Reagent Combination Research Articles

Friedel-Crafts Reactivity with Sulfondiimidoyl Fluorides for the Synthesis of Heteroaryl Sulfondiimines.

Sulfur functional groups are ubiquitous in molecules used in the pharmaceutical and agrochemical industries, and within these collections sulfones hold a prominent position. The double aza-analogues of sulfones, sulfondiimines, offer significant potential in discovery chemistry but to date their applications have been limited by the lack of convenient synthetic routes. The existing methods mainly rely on imination of low-valent-sulfur intermediates, or the combination of pre-formed organometallic reagents and electrophilic S(VI)-functionalities. Herein, we describe a Friedel-Crafts-type reaction of sulfondiimidoyl fluorides with (hetero)aryls. This new SuFEx reactivity benefits from broad functional group tolerance, mild reaction conditions, and does not require the use of pre-formed organometallic reagents. The efficient use of unprotected indoles and pyrroles, as well as furan, thiophene and carbocyclic aromatics, further demonstrates the advantages of these reactions. We show that the reactivity of the sulfondiimidoyl fluorides can be tuned by switching the N-substituents, allowing an expansion of the range of coupling partners. The utility of the transformation is exemplified by the synthesis of the sulfondiimine analogue of the HIV-I reverse transcriptase-inhibitor L-737,126.

B2(OH)4 and Et3N-BH3: A New Combination of Reagents for the Mild and Efficient Photoreduction of Nitro(hetero)arenes

AbstractAnilines are a common motif in many bioactive compounds and their production through the reduction of nitroarenes has become an essential method for their synthesis. We demonstrate that the combination of an amine-borane complex and hypoboric acid (tetrahydroxydiborane) under visible light irradiation can accomplish the reduction of nitroarenes to the corresponding anilines. Preliminary mechanistic studies suggest the generation of boryl radicals via a hydrogen atom transfer (HAT) step from the photoexcited nitroarene. Involvement of a parallel thermal pathway is demonstrated with the high reaction efficiency being partially attributed to both routes.

Retention Mechanisms of Basic Compounds in Liquid Chromatography with Sodium Dodecyl Sulfate and 1-Hexyl-3-Methylimidazolium Chloride as Mobile Phase Reagents in Two C18 Columns

Reversed-phase liquid chromatography (RPLC) relies on a non-polar stationary phase and a more polar hydro-organic mobile phase, where compound retention is primarily governed by hydrophobicity, with more hydrophobic compounds being retained longer. The introduction of secondary equilibria in the chromatographic system through additives, such as anionic surfactants and ionic liquids (ILs), was proposed to mitigate ionic interactions between positively charged analytes and the anionic free silanol groups in non-endcapped stationary phases, thereby preventing increased retention and peak tailing. Additionally, the combined hydrophobic and ionic interactions between cationic analytes and the ions in these additives was demonstrated to create mixed retention mechanisms that influence retention and selectivity. In this regard, this study investigates aqueous chromatographic systems incorporating both the anionic surfactant sodium dodecyl sulfate (SDS) and the IL 1-hexyl-3-methylimidazolium chloride as mobile phase reagents. This combination of reagents modulates the retention, eliminating the need for organic solvents and resulting in highly sustainable HPLC procedures. The chromatographic behavior was assessed using two different C18 columns (Zorbax Eclipse and XTerra-MS). The strength of solute interactions was estimated by calculating equilibrium parameters and the contributions of hydrophobic and ionic interactions through simple mathematical models. Focusing on the retention of six basic drugs (β-adrenoceptor antagonists), the study highlighted the significant role of ionic interactions. The results demonstrate the feasibility of using aqueous systems combining SDS and an IL for the efficient separation of moderately polar basic compounds without the use of organic solvents.

