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1.
Cureus ; 16(3): e56489, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38638762

RESUMEN

Foreign body (FB) aspiration is a matter that should not be taken lightly. The presence of a foreign object might lead to hazardous complications, particularly in the pediatric population. These complications depend on the type and location of the aspirated object as the tracheobronchial tree has a very small diameter, and foreign bodies become stuck in the upper airways of children, causing stridor and sudden difficulty in breathing. Impaction of a foreign body in the right bronchial tree is more frequent due to the relatively straighter alignment of the right mainstem of the trachea, as opposed to the left side. Herein, we present a 10-year-old Malay boy who accidentally aspirated a pencil cap. An urgent computed tomography (CT) of the thorax revealed a suspicious intraluminal FB in the bronchus leading to pneumothorax and pneumomediastinum. He underwent a right bronchoscopy and a successful FB removal.

2.
Int J Biol Macromol ; 264(Pt 2): 130682, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38460636

RESUMEN

Tropical fruits, predominantly cultivated in Southeast Asia, are esteemed for their nutritional richness, distinctive taste, aroma, and visual appeal when consumed fresh. However, postharvest challenges have led to substantial global wastage, nearly 50 %. The advent of edible biopolymeric nanoparticles presents a novel solution to preserve the fruits' overall freshness. These nanoparticles, being edible, readily available, biodegradable, antimicrobial, antioxidant, Generally Recognized As Safe (GRAS), and non-toxic, are commonly prepared via ionic gelation owing to the method's physical crosslinking, simplicity, and affordability. The resulting biopolymeric nanoparticles, with or without additives, can be employed in basic formulations or as composite blends with other materials. This study aims to review the capabilities of biopolymeric nanoparticles in enhancing the physical and sensory aspects of tropical fruits, inhibiting microbial growth, and prolonging shelf life. Material selection for formulation is crucial, considering coating materials, the fruit's epidermal properties, internal and external factors. A variety of application techniques are covered such as spraying, and layer-by-layer among others, including their advantages, and disadvantages. Finally, the study addresses safety measures, legislation, current challenges, and industrial perspectives concerning fruit edible coating films.


Asunto(s)
Películas Comestibles , Conservación de Alimentos/métodos , Frutas , Antioxidantes
3.
Int J Mol Sci ; 24(5)2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36902038

RESUMEN

Wounds are considered to be a serious problem that affects the healthcare sector in many countries, primarily due to diabetes and obesity. Wounds become worse because of unhealthy lifestyles and habits. Wound healing is a complicated physiological process that is essential for restoring the epithelial barrier after an injury. Numerous studies have reported that flavonoids possess wound-healing properties due to their well-acclaimed anti-inflammatory, angiogenesis, re-epithelialization, and antioxidant effects. They have been shown to be able to act on the wound-healing process via expression of biomarkers respective to the pathways that mainly include Wnt/ß-catenin, Hippo, Transforming Growth Factor-beta (TGF-ß), Hedgehog, c-Jun N-Terminal Kinase (JNK), NF-E2-related factor 2/antioxidant responsive element (Nrf2/ARE), Nuclear Factor Kappa B (NF-κB), MAPK/ERK, Ras/Raf/MEK/ERK, phosphatidylinositol 3-kinase (PI3K)/Akt, Nitric oxide (NO) pathways, etc. Hence, we have compiled existing evidence on the manipulation of flavonoids towards achieving skin wound healing, together with current limitations and future perspectives in support of these polyphenolic compounds as safe wound-healing agents, in this review.


Asunto(s)
Flavonoides , Fosfatidilinositol 3-Quinasas , Cicatrización de Heridas , Flavonoides/farmacología , FN-kappa B/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal/efectos de los fármacos , Cicatrización de Heridas/efectos de los fármacos , Humanos
4.
J Forensic Sci ; 68(1): 75-85, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36273275

RESUMEN

Drugs-facilitated crimes (DFCs) involve the incapacitation of victims under the influence of drugs. Conventionally, a drug administration act is often determined through the examination of biological samples; however, dry residues from any surface, such as drinking glass if related to a DFC could be a potential source of evidence. This study was aimed to establish an attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy coupled with chemometrics for the determination of spiked sedative-hypnotics from dry residues of a drug-spiked beverage. In this study, four sedative-hypnotics, namely diazepam, ketamine, nimetazepam, and xylazine were examined using ATR-FTIR spectroscopy. Subsequently, the ATR-FTIR profiles were compared and decomposed by principal component analysis (PCA) followed by linear discriminant analysis (LDA) for their detection and discrimination. Visual comparison of ATR-FTIR profiles revealed distinct spectra among the tested drugs. An initial unsupervised exploratory PCA model indicated the separation of four main sedative-hypnotics clusters, and the proposed PCA score-LDA model had allowed for a 100% accurate classification. Discrimination of sedative-hypnotics from a dry beverage previously spiked with these drugs was also possible upon an additional extraction procedure. In conclusion, ATR-FTIR coupled with PCA score-LDA model was useful in detecting and discriminating sedative-hypnotics, including those that had been previously spiked into a beverage.


