Naproxen membrane electrodes based on different plasticizers and quaternary ammonium salt tetraoctylammonium (S)-6-methoxy-α-methyl-2-naphthaleneacetate (NAP-TOA) were prepared. The electrode response to naproxen has the sensitivity of -59.2 mV decade(-1) over the linear range of 10(-4)-10(-1) mol L(-1) and limit of detection 1.80×10(-5) mol L(-1). This electrode has a response time 15-20s and can be used in the pH range 5.5-9.5. The selective coefficients were determined in relation to some organic and inorganic anions and excipients of pharmaceuticals. The notable property and attractive quality of the naproxen electrode are low cost, comfortable application and very long lifetime-about 20 months. The electrode was successfully applied for determination of naproxen in urine samples and pharmaceuticals by the calibration curve method and standard addition method. The obtained results are comparable and sometimes better than those obtained by pharmacopoeial method.
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http://dx.doi.org/10.1016/j.msec.2012.08.045 | DOI Listing |
Cell Rep
January 2025
Centre for Systems Neuroscience, University of Leicester, Leicester, UK; Hospital Del Mar Medical Research Institute (IMIM), Barcelona, Spain; Institució Catalana de Recerca I Estudis Avançats (ICREA), Barcelona, Spain; Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China. Electronic address:
In subjects implanted with intracranial electrodes, we use two different stories involving the same person (or place) to evaluate whether and to what extent context modulates human single-neuron responses. Nearly all neurons (97% during encoding and 100% during recall) initially responding to a person/place do not modulate their response with context. Likewise, nearly none (<1%) of the initially non-responsive neurons show conjunctive coding, responding to particular persons/places in a particular context during the tasks.
View Article and Find Full Text PDFJ Neurophysiol
January 2025
School of Kinesiology, Faculty of Health Sciences, The University of Western Ontario, London, ON, Canada.
The purpose was to assess whether visual feedback of torque contributes to motor unit (MU) firing rate reduction observed during post-activation potentiation (PAP) of skeletal muscle. From 15 participants 23 MUs were recorded with intramuscular fine-wire electrodes from the tibialis anterior during isometric dorsiflexion contractions at 20% of maximum, with and without both PAP and visual feedback of torque. A 5s maximal voluntary contraction (MVC) was used to induce PAP, and evoked twitch responses were assessed before and after.
View Article and Find Full Text PDFRSC Adv
January 2025
Nano-Science Center & Department of Chemistry, University of Copenhagen Universitetsparken 5 2100 København Ø Denmark
pH remains the most important chemical parameter and must be monitored for positive outcomes in areas as different as cheese making and fertilisation (IVF). Where blood gas analysers enable patient monitoring, starter cultures in cheese manufacturing are still monitored using conventional pH electrodes. Here, we present a homogeneous multiwell plate sensor for monitoring pH, with the same sensitivity as a pH electrode.
View Article and Find Full Text PDFAdv Mater
January 2025
Key Laboratory of Green Printing, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences (ICCAS), Beijing Engineering Research Center of Nanomaterials for Green Printing Technology, Beijing National Laboratory for Molecular Sciences (BNLMS), Beijing, 100080, P. R. China.
More than 70% of human information comes from vision. The eye is one of the most attractive sensing sites to collect biological parameters. However, it is urgent to develop a cost-effective and easy-to-use approach to monitor eyeball information in a minimally invasive way instead of current smart contact lenses or camera-based eyeglasses.
View Article and Find Full Text PDFAdv Mater
January 2025
Henry Royce Institute and Photon Science Institute, Department of Electrical and Electronic Engineering, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
As human-machine interface hardware advances, better sensors are required to detect signals from different stimuli. Among numerous technologies, humidity sensors are critical for applications across different sectors, including environmental monitoring, food production, agriculture, and healthcare. Current humidity sensors rely on materials that absorb moisture, which can take some time to equilibrate with the surrounding environment, thus slowing their temporal response and limiting their applications.
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