An Aza‐Prilezhaev‐Based Method for Inversion of Regioselectivity in Stereospecific Alkene 1,2‐Aminohydroxylations

AbstractUnder acidic conditions (TFA) and in the presence of water, BocNHOTs promotes stereospecific 1,2‐aminohydroxylations of alkenes. The processes involve intermolecular aza‐Prilezhaev aziridination followed by stereospecific SN2 opening by water. This reagent combination provides regiochemical outcomes that are opposite to, or more selective than those observed using epoxidation initiated 1,2‐aminohydroxylation protocols. Replacement of water by other nucleophiles allows 1,2‐amino(thio)etherification, diamination, aminoazidation and aminofluorination reactions. Intramolecular processes are also feasible, including unusual variants that evoke azabicyclobutane‐like reactivity.

An Aza-Prilezhaev-Based Method for Inversion of Regioselectivity in Stereospecific Alkene 1,2-Aminohydroxylations.

Under acidic conditions (TFA) and in the presence of water, BocNHOTs promotes stereospecific 1,2-aminohydroxylations of alkenes. The processes involve intermolecular aza-Prilezhaev aziridination followed by stereospecific SN2 opening by water. This reagent combination provides regiochemical outcomes that are opposite to, or more selective than those observed using epoxidation initiated 1,2-aminohydroxylation protocols. Replacement of water by other nucleophiles allows 1,2-amino(thio)etherification, diamination, aminoazidation and aminofluorination reactions. Intramolecular processes are also feasible, including unusual variants that evoke azabicyclobutane-like reactivity.

A-084 Performance evaluation of Sentinel Diagnostics’ Ammonia Ultra assay on Beckman Coulter AU/DxC AU Systems

Abstract Background The analytical performances of the Ammonia Ultra assay for in vitro quantitative enzymatic determination of Ammonia in human plasma have been evaluated on Beckman AU/DxC AU Systems. Ammonia, derived from the amino acids catabolism and from the action of intestinal bacteria on dietary proteins, is converted to non-toxic urea by the liver. An excess of ammonia can have toxic effects on the Central Nervous System with possible neurological disturbances. Elevated ammonia levels can also be observed in severe liver failure as may occur in Reye’s syndrome, viral hepatitis or cirrhosis. Methods Ammonia, in the presence of glutamate dehydrogenase (GLDH), combines with alpha-ketoglutarate and NADH to yield glutamate and NAD+. The decrease in 340 nm absorbance (NADH → NAD+) is proportional to the ammonia level in the examined plasma. The reagent contains excess of lactate dehydrogenase (LDH) to rapidly reduce endogenous pyruvate and avoid its interference with the assay system. Performances evaluation have been done following current CLSI guidelines protocols. Results 3 calibrator lots and 2 reagent lots have been used for testing. For each test and among different combinations of reagents and calibrators, worst case has been reported in the table. Conclusions Analytical performances of Ammonia Ultra assay on Beckman AU/DxC AU Systems meet the requirements for its use as quantitative determination of Ammonia in human plasma and make this assay very suitable for the routine measurement of this analyte.

Enhancing sludge thickening in continuous treatment using polymeric bubbles with cationic polymer P2900 and cocamidopropyl betaine.

Sludge thickening is a fundamental stage of treatment. This study investigated the application, in continuous treatment, of polymeric bubbles produced with cationic polymer P2900 and cocamidopropyl betaine (CAPB), a zwitterionic surfactant. The proposed reagent combination aims to form aerated flakes, solid waste structures, and rapidly rising air bubbles, ideal for treatments in compact units. Using this combination, it was possible to achieve a total solids concentration of 45% with the modified bubbles and 25% with the conventional water treatment. This level of thickening occurred under the following operating conditions: initial total solids (TS) concentration of 10g L-1, a flow rate of 5 L min-1, saturation pressure (psat) of 3atm, and polymer dosage of 10mg (gTS)-1. The suggested mechanism of action involves the adhesion of P2900 molecules to CAPB at the air/water interface, forming a lining on the bubble surface. Additionally, polymerized species form due to the residual aluminum (Al) in the sludge, which would occur during flocculation in the helical tubular flocculator (HTF), adsorbing the micelles and bubbles of CAPB. The critical micellar concentration (CMC) of CAPB was 0.26mmol L-1. Polymeric bubble technology can provide an efficient and cost-effective approach to sludge thickening in continuous treatment.

