocols. The newly designed protocols have been applied to cochineal, weld, orchil, kermes, and indigo keratin-based dyed samples to evaluate the effectiveness of the protocols on several dye sources. These protocols, based on a single extraction step, show the possibility of investigating dyes and keratins from a unique sample of 1 mg or lesser, with respect to the thresholds of sensitivity and accuracy required in the study of textile artifacts of historical and artistic values.
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To date, it is still not possible to obtain exhaustive information about organic materials in cultural heritage without sampling. Nonetheless, when studying unique objects with invaluable artistic or historical significance, preserving their integrity is a priority. In particular, organic dye identification is of significant interest for history and conservation research, but it is still hindered by analytes' low concentration and poor fastness. In this work, a minimally invasive approach for dye identification is presented. The procedure is designed to accompany noninvasive analyses of inorganic substances for comprehensive studies of complex cultural heritage matrices, in compliance with their soundness. Liquid extraction of madder, turmeric, and indigo dyes was performed directly from paint layers and textiles. The extraction was supported by hydrogels, which themselves can undergo multitechnique analyses in the place of samples. After extraction, Ag colloid pastes were applied on the gels for SERS analyses, allowing for the identification of the three dyes. For the HPLC-MS/MS analyses, re-extraction of the dyes was followed by a clean-up step that was successfully applied on madder and turmeric. The colour change perceptivity after extraction was measured with colorimetry. The results showed ΔE values mostly below the upper limit of rigorous colour change, confirming the gentleness of the procedure.
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The introduction of synthetic dyes completely changed the industrial production and use of colorants for art materials. From the synthesis of the first synthetic dye, mauveine, in 1856 until today, artists have enjoyed a wider range of colors and selection of chemical properties than was ever available before. However, the introduction of synthetic dyes introduced a wider variety and increased the complexity of the chemical structures of marketed dyes. This work looks towards the analysis of synthetically dyed objects in heritage collections, applying an extraction protocol based on the use of ammonia, which is considered favorable for natural anthraquinone dyes but has never before been applied to acid synthetic dyes. This work also presents an innovative cleanup step based on the use of an ion pair dispersive liquid-liquid microextraction for the purification and preconcentration of historical synthetic dyes before analysis. This approach was adapted from food science analysis and is applied to synthetic dyes in heritage science for the first time in this paper. The results showed adequate recovery of analytes and allowed for the ammonia-based extraction method to be applied successfully to 15 samples of suspected azo dyes from the Azienda Coloranti Nazionali e Affini (ACNA) synthetic dye collection, identified through untargeted HPLC-HRMS analyses.
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The identification of the dyes present on a linen fragment from the tomb of Pharaoh Tutankhamun is the objective of the present study. Fiber optic reflectance spectroscopy (FORS) was applied to the archaeological sample for preliminary identification of the dyes and to better choose the extraction methodology for different areas of the sample. The innovative gel-supported micro-extraction with agar gel and the Nanorestore Gel® High Water Retention (HWR) gel were applied to the archaeological sample after testing of the best concentration for the extraction of the agar gels substrates, performed on laboratory mock-ups by means of UV-Vis transmittance spectroscopy. Immediately after extraction, Ag colloidal pastes were applied on the gel surface and Surface Enhanced Raman Scattering (SERS) analysis was performed directly on them. The combination of information deriving from FORS and SERS spectra resulted in the successful identification of both indigo and madder and, in hypothesis, of their degradation products.
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The phytochemical analysis on the aerial parts of Teucrium capitatum L. collected from a new population in Central Italy, led to the identification of eight compounds, i.e. pheophytin a (1), poliumoside (2), apigenin (3), luteolin (4), cirsimaritin (5), cirsiliol (6), 8-O-acetyl-harpagide (7) and teucardoside (8) belonging to four different classes of secondary metabolites. Pheophytin a (1) represents a newly identified compound in the genus whereas compounds (7-8) are newly identified compound in the species. The chemotaxonomic and ethnobotanical aspects relative to the presence of these compounds were widely discussed suggesting important conclusions for both.
