Functionalized graphene oxide tablets for sample preparation of drugs in biological fluids: Extraction of ritonavir, a HIV protease inhibitor, from human saliva and plasma using LC-MS/MS.

In this work, graphene oxide-based tablets (GO-Tabs) were prepared by applying a thin layer of functionalized GO on a polyethylene substrate. The GO was functionalized with amine groups (-NH2 ) by poly(ethylene glycol)bis(3-aminopropyl) terminated (GO-NH2 -PEG-NH2 ). The functionalized GO-Tabs were used for the extraction of ritonavir (RTV) in human saliva samples. RTV in plasma and saliva samples was analyzed using LC-MS/MS. Gradient LC system with MS/MS in the positive-ion mode [electrospray ionization (ESI+)] was used. The transitions m/z 721 → 269.0 and m/z 614 → 421 were used for RTV and the internal standard indinavir, respectively. This study determined the human immunodeficiency virus protease inhibitor RTV in human saliva samples using functionalized GO-Tab and LC-MS/MS, and the method was validated. The standard calibration curve for plasma and saliva samples was constructed from 5.0 to 2000 nmol L-1 . The limit of detection was 0.1 nmol L-1 , and the limit of quantification was 5.0 nmol L-1 in both plasma and saliva matrices. The intra- and inter-assay precision values were found to be between 1.5 and 5.8%, and the accuracy values ranged from 88.0 to 108% utilizing saliva and plasma samples. The extraction recovery was more than 80%, and the presented functionalized GO-Tabs could be reused for more than 10 extractions without deterioration in recovery

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

DESALINATION DEVICE AND METHOD OF MANUFACTURING SUCH A DEVICE

A device (10) for capacitive deionization of an aqueous media containing dissolved ion species, said device comprising a cell with a first primary electrode (2) and a second primary electrode (3) arranged opposite the first primary electrode (2) and preferably separated by at least one non-conductive spacer (4, 4'). A third electrode (7) is arranged between the first and the second electrode. The third electrode (7) is grounded whereas the first and the second electrodes are polarized versus the grounded third electrode.QC 20190311</p

Device for capacitive deionization of aqueous media and method of manufacturing such a device

The present disclosure relates to a device 10 for capacitive deionization of an aqueous media containing dissolved ion species. The device comprises a cell comprising a first primary electrode 2 and a second primary electrode 3 arranged opposite the first primary electrode 2 and preferably separated by at least one non-conductive spacer 4, 4'. A third electrode 7 is interposed between the first and the second electrode. The third electrode 7 is grounded whereas the first and the second electrodes are polarized versus the grounded third electrode. QC 20190311</p

DESALINATION DEVICE AND METHOD OF MANUFACTURING SUCH A DEVICE

A device (10) for capacitive deionization of an aqueous media containing dissolved ion species, said device comprising a cell with a first primary electrode (2) and a second primary electrode (3) arranged opposite the first primary electrode (2) and preferably separated by at least one non-conductive spacer (4, 4'). A third electrode (7) is arranged between the first and the second electrode. The third electrode (7) is grounded whereas the first and the second electrodes are polarized versus the grounded third electrode.QC 20190311</p

DESALINATION DEVICE AND METHOD OF MANUFACTURING SUCH A DEVICE

A device (10) for capacitive deionization of an aqueous media containing dissolved ion species, said device comprising a cell with a first primary electrode (2) and a second primary electrode (3) arranged opposite the first primary electrode (2) and preferably separated by at least one non-conductive spacer (4, 4'). A third electrode (7) is arranged between the first and the second electrode. The third electrode (7) is grounded whereas the first and the second electrodes are polarized versus the grounded third electrode.QC 20190311</p

Device for capacitive deionization of aqueous media and method of manufacturing such a device

The present disclosure relates to a device 10 for capacitive deionization of an aqueous media containing dissolved ion species. The device comprises a cell comprising a first primary electrode 2 and a second primary electrode 3 arranged opposite the first primary electrode 2 and preferably separated by at least one non-conductive spacer 4, 4'. A third electrode 7 is interposed between the first and the second electrode. The third electrode 7 is grounded whereas the first and the second electrodes are polarized versus the grounded third electrode. QC 20190311</p

Device for capacitive deionization of aqueous media and method of manufacturing such a device

The present disclosure relates to a device 10 for capacitive deionization of an aqueous media containing dissolved ion species. The device comprises a cell comprising a first primary electrode 2 and a second primary electrode 3 arranged opposite the first primary electrode 2 and preferably separated by at least one non-conductive spacer 4, 4'. A third electrode 7 is interposed between the first and the second electrode. The third electrode 7 is grounded whereas the first and the second electrodes are polarized versus the grounded third electrode. QC 20190311</p

Cephalhaematoma Mimicking an Extradural Haematoma due to MirrorImage Artifact on Sonography in a Term Neonate: A Case Report

Cephalhaematomas and subgaleal haematomas are among the most common birth injuries and are associated with birth trauma, forceps, and vacuum-assisted deliveries. They present as scalp swelling and are usually identified shortly after birth. During sonographic examination, if an ultrasound beam scatters off a mirror-like interface, it creates mirror-image artifacts that can cause a diagnostic dilemma. In this case report, a six-day-old neonate presented with a right-side parietal cephalhaematoma that appeared to resemble an epidural haematoma on routine sonographic examination. Gray scale ultrasound revealed an anechoic structure resembling an epidural haematoma in the right parietal region. However, a non-contrast-enhanced computed tomography (NECT) scan of the brain showed a cephalhaematoma without an underlying epidural haematoma. Further evaluation using colour Doppler sonography revealed normal vascular findings within an anechoic space, and gray scale imaging in the sagittal plane showed normal cerebral parenchyma without midline shift. These findings helped identify the observed structure as a mirror-image artifact. It is important to note that these artifacts can lead to diagnostic errors, resulting in additional investigations and causing anxiety for parents. Understanding and being aware of these artifacts can help avoid unnecessary imaging and reduce radiation exposure