Hyperspectral imaging in forensic science: An overview of major application areas.

Analysis of evidence is a challenge. Crime scene materials are complex, diverse, sometimes of an unknown nature. Forensic science provides the most critical applications for their examination. Chemical tests, analytical methods, and techniques to process the evidence must be carefully selected by the forensic scientist. Ideally, it may be interpreted, analyzed, and judged in the original context of the crime scene. In this sense, hyperspectral imaging (HSI) has been employed as an analytical tool that maintains the integrity of the samples/objects for multiple and sequential analysis and for counter-proof exams. This paper is an overview of forensic science trends for the application of HSI techniques in the last ten years (2011-2021). The examination of documents was the main area of exploration, followed by bloodstain analysis aging process; trace analysis of explosives and gunshot residue. Chemometric tools were also addressed since they are crucial to obtain the most important information from the samples. There are great challenges in applying HSI in forensic science, but there have been clear technological and scientific advances, and a solid foundation has been built for the use of HSI in real-life cases.

Identifying the most relevant tablet regions in the image detection of counterfeit medicines.

This paper proposes a novel image-based approach to detect counterfeit medicines and identify the most relevant regions of the tablet in the task of classification. Images of medicine tablets undergo an initial pre-processing step which (i) removes the background to find the region of interest, (ii) clusters individual pixels into super-pixels, and (iii) extracts features containing color and texture information. The classification relying on Support Vector Machine (SVM) defines the class the respective image will be inserted into. The task of identifying the relevant regions of the tablets for counterfeiting detection is performed using the concept of support vectors, generating a heat map that indicates the regions that contribute the most to the classification purpose. Two datasets containing images of authentic and counterfeit tablets of Cialis and Viagra were used to validate our propositions, achieving correct classification rates of 100% on both datasets. Regarding the task of identifying the most relevant regions, our proposition outperformed the traditional LIME (Local Interpretable Model-agnostic Explanations) method by yielding more robust explanations.

Preliminary efficiency evaluation of development methods applied to aged sebaceous latent fingermarks.

Latent fingermarks are important trace evidence found in crime scenes mainly used for identification purposes. Once deposited, the composition of samples changes over time influencing the efficacy of latent fingermark development methods. In this sense, the aims of this work were to characterize the fatty acid (FA) profile of sebaceous latent fingermarks by GC-FID and to preliminarily evaluate the development efficiency of enhancement methods (powder dusting, iodine fuming and silver nitrate method) in a 30-day period of aging under controlled parameters of temperature, photoperiod and humidity. Results showed that myristic (7.51 ± 0.76% - 13.39 ± 1.26%), palmitic (35.91 ± 1.07% - 40.81 ± 2.52%), stearic (6.67 ± 0.36% - 9.13 ± 0.36%) and oleic (18.08 ± 0.25% - 20.93 ± 0.26%) acid varied significantly (p < 0.05) over the 30-day period of analysis. Regarding development efficiency, fluorescent orange powder and the silver nitrate method also increased their efficacy to develop latent fingermarks over time while the iodine fuming method decreased its efficiency. Silver black powder had constant efficacy in the tested period. Changes in the constitution of sebaceous marks possibly influenced the development efficiency of enhancement techniques. This knowledge is important to better understand the kinetic of aging and its influence on the development method.

Methodologies Applied to Fingerprint Analysis.

This systematic review deals with the last 10 years of research in analytical methodologies for the analysis of fingerprints, regarding their chemical and biological constituents. A total of 123 manuscripts, which fit the search criteria defined using the descriptor "latent fingermarks analysis," were selected. Its main instrumental areas (mass spectrometry, spectroscopy, and innovative methods) were analyzed and summarized in a specific table, highlighting its main analytical parameters. The results show that most studies in this field use mass spectrometry to identify the constituents of fingerprints, both to determine the chemical profile and for aging. There is also a marked use of mass spectrometry coupled with chromatographic methods, and it provides accurate results for a fatty acid profile. Additional significant results are achieved by spectroscopic methods, mainly Raman and infrared. It is noteworthy that spectroscopic methods using microscopy assist in the accuracy of the analyzed region of the fingerprint, contributing to more robust results. There was also a significant increase in studies using methods focused on finding new developers or identifying components present in fingerprints by rapid tests. This systematic review of analytical techniques applied to the detection of fingerprints explores different approaches to contribute to future studies in forensic identification, verifying new demands in the forensic sciences and assisting in the selection of studies for the progress of research.