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Teucrium , Teucrium/química , Etnobotánica , Extractos Vegetales/química , Fitoquímicos/análisis , Componentes Aéreos de las Plantas/químicaRESUMEN
The aim of this research is to study and diagnose for the first time the Polaroid emulsion transfer in the contemporary artist Paolo Gioli's artworks to provide preliminary knowledge about the materials of his artworks and the appropriate protocols which can be applied for future studies. The spectral analysis performed followed a multi-technical approach first on the mock-up samples created following Gioli's technique and on one original artwork of Gioli, composed by: FORS (Fiber Optics Reflectance), Raman, and FTIR (Fourier-Transform InfraRed) spectroscopies. These techniques were chosen according to their completely non-invasiveness and no requirement for sample collection. The obtained spectra from FTIR were not sufficient to assign the dyes found in the transferred Polaroid emulsion. However, they provided significant information about the cellulose-based materials. The most diagnostic results were obtained from FORS for the determination of the dye developers present in the mock-up sample which was obtained from Polacolor Type 88 and from Paolo Gioli's original artwork created with Polacolor type 89.
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Colorantes , Fotograbar , Emulsiones , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Colorantes/análisis , CelulosaRESUMEN
In recent years, increased use of ammunition without lead and heavy metals was observed, leading to a growing interest in the detection of organic gunshot residues (OGSR) as evidence of firearms related crimes. The wide range of compounds belonging to the OGSR class hinders their mass spectrometric detection as different ionization techniques may be needed to obtain good results for all compounds. The purpose of this work was the development of a reliable analytical method by means of UHPLC-HRMS for the determination in oral fluid (OF) of the most common explosives and the most used stabilizers, arising from fire discharge and post-deflagration residues. For this purpose, SPE was used for OF clean-up before UHPLC-HRMS analysis. All target analytes were chromatographically separated by means of a Polar-C18 column. A chlorinated compound was added to the mobile phases in order to promote the formation of chloride adduct ions in the electrospray ion source operating in polarity switching to allow the best conditions for each analyte. The detection was conducted by means of a high-resolution mass spectrometer equipped with Orbitrap technology working in data dependent acquisition mode, in order to detect both the precursor ions and/or the most intense fragments for stabilizers. To verify its potential, the method was tested on real samples: a shooting session was performed in an open shooting range; the shooters fired from 2 to 20 rounds with a 9x21 caliber, thereafter OF was sampled. Samples were analyzed confirming that explosives may be detected in OF; the use of this matrix may be of great interest for investigative purposes as it is less affected by secondary transfer when compared to other commonly sampled matrices. The developed method could be a useful tool for law enforcement authorities for the detection of explosives in forensic potential scenarios, including biological matrices.
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Sustancias Explosivas , Armas de Fuego , Cloruros , Cromatografía Líquida de Alta Presión/métodos , Medicina Legal/métodos , Espectrometría de Masas/métodosRESUMEN
The cleaning of buildings, statues, and artworks composed of stone materials from metal corrosion is an important topic in the cultural heritage field. In this work the cleaning effectiveness of a PVA-PEO-borax hydrogel in removing metal corrosion products from different porosity stones has been assessed by using a multidisciplinary and non-destructive approach based on relaxation times measurement by single-sided portable Nuclear Magnetic Resonance (NMR), Scanning Electron Microscopy-Energy Dispersive Spectroscopy (SEM-EDS), and Raman Spectroscopy. To this end, samples of two lithotypes, Travertine and Carrara marble, have been soiled by triggering acidic corrosion of some copper coins in contact with the stone surface. Then, a PVA-PEO-borax hydrogel was used to clean the stone surface. NMR data were collected in untreated, soiled with corrosion products, and hydrogel-cleaned samples. Raman spectroscopy was performed on PVA-PEO-borax hydrogel before and after cleaning of metal corrosion. Furthermore, the characterization of the dirty gel was obtained by SEM-EDS. The combination of NMR, SEM-EDS and Raman results suggests that the mechanism behind the hydrogel cleaning action is to trap heavy metal corrosion products, such as Cu2+ between adjacent boron ions cross-linked with PVA. Moreover, the PVA-PEO-borax hydrogel cleaning effectiveness depends on the stone porosity, being better in Carrara marble compared to Travertine.
