Search Results (7)

Background: In Siberian folk medicine, Sagan-Dalya (Rhododendron adamsii Rehder) of the Ericaceae family is used as a tonic and restorative in the form of infusions and decoctions. Pharmacological studies have shown that alcoholic extracts of this plant enhance performance and have anti-inflammatory and immunomodulatory effects. Rhododendron adamsii shoots accumulate essential oil (up to 1.6%), flavonoids (1.8–3.0%), tannins (up to 6.9%), phenolic carbolic acids, β-sitosterin, oleanolic and ursolic acids, simple phenolic compounds, and coumarins. Methods: Supercritical carbon dioxide extraction (SC-CO₂) is the most preferred environmentally friendly and selective method for extracting these natural compounds from the plant matrix of Rh. adamsii due to their high thermolability. Tandem mass spectrometry was applied to detect chemical compounds. Mass-spectrometry (MS) analysis was performed on an ion trap equipped with an ESI source in negative and positive ion modes. The capture rate was one spectrum/s for MS and two spectrum/s for MS/MS. All experiments were repeated three times. A four-stage ion separation mode (MS/MS mode) was implemented. Results: The operative parameters and working conditions have been optimized by different pressure (100–400 bars) and temperature (31–70 °C) regimes, and CO₂ flow rate (10–25 mL/min) with 1 C₂H₅OH as a co-solvent. The extraction time varied from 60 to 90 min. The maximum global yield of biologically active substances (BAS) from R. adamsii leaves and stems was observed under the following extraction conditions: Pressure: 350 bar, extraction temperature: 65 °C, extraction time: 1 h; the global yield of BAS was 8.5 mg/g of plant sample; the share of the co-solvent (C₂H₅OH) was 2%. In total, forty-nine different BAS were identified in the Rh. adamsii SC-CO₂ extracts. Conclusions: The obtained results may shed new light on the scientific basis for the traditional medicinal use of Rh. adamsii leaf and stem extracts. The pharmacological contribution of the identified phytocannabinoids requires further detailed study. It is hypothesized that the excellent transdermal permeability of supercritical extracts may open new therapeutic approaches using transdermal formulations based on SC-CO₂ extracts of Rh. adamsii. Full article

There is potential for cannabidiol to act as an analgesic, anxiolytic and antipsychotic active ingredient; however, there is a need to find alternate administration routes to overcome its low oral bioavailability. In this work, we propose a new delivery vehicle based on encapsulation of cannabidiol within organosilica particles as drug delivery vehicles, which are subsequently incorporated within polyvinyl alcohol films. We investigated the long-term stability of the encapsulated cannabidiol, as well as its release rate, in a range of simulated fluids with different characterization techniques, including Fourier Transform Infrared (FT-IR) and High-performance Liquid Chromatography (HPLC). Finally, we determined the transdermal penetration in an ex vivo skin model. Our results show that cannabidiol is stable for up to 14 weeks within polyvinyl alcohol films at a range of temperatures and humidity. Release profiles are first-order, consistent with a mechanism involving diffusion of the cannabidiol (CBD) out of the silica matrix. The silica particles do not penetrate beyond the stratum corneum in the skin. However, cannabidiol penetration is enhanced and is detected in the lower epidermis, which was 0.41% of the total CBD in a PVA formulation compared with 0.27% for pure CBD. This is partly due to an improvement of its solubility profile as it is released from the silica particles, but we cannot rule out effects of the polyvinyl alcohol. Our design opens a route for new membrane technologies for cannabidiol and other cannabinoid products, where administration via non-oral or pulmonary routes can lead to better outcomes for patient cohorts in a range of therapeutics. Full article

Breathalyzer is a common approach to measuring blood alcohol concentration (BAC) levels of individuals suspected of drunk driving. Nevertheless, this device is relatively high-cost, inconvenient for people with limited breathing capacity, and risky for COVID-19 exposure. Here, we designed and developed a smart wristband integrating a real-time noninvasive sweat alcohol metal oxide (MOX) gas sensor with a Drunk Mate, an Internet of Thing (IoT)-based alarming system. A MOX sensor acquired transdermal alcohol concentration (TAC) which was converted to BAC and sent via the IoT network to the Blynk application platform on a smartphone, triggering alarming messages on LINE Notify. A user would receive an immediate alarming message when his BAC level reached an illegal alcohol concentration limit (BAC 50 mg%; TAC 0.70 mg/mL). The sensor readings showed a high linear correlation with TAC (R² = 0.9815; limit of detection = 0.045 mg/mL) in the range of 0.10–1.05 mg/mL alcohol concentration in artificial sweat, achieving an accuracy of 94.66%. The sensor readings of ethanol in water were not statistically significantly different (p > 0.05) from the measurements in artificial sweat and other sweat-related solutions, suggesting that the device responded specifically to ethanol and was not affected by other electrolytes in the artificial sweat. Moreover, the device could continuously monitor TAC levels simulated in real-time in an artificial sweat testing system. With the integration of an IoT-based alarming system, the smart wristband developed from a commercial gas sensor presented here offers a promising low-cost MOX gas sensor monitoring technology for noninvasive and real-time sweat alcohol measurement and monitoring. Full article