Wavenumber selection based on Singular Value Decomposition for sample classification.

The dissemination of falsified medicines is a public health risk. Techniques such as attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy are commonly adopted for fraudulent drug detection. However, the spectrum generated by the ATR-FTIR typically results in hundreds of wavenumbers, reducing the performance of classification methods aimed at discriminating between authentic and falsified medicines. This article proposes a novel method for selecting a reduced size subset of wavenumbers that improves the classifier performance. The singular value decomposition SVD is used to generate a wavenumber importance index. An iterative process creates k-nearest neighbor (KNN) models by adding the wavenumbers in a decreasing order according to the importance index. Wavenumbers that increase classification accuracy are selected. When applied to Cialis® ATR-FTIR data, the proposed approach retained average 0.51% of the original wavenumbers with 100% accurate classifications; as for the Viagra® data set, the method yielded perfect classifications retaining average 0.17% of the original wavenumbers.

Enhancing counterfeit and illicit medicines grouping via feature selection and X-ray fluorescence spectrometry.

In this paper, we propose a novel framework to select the most relevant X-Ray Fluorescence (XRF) energy values (i.e., features) to enhance the clustering (grouping) of counterfeit and illicit medical tablets. The framework is based on the integration of multidimensional scaling (MDS) and Procrustes analysis (PA) multivariate techniques. MDS provides a projection of the original data into a lower dimension, while PA finds a projection matrix from the original data. Such outputs give rise to a feature importance index that guides an iterative feature selection process; after each feature is inserted in the subset, an optimization procedure based on a greedy search method is carried out to maximize the clustering quality assessed through the Silhouette Index (SI). The inorganic chemical fingerprinting of 41 commercial samples (Viagra®, Cialis®, Lazar®, Libiden®, Maxfil®, Plenovit®, Potent 75®, Rigix®, V-50®, Vimax® and Pramil®) and 56 seized counterfeit samples (Viagra and Cialis) was used to validate the proposed framework. From the original 2048 data points in the full spectra, we identified a subset comprised of 41 energy values that substantially improved clustering quality; the obtained groups were assessed by visual inspection of the PCA plots.

Comparison between counterfeit and authentic medicines: A novel approach using differential scanning calorimetry and hierarchical cluster analysis.

Erectile dysfunction medicines such as Cialis and Viagra are very popular worldwide and are between the most prevalent counterfeit medicines in Brazil. A range of analytical methods has been used to analyze Cialis and Viagra, such as ATR-FTIR, GCMS and UPLC-MS. Until now, there are no data available of DSC methods for analysis of counterfeit medicines of Cialis and Viagra. DSC is a thermal analysis that provides useful information of physico-chemical events, and however is almost not used for forensic purposes. In this study, thermal analysis of 25 counterfeit Viagra and Cialis seized by Brazilian Federal Police were performed by DSC and compared to their authentic medicines and analytical standards, along with chemometric tools. Authentic samples of Viagra displayed a similar thermal profile with the API, while Cialis were different with additional endothermic peaks, that could be related to excipients interference. Thermograms of Viagra counterfeit samples were similar to authentic samples, while Cialis showed an enlargement and displacement of endothermic peaks. Also, some Cialis counterfeit samples showed melting peaks attributed to sildenafil, the API of Viagra, instead tadalafil, confirming previous results obtained by UPLC-MS. Multivariate analysis with application of Hierarchical Cluster Analysis classified different groups of samples, including a cluster with counterfeit Cialis and Viagra, indicating the use of same API for both counterfeit medicines and possibly the same illicit production; and a cluster with authentic Viagra and counterfeit Cialis, confirming the addition of sildenafil instead tadalafil to Cialis counterfeit samples. Here for the first time we described the use of DSC for chemical profiling of Cialis and Viagra and showed that even when applied to a small group of samples, DSC along with chemometric tools can be considered as a good auxiliary method in forensic casework samples. DSC provided useful data to perform the identification of counterfeit and authentic medicines, with low cost and a simple method.