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Fentanyl and fentalogs' intake as drugs of abuse is experiencing a great increase in recent years. For this reason, there are more and more cases in which it is important to recognize and quantify these molecules and related metabolites in biological matrices. Oral fluid (OF) is often used to find out if a subject has recently used a psychoactive substance and if, therefore, the person is still under the effect of psychotropics. Given its difficulty in handling, good sample preparation and the development of instrumental methods for analysis are essential. In this work, an analytical method is proposed for the simultaneous determination of 25 analytes, including fentanyl, several derivatives and metabolites. OF was collected by means of passive drool; sample pretreatment was developed in order to be fast, simple and possibly semi-automated by exploiting microextraction on packed sorbent (MEPS). The analysis was performed by means of LC-HRMS/MS obtaining good identification and quantification of all the analytes in less than 10 min. The proposed method was fully validated according to the Scientific Working Group for Forensic Toxicology (SWGTOX) international guidelines. Good results were obtained in terms of recoveries, matrix effect and sensitivity, showing that this method could represent a useful tool in forensic toxicology. The presented method was successfully applied to the analysis of proficiency test samples.
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Cromatografía Liquida/métodos , Fentanilo/análisis , Fentanilo/metabolismo , Espectrometría de Masas/métodos , Saliva/metabolismo , Microextracción en Fase Sólida/métodos , Adulto , Femenino , Voluntarios Sanos , Humanos , Límite de Detección , Masculino , Persona de Mediana Edad , Narcóticos/análisis , Narcóticos/metabolismo , Adulto JovenRESUMEN
In the present work, dispersive liquid-liquid microextraction (DLLME) was used to extract six synthetic cannabinoids (JWH-018, JWH-019, JWH-073, JWH-200, or WIN 55,225, JWH-250, and AM-694) from oral fluids. A rapid baseline separation of the analytes was achieved on a bidentate octadecyl silica hydride phase (Cogent Bidentate C18; 4.6 mm × 250 mm, 4 µm) maintained at 37 °C, by eluting in isocratic conditions (water:acetonitrile (25:75, V/V)). Detection was performed using positive electrospray ionization-tandem mass spectrometry. The parameters affecting DLLME (pH and ionic strength of the aqueous phase, type and volume of the extractant and dispersive solvent, vortex and centrifugation time) were optimized for maximizing yields. In particular, using 0.5 mL of oral fluid, acetonitrile (1 mL), was identified as the best option, both as a solvent to precipitate proteins and as a dispersing solvent in the DLLME procedure. To select an extraction solvent, a low transition temperature mixture (LTTM; composed of sesamol and chlorine chloride with a molar ratio of 1:3) and dichloromethane were compared; the latter (100 µL) was proved to be a better extractant, with recoveries ranging from 73% to 101 % by vortexing for 2 min. The method was validated according to the guidelines of Food and Drug Administration bioanalytical methods: intra-day and inter-day precisions ranged between 4 % and 18 % depending on the spike level and analyte; limits of detection spanned from 2 to 18 ng/mL; matrix-matched calibration curves were characterized by determination coefficients greater than 0.9914. Finally, the extraction procedure was compared with previous methods and with innovative techniques, presenting superior reliability, rapidity, simplicity, inexpensiveness, and efficiency.