Synthesis of Phosphorodiamidate Morpholino Oligonucleotides (PMOs) Using Staudinger Reduction as a Deblocking Condition and Its Usefulness for Orthogonal Conjugation in Bi- and Trifunctionalized PMOs

AbstractThe synthesis of short phosphorodiamidate morpholino oligonucleotides (PMOs) has been successfully achieved using azidoaryl carbamate protected chlorophosphoramidate monomers. The deprotection step carried out in a neutral medium with triphenylphosphine-based reagents avoids the need for chlorinated solvents. This method uses a meticulously tailored combination of resin support, solvents, deblocking agents, and coupling reagents to ensure efficient synthesis. Additionally, the azidoaryl carbamate protecting group has been adapted as an orthogonal protection, enabling the development of bi- and trifunctionalized PMOs for bioconjugation. These advancements are expected to broaden the potential applications of PMOs in biomedical research.

Combined application of the endophyte Bacillus K1 and sodium dehydroacetate alleviates postharvest gray mold in grapes

Botrytis cinerea, which causes postharvest gray mold, is a primary pathogen that limits grape shelf-life and consumption and causes substantial yield loss worldwide. The combined use of biocontrol agents and food additives has attracted increasing interest. The effects of combined treatment with the endophyte Bacillus subtilis K1 and sodium dehydroacetate (SD) on the occurrence of gray mold and maintenance of grape fruit quality were studied. Treatment with a K1 suspension (1 × 108 CFU/ml) combined with 0.32 g/L SD resulted in markedly improved control of B. cinerea on grapes. The disease incidence and severity in the groups treated with K1 alone or in combination with SD were significantly lower than those in the control groups (P < 0.05) when the mixtures were applied 2 h after pathogen inoculation. Moreover, application of the mixture could maintain the appearance, firmness, total soluble solid (TSS) content and titratable acidity (TA) of grape fruit. Furthermore, the combination triggered increases in the activities of defense-related enzymes such as peroxidase (POD), phenylalanine ammonia lyase (PAL), catalase (CAT), superoxide dismutase (SOD) and polyphenol oxidase (PPO). Additionally, it could increase the vitamin C content. Thus, appropriate combinations of biocontrol agents and chemical reagents can provide effective protection against postharvest decay.

A Telescopic, Scalable and Industrially Feasible Method for the Synthesis of Antidepressant Drug, Moclobemide

AbstractAn improved, scalable, industrially feasible telescopic process for multigram synthesis of highly commercialized antidepressant drug, moclobemide has been developed. Unlike the conventional approaches, this process enjoys the privilege of being an economical, operationally simple, effectively scalable, and quantitative method for the synthesis of amide‐containing drug moclobemide, showcasing easy isolation and purification without the aid of column chromatography. An environmentally benign reagent combination of TBN and NHS very effectively converts the acyl source, 4‐chlorobenzaldehyde into its N‐hydroxysuccinimide ester intermediate, which simply affords the drug molecule after nucleophilic substitution with the amine source. The synthetic process has successfully been scaled‐up upto ~145 g scale with 75 % overall yield and &gt;95 % first crop HPLC purity.

Biopolymer-enhanced delivery of reactive sulfide reagents for in-situ mercury remediation of heterogeneous contaminated soils