Asunto(s)
Bebidas , Quimiometría , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Análisis de Fourier , Análisis de Componente Principal , Hipnóticos y Sedantes
5.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-998843

RESUMEN

@#Introduction: Fingermarks left at a crime scene can indicate the presence of an individual and his/her involvement in the crime. Fingermarks, usually invisible, can appear on any surface and may be contaminated by any exogenous substances, including drug substance. Recovery of fingermarks contaminated by drug substance is crucial to link an individual with the drug-related crimes. Hence, this study was aimed to investigate the recovery and visualisation of methamphetamine-contaminated fingermarks from various non-porous surface materials. Methods: In this study, fingermarks were deposited on 11 types of surface materials varied by the presence of methamphetamine contamination, immediacy of deposition, and their concentration levels. Each fingermark was then developed using white and black fingerprint powders, graded, and compared based on the different settings. Results: Application of fingerprint powder was good in developing fingermarks; however, its suitability depends on the nature of the surface materials. Black fingerprint powder produced better visualisation where the fingermarks on all the 11 surface materials tested in this study were successfully recovered compared to white fingerprint powders. Methamphetamine-contaminated fingermarks could still be recovered using the fingerprint powder dusting method, but the fingermark grade was reduced due to the presence of exogenous substance. Conclusion: To conclude, the recovery and visualisation of methamphetamine-contaminated fingermarks on non-porous surfaces were successfully carried out through the application of fingerprint powder. A more severe contamination might lead to lower fingermark grade showing lesser ridge details.

6.
Cureus ; 15(12): e50430, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38222161

RESUMEN

We report two cases of nasal alveolar rhabdomyosarcoma (ARMS) in adult patients from our center who presented with local mass effect and systemic involvement. Our first patient had spontaneous unilateral epistaxis. Her blood investigation showed severe thrombocytopenia, and the bone marrow biopsy result showed bone marrow infiltration by non-hematopoietic malignant cells. Nasal endoscopy showed a mass arising medial to the left middle turbinate. Our second patient presented with right eye proptosis, associated with blurring of vision. Nasal endoscopy showed a right whitish nasal mass arising lateral to the middle turbinate. Both patients were diagnosed by immunohistochemical analysis showing ARMS, a soft tissue malignancy uncommon in adults. RMS in adults has a worse prognosis. Hence, the management is challenging. Early diagnostic workup is essential for the commencement of early treatment for better oncological outcomes.

7.
Cureus ; 15(12): e50411, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38213374

RESUMEN

Oropharyngeal squamous cell carcinoma is a prevalent neoplastic condition. The incidence rate in Malaysia is rising, with human papillomavirus (HPV) infection being recognized as a significant contributing factor. Hence, it is paramount for physicians to effectively diagnose and identify significant indicators that may indicate a malignant etiology. In this study, we present a case of a middle-aged Malay male who presented with the primary symptom of persistent right throat discomfort for one month. The preliminary presentation, blood parameters, and initial histopathological examination (HPE) findings indicate the presence of an infection. However, despite undergoing several medical treatments, the patient's symptoms remain, albeit with only minor clinical improvement. Subsequently, the patient underwent a biopsy under general anesthesia, which subsequently yielded a report indicating the presence of oropharyngeal squamous cell carcinoma with a negative p16 status. Therefore, it is imperative for clinicians to possess knowledge of warning flags and exercise vigilance when encountering a patient who fails to respond despite thorough and precise evaluation. If there is a strong suspicion of malignancy, it is imperative to do a comprehensive clinical investigation and regular monitoring.

