Unraveling the potential of breath and sweat VOC capture devices for human disease detection: a systematic-like review of canine olfaction and GC-MS analysis

The development of disease screening methods using biomedical detection dogs relies on the collection and analysis of body odors, particularly volatile organic compounds (VOCs) present in body fluids. To capture and analyze odors produced by the human body, numerous protocols and materials are used in forensics or medical studies. This paper provides an overview of sampling devices used to collect VOCs from sweat and exhaled air, for medical diagnostic purposes using canine olfaction and/or Gas Chromatography-Mass spectrometry (GC-MS). Canine olfaction and GC-MS are regarded as complementary tools, holding immense promise for detecting cancers and infectious diseases. However, existing literature lacks guidelines for selecting materials suitable for both canine olfaction and GC-MS. Hence, this review aims to address this gap and pave the way for efficient body odor sampling materials. The first section of the paper describes the materials utilized in training sniffing dogs, while the second section delves into the details of sampling devices and extraction techniques employed for exhaled air and sweat analysis using GC-MS. Finally, the paper proposes the development of an ideal sampling device tailored for detection purposes in the field of odorology. By bridging the knowledge gap, this study seeks to advance disease detection methodologies, harnessing the unique abilities of both dogs and GC-MS analysis in biomedical research

Increased Range of Catalytic Activities of Immobilized Compared to Colloidal Gold Nanoparticles

Gold nanoparticles (AuNPs) can be described as nanozymes, species that are able to mimic the catalytic activities of several enzymes, such as oxidase/peroxidase, reductase, or catalase. Most studies in the literature focus on the colloidal suspension of AuNPs, and it is obvious that their immobilization could open the doors to new applications thanks to their increased stability in this state. This work aimed to investigate the behavior of surfaces covered by immobilized AuNPs (iAuNPs). Citrate-stabilized AuNPs (AuNPs-cit) were synthesized and immobilized on glass slides using a simple dip coating method. The resulting iAuNPs were characterized (surface plasmon resonance, microscopy, quantification of immobilized AuNPs), and their multi-enzymatic-like activities (oxidase-, peroxidase-, and catalase-like activity) were evaluated. The comparison of their activities versus AuNPs-cit highlighted their added value, especially the preservation of their activity in some reaction media, and their ease of reuse. The huge potential of iAuNPs for heterogeneous catalysis was then applied to the degradation of two model molecules of hospital pollutants: metronidazole and methylene blue

Separation Methods in Biomedical Analysis, a Booming Field

Many scientific endeavors are dependent upon the accurate quantification of drugs and endogenous substances, such as pharmacokinetics [...

Separation Methods in Biomedical Analysis, a Booming Field

Many scientific endeavors are dependent upon the accurate quantification of drugs and endogenous substances, such as pharmacokinetics [...

Physicochemical stability of nefopam and nefopam/droperidol solutions in polypropylene syringes for intensive care units

International audienceAbstractIntroduction : Nefopam has been reported to be effective in postoperative pain control with an opioid-sparing effect, but the use of nefopam can lead to nausea and vomiting. To prevent these side effects, droperidol can be mixed with nefopam. In intensive care units, high concentrations of nefopam and droperidol in syringes can be used with a continuous flow.Objectives : The first objective of this work was to study the physicochemical stability of a nefopam solution 2.5 mg/mL diluted in NaCl 0.9% in polypropylene syringes immediately after preparation and after 6, 24 and 48 hours at room temperature. The second objective was to study the physicochemical stability of mixtures of nefopam 2.5 mg/mL and droperidol 52 µg/mL diluted in NaCl 0.9% in polypropylene syringes at room temperature over 48 hours.Materials and methods : Three syringes for each condition were prepared. For each time of analysis, three samples for each syringe were prepared and analysed by high performance liquid chromatography coupled to photodiode array detection. The method was validated according to the International Conference on Harmonisation Q2(R1). Physical stability was evaluated by visual and subvisual inspection (turbidimetry by UV spectrophotometry). pH values were measured at each time of analysis.Results : Solutions of nefopam at 2.5 mg/mL and the mixture of nefopam 2.5 mg/mL with droperidol 52 µg/mL, diluted in NaCl 0.9%, without protection from light, retained more than 90% of the initial concentration after 48 hours storage at 20–25°C. No modification in visual or subvisual evaluation and pH values were observed.Conclusion : Nefopam solutions at 2.5 mg/mL and the mixture of nefopam 2.5 mg/mL with droperidol 52 µg/mL diluted in NaCl 0.9% were stable over a period of 48 hours at room temperature. These stability data provide additional knowledge to assist intensive care services in daily practice