Mercury pollution from natural and anthropogenic sources demands effective remediation. This study focuses on optimizing a chemical stabilization approach using sulfur-containing compounds to create stable mercury sulfide (HgS) and immobilize elemental mercury in polluted soils. We propose using xanthan gum biopolymer to enhance the in-situ delivery of sulfide microparticles, overcoming soil heterogeneities due to its non-Newtonian behavior. Stability tests indicated that increased biopolymer concentration enhances particle stability due to the viscous and shear-thinning behavior of the polymer solutions. Various combinations (12 solutions) of xanthan polymer, pyrite microparticles, and sulfide-containing reagents were tested in batch experiments. Pyrite microparticles slightly reduced the xanthan solution's viscosity while retaining its non-Newtonian character. All solutions effectively transformed liquid mercury droplets into cinnabar, demonstrating successful mercury stabilization. Notably, solutions containing PIAX and SIPX, xanthate organosulfur compounds, significantly reduced the dissolved concentration of elemental mercury. Column experiments demonstrated xanthan gum's superior performance for in-situ injection of pyrite microparticles and sulfide mixtures into the soil compared to conventional water injection. At a polymer concentration of 4 g/L, a stable displacement front and an 88 % recovery of the initially injected particle-suspension density were achieved. The combined effects of xanthate's floating behavior and xanthan gum's shear-thinning nature substantially enhanced the delivery of pyrite microparticles in porous media for soil mercury remediation. This combination reduced the aqueous elemental mercury concentration in artificially polluted sand by up to 97 %, particularly with the xanthate organosulfur compound, PIAX. Xanthate has a higher potential to react with elemental mercury to form cinnabar compared to sodium thiosulfate. Additionally, the pyrite microparticles, rendered hydrophobic in xanthate solutions, integrated into the mercury droplets, forming a black paste. This study introduces a promising approach for efficient elemental mercury stabilization in contaminated soils by integrating biopolymers, reactive soluble compounds, and pyrite microparticles for sustainable decontamination.

Comparative Analysis of Decellularization Methods for the Production of Decellularized Umbilical Cord Matrix.

The importance of decellularized extracellular matrix (dECM) as a natural biomaterial in tissue engineering and regenerative medicine is rapidly growing. The core objective of the decellularization process is to eliminate cellular components while maximizing the preservation of the ECM's primary structure and components. Establishing a rapid, effective, and minimally destructive decellularization technique is essential for obtaining high-quality dECM to construct regenerative organs. This study focused on human umbilical cord tissue, designing different reagent combinations for decellularization protocols while maintaining a consistent processing time. The impact of these protocols on the decellularization efficiency of human umbilical cord tissue was evaluated. The results suggested that the composite decellularization strategy utilizing trypsin/EDTA + Triton X-100 + sodium deoxycholate was the optimal approach in this study for preparing decellularized human umbilical cord dECM. After 5 h of decellularization treatment, most cellular components were eliminated, confirmed through dsDNA quantitative detection, hematoxylin and eosin (HE) staining, and DAPI staining. Meanwhile, Masson staining, periodic acid-silver methenamine (PASM) staining, periodic acid-Schiff (PAS) staining, and immunofluorescent tissue section staining results revealed that the decellularized scaffold retained extracellular matrix components, including collagen and glycosaminoglycans (GAGs). Compared to native umbilical cord tissue, electron microscopy results demonstrated that the microstructure of the extracellular matrix was well preserved after decellularization. Furthermore, Fourier-transform infrared spectroscopy (FTIR) findings indicated that the decellularization process successfully retained the main functional group structures of extracellular matrix (ECM) components. The quantitative analysis of collagen, elastin, and GAG content validated the advantages of this decellularization process in preserving and purifying ECM components. Additionally, it was confirmed that this decellularized matrix exhibited no cytotoxicity in vitro. This study achieved short-term decellularization preparation for umbilical cord tissue through a combined decellularization strategy.

Possibility and Prospects for Using Combined Coagulants-flocculants in the Urban Wastewater Treatment System

A method is proposed for producing a powdered combined reagent, including an aluminum-silicon coagulant-flocculant, a sorption material and an acidity regulator of treated wastewater, as well as using this reagent in the treatment system of multi-component urban wastewater treatment plants. It has been shown that the use of powdered reagents of various compositions ensures purification efficiency for suspended solids in the range from 66.1 to 94.1 %, and for COD – from 70.1 to 78.0 %.

Fenton-reactive groundwater circulation well for groundwater remediation of a toluene-contaminated site

ABSTRACT In order to improve the remediation efficiency of the groundwater circulation well (GCW) on toluene-contaminated soil, we used a combination of GCW and Fenton reagent for remediation. Taking a toluene-contaminated site in Suzhou City, Jiangsu Province, China, as an example, Fenton reagent with a molar ratio of H2O2/contaminant = 10:1 and H2O2/Fe2+ = 2:1 was added to GCW at an aeration rate of 0.005 m3/s. After 216 h of remediation, the toluene concentrations at the site were reduced to the remediation target values. In this study, the Fenton reagent was rapidly delivered to the influence radius of GCW, which reduced the time required for remediation and provided a new model for the application of GCW.