Transdermal drug delivery systems (TDDS) have drawn more interest from pharmaceutical scientists because they could provide steady blood levels and prevent the first-pass metabolism over a longer period. Polyvinyl alcohol (PVA) has been widely used in this application due to its biocompatibility, non-toxicity, nanofiber and hydrogel-forming ability. Despite those benefits, their morphology would easily be destroyed by continuous water absorption and contribute to burst drug release due to its hydrophilicity. The aim of this study was to prepare the diclofenac sodium (DS)-medicated dual layer PVA patch using a combination of electrospinning and cryogelation (freeze–thaw) methods to improve the physicochemical properties and drug compatibility and investigate the release of the DS-medicated dual layer PVA patch. Morphological observations using scanning electron microscopy (SEM) verified the polymer−polymer interaction between both layers, whereas Fourier transform infrared (FTIR) spectroscopy has demonstrated the compatibility of DS in PVA matrix up to 2% w/v of PVA volume. The DS loads were found amorphously distributed efficaciously in PVA matrix as no visible spectra of DS–PVA interaction were detected. The DS-medicated dual layer PVA patch with a thicker nanofiber layer (3-milliliter running volume), three freeze–thaw cycles and 2% DS loading labeled as 2%DL_B3C show the lowest swelling capacity (18.47%). The in vitro assessment using Franz diffusion cells showed that the 2%DL_B3C indicates a better sustained release of DS, with 53.26% of the DS being released after 12 h. The 2%DL_B3C owned a flux (J_ss) of 0.256 mg/cm²/h and a permeability coefficient (K_p) value of 0.020 cm/h. Thus, the results demonstrate that DS-medicated dual layer PVA patches prepared via a combination of electrospinning and cryogelation are capable of releasing drugs for up to 24 h and can serve as a drug reservoir in the skin, thereby extending the pharmacologic effects of DS. Full article

In this paper, we report the fabrication and characterization of a portable transdermal alcohol sensing device via a human finger, using tin dioxide (SnO₂) chemoresistive gas sensors. Compared to conventional detectors, this non-invasive technique allowed us the continuous monitoring of alcohol with low cost and simple fabrication process. The sensing layers used in this work were fabricated by using the reactive radio frequency (RF) magnetron sputtering technique. Their structure and morphology were investigated by means of X-ray spectroscopy (XRD) and scanning electron microscopy (SEM), respectively. The results indicated that the annealing time has an important impact on the sensor sensitivity. Before performing the transdermal measurements, the sensors were exposed to a wide range of ethanol concentrations and the results displayed good responses with high sensitivity, stability, and a rapid detection time. Moreover, against high relative humidity (50% and 70%), the sensors remained resistant by showing a slight change in their gas sensing performances. A volunteer (an adult researcher from our volunteer group) drank 50 mL of tequila in order to realize the transdermal alcohol monitoring. Fifteen minutes later, the volunteer’s skin started to evacuate alcohol and the sensor resistance began to decline. Simultaneously, breath alcohol measurements were attained using a DRAGER 6820 certified breathalyzer. The results demonstrated a clear correlation between the alcohol concentration in the blood, breath, and via perspiration, which validated the embedded transdermal alcohol device reported in this work. Full article

Transdermal alcohol biosensors have the ability to detect the alcohol that emanates from the bloodstream and diffuses through the skin. However, previous biosensors have suffered from long-term fouling of the sensor element and drift in the resulting sensor readings over time. Here, we report a wearable alcohol sensor platform that solves the problem of sensor fouling by enabling drift-free signals in vivo for up to 24 h and an interchangeable cartridge connection that enables consecutive days of measurement. We demonstrate how alcohol oxidase enzyme and Prussian Blue can be combined to prevent baseline drift above 25 nA, enabling sensitive detection of transdermal alcohol. Laboratory characterization of the enzymatic alcohol sensor demonstrates that the sensor is mass-transfer-limited by a diffusion-limiting membrane of lower permeability than human skin and a linear sensor range between 0 mM and 50 mM. Further, we show continuous transdermal alcohol data recorded with a human subject for two consecutive days. The non-invasive sensor presented here is an objective alternative to the self-reports used commonly to quantify alcohol consumption in research studies. Full article

Human metabolism often results in the emission of many VOCs through the skin. Ethanol is one of volatile compounds which are evaporated by perspiration. The aim of our research consists to develop chemical sensors for monitoring ethanol emission after alcohol consumption. The interest of using chemical sensors is noninvasive measurement and controlling alcohol level in the human body and to make the link between these measurements and that in the blood or in the breath. Recent clinical trials demonstrated the feasibility and relevance of this measurement method. Metal oxide sensors were calibrated in respect of the thermodynamic conditions of the surface of the skin. In this paper we show the first sensor responses by perspiration. Full article