Citrus essential oils inhalation by mice: Behavioral testing, GCMS plasma analysis, corticosterone, and melatonin levels evaluation.

The use of orange essential oils (EOs) as a complementary treatment is very common in Brazilian popular culture. The levels of melatonin (MEL) and corticosterone (CORT) hormones were investigated simultaneously, by the Luminex™ immunoassay system in mice plasma, after Citrus aurantium and Citrus sinensis EOs inhalation for 30 min. The plasma was analyzed by headspace through gas chromatography coupled to mass spectrometry for investigation of the EO components. Mice were submitted to behavioral testing to research anxiolytic-like, sedative, and antidepressant-like effects. The inhalation of atmosphere obtained from vaporization of 10% solution of this Citrus EO separately did not affect MEL or CORT plasma levels; that is, the MEL and CORT levels did not present variation in function of the EO in the schedule used. On the other hand, the imipramine positive control used altered the level of MEL as expected. The EO constituents were detected in plasma at different ratios that is present in inhaled EO. Behavioral tests showed that the inhalation of 10% C. sinensis EO presents an anxiolytic-like and sedative effect. Thus, C. sinensis EO can be a valuable tool for treatment of the anxiety disturbs, apparently without interference with MEL and CORT physiological levels.

Near infrared spectroscopy combined with chemometrics for growth stage classification of cannabis cultivated in a greenhouse from seized seeds.

Cannabis sativa L. (cannabis, Cannabaceae), popularly called marijuana, is one of the oldest plants known to man and it is the illicit drug most used worldwide. It also has been the subject of increasing discussions from the scientific and political points of view due to its medicinal properties. In recent years in Brazil, the form of cannabis drug trafficking has been changing and the Brazilian Federal Police has exponentially increased the number of seizures of cannabis seeds sent by the mail. This new form of trafficking encouraged the study of cannabis seeds seized germinated in a greenhouse through NIR spectroscopy combined with chemometrics. The plants were cultivated in a homemade greenhouse under controlled conditions. In three different growth periods (5.5weeks, 7.5weeks and 10weeks), they were harvested, dried, ground and directly analyzed. The iPCA was used to select the best NIR spectral range (4000-4375cm-1) in order to develop unsupervised and supervised methods. The PCA and HCA showed a good separation between the three groups of cannabis samples at different growth stages. The PLS-DA and SVM-DA classified the samples with good results in terms of sensitivity and specificity. The sensitivity and specificity for SVM-DA classification were equal to unity. This separation may be due to the correlation of cannabinoids and volatile compounds concentration during the growth of the cannabis plant. Therefore, the growth stage of cannabis can be predicted by NIR spectroscopy and chemometric tools in the early stages of indoor cannabis cultivation.

A genetic algorithm-based framework for wavelength selection on sample categorization.

In forensic and pharmaceutical scenarios, the application of chemometrics and optimization techniques has unveiled common and peculiar features of seized medicine and drug samples, helping investigative forces to track illegal operations. This paper proposes a novel framework aimed at identifying relevant subsets of attenuated total reflectance Fourier transform infrared (ATR-FTIR) wavelengths for classifying samples into two classes, for example authentic or forged categories in case of medicines, or salt or base form in cocaine analysis. In the first step of the framework, the ATR-FTIR spectra were partitioned into equidistant intervals and the k-nearest neighbour (KNN) classification technique was applied to each interval to insert samples into proper classes. In the next step, selected intervals were refined through the genetic algorithm (GA) by identifying a limited number of wavelengths from the intervals previously selected aimed at maximizing classification accuracy. When applied to Cialis®, Viagra®, and cocaine ATR-FTIR datasets, the proposed method substantially decreased the number of wavelengths needed to categorize, and increased the classification accuracy. From a practical perspective, the proposed method provides investigative forces with valuable information towards monitoring illegal production of drugs and medicines. In addition, focusing on a reduced subset of wavelengths allows the development of portable devices capable of testing the authenticity of samples during police checking events, avoiding the need for later laboratorial analyses and reducing equipment expenses. Theoretically, the proposed GA-based approach yields more refined solutions than the current methods relying on interval approaches, which tend to insert irrelevant wavelengths in the retained intervals. Copyright © 2016 John Wiley & Sons, Ltd.

