Detection of Cannabinoids in Oral Fluid Specimens as the Preferred Biological Matrix for a Point-of-Care Biosensor Diagnostic Device.

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.

Effect of Polybutylene Succinate Additive in Polylactic Acid Blend Fibers via a Melt-Blown Process.

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.

Effects of Melt-Blown Processing Conditions on Nonwoven Polylactic Acid and Polybutylene Succinate.

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.

Development and Characterization of Nano-Ink from Silicon Carbide/Multi-Walled Carbon Nanotubes/Synthesized Silver Nanoparticles for Non-Enzymatic Paraoxon Residuals Detection.

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.

Validation of an electrochemical sensor based on gold nanoparticles as a point-of-care test for quantitative determination of glycated hemoglobin.

Monitoring the level of glycated hemoglobin (HbA1c) has become the gold standard measure for diabetes mellitus (DM) diagnosis and control, used in conjunction with fasting blood glucose (FBG) and oral glucose tolerance test. This study aimed to investigate the applicability of a newly developed nanoparticle-based electrochemical sensor-multiwalled nanotubes incorporated with gold nanoparticles (POCT-HbA1cMWCNTs/AuNPs)-used as a routine point-of-care test (POCT) for detection of HbA1c for the diagnosis of DM. Finger-prick and venous blood samples were collected from 108 DM and 98 non-DM subjects to determine HbA1c and total hemoglobin by POCT-HbA1cMWCNTs/AuNPs compared with the standard HPLC method. The performance of the POCT-HbA1cMWCNTs/AuNPs was evaluated using the standard cut-off HbA1c level of >6.5%. The test's sensitivity, specificity, positive predictive value, and negative predictive value were 100.00%, 90.32%, 87.23%, and 100.00%, respectively. The probability of DM diagnosis in a subject with HbA1c >6.5% (positive predictive value) was 87.23% (82/94). The accuracy of the POCT-HbA1cMWCNTs/AuNPs was 94.18%, with a %DMV (deviation from the mean value) of 0.25%. The results indicate satisfactory assay performance and applicability of the POCT-HbA1cMWCNTs/AuNPs for diagnosis of DM using the cut-off criteria of HbA1c >6.5.

Biogenic synthesis of gold nanoparticles mediated by Spondias dulcis (Anacardiaceae) peel extract and its cytotoxic activity in human breast cancer cell.

Green synthesis is a new paradigm for the preparation of gold nanoparticles (AuNPs) due to its cost-effectiveness and favorable environmental impact. This study presented a simple phytosynthesis process for the preparation of AuNPs utilizing the aqueous peel extract of Spondias dulcis (SPE) (Anacardiaceae) as both a reducing and stabilizing agent. A visual color change from yellow to purple during the reaction implied the successful formation of SPE-AuNPs, which was confirmed by UV-vis spectroscopy. Transmission electron microscopy (TEM) images indicated that the SPE-AuNPs were predominantly spherical with a mean size of 36.75 ± 11.36 nm, and were comprised of crystalline Au, as indicated by X-ray diffraction. In terms of their potential application, SPE-AuNPs exhibit significant cytotoxic activity in a dose- and time-dependent manner to MCF-7 human breast cancer cells, while being non-toxic to Vero normal cells. The treatment of MCF-7 cells with SPE-AuNPs increased the production of intracellular reactive oxygen species (ROS). Herein, the findings highlight the potential contribution of phytosynthesized SPE-AuNPs to the development of novel nanomedicines for cancer treatment.