8.
PLoS One ; 17(10): e0268756, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36206268

RESUMEN

Ethnicity, native and/or foreign language knowledge, as well as the learned writing systems potentially influence the development of an individual's handwriting. The unique education system consisting of National schools, Chinese-medium vernacular schools, Tamil-medium vernacular schools, and Islamic religious schools in Malaysia may have established specific characteristic handwritten allographic features that deserve investigation within the intelligence context. This study was aimed to explore handwritten allographic features of handwriting samples from 120 subjects (30 writers from four different educational backgrounds mentioned above). Characteristic features which could be attributed to the study groups were statistically analyzed and identified. In this study, thirteen allographic features, including letters "A", "B", "D", "H", "p", "T", "t", "w", "X" and "x", were found to be discriminative. Such information could serve to indicate the primary education system undergone by a writer; enabling the comparison of different handwriting profiles and allowing characterization of writers to a specific group of people.


Asunto(s)
Etnicidad , Escritura Manual , Biometría , Humanos , India , Lenguaje
9.
ACS Omega ; 7(21): 17679-17691, 2022 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-35664606

RESUMEN

Formalin is illegally used as an antibacterial and a preservative in seafood products. It is extremely important for public health reasons to be able to simply, rapidly, and accurately detect formalin in fresh seafood. In this work, we developed a flow injection amperometric (FI-Amp) formalin sensor based on a glassy carbon electrode modified with a composite of palladium particles and carbon microspheres (PdPs-CMs/GCE). The CMs were decorated with PdPs via an electroless deposition method. The surface morphology of the CMs and the PdPs-CMs composite was characterized by scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDX). The electrochemical behavior and measurement of formalin at the PdPs-CMs/GCE was evaluated by cyclic voltammetry and amperometry. The modified electrode demonstrated good electrocatalytic performance for the oxidation of formalin. The synthesis method and FI-Amp operating conditions were optimized. Under the optimal conditions, the developed sensor showed a linear range of 0.025 to 15.00 mmol L-1 and a detection limit of 8 µmol L-1. Repeatability (RSD < 4.1%, n = 30), reproducibility (RSD = 0.25%, n = 5), stability (RSD = 3.2%, n = 80), and selectivity were good. The fabricated sensor achieved recoveries of formalin in seafood between 96 ± 1 to 105 ± 3 (n = 3).

10.
J Forensic Sci ; 67(5): 1836-1845, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35616477

RESUMEN

Presently, investigations of drug-facilitated crimes (DFCs) rely on the detection of substances extracted from biological samples following intake by the victim. However, such detection requires rapid sampling and analysis prior to metabolism and elimination of the drugs from the body. In cases of suspected DFCs, drug-spiked beverage samples, whether in liquid, droplet, or even dried form, can be tested for the presence of spike drugs and used as evidence for the occurrence of DFCs. This study aimed to quantitatively determine three sedative-hypnotics (ketamine, nimetazepam, and xylazine) from drug-spiked beverages using a vortex-assisted dispersive liquid-liquid microextraction-gas chromatography (VADLLME-GC) approach. In this study, a GC method was first developed and validated, followed by the optimization of the VADLLME protocol, which was then applied to quantify the target substances in simulated forensic case scenarios. The developed GC method was selective, sensitive (limit of detection: 0.08 µg/ml [ketamine]; 0.16 µg/ml [nimetazepam]; 0.08 µg/ml [xylazine]), linear (R2 > 0.99), precise (%RSD <7.2%), and accurate (% recovery: 92.8%-103.5%). Higher recoveries were achieved for the three drugs from beverage samples in liquid form (51%-97%) as compared to droplet (48%-96%) and dried (44%-93%) residues. The recovery was not hindered by very low volumes of spiked beverage and dried residues. In conclusion, the developed VADLLME-GC method successfully recovered ketamine, nimetazepam, and xylazine from spiked beverages that are likely to be encountered during forensic investigation of DFCs.


Asunto(s)
Ketamina , Microextracción en Fase Líquida , Bebidas/análisis , Cromatografía de Gases , Ketamina/análisis , Límite de Detección , Microextracción en Fase Líquida/métodos , Nitrazepam/análogos & derivados , Xilazina/análisis
11.
ACS Omega ; 7(16): 13913-13924, 2022 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-35559175

RESUMEN

A portable electrochemical device for xylazine detection is presented for the first time. An electrochemical paper-based analytical device (ePAD) was integrated with a smartphone. The fabrication of the ePAD involved wax printing, low-tack transfer tape, and cutting and screen-printing techniques. Graphene ink was coated on the substrate and modified with nanocoral-like polyaniline, providing an electron transfer medium with a larger effective surface area that promoted charge transfer. The conductive ink on the ePAD presented a thickness of 25.0 ± 0.9 µm for an effective surface area of 0.374 cm2. This sensor was then tested directly on xylazine using differential pulse voltammetry. Two linear responses were obtained: from 0.2 to 5 µg mL-1 and from 5 to 100 µg mL-1. The detection limit was 0.06 µg mL-1. Reproducibility was tested on 10 preparations. The relative standard deviation was less than 5%. The applicability of the sensor was evaluated with beverage samples spiked with trace xylazine. Recoveries ranged from 84 ± 4 to 105 ± 2%. The developed sensor demonstrated excellent accuracy in the detection of trace xylazine. It would be possible to develop the portable system to detect various illicit drugs to aid forensic investigations.