Seized cannabis seeds cultivated in greenhouse: A chemical study by gas chromatography-mass spectrometry and chemometric analysis.

Cannabis sativa L. is cultivated in most regions of the world. In 2013, the Brazilian Federal Police (BFP) reported 220 tons of marijuana seized and about 800,000 cannabis plants eradicated. Efforts to eradicate cannabis production may have contributed to the development of a new form of international drug trafficking in Brazil: the sending of cannabis seeds in small amounts to urban centers by logistics postal. This new and increasing panorama of cannabis trafficking in Brazil, encouraged the chemical study of cannabis seeds cultivated in greenhouses by gas-chromatography coupled with mass spectrometry (GC-MS) associated with exploratory and discriminant analysis. Fifty cannabis seeds of different varieties and brands, seized by the BFP were cultivated under predefined conditions for a period of 4.5 weeks, 5.5 weeks, 7.5 weeks, 10 weeks and 12 weeks. Aerial parts were analyzed and cannabigerol, cannabinol, cannabidiol, cannabichromene Δ9-tetrahydrocannabinol (THC) and other terpenoids were detected. The chromatographic chemical profiles of the samples were significantly different, probably due to different variety, light exposition and age. THC content increased with the age of the plant, however, for other cannabinoids, this correlation was not observed. The chromatograms were plotted in a matrix with 50 rows (samples) and 3886 columns (abundance in a retention time) and submitted to PCA, HCA and PLS-DA after pretreatment (normalization, first derivative and autoscale). The PCA and HCA showed age separation between samples however it was not possible to verify the separation by varieties and brands. The PLS-DA classification provides a satisfactory prediction of plant age.

Gender differences in biochemical markers and oxidative stress of rats after 28 days oral exposure to a mixture used for weight loss containing p-synephrine, ephedrine, salicin, and caffeine

ABSTRACT The association of p-synephrine, ephedrine, salicin, and caffeine in dietary supplements and weight loss products is very common worldwide, even though ephedrine has been prohibited in many countries. The aim of this study was to evaluate a 28-day oral exposure toxicity profile of p-synephrine, ephedrine, salicin, and caffeine mixture (10:4:6:80 w/w respectively) in male and female Wistar rats. Body weight and signs of toxicity, morbidity, and mortality were observed daily. After 28 days, animals were euthanized and blood collected for hematological, biochemical, and oxidative stress evaluation. No clinical signs of toxicity, significant weight loss or deaths occurred, nor were there any significant alterations in hematological parameters. Biochemical and oxidative stress biomarkers showed lipid peroxidation, and hepatic and renal damage (p < 0.05; ANOVA/Bonferroni) in male rats (100 and 150 mg/kg) and a reduction (p < 0.05; ANOVA/Bonferroni) in glutathione (GSH) levels in all male groups. Female groups displayed no indications of oxidative stress or biochemical alterations. The different toxicity profile displayed by male and female rats suggests a hormonal influence on mixture effects. Results demonstrated that the tested mixture can alter oxidative status and promote renal and hepatic damages.

