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A new "cardo" bisphenol viz., 1-(2-(1,1-bis(4-hydroxyphenyl)-3-oxoisoindolin-2-yl)ethyl)-3,4-dimethyl-1H-pyrrole-2,5-dione (PPH-MA) was synthesized in a two-step reaction sequence starting from phenolphthalein. PPH-MA was utilized as a step-growth monomer for the synthesis of a homo- and fourco-polycarbonates bearing pendant 2,3-dimethylmaleimido groups (PC-MAs) via solution polycondensation of PPH-MA or various mol % compositions of PPH-MA and bisphenol-A, respectively, with triphosgene.1H NMR spectroscopy confirmed the chemical structure and composition of PC-MAs. Inherent viscosity and number average molecular weight values of PC-MAs were in the range 0.45–0.64 dL g−1 and 18,300 − 36,200 g mol−1, respectively, indicating the formation of polymers of medium to reasonably high molecular weights. Tough, transparent and flexible films of PC-MAs could be cast from chloroform solution. X-ray diffraction studies indicated the amorphous nature of PC-MAs. The 10% weight loss temperature (T10) values of PC-MAs were in the range 373–443 °C indicating their good thermal stability. [ABSTRACT FROM AUTHOR]

Thin-film composite (TFC) membranes have gradually replaced some traditional technologies in the extraction, separation, and concentration of high value-added pharmaceutical ingredients due to their controllable microstructure. Nevertheless, devising solvent-stable, scalable TFC membranes with high permeance and efficient molecule selectivity is urgently needed to improve the separation efficiency in the separation process. Here, we propose phenolphthalein, a commercial acid-base indicator, as an economical monomer for optimizing the micropore structure of selective layers with thickness down to 30 nanometers formed by in situ interfacial reactions. Molecular dynamics simulations indicate that the polyarylate membranes prepared using three-dimensional phenolphthalein monomers exhibit tunable microporosity and higher pore interconnectivity. Moreover, the TFC membranes show a high methanol permeance (9.9 ± 0.1 liters per square meter per hour per bar) and small molecular weight cutoff (-289 daltons) for organic micropollutants in organic solvent systems. The polyarylate membranes exhibit higher mechanical strength (2.4 versus 0.8 gigapascals) compared to the traditional polyamide membrane. [ABSTRACT FROM AUTHOR]

Aiming at the problem of phase separation between thermoplastic toughener and epoxy after curing, which leads to the reduction of mechanical properties, in this paper we improve the compatibility of the two phases by introducing reactive groups into the molecular chain of thermoplastic resins, thus improving the impact strength of the epoxy system. Phenolphthalein polyether sulfone (C‐PESC) with designable and controllable carboxyl group content was prepared via SN2 nucleophilic substitution copolymerization. Further C‐PESC was evaluated for epoxy toughening, and the effects of carboxyl group content of C‐PESC on mechanical properties and thermal stability of the resin system were investigated. The results show that C‐PESC resin has good compatibility with E51 epoxy resin. Carboxyl group accelerates the dissolution rate of thermoplastic resins in epoxy and also participates in the curing reaction with epoxy to enhance the interfacial bonding ability between the toughening component and the matrix resin. The reactive toughener C‐PESC can not only improve the impact properties of E51 epoxy, but also maintain the high Tg and thermal properties of the resin system. Among them, the addition of 5 PHR of C‐PESC3 increased the impact strength of the modified resin by 45%, with uniform fracture surface and tough fracture shape. [ABSTRACT FROM AUTHOR]

In this study, the primary objective is to synthesize a novel fluorescent Rh‐PP‐Rh compound and explore its extensive range of photochemical behaviors. Initially, the synthesis of the novel Rh‐PP‐Rh was carried out for this purpose. Subsequently, UV‐Vis and fluorescence spectroscopy were employed to investigate the interactions between Rh‐PP‐Rh and a diverse array of ions in aqueous solvent systems. Through fluorescence and UV‐Vis studies, it was observed that Rh‐PP‐Rh demonstrated turn‐on sensor properties in the presence of Hg2+ ions. Furthermore, the limits of detection (LOD) and association constant (Ka) values for Rh‐PP‐Rh/Hg2+ were determined as 334 nM and 9.13×1011 M−2, respectively. Additionally, the reversible studies demonstrated a switchable on/off response upon alternate addition of HgCl2 and [Bu4N]F to Rh‐PP‐Rh. These findings suggest that the probe Rh‐PP‐Rh also possesses specific sensor properties for F− ions in the presence of mercury. In addition, the investigation encompassed an assessment of the visual analysis of the color alterations of Rh‐PP‐Rh both on filter paper and in an EtOH/H2O solution. The findings demonstrated that Rh‐PP‐Rh can be successfully utilized in solutions containing mercury, as it generates significant color transformations. [ABSTRACT FROM AUTHOR]