12.
Sensors (Basel) ; 22(8)2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35459019

RESUMEN

Multichannel graphite electrodes (MGrEs) have been designed and fabricated in this study. A template was cut from an adhesive plastic sheet using a desktop cutting device. The template was placed on a polypropylene substrate, and carbon graphite ink was applied with a squeegee to the template. The size of the auxiliary electrode (AE) as well as the location of the reference electrode (RE) of MGrEs design were investigated. Scanning electron microscopy was used to determine the thickness of the ink on the four working electrodes (WEs), which was 21.9 ± 1.8 µm. Cyclic voltammetry with a redox probe solution was used to assess the precision of the four WEs. The intra-electrode repeatability and inter-electrode reproducibility of the MGrEs production were satisfied by low RSD (<6%). Therefore, the MGrEs is reliable and capable of detecting four replicates of the target analyte in a single analysis. The electrochemical performance of four WEs was investigated and compared to one WE. The sensitivity of the MGrEs was comparable to the sensitivity of a single WE. The MGrEs' potential applications were investigated by analyzing the nitrite in milk and tap water samples (recoveries values of 97.6 ± 0.4 to 110 ± 2%).


Asunto(s)
Grafito , Técnicas Electroquímicas/métodos , Electrodos , Límite de Detección , Impresión Tridimensional , Reproducibilidad de los Resultados
13.
J Pharm Pharmacol ; 74(10): 1367-1390, 2022 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-35191505

RESUMEN

OBJECTIVE: Additive manufacturing (AM), commonly known as 3D printing (3DP), has opened new frontiers in pharmaceutical applications. This review is aimed to summarise the recent development of 3D-printed dosage forms, from a pharmacists' perspective. METHODS: Keywords including additive manufacturing, 3D printing and drug delivery were used for literature search in PubMed, Excerpta Medica Database (EMBASE) and Web of Science, to identify articles published in the year 2020. RESULTS: For each 3DP study, the active pharmaceutical ingredients, 3D printers and materials used for the printing were tabulated and discussed. 3DP has found its applications in various dosage forms for oral delivery, transdermal delivery, rectal delivery, vaginal delivery, implant and bone scaffolding. Several topics were discussed in detail, namely patient-specific dosing, customisable drug administration, multidrug approach, varying drug release, compounding pharmacy, regulatory progress and future perspectives. AM is expected to become a common tool in compounding pharmacies to make polypills and personalised medications. CONCLUSION: 3DP is an enabling tool to fabricate dosage forms with intricate structure designs, tailored dosing, drug combinations and controlled release, all of which lend it to be highly conducive to personalisation, thereby revolutionising the future of pharmacy practice.


Asunto(s)
Sistemas de Liberación de Medicamentos , Farmacéuticos , Preparaciones de Acción Retardada , Formas de Dosificación , Liberación de Fármacos , Humanos , Impresión Tridimensional , Tecnología Farmacéutica
14.
Talanta ; 243: 123319, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35220078

RESUMEN

We developed a simple, inexpensive, environmentally friendly one-step fabrication of a flexible laser induced graphene-chitosan-gold nanoparticles (LIG-CS-AuNPs) electrode. The fabrication was based on a laser treatment of polyimide (PI) film coated with CS solution containing gold ions (Au (III)). The AuNPs decorating the induced 3D graphene composite were uniformly distributed. The electrode exhibited good electrical conductivity and excellent electrocatalytic activity toward the oxidation of UA. To enable on-site monitoring of uric acid (UA) in blood serum by differential pulse adsorptive stripping voltammetry (DPAdSV), the electrode was coupled to a portable potentiostat connected to a cellphone to control and monitor analysis. The affecting parameters of DPAdSV were optimized. Under the optimal conditions for UA determination, the limit of detection of the developed sensor was 0.33 µmol L-1 and the limit of quantification 1.10 µmol L-1. Two linear ranges were produced: 1.0-30 µmol L-1 and 30-100 µmol L-1. The sensor was highly sensitive and demonstrated excellent reproducibility and selectivity, determining UA in blood serum with recoveries between 86.6 ± 0.6 and 94.7 ± 0.4%. The analysis results were in agreement with those of the hospital standard enzymatic method.