RESUMO A associação de p-sinefrina, efedrina, salicina, e cafeína em suplementos alimentares e produtos para perda de peso é muito utilizada em todo o mundo, embora a efedrina tenha sido proibida em muitos países. O objetivo deste estudo foi avaliar o perfil de toxicidade à exposição oral de 28 dias à associação de p-sinefrina, efedrina, salicina e cafeína (na proporção de 10:4:6:80 m/m respectivamente) em ratos Wistar machos e fêmeas. Diariamente, os animais foram observados quanto ao peso corporal, sinais de toxicidade, morbidade e mortalidade. Após 28 dias, os animais foram sacrificados e o sangue coletado para avaliações hematológicas, bioquímicas e de estresse oxidativo. Não se observaram sinais clínicos de toxicidade, tampouco perda significativa de peso, mortes, ou quaisquer alterações significativas nos parâmetros hematológicos. Biomarcadores do estresse oxidativo e bioquímicos mostraram peroxidação lipídica, danos renais e hepáticos (p < 0,05; ANOVA/Bonferroni) em ratos machos (100 e 150 mg/kg) e a redução (p < 0,05; ANOVA/Bonferroni) nos níveis de glutationa reduzida (GSH) em todos os grupos de machos tratados. Nas fêmeas, não houve indícios de estresse oxidativo, nem alterações bioquímicas. O diferente perfil de toxicidade entre os gêneros sugere influência hormonal nos efeitos de mistura administrada. A associação testada pode alterar o estado oxidativo e promover danos renais e hepáticos.

Selecting relevant Fourier transform infrared spectroscopy wavenumbers for clustering authentic and counterfeit drug samples.

This paper proposes a novel method for selecting subsets of wavenumbers provided by attenuated total reflectance by Fourier transform infrared (ATR-FTIR) spectroscopy able to improve the clustering of medicine samples into two groups; i.e., authentic or fraudulent. For that matter, we apply principal components analysis (PCA) to ATR-FTIR data, and derive two variable importance indices from the PCA parameters. Next, an iterative variable (i.e. wavenumbers) elimination procedure and sample clustering through k-means and Fuzzy C-means techniques are carried out; clustering performance is assessed by the Silhouette Index (SI). The performance of the proposed method is compared with a greedy variable selection method, the "leave one variable out at a time" approach, in terms of clustering quality, percent of retained variables, and computational time. When applied to Viagra ATR-FTIR data, our propositions increased the average SI from 0.5307 to 0.8603 using 0.61% of the original 661 wavenumbers; as for Cialis ATR-FTIR data, clustering quality increased from 0.7548 to 0.8681 when 1.21% of the original wavenumbers were retained in the procedure. The retained wavenumbers, located in the 1091-1046cm(-1) region, comprise the lactose typically hailed as key substance to discriminate between authentic and counterfeit samples.

PLS-DA wavenumber selection for the categorization of medicine samples based on multiple criteria.

ATR-FTIR spectra may include a large number of noisy and correlated wavenumbers that tend to affect and reduce the performance of exploratory and classificatory multivariate techniques. We propose a method based on Partial Least Square Discriminant Analysis (PLS-DA) for identifying the relevant subsets of ATR-FTIR wavenumbers aimed at classifying Viagra and Cialis into authentic or fraudulent categories. In our propositions, the PLS-DA is applied to ATR-FTIR data, and four indices aimed at evaluating wavenumber importance are derived from PLS-DA parameters. Next, an iterative wavenumber elimination and classification procedure integrating PLS-DA and the proposed indices is carried out: the wavenumber with the smallest index is removed, and a new classification is performed using the remaining wavenumbers. The classification performance is assessed through multiple criteria, i.e., sensitivity, specificity and percent of wavenumbers retained; the recommended wavenumber subset is chosen based on the distance between the candidate subsets and a hypothetical ideal solution. The proposed method significantly reduced the percent of wavenumbers to be assessed, and slightly improved classification performance for Viagra and Cialis data when compared to classification on all the original wavenumbers.

Simultaneous analysis of amphetamine-type stimulants in plasma by solid-phase microextraction and gas chromatography-mass spectrometry.