#2646 Precision verification and method comparison of anti-MPO anti-hsPR3 immunoassay on Alegria2 instrument

Abstract Background and Aims Antibodies to myeloperoxidase (anti-MPO) and proteinase 3 (anti-PR3) are recognized as the only clinically relevant antineutrophil cytoplasmic antibodies (ANCA) specificities so far. ANCA testing can be used in different clinical settings, especially in situations that require rapid diagnosis like renal-pulmonary syndrome that require result within 24 hours. The aim of this study was to perform analytical verification of the new automated single test ELISA based method on Alegria2 instrument to test if the reagents and analyser were acceptable for the routine use. Method For precision assessment we tested two concentration levels of commercial control material in triplicate for five days in a row. We used EASI acceptable criteria for precision for anti-MPO as well as for anti-hsPR3. For method comparison we included 50 patients with history or suspicion of vasculitis. Anti-MPO and anti-PR3 were measured using 5 different reagents: Anti-Myeloperoxidase ELISA (IgG) and anti-PR3-hn-hr ELISA (IgG) on Euroimmun Analyzer I-2P (EUROIMMUN AG, Lubeck, Germany), MPO and PR3 II chemiluminiscent immunoassay (CLIA) on IDS iSYS (IDS ISYS, Pouilly en Auxois, France), QUANTA Flash® MPO and QUANTA Flash® PR3 CLIA on BIO-FLASH® (Inova Diagnostics Inc, San Diego, USA), Anti-MPO and anti-PR3 hs on Alegria2 ELISA based method (Orgentec, Mainz, Germany), and Anti-MPO and anti-PR3 ELISA (Orgentec, Mainz, Germany). Results were categorized as positive or negative and we calculated kappa statistics as well as intraclass correlation coefficient. Complete statistical analysis was done using MedCalc statistical software (MedCalc version 14.8.1, Ostend, Belgium). Results Within-laboratory precision (CV%) for anti-MPO for normal and pathological controls were 5.73% and 15.14% respectively. For anti-PR3 hs within-laboratory precision (CV%) for normal and pathological controls were 5.46% and 18.89% respectively. Intraclass correlation coefficient showed excellent degree of consistency in average measures (0.9778 (95% CI: 0.9665-0.9862)) for anti-MPO and good reliability on single ratings (0.8981 (95% CI: 0.8522-0.9344). For anti PR3 intraclass correlation coefficient showed excellent degree of consistency in average measures (0.9257 (95% CI: 0.8873-0.9539)) but only moderate consistency in single ratings (0.7136 (95% CI: 0.6115-0.8053)). Separate Cohen`s kappa testing revealed almost perfect agreement for most reagent combination for anti- MPO (kappa from 0.825 to 0.958). For anti-PR3 we found moderate agreement between QUANTA Flash® PR3 and PR3 II IDS iSYS (kappa 0.520) but mostly substantial agreement (kappa from 0.629 to 0.865). We also found almost perfect agreement between anti-PR3 hs on Alegria2 and QUANTA Flash® PR3 (kappa = 0.901). Conclusion Our results showed a rather small relative variability and met the precision criteria defined by EASI initiative. Satisfactory agreement between methods is very reassuring but due to the lack of standardisation in autoimmune diagnostics imposes that information about methodological differences must be clearly stated on laboratory report. According to our results the new method for anti-MPO and anti-PR3 proved to be suitable for the routine use.