Eco-friendly acid base indicators (anthocyanins) are always a center of attention in quantitative volumetric analysis as substitute for synthetic dye indicators. The purpose of the study is to promote utilization of Punica granatum (pomegranate) peel biomass by developing a novel eco-friendly acid–base indicator for titrimetric analysis. Pomegranate peel extract (PPEx) was prepared by ultrasonic probe sonication, a green method for extraction. The obtained extracts were evaluated for total phenol, anthocyanin content and the color change ability analysis (CIEL*a*b* analysis). The pKa of PPEx was determined, the effectiveness of PPEx as indicator was established in different acid–base titrations and compared with conventional synthetic indicators phenolphthalein and methyl orange. The aspirin powder and tablet (Ecosprin) were analyzed by using PPEx as indicator. An attempt was also made to develop PPEx pH indicator paper. The aqueous and ethanolic PPEx prepared by ultrasonic probe sonication contains 657.1 ± 21 and 718.1 ± 21 mg/LGAE of total phenols and 38.49 ± 0.83 and 42.91 ± 2.10 mgC3G/100gm of anthocyanins, respectively.The PPEx and pH indicator paper shows color change with the pH of solution. The pKa of PPEx was 7.14. PPEx was served as eco-friendly substitute for phenolphthalein and methyl orange indicators. PPEx was effective to analyze aspirin. The statistical analysis ensures the reliability and effectiveness of PPEx as an eco-friendly indicator in acid base titrations as substitute for the synthetic dye indicator. [ABSTRACT FROM AUTHOR]

Copyright of Karaelmas Science & Engineering Journal / Karaelmas Fen ve Mühendislik Dergisi is the property of Karaelmas Science & Engineering Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aluminum butylmethylphosphinate AiBMP as a flame retardant and phenolphthalein as a synergistic agent were applied in a thermoplastic polyester elastomer (TPEE)) in the current study. The thermal properties, flame retardancy, crystallization and mechanical properties of TPEE/AiMBP with or without phenolphthalein were investigated using various characterizations, including the limiting oxygen index (LOI), vertical burning test (UL 94), thermogravimetric analysis TG, differential scanning calorimetry, microcombustion calorimeter (MCC), scanning electron microscopy (SEM), and mechanical tests. The results revealed that AiBMP alone is an efficient flame retardant of TPEE. Adding 15 wt.% AiBMP increases the LOI value of TPEE from 20% to 36%. The formula TPEE-15 AiBMP passed the UL 94 V-0 rating with no dripping occurring. The MCC test shows that AiBMP depresses the heat release of TPEE. In comparison with pure TPEE, the heat release rate at peak temperature and the heat release capacity of TPEE-15AiBMP are reduced by 46.1% and 55.5%, respectively. With the phenolphthalein added, the formula TPEE/13AiBMP/2Ph shows a higher char yield at high temperatures (>600 °C), and the char layer is stronger and more condensed than TPEE-15AiBMP.The tensile strength and elongation at break values of TPEE-13AiBMP-2Ph are increased by 29.63% and 4.8% in comparison with TPEE-15AiBMP. The SEM morphology of the fracture surface of the sample shows that phenolphthalein acts as a plasticizer to improve the dispersion of AiBMP within the matrix. The good char charming ability of phenolphthalein itself and improved dispersion of AiBMP make the TPEE composites achieve both satisfying flame retardancy and high mechanical properties. [ABSTRACT FROM AUTHOR]

This study presents a computational chemistry experiment designed for junior undergraduates majoring in chemistry in the structural chemistry course, focusing on the discoloration principle of phenolphthalein indicator. The experiment serves as a fundamental investigation into discoloration reactions in the inorganic chemistry course. By employing the Gaussian program, the discoloration processes of phenolphthalein are explored. Through the analysis of macroscopic phenomena, such as changes in UV-Vis absorption spectra before and after discoloration, students gain insights into the mechanism of phenolphthalein discoloration from various microscopic perspectives. Additionally, the "class-micro-topic-flipped classroom" approach is employed to foster scientific innovation by incorporating knowledge extension training. [ABSTRACT FROM AUTHOR]

The US Environmental Protection Agency (USEPA) is faced with long lists of chemicals that require hazard assessment. The present study is part of a larger effort to develop in vitro assays and quantitative structure–activity relationships applicable to untested chemicals on USEPA inventories through study of estrogen receptor (ER) binding and estrogen‐mediated gene expression in fish. The present effort investigates metabolic activation of chemicals resulting in increased estrogenicity. Phenolphthalin (PLIN) was shown not to bind rainbow trout (Oncorhynchus mykiss) ER (rtER) in a competitive binding assay, but vitellogenin (Vtg) expression was induced in trout liver slices exposed to 10–4 and 10–3.7 M PLIN. Phenolphthalein (PLEIN), a metabolite of PLIN, was subsequently determined to be formed when slices were exposed to PLIN. It binds rtER with a relative binding affinity to 17β‐estradiol of 0.020%. Slices exposed to PLEIN expressed Vtg messenger RNA (mRNA) at 10–4.3, 10–4, and 10–3.7 M, with no detectable PLIN present. Thus, Vtg expression noted in PLIN slice exposures was explained by metabolism to PLEIN in trout liver slices. A second model chemical, 4,4′‐methylenedianiline (MDA), was not shown to bind rtER but did induce Vtg mRNA production in tissue slices at 10–4.3, 10–4, and 10–3.7 M in amounts nearly equal to reference estradiol induction, thus indicating metabolic activation of MDA. A series of experiments were performed to identify a potential metabolite responsible for the observed increase in activity. Potential metabolites hydroxylamine‐MDA, nitroso‐MDA, azo‐MDA, and azoxy‐MDA were not observed. However, acetylated MDA was observed and tested in both ER‐binding and tissue slice Vtg induction assays. Environ Toxicol Chem 2023;42:2747–2757. © 2023 SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

Kurzfassung: Die Carbonatisierung von Beton und der damit einhergehende Verlust der Passivierung der Stahlbewehrung stellt jeher eine Herausforderung hinsichtlich der Dauerhaftigkeit von Stahlbetonbauwerken dar. Um eine Schädigung infolge der Korrosion der Bewehrung zu vermeiden und Instandsetzungsmaßnahmen zum Erhalt der Passivierung rechtzeitig durchzuführen, gilt es die Carbonatisierungstiefe des Betons zu bestimmen. Die Bestimmung der Carbonatisierungstiefe mithilfe des pH‐Indikators Phenolphthalein stellt diesbezüglich den Stand der Technik dar, wird hierbei jedoch nur indirekt die Carbonatisierung des Betons auf Grundlage des pH‐Werts bestimmt. Eine direkte Messung der mit der Carbonatisierung einhergehenden strukturellen Änderungen, welche ebenfalls eine Änderung der Transporteigenschaften des Betons hervorruft, wird mithilfe des Phenolphthaleintests nicht erfasst. Mithilfe der einseitigen Wasserstoffkernspinresonanz (1H NMR) ist eine tiefenabhängige Untersuchung der Gefügestruktur möglich. Erste Ergebnisse zeigen, dass eine Ableitung des Carbonatisierungsfortschritts anhand der NMR‐Untersuchungen an Mörtel möglich ist. Mithilfe der Korrelation weiterer Untersuchungsmethoden kann ein umfassendes Verständnis des Carbonatisierungsprozesses gewonnen werden. [ABSTRACT FROM AUTHOR]

In this paper, a cellulose-based hydrogel with the ability to lower glucose levels, scavenge reactive oxygen species (ROS), and colorimetrically monitor early lesions was synthesized to address the issue of glucose and H2O2 overexpression on the wound surface. Briefly, boronic acid pinacol ester containing phenolphthalein (BAPE-PPH) was employed as a crosslinker to react with hydroxypropyl methylcellulose (HPMC) to afford hydrogels (HPMC@PPH-Hs) with good biocompatibility. Because glucose has higher affinity for the phenylboronic ester group than cellulose derivatives, the HPMC@PPH-Hs showed excellent glucose-lowering performance. The presence of B-C bonds in the network endows the as-obtained hydrogel with H2O2 sensitivity, and cleavage of the B-C bonds forces the transformation of BAPE-PPH moieties into PPH, giving rise to colorimetric behaviour. Thus, the obtained HPMC@PPH-Hs provide information to enrich the family of smart hydrogels, and its potential application in diabetic wound healing may be