Brazil is considered one of the countries with the highest number of amphetamine-type stimulant (ATS) users worldwide, mainly diethylpropion (DIE) and fenproporex (FEN). The use of ATS is mostly linked to diverted prescription stimulants and this misuse is widely associated with (ab)use by drivers. A validated method was developed for the simultaneous analysis of amphetamine (AMP), DIE and FEN in plasma samples employing direct immersion-solid-phase microextraction, and gas chromatographic/mass spectrometric analysis. Trichloroacetic acid 10% was used for plasma deproteinization. In situ derivatization with propylchloroformate was employed. The linear range of the method covered from 5.0 to 100 ng/mL. The detection limits were 1.0 (AMP), 1.5 (DIE) and 2.0 ng/mL (FEN). The accuracy assessment of the control samples was within 85.58-108.33% of the target plasma concentrations. Recoveries ranged from 46.35 to 84.46% and precision was <15% of the value of relative standard deviation. This method is appropriate for screening and confirmation in plasma forensic toxicology analyses of these basic drugs.

Chemical constituents and pharmacological profile of Gunnera manicata L. extracts

Gunnera perpensa L. (Gunneraceae) is a native South African plant widely used in traditional medicine as an antibacterial and antifungal. In southern Brazil there is the native species called Gunnera manicata L. that also belongs to the Gunneraceae. Nevertheless, there is no information about chemical and pharmacological properties of South American Gunnera species. Therefore this study aimed at assessing the phytochemical and pharmacological profiles of aqueous and methanol Brazilian G. manicata extracts. The results showed that antimicrobial activity in an agar diffusion assay was effective against Staphylococcus aureus and Candida albicans . Phenolic compounds were investigated by liquid chromatography coupled with a tandem mass spectrometer (LC-MS/MS) and all extracts presented gallic acid and only the methanol extract obtained from the leaves exhibited hyperoside. Rutin, quercetin and chlorogenic acid were not found in the samples analysed. Total phenolic content was higher in methanol extract and total flavonoid content was low in all extracts. Antioxidant activity was evaluated by the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical test, and all samples presented good to moderate antioxidant activity. These results encourage complementary studies on the chemical composition of the plant extracts focusing on isolation and structure elucidation of their active compounds.

Gunnera perpensa L. (Gunneraceae) é uma planta nativa do sul da África utilizada na medicina tradicional como antibiótico e antifúngico. Gunnera manicata L. é uma planta nativa do sul do Brasil também da família Gunneraceae e, apesar disso, não há informações sobre suas propriedades químicas e farmacológicas. Assim, o objetivo deste estudo foi avaliar o perfil fitoquímico e farmacológico dos extratos aquoso e metanólico de G. manicata. Os resultados do ensaio microbiológico de difusão em ágar demonstraram que os extratos testados foram ativos contra Staphylococcus aureus e Candida albicans. A presença de compostos fenólicos foi investigada pela técnica de Cromatografia Líquida acoplada a espectrômetro de massas em Tandem (CL-EM/EM). Em todas as amostras analisadas verificou-se a presença de ácido gálico e somente o extrato metanólico das folhas apresentou hiperosídeo. Rutina, quercetina e ácido clorogênico não foram encontrados. O conteúdo total de compostos fenólicos foi maior nos extratos metanólicos e o conteúdo de flavonóides totais foi baixo em todos os extratos. A atividade antioxidante foi avaliada pelo teste da atividade do radical 2,2-diphenyl-1-picril-hidrazil (DPPH) e todas as amostras apresentaram boa a moderada atividade antioxidante. Esses resultados encorajam estudos complementares da composição química dos extratos com foco no isolamento e na elucidação estrutural dos compostos ativos.

A framework for selecting analytical techniques in profiling authentic and counterfeit Viagra and Cialis.

Several analytical techniques aimed at profiling drugs are deemed costly and time consuming, and may not be promptly available for analysis when required. This paper proposes a method for identifying the analytical techniques providing the most relevant data for classification of drug samples into authentic and unauthentic categories. For that matter, we integrate principal components analysis (PCA) to k-Nearest Neighbor (KNN) and Support Vector Machine (SVM) classification tools. PCA is first applied to data from five techniques, i.e., physical profile, X-ray fluorescence (XRF), direct infusion electrospray ionization mass spectrometry (ESI-MS), active pharmacological ingredients profile (ultra performance liquid chromatography, UPLC-MS), and infrared spectroscopic profile (ATR-FTIR). Subsets of PCA scores are then combined with a "leave one subset out at a time" approach, and the classification accuracy using KNN and SVM evaluated after each subset is omitted. Subsets yielding the maximum accuracy indicate the techniques to be prioritized in profiling applications. When applied to data from Viagra and Cialis, the proposed method recommended using the data from UPLC-MS, physical profile and ATR-FTIR techniques, which increased the categorization accuracy. In addition, the SVM classification tool is suggested as more accurate when compared to the KNN.