Physicochemical degradation of phycocyanin and means to improve its stability: A short review

International audienceThe cyanobacterium Arthrospira platensis, spirulina, is a source of pigments such as phycobiliprotein, phycocyanin. Phycocyanin is used in the food, cosmetic, and pharmaceutical industries because of its antioxidant, anti-inflammatory, and anticancer properties. The different steps involved in extraction and purification of this protein can alter the final properties. In this review, the stability of phycocyanin (pH, temperature, and light) is discussed, considering the physicochemical parameters of kinetic modeling. The optimal working pH range for phycocyanin is between 5.5 and 6.0 and it remains stable up to 45 °C; however, exposure to relatively high temperatures or acidic pH decreases its half-life and increases the degradation kinetic constant. Phycobiliproteins are sensitive to light and preservatives such as mono- and di-saccharides, citric acid, or sodium chloride appear to be effective stabilizing agents. Encapsulation within nano- or micro-structured materials such as nanofibers, microparticles, or nanoparticles, can also preserve or enhance its stability

Selective complexation and extraction of Ag(I) and Zn(II) versus Pb(II) by polymer beads modified by attachment of a bipyridyl–calixarene-based chelate

International audienceThe selective extraction of silver(I) and zinc(II) species from ternary mixtures involving lead(II) as the main component was performed using a Wang benzaldehyde resin supported calixarene–bipyridyl ligand. The extraction efficiency and selectivity was evaluated and quantified by complexation experiments using ionic liquid chromatography. Silver and zinc were extracted while lead stayed in solution. The selective recovery of these ions was realized by a treatment of the loaded resin with EDTA for zinc, followed by nitric acid for silver

Physicochemical Stability of Vancomycin at High Concentrations in Polypropylene Syringes