An experimental investigation on the foam proportion for coal dust suppression in underground coal mines

Coal dust presents a grave peril to the well-being of miners and mine safety. In the absence of preventive measures, the concentration of dust in the working area can exceed one thousand milligrams per cubic meter. Foam-based dust removal, owing to its noteworthy merits such as minimal water consumption and high efficiency in removing dust, has emerged as one of the prevailing technologies for dust elimination. To mitigate dust generation during excavation, extensive investigations have been undertaken to explore the impact of foam reagent solution ratios on the efficacy of foam dust removal. By meticulously selecting surfactants, the consequences of varying concentrations and combinations of foam reagents, wetting reagents and foam stabilizers on foaming performance are examined. Valuable insights into the functional relationship between initial foam volume, volume decay rate, and foam reagent concentration are obtained. Furthermore, an in-depth analysis is conducted to probe the influence of wetting reagent addition on coal dust wetting, foam formation, and stability, thereby elucidating the functional connection between wetting time and the concentration of the wetting reagent. Additionally, the ramifications of stabilizer addition on foam stability and other relevant foam properties undergo comprehensive exploration, ultimately leading to the discovery of the functional relationship between foam performance and stabilizer concentration. Notably, experimental findings demonstrate that the optimum ratio for the foam reagent solution is AOS: SDS: STPP: CDEA: water=5:1:4:1:9989. This specific composition exhibits superlative foam foaming performance, stability, and wetting characteristics. Following a meticulous evaluation of gas supply volume, the optimal foam proportion is determined to be a foam reagent solution of 8 m3/h accompanied by a gas supply rate of 100 m3/h. The dust suppression efficiency of the foam produced by the optimal foam proportion reaches an about 97%, substantiating its effectiveness in dust removal.

Combination of Tramiprosate, Curcumin, and SP600125 Reduces the Neuropathological Phenotype in Familial Alzheimer Disease PSEN1 I416T Cholinergic-like Neurons.

Familial Alzheimer's disease (FAD) is a complex and multifactorial neurodegenerative disorder for which no curative therapies are yet available. Indeed, no single medication or intervention has proven fully effective thus far. Therefore, the combination of multitarget agents has been appealing as a potential therapeutic approach against FAD. Here, we investigated the potential of combining tramiprosate (TM), curcumin (CU), and the JNK inhibitor SP600125 (SP) as a treatment for FAD. The study analyzed the individual and combined effects of these two natural agents and this pharmacological inhibitor on the accumulation of intracellular amyloid beta iAβ; hyperphosphorylated protein TAU at Ser202/Thr205; mitochondrial membrane potential (ΔΨm); generation of reactive oxygen species (ROS); oxidized protein DJ-1; proapoptosis proteins p-c-JUN at Ser63/Ser73, TP53, and cleaved caspase 3 (CC3); and deficiency in acetylcholine (ACh)-induced transient Ca2+ influx response in cholinergic-like neurons (ChLNs) bearing the mutation I416T in presenilin 1 (PSEN1 I416T). We found that single doses of TM (50 μM), CU (10 μM), or SP (1 μM) were efficient at reducing some, but not all, pathological markers in PSEN 1 I416T ChLNs, whereas a combination of TM, CU, and SP at a high (50, 10, 1 μM) concentration was efficient in diminishing the iAβ, p-TAU Ser202/Thr205, DJ-1Cys106-SO3, and CC3 markers by -50%, -75%, -86%, and -100%, respectively, in PSEN1 I417T ChLNs. Although combinations at middle (10, 2, 0.2) and low (5, 1, 0.1) concentrations significantly diminished p-TAU Ser202/Thr205, DJ-1Cys106-SO3, and CC3 by -69% and -38%, -100% and -62%, -100% and -62%, respectively, these combinations did not alter the iAβ compared to untreated mutant ChLNs. Moreover, a combination of reagents at H concentration was able to restore the dysfunctional ACh-induced Ca2+ influx response in PSEN 1 I416T. Our data suggest that the use of multitarget agents in combination with anti-amyloid (TM, CU), antioxidant (e.g., CU), and antiapoptotic (TM, CU, SP) actions might be beneficial for reducing iAβ-induced ChLN damage in FAD.

Evaluation of culture methods and chemical reagent combinations on CRISPR/Cas9 gene editing systems by lipofection in pig zygotes.