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The measurement of ethyl glucuronide (EtG) in hair is an established practice to evaluate alcohol consumption habits of the donors; nevertheless, analytical variability has shown to be an important factor to be considered: measured EtG values can vary significantly as a consequence of analyte washout during decontamination, pulverization of samples, extraction solvent and incubation temperature. In the present study, we described a new method for automated hair decontamination and EtG extraction from the inner core of the hair by using pressurized liquid extraction (PLE), followed by solid-phase extraction (SPE) cleanup; validation was performed according to SWGTOX guidelines. The extraction efficiency of the new method was evaluated by comparing the results with those obtained by a validated and ISO/IEC 17025:2005 accredited method; an average positive difference of + 32% was observed when the extraction was performed by PLE. The effect of hair pulverization was also studied, and a good correlation between cut and milled hair was observed, implying that PLE allowed a highly efficient extraction of EtG from the inner keratin core of the hair, no matter if it has been cut or pulverized. Finally, to verify the results, paired aliquots of 27 real hair samples were analyzed with both PLE and a protocol optimized by design-of-experiment strategies planned to maximize the extraction yield; in this case, a comparable efficiency was observed, suggesting that exhaustive EtG extraction was obtained with both approaches. This finding opens new perspectives in the eligible protocols devoted to hair EtG analysis, in terms of speed, automation and reproducibility.
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Alcoholismo , Espectrometría de Masas en Tándem , Consumo de Bebidas Alcohólicas , Biomarcadores , Cromatografía Liquida , Glucuronatos , Humanos , Reproducibilidad de los Resultados , Detección de Abuso de SustanciasRESUMEN
In the present work,dispersive liquid-liquid microextraction (DLLME) was used to extract six synthetic cannabinoids (JWH-018,JWH-019,JWH-073,JWH-200,or WIN 55,225,JWH-250,and AM-694) from oral fluids.A rapid baseline separation of the analytes was achieved on a bidentate octadecyl silica hydride phase (Cogent Bidentate C18;4.6 mm × 250 mm,4 μm) maintained at 37℃,by eluting in isocratic conditions (water:acetonitrile (25:75,V/V)).Detection was performed using positive electrospray ionization-tandem mass spectrometry.The parameters affecting DLLME (pH and ionic strength of the aqueous phase,type and volume of the extractant and dispersive solvent,vortex and centrifugation time)were optimized for maximizing yields.In particular,using 0.5 mL of oral fluid,acetonitrile (1 mL),was identified as the best option,both as a solvent to precipitate proteins and as a dispersing solvent in the DLLME procedure.To select an extraction solvent,a low transition temperature mixture (LTTM;composed of sesamol and chlorine chloride with a molar ratio of 1:3) and dichloromethane were compared;the latter (100 μL) was proved to be a better extractant,with recoveries ranging from 73% to 101% by vortexing for 2 min.The method was validated according to the guidelines of Food and Drug Administration bioanalytical methods:intra-day and inter-day precisions ranged between 4 % and 18 %depending on the spike level and analyte;limits of detection spanned from 2 to 18 ng/mL;matrix-matched calibration curves were characterized by determination coefficients greater than 0.9914.Finally,the extraction procedure was compared with previous methods and with innovative techniques,presenting superior reliability,rapidity,simplicity,inexpensiveness,and efficiency.
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Vesuvius eruption that destroyed Pompeii in AD 79 represents one of the most important events in history. The cataclysm left behind an abundance of archeological evidence representing a fundamental source of the knowledge we have about ancient Roman material culture and technology. A great number of textiles have been preserved, rarely maintaining traces of their original color, since they are mainly in the mineralized and carbonized state. However, one outstanding textile sample displays a brilliant purple color and traces of gold strips. Since the purple was one of the most exclusive dyes in antiquity, its presence in an important commercial site like Pompeii induces us to deepen the knowledge of such artifacts and provide further information on their history. For this reason, the characterization of the purple color was the main scope of this research, and to deepen the knowledge of such artifacts, the SERS (Surface Enhanced Raman Scattering) in solution approach was applied. Then, these data were enriched by HPLC-HRMS analyses, which confirmed SERS-based hypotheses and also allowed to hypothesize the species of the origin mollusk. In this context, a step-by-step integrated approach resulted fundamental to maximize the information content and to provide new data on textile manufacturing and trade in antiquity.