ABSTRACTBackground: In severe infections, high-concentration vancomycin may be administered by continuous infusion. The dosage of vancomycin may reach 60 mg/kg per day. Objectives: To study the feasibility of preparing high-concentration vancomycin solutions (40 to 83.3 mg/mL), to study the effect of an electric syringe pump on the physical stability of high-concentration vancomycin, and to study the stability of vancomycin 62.5 and 83.3 mg/mL in 0.9% sodium chloride (0.9% NaCl) or 5% dextrose in water (D5W) with storage up to 48 h at room temperature. Methods: The following sets of syringes were prepared: (1) 4 syringes of vancomycin in 0.9% NaCl for each of 5 concentrations between 40 and 83.3 mg/mL (total 20 syringes); (2) 6 syringes at 83.3 mg/mL in 0.9%NaCl and 6 syringes at 83.3 mg/mL in D5W; and (3) 30 syringes at 83.3 mg/mL in D5W. Visual inspection was performed for all 3 syringe sets, and subvisual inspection for sets 1 and 2 (for periods of 24 h for set 1 and 48 h for sets 2 and 3). One syringe of vancomycin 83.3 mg/mL with each solvent was inserted into an electric syringe pump, and samples from the infusion line and collected after transit through the pump were inspected visually. Chemical stability was evaluated by high-performance liquid chromatography, and physical stability, pH, and osmolality were investigated. Results: For all sets of syringes, no physical modification was observed over time, nor were any changes observed after transit through the electric syringe pump. In 0.9% NaCl, vancomycin 62.5 and 83.3 mg/mL retained more than 90% of the initial concentration after 48 and 24 h, respectively; however, for the 83.3 mg/mL solution, precipitate was visible after 48 h. In D5W, vancomycin at 62.5 and 83.3 mg/mL retained more than 90%of the initial concentration after 48 h. Conclusion: It was feasible to prepare high-concentration solutions of vancomycin. The electric syringe pump did not cause any precipitation. Vancomycin in D5W at 62.5 and 83.3 mg/mL was stable over 48 h at room temperature. Precipitation occurred in 0.9% NaCl. D5W is therefore recommended as the solvent for this drug.RÉSUMÉContexte : En cas d’infection grave, de la vancomycine à forte concentration peut être administrée par perfusion continue à une dose pouvant atteindre 60 mg/kg par jour. Objectifs : Mener une étude de faisabilité portant sur la préparation de solutions de vancomycine à forte concentration (de 40 à 83,3 mg/mL); étudier l’effet d’un pousse-seringue électrique sur la stabilité physique de la vancomycine à forte concentration; et étudier la stabilité de la vancomycine (62,5 et 83,3 mg/mL) dans une solution de chlorure de sodium à 0,9 % (NaCl à 0,9 %) ou dans une solution aqueuse de dextrose à 5 % (D5W) après 48 h à la température ambiante.Méthodes : Trois ensembles de seringues ont été préparés : (1) quatre seringues de vancomycine dans une solution de NaCl à 0,9 %, à chacune des cinq concentrations comprises entre 40 et 83,3 mg/mL (20 seringues au total); (2) six seringues à 83,3 mg/mL dans une solution de NaCl à 0,9 % et six seringues à 83,3 mg/mL dans une solution de D5W; et (3) 30 seringues à 83,3 mg/mL dans une solution de D5W. Une inspection visuelle des trois ensembles de seringues et une inspection « sous-visuelle » des ensembles 1 et 2 ont eu lieu (période de 24 h pour l’ensemble 1 et de 48 h pour les ensembles 2 et 3). Une seringue contenant de la vancomycine à 83,3 mg/mL mélangée à chaque solvant a été insérée dans un pousse-seringue électrique, et les échantillons prélevés dans le tube de perfusion et ceux recueillis après leur passage dans la pompe ont été inspectés visuellement. La stabilité chimique a été évaluée par chromatographie liquide à haute performance et la stabilité physique, le pH ainsi que l’osmolalité ont eux aussi été étudiés. Résultats : Les trois ensembles de seringues n’ont présenté aucune modification physique avec le temps. Aucun changement n’a non plus été observé après le passage dans le pousse-seringue électrique. Dans la solution de NaCl à 0,9 %, la vancomycine à 62,5 et à 83,3 mg/mL a conservé plus de 90 % de sa concentration initiale respectivement après 48 et 24 h. Cependant, le précipité de la solution à 83,3 mg/mL était visible après 48 h. Dans la solution de D5W, la vancomycine à 62,5 et à 83,3 mg/mL a conservé plus de 90 % de sa concentration initiale après 48 h. Conclusion : La préparation de solutions de vancomycine à forte concentration est faisable. Le pousse-seringue électrique n’a pas causé de précipitation. La vancomycine dans la solution de D5W à 62,5 et à 83,3 mg/mL est restée stable pendant plus de 48 h à la température ambiante. Les précipitations se sont produites dans les solutions de NaCl à 0,9 %. On recommande donc la solution de D5W comme solvant pour ce médicament

Food-inspired innovations to improve the stability of active pharmaceutical ingredients

International audienceFood-processing and pharmaceutical industries share a lot of stability issues against the same physical, chemical, and microbiological phenomena. They also share some solutions to improve the stability as the use of preservatives and packaging. Ecological concerns lead to the development of tremendous innovations in food. Some of these innovations could also be beneficial in the pharmaceutical domain. The objective of this review is to evaluate the potential application of these findings in the pharmaceutical field and the main limits in terms of toxicity, environmental, economic and regulatory issues. The principal factors influencing the shelf-life were highlighted through the description of the stability studies usually performed in the pharmaceutical industry (according to European guidelines). To counter those factors, different solutions are currently available as preservatives and specific packaging. They were described and debated with an overview of recent food innovations in each field. The limits of the current solutions in the pharmaceutical field and the innovation in the food field have inspired a critical pharmaceutical outlook. The active and intelligent packaging for active pharmaceutical ingredients of the future is imagined

Cu(I) and Zn(II) chelations on polymer beads modified by attachment of a bipyridyl-calixarene-based chelate

International audienceA new chelating calix[4]arene derivative incorporating two bipyridyl groups and one primary amino attachment function at the lower rim has been synthesised and coupled to Wang benzaldehyde resin. The new material effectively displayed complexation abilities towards Cu(I) and Zn(II) transition metal cations. The grafting efficiency was evaluated and quantified by complexation experiments, using UV/visible spectrophotometry, and ionic chromatography