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1.
Biosensors (Basel) ; 14(3)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38534233

RESUMO

An increasing number of countries have started to decriminalize or legalize the consumption of cannabis for recreational and medical purposes. The active ingredients in cannabis, termed cannabinoids, affect multiple functions in the human body, including coordination, motor skills, memory, response time to external stimuli, and even judgment. Cannabinoids are a unique class of terpeno-phenolic compounds, with 120 molecules discovered so far. There are certain situations when people under the influence of cannabis may be a risk to themselves or the public safety. Over the past two decades, there has been a growing research interest in detecting cannabinoids from various biological matrices. There is a need to develop a rapid, accurate, and reliable method of detecting cannabinoids in oral fluid as it can reveal the recent intake in comparison with urine specimens, which only show a history of consumption. Significant improvements are continuously made in the analytical formats of various technologies, mainly concerning improving their sensitivity, miniaturization, and making them more user-friendly. Additionally, sample collection and pretreatment have been extensively studied, and specific devices for collecting oral fluid specimens have been perfected to allow rapid and effective sample collection. This review presents the recent findings regarding the use of oral fluid specimens as the preferred biological matrix for cannabinoid detection in a point-of-care biosensor diagnostic device. A critical review is presented, discussing the findings from a collection of review and research articles, as well as publicly available data from companies that manufacture oral fluid screening devices. Firstly, the various conventional methods used to detect cannabinoids in biological matrices are presented. Secondly, the detection of cannabinoids using point-of-care biosensors is discussed, emphasizing oral fluid specimens. This review presents the current pressing technological challenges and highlights the gaps where new technological solutions can be implemented.


Assuntos
Canabinoides , Cannabis , Fumar Maconha , Humanos , Sistemas Automatizados de Assistência Junto ao Leito , Saliva , Detecção do Abuso de Substâncias/métodos
2.
Molecules ; 28(20)2023 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-37894694

RESUMO

This work aimed to study the influence of the polybutylene succinate (PBS) content on the physical, thermal, mechanical, and chemical properties of the obtained polylactic acid (PLA)/PBS composite fibers. PLA/PBS blend fibers were prepared by a simple melt-blown process capable of yielding nanofibers. Morphological analysis revealed that the fiber size was irregular and discontinuous in length. Including PBS affected the fiber size distribution, and the fibers had a smoother surface with increased amounts of added PBS. Differential scanning calorimetry analysis (DSC) revealed that the crystallization temperature of the PLA sheet (105.8 °C) was decreased with increasing PBS addition levels down to 91.7 °C at 10 wt.% PBS. This suggests that the addition of PBS may affect PLA crystallization, which is consistent with the X-ray diffraction analysis that revealed that the crystallinity of PLA (19.2%) was increased with increasing PBS addition up to 28.1% at 10 wt% PBS. Moreover, adding PBS increased the tensile properties while the % elongation at break was significantly decreased.

3.
Polymers (Basel) ; 15(20)2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37896433

RESUMO

This research aimed to prepare nonwovens from polylactic acid and polybutylene succinate using the melt-blown process while varying the melt-blown process parameters, including air pressure (0.2 and 0.4 MPa) and die-to-collector distance (15, 30, and 45 cm). Increasing the air pressure and die-to-collector distance resulted in the production of smaller fibers. Simultaneously, the tensile strength was dependent on the polymer, air pressure, and die-to-collector distance used, and the percentage elongation at the break tended to increase with an increasing die-to-collector distance. Regarding thermal properties, the PBS nonwovens exhibited an increased level of crystallinity when the die-to-collector distance was raised, consistent with the degree of crystallinity obtained from X-ray diffraction analysis. Polylactic acid could be successfully processed into nonwovens under all six investigated conditions, whereas nonwoven polybutylene succinate could not be formed at a die-to-collector distance of 15 cm. However, both polymers demonstrated the feasibility of being processed into nonwovens using the melt-blown technique, showing potential for applications in the textile industry.

4.
Micromachines (Basel) ; 14(8)2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37630149

RESUMO

The ongoing advancement in the synthesis of new nanomaterials has accelerated the rapid development of non-enzymatic pesticide sensors based on electrochemical platforms. This study aims to develop and characterize Nano-ink for applying organophosphorus pesticides using paraoxon residue detection. Multi-walled carbon nanotubes, silicon carbide, and silver nanoparticles were used to create Nano-ink using a green synthesis process in 1:1:0, 1:1:0.5, and 1:1:1 ratios, respectively. These composites were combined with chitosan of varying molecular weights, which served as a stabilizing glue to keep the Nano-ink employed in a functioning electrode stable. By using X-ray powder diffraction, Raman spectroscopy, energy dispersive X-ray spectroscopy, and a field emission scanning electron microscope, researchers were able to examine the crystallinity, element composition, and surface morphology of Nano-ink. The performance of the proposed imprinted working electrode Nano-ink was investigated using cyclic voltammetry and differential pulse voltammetry techniques. The Cyclic voltammogram of Ag NPs/chitosan (medium, 50 mg) illustrated high current responses and favorable conditions of the Nano-ink modified electrode. Under the optimized conditions, the reduction currents of paraoxon using the DPV techniques demonstrated a linear reaction ranging between 0.001 and 1.0 µg/mL (R2 = 0.9959) with a limit of detection of 0.0038 µg/mL and a limit of quantitation of 0.011 µg/mL. It was concluded that the fabricated Nano-ink showed good electrochemical activity for non-enzymatic paraoxon sensing.

5.
J Clin Aesthet Dermatol ; 14(11): E64-E75, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34980962

RESUMO

BACKGROUND: Low-level light/laser therapy (LLLT) can potentially stimulate hair growth in pattern hair loss (PHL), with many available home-use LLLT devices of different designs and technology on the market. However, not all devices are cleared by the United States (US) Food and Drug Administration (FDA), with very few studies to support their efficacy. OBJECTIVES: This systematic review and meta-analysis aimed to investigate the effectiveness of FDA-approved LLLT devices for PHL treatment. METHODS: We included articles related to FDA-approved home-use LLLT devices on PubMed and Medline, using the FDA 510(K) Premarket Notification database and the systematic search of articles up to January 2020. The standardized mean difference (SMD) for the changes of hair density treated by LLLT versus sham devices was analyzed. RESULTS: Only 32 home-use LLLT devices have been approved by the FDA as of January 2020. The meta-analysis comprised seven double-blinded, randomized, controlled trials. The overall quantitative analysis yielded a significant increase in hair density in those treated by LLLT versus sham groups (SMD: 1.27, 95% confidence interval [CI]: 0.993-1.639). The subgroup analysis demonstrated the increased hair growth in male and female subjects with both comb- and helmet-type devices. There were significant LLLT sources in the LDs alone (SMD: 1.52, 95% CI: 1.16-1.88) and the LDs combination (SMD: 0.85, 95% CI: 0.55-1.16) (p=0.043). CONCLUSION: LLLT is potentially effective for PHL treatment. Nonetheless, the long-term follow-up study in patients with severe PHL with combined standard treatment and comparison between LLLT devices and energy sources is recommended.

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