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Productos Biológicos/química , Colorantes/química , Minerales/química , Textiles/análisis , Productos Biológicos/análisis , Cromatografía Líquida de Alta Presión , Colorantes/análisis , Microscopía , Minerales/análisis , Espectrometría RamanRESUMEN
In this work the results deriving from the characterization of materials used by Lucio Fontana to realize some of his artworks are presented. Specifically, object of analyses are three artworks from the collection of National Gallery of Modern and Contemporary Art in Rome, whose complex composition required the combination of different diagnostic techniques for a complete characterization. Microscopic fragments from the artworks were analyzed through X-Ray Fluorescence (XRF), Fourier Transformed InfraRed (FTIR) spectroscopy, in transmission and in Attenuated Total Reflectance (ATR) mode, and Raman spectroscopy to obtain information on the atomic and molecular species and to individuate pigments and binders. In one case, the richness in different materials and the not homogenous distribution on the artwork surface required the additional use of portable techniques, as Visible Light Reflectance and Raman spectroscopies with optical fiber probes, to map the surface. The combination of these techniques resulted to be a powerful tool in order to obtain a complete characterization of artist's choices and provided new information to understand the evolution of his technique.
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OBJECTIVES: Recent studies have suggested that vitamin K may exert significant effects on the central nervous system. The present study investigates the relationship between vitamin K plasmatic levels and cognitive functions in elderly patients on oral anticoagulant therapy (OAT). DESIGN: At the Thrombosis Centre of Haematology, "Sapienza" University of Rome, 85 patients on OAT, aged between 75 and 92, were randomly enrolled in the study. Patients were on OAT with vitamin K antagonists (VKAs). Vitamin K1 concentrations were determined using standardized High-Performance Liquid Chromatography (HPLC). Cognitive functions were assessed using the Milan Overall Dementia Assessment (MODA). RESULTS: MODA scores are positively correlated to vitamin K1 concentration. Patients with vitamin K1 below 0.100 µg/L and between 0.100 and 0.400 µg/L and between 0.100 and 0.400 µg/L and between 0.100 and 0.400 p < 0.001). Even long-term OAT (>10 years) does not affect MODA scores. Education seems to exert a greater role on the cognitive status in comparison with aging. CONCLUSIONS: The study shows a positive association between vitamin K1 concentration and cognitive status in elderly patients (≥75 years) on OAT. The relationship between vitamin K1 concentration and MODA scores is described by a linear model. Cognitive status is not influenced by the duration of OAT but by the years of education.
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Paints used in street art are modern materials subjected to degradation processes, which are very complex and difficult to predict without taking into account of several factors. This study investigates three outdoor murals in Lazio, - namely "graffiti", a word now used to indicate a spontaneous street art tendency consisting in images and writings realized by spray paints in public spaces to provoke passersby -with the aim to discover materials application techniques and chemical composition and figure out whether alteration phenomena occurred. Twenty-two samples were collected, and their stratigraphy was studied by optical microscopy. Fourier Transformed Infrared spectroscopy was used to identify binders and their degradation products in paints and preparatory layers, while for characterization of organic pigments used in all different stratigraphy layers of samples micro-Raman spectroscopy analyses was carried out. Furthermore, micro-Raman spectroscopy allowed to study an unusual patina formed on the surface of a pink paint. This information is useful for artists as well as for conservators, who must face numerous issues related to the preservation of this modern and labile kind of artistic expression, very fashionable nowadays but often created without care for materials duration. Conservation issues were also deepened by interviews with several contemporary mural authors. Artists underlined how contemporary murals are a very heterogeneous means of expression. Different cultural tendencies coexisting result in different attitude towards conservation.