Asunto(s)
Técnicas Biosensibles , Quitosano , Grafito , Nanopartículas del Metal , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Electrodos , Oro , Rayos Láser , Porosidad , Reproducibilidad de los Resultados , Ácido Úrico/análisis
15.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-986256

RESUMEN

@#Xylazine is a sedative, analgesic and muscle relaxant widely applied in the veterinary field. However, owing to its depressant effect, xylazine has become a substance of abuse by humans. Misuse of xylazine not only triggers unwanted consequences (death), but also linked with various crimes. Google Scholar, PubMed and SciFinder were used to retrieve articles and case reports in relation to the misuses of xylazine and established analytical methods for forensic investigation until November 2021. Literatures reported the accidental and intended poisoning of xylazine, recreational use of xylazine and as an adulterant in recreational drugs. In addition to being a facilitator of crime and sexual assault, it is administered illegally to food producing animals as a sedative and to sports animals as a doping agent. Problems associated with the abuse of xylazine were highlighted in this review, covering the unknown prevalence of xylazine abuse and the need to revise the regulatory status of xylazine. In addition, limited screening and confirmatory methods that can be readily utilised to detect xylazine either alone or simultaneously with other substances of abuse, particularly useful for forensic toxicology and narcotic section were available in the literature. As a conventionally used veterinary drug, xylazine is undoubtedly a potentially hazardous drug, and the investigations on its potential abuse would enhance routine forensic examination to keep pace with the status of illicit drugs.

16.
J Chin Med Assoc ; 84(7): 722-727, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-34050107

RESUMEN

BACKGROUND: Low birth weight and preterm or early-term babies may have a higher risk of poor health. One of the main factors is the weight gain of a pregnant woman during gestational weeks in the second and third trimesters. Changes in weight over a month in a pregnant woman might also have an impact on infant outcomes. This study aimed to investigate the association between maternal weight at different time points and low birth weight and preterm or early-term babies (premature babies). METHODS: A total of 156 pregnant women were recruited. Maternal weight was collected at different gestational weeks. Maternal age, body mass index, delivery mode, delivery week, and infant weight were also recorded. Maternal data were restructured into a person-period format before mixed-effects multiple logistic regression was used. Various weight variables with either a fixed effect or time-varying effects were tested in the model. RESULTS: Thirty (19.23%) women had delivered low birth weight or premature babies. Multiple logistic regression model demonstrated that mothers with higher increases in weight at 32 weeks of gestation than that in the predelivery stage had a lower probability of having a low birth weight or premature baby (odds ratio [OR] = 0.64; 95% CI, 0.49-0.85; p < 0.001). Women with a weight increase of more than 2 kg in a 4-week gestation period had a higher probability of having a low birth weight or premature baby than those with an increment of <1 kg (OR = 8.43; 95% CI, 2.90-24.54; p < 0.001). CONCLUSION: An increase in weight gain after 32 weeks was shown to reduce the risk of low birth weight and premature babies. Maternal weight monitoring was suggested to be conducted every 4 weeks to minimize the chance of having a low birth weight and premature baby.


Asunto(s)
Ganancia de Peso Gestacional , Recién Nacido de Bajo Peso , Nacimiento Prematuro , Adulto , Índice de Masa Corporal , Femenino , Humanos , Malasia , Embarazo
17.
Anal Methods ; 13(13): 1601-1611, 2021 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-33730137

RESUMEN

Due to the outbreak of the COVID-19 pandemic, practicing personal hygiene such as frequent hand sanitising has become a norm. The making of effective hand sanitiser products should follow the recommended formulations, but the high demand worldwide for such affordable products could have made them a candidate for counterfeiting, thus deserving forensic determination and profiling for source determination or supply chain tracing. In this study, determination and discrimination of hand sanitisers was carried out by employing attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy combined with chemometrics. Fifty commercially available hand sanitisers were obtained from the market and analysed. ATR-FTIR profiles of each sanitiser were compared and decomposed by principal component analysis (PCA) followed by linear discriminant analysis (LDA). Physical observation enabled the discrimination of seven samples based on their respective colours, the presence of beads and their colours, and the physical forms of formulations. Subsequently, eight distinct patterns were observed through visual comparison of ATR-FTIR profiles of the remaining 43 samples. An initial unsupervised exploratory PCA model indicated the separation of two main groups with ATR-FTIR profiles similar to those of ethanol and isopropanol, respectively. The PCA score-LDA model provided good predictions, with a 100% correct classification into eight different groups. In conclusion, this study demonstrated a quick determination and discrimination of hand sanitiser samples, allowing screening for any restricted components and sample-to-sample comparison.