Profiling counterfeit Cialis, Viagra and analogs by UPLC-MS.

In this work, the chemical profile of 43 commercial samples of tablets for male erectile dysfunction (Viagra, Cialis, Lazar, Libiden, Maxfil, Plenovit, Potent 75, Rigix, Vimax, Pramil 75 and Pramil) and 65 counterfeit samples (Viagra and Cialis) were obtained from UPLC-MS data. Methanol extracts of crushed tablets were investigated by ultra performance liquid chromatography (UPLC) with diode array detection (DAD) coupled with eletrospray ionization in the positive ion mode (ESI(+)) quadrupole time-of-flight (Q-Tof) mass spectrometry (MS). A validated method was employed for the simultaneous determination of sildenafil citrate (SLD) and tadalafil (TAD). The ultra-chromatograms obtained with method provide high resolution of MS, and are a quick (less to 1.5 min) and reliable tool in the distinction between authentic and counterfeit tablets. It was observed in most cases the presence of other active pharmaceutical ingredients (APIs) than specified on the package (TAD and SLD). Additionally, high concentrations of TAD and SLD were detected in counterfeit samples when compare with observed values for a typical commercial product. Chemometric methods were employed and the samples were grouped in five groups as function of API content.

Trends in counterfeits amphetamine-type stimulants after its prohibition in Brazil.

Brazil is one of the world's highest users of anorectic drugs, mainly diethylpropione, fenproporex and sibutramine. The present work focuses on physical and chemical characteristics of 17 counterfeited capsules containing amphetamine-type stimulants (ATS) from three seizures conducted by Brazilian Federal Police. The physical profile was useful in indicating forgery, bring complementary information, but the use of this data singly was not sufficient to distinguish between authentic and counterfeited medicines. The chemical analysis revealed that the seizures capsules labeled as Desobesi-M (fenproporex 25mg), actually contained the active pharmaceutical ingrediente (API) sibutramine. The amount of this API ranged from 1/3 to 2 times the amount of drug found in commercial product, may reach twice the recommended daily dose. Multivariate analysis with application of principal component analysis on data from spectroscopy attenuated total reflectance Fourier transform infrared classified the samples according to their similarities, indicating that two seizures had common origin. This study represents the first step in the elucidation of falsification of ATS in Brazil. Considering the forensic intelligence these information are valuable in order to develop and establish a database that enables correlate samples from different locations and/or suppliers and to map the profile and trends of trafficking.

Counterfeit Cialis and Viagra fingerprinting by ATR-FTIR spectroscopy with chemometry: can the same pharmaceutical powder mixture be used to falsify two medicines?

This paper proposes a direct and efficient method to discriminate between counterfeit and authentic Cialis and Viagra samples by combining attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy with multivariate techniques. The chemical profile of 53 commercial samples (Viagra(®), Cialis(®)) and 104 counterfeit samples (Viagra and Cialis) from distinct seizures were obtained from ATR-FTIR data derived from 10mg of crushed core tablets. Principal component analysis (PCA) technique was employed to classify samples based on the fingerprint region mid-infrared spectra (1800-525 cm(-1)) using OMNIC v.7.2 software; PCA enabled categorizing samples in groups with different chemical profiles, successfully distinguishing between authentic and counterfeits samples in forensic routine. The existence of active pharmaceutical ingredients (API) and technological adjuvant others than specified on the medicine package were also detected in counterfeit samples. In addition, we applied the similarity match (SM) method to demonstrate that a mixture of pharmaceutical powders deriving from a common origin may have been used to manufacture both counterfeit Cialis and Viagra tablets from distinct seizures.