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This paper illustrates the development of a procedure based on the use of a low transition temperature mixture (LTTM) for the dispersive liquid-liquid microextraction (DLLME) of fungicides, insecticides and acaricides from surface waters. The LTTM preparation involves the heat-mixing of choline chloride and acetylsalicylic acid in a molar ratio 1:2 (ChCl(ASA)2). The resulting mixture appears as a clear viscous liquid at room-temperature, denser than water (1.20⯱â¯0.01â¯g mL-1). For its characterization, differential scanning calorimetry (DSC) provided crucial evidence to classify it as a LTTM rather than as a deep eutectic solvent (DES) since it revealed an intense glass transition at -37⯰C. Large-angle X-ray scattering (LAXS) confirmed the lack of any long-distance order. Due to the LTTM immiscibility with water, an evaluation study was carried out to test ChCl(ASA)2 as an effective alternative to the conventional chlorinated solvents for DLLME. To this end, 24 pesticides were used as model compounds, extracted from surface water samples (5â¯mL) and analyzed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The definitive procedure required the optimization of some key parameters such as volume of extracting solvent, type and volume of dispersing solvent, volume of the aqueous sample, LTTM dispersion procedure, and extraction time. Depending on pKa and logP values, recoveries ranged from 18 (for very polar compounds) to 96%, revealing that the ideal candidates for the extraction with ChCl(ASA)2 are neutral compounds with logP >2. After complete validation, the method was applied to analyze water samples from the River Tiber where dodine and dimetomorph were found at low µg L-1 concentration levels.
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Monitoreo del Ambiente/métodos , Microextracción en Fase Líquida , Plaguicidas/aislamiento & purificación , Temperatura de Transición , Contaminantes Químicos del Agua/aislamiento & purificación , Agua/química , Cromatografía Líquida de Alta Presión , Hormonas Juveniles , Plaguicidas/análisis , Solventes/química , Espectrometría de Masas en Tándem , Contaminantes Químicos del Agua/análisisRESUMEN
The increasing phenomenon of drug addiction and the introduction of New Psychoactive Substances (NPS) have led to a progressive growth of research in the field of forensic analytical toxicology, with the need to develop modern and faster analytical procedures. Hair testing has gained increasing attention and recognition as a complement to blood and urine analysis, since it is a unique material for the retrospective detection of drugs, due to its large detection window. In this paper, a multiclass method for the simultaneous extraction, identification and quantification of sixty drugs of abuse belonging to different chemical classes in hair is proposed. This method can provide a valid, fast, simple and low-cost alternative to common tests; at the same time, it provides quantitative results, to concurrently confirm the assumption of one or more illicit substances. Both the decontamination step and the extraction of the analytes from the inner core of the hair were carried out by means of pressurized liquid extraction (PLE) while the clean-up was performed by dispersive liquid/liquid microextraction (dLLME), giving the great advantage of a high enrichment factor. The selected chromatographic conditions allowed a satisfying separation of the 60 analytes in 14â¯min, while the detection was conducted with a high-resolution mass spectrometer with Orbitrap technology. This multiclass method was suitable for analytes with different chemical characteristics allowing to reduce time and cost of analysis, organic solvent volume and the amount of sample required for analysis. The whole method was fully validated as confirmatory method following SWGTOX guidelines.
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Toxicología Forense/métodos , Cabello/química , Drogas Ilícitas/análisis , Microextracción en Fase Líquida , Detección de Abuso de Sustancias/métodos , Cromatografía Líquida de Alta Presión , Humanos , Límite de Detección , Espectrometría de Masas , Estudios Retrospectivos , Solventes/análisis , UrinálisisRESUMEN
The Privilegium maius is one of the most famous and spectacular forgeries in medieval Europe. It is a set of charters made in the 14th century upon commitment by Duke Rudolf IV, a member of the Habsburg family, to elevate the rank and the prestige of his family. These five charters, now kept at the Österreichisches Staatsarchiv in Vienna, have been subjected to a thorough interdisciplinary study in order to shed light on its controversial story. The charters are composed of pergamenaceous documents bound to wax seals with coloured textile threads. The present contribution concerns the characterisation of the inks used for writing and of the dyes used to colour to the threads: Are they compatible with the presumed age of the charters? Though showing only a part of the whole story of the charters, dyes analysis could contribute in assessing their complex history from manufacturing to nowadays. The dyes were characterised with non-invasive in situ measurements by means of fibre optic (FORS) and with micro-invasive measurements by means of Surface Enhanced Raman Spectroscopy (SERS) and High-Performance Liquid Chromatography with Mass Spectrometry (HPLC-MS) analysis. The results showed that the threads of four of the charters (three dyed with madder, one with orchil) were apparently coloured at different dyeing stages, then re-dyed in the 19-20th century.