Asunto(s)
Desinfectantes para las Manos/normas , COVID-19 , Análisis de Fourier , Higiene de las Manos , Humanos , Espectroscopía Infrarroja por Transformada de Fourier
18.
J Pharm Biomed Anal ; 198: 113958, 2021 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-33662759

RESUMEN

A portable electrochemical sensor was developed to determine xylazine in spiked beverages by adsorptive stripping voltammetry (AdSV). The sensor was based on a graphene nanoplatelets-modified screen-printed carbon electrode (GNPs/SPCE). The electrochemical behavior of xylazine at the GNPs/SPCE was an adsorption-controlled irreversible oxidation reaction. The loading of graphene nanoplatelets (GNPs) on the modified SPCE, electrolyte pH, and AdSV accumulation potential and time were optimized. Under optimal conditions, the GNPs/SPCE provided high sensitivity, linear ranges of 0.4-6.0 mg L-1 (r = 0.997) and 6.0-80.0 mg L-1 (r = 0.998) with a detection limit of 0.1 mg L-1 and a quantitation limit of 0.4 mg L-1. Repeatability was good. The accuracy of the proposed sensor was investigated by spiking six beverage samples at 1.0, 5.0, and 10.0 mg L-1. The recoveries from this method ranged from 80.8 ± 0.2-108.1 ± 0.3 %, indicating the good accuracy of the developed sensor. This portable electrochemical sensor can be used to screen for xylazine in beverage samples as evidence in cases of sexual assault or robbery.


Asunto(s)
Técnicas Electroquímicas , Drogas Veterinarias , Bebidas , Electrodos , Xilazina
19.
Nanomaterials (Basel) ; 12(1)2021 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-35010025

RESUMEN

A 3D porous graphene structure was directly induced by CO2 laser from the surface of Kapton tape (carbon source) supported by polyethylene terephthalate (PET) laminating film. A highly flexible laser-induced porous graphene (LI-PGr) electrode was then fabricated via a facile one-step method without reagent and solvent in a procedure that required no stencil mask. The method makes pattern design easy, and production cost-effective and scalable. We investigated the performance of the LI-PGr electrode for the detection of methamphetamine (MA) on household surfaces and in biological fluids. The material properties and morphology of LI-PGr were analysed by scanning electron microscopy (SEM), energy dispersive x-ray (EDX) and Raman spectroscopy. The LI-PGr electrode was used as the detector in a portable electrochemical sensor, which exhibited a linear range from 1.00 to 30.0 µg mL-1 and a detection limit of 0.31 µg mL-1. Reproducibility was good (relative standard deviation of 2.50% at 10.0 µg mL-1; n = 10) and anti-interference was excellent. The sensor showed good precision and successfully determined MA on household surfaces and in saliva samples.

20.
J Forensic Sci ; 66(2): 608-618, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33202056

RESUMEN

Abuse of solvent-based adhesives jeopardizes world population, especially the young generation. Adhesive-related exhibits encountered in forensic cases might need to be determined if they could have come from a particular source or to establish link between cases or persons. This study was aimed to discriminate solvent-based adhesives, especially to aid forensic investigation of glue sniffing activities. In this study, thirteen brands with three samples each, totaling at 39 adhesive samples, were analyzed using attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy followed by chemometric methods. Experimental output showed that adhesive samples utilized in this study were less likely to change in their ATR-FTIR profiles over time, at least up to 2 months. No interference from plastic materials was noticed based on ATR-FTIR profile comparison. Physical examination could differentiate the samples into two groups, namely contact adhesives and cement adhesives. A principal component analysis-score linear discriminative analysis (PC-score LDA) model resulted in 100% and 98.6% correct classification in discriminating the two groups of adhesive samples, forming seven discriminative clusters. Test set with adhesive samples applied glass slide and plastic substrates also demonstrated a 100% correct classification into their respective groups. As a conclusion, the method allowed for discrimination of adhesive samples based on the spectral features, displaying relationship among samples. It is hoped that this comparative information is beneficial to trace the possible source of solvent-based adhesives, whenever they are recovered from a crime scene, for forensic investigation.

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