The delivery of CRISPR/Cas ribonucleoprotein (RNP) complexes is gaining attention owing to its high cleavage efficiency and reduced off-target effects. Although RNPs can be delivered into porcine zygotes via electroporation with relatively high efficiency, lipofection-mediated transfection appears to be versatile because of its ease of use, low cost, and adaptation to high-throughput systems. However, this system requires improvements in terms of embryo development and mutation rates. Therefore, this study elucidated the effects of culture methods and reagent combinations on the CRISPR/Cas9 gene editing systems by using three lipofection reagents: Lipofectamine™ CRISPRMAX™ Cas9 Transfection Reagent (CM), Lipofectamine™ 2000 Transfection Reagent (LP), and jetCRISPR™ RNP Transfection Reagent (Jet). Porcine zona pellucida-free zygotes were incubated for 5h with Cas9, a guide RNA targeting CD163, and the above lipofection reagents. When examining the effect of culture methods using 4-well (multiple embryo culture) and 25-well plates (single embryo culture) on the efficiency of CM-mediated zygote transfection, the culture of embryos in 25-well plates significantly increased the blastocyst formation rate; however, there was no difference in mutation rates between the 4-well and 25-well plates. When assessing the effects of individual or combined reagents on the efficiency of zygote transfection, the mutation rate was significantly lower for individual LP compared to individual CM- and Jet-mediated transfections. Moreover, combinations of lipofection transfection reagents did not significantly increase the mutation rate or mutation efficiency.

Tuning Optical Properties of Carbon Dots by Co‐doping Strategy for Versatile Applications

AbstractCarbon dots (CDs) with tunable photoluminescence was successfully prepared via selective co‐doping of three elements, including nitrogen, phosphorus and sulfur element by green one‐step hydrothermal method. Nitrogen‐sulfur‐doped CDs (red NS‐CDs), which emitted red fluorescence under UV excitation, were used to detect iron ions in the linear range 1–50 μM, yielding detectable limits as low as 94 nM. The nitrogen‐phosphorus‐doped CDs (blue NP‐CDs) exhibited blue fluorescence with quantum yields up to 34.5 %. When the concentration is 800 μg/mL, it showed excellent anticancer effect in vitro. The nitrogen‐sulfur‐phosphorus‐doped CDs (green NPS‐CDs) emitting green fluorescence showed a low cytotoxicity at a high concentration of 800 μg/mL and were used for intracelluar imaging of NCl−H292 cells. This study demonstrated the photoluminescent characteristics of carbon dots (CDs) and highlighted the ability to modify their peak fluorescence emission wavelengths through the flexible combination of specific reagents under comparable hydrothermal conditions. Additionally, it provided valuable insights into the efficient methodologies for synthesizing CDs suitable for various application scenarios.

Variability in combinations of APTT reagent and substrate plasma for a one-stage clotting assay to measure factor VIII products.

An investigation of the suitability of reagents for measuring FVIII products in a one-stage clotting assay (OSA) showed variations in their FVIII activity (FVIII:C). Most studies have focused on the activated partial thromboplastin time (APTT) reagent rather than FVIII-deficient plasma (F8DP), even though the APTT-based OSA is comprised of APTT reagents and factor-deficient plasma. A single-centre study was conducted to clarify variations in measurements of FVIII products in an OSA using a total of 12 reagent combinations, including four APTT reagents and three types of F8DP. FVIII:C in nine types of FVIII product-spiked plasma was measured using an OSA with four different APTT reagents and three types of F8DP. F8DP-dependent variations were found in addition to differences derived from APTT reagents. Variations in target recovery (TR) were observed for NovoEight®, Eloctate®, and Jivi®. Reduced TR for Jivi was found only for Pathromtin SL in combination with congenital F8DP (F8DP-3). This lower TR was not observed with alternative manufacturing lots of F8DP-3. The reduced TR for Jivi might be related to impaired contact activation due to lower factor XI activity in F8DP-3. In addition to APTT reagents, variations in F8DPs used for OSAs can also affect FVIII:C results. F8DPs as well as the APTT reagent used for OSA should be chosen with caution, and laboratories should evaluate reagents for F8DPs as they currently do for APTT reagents, especially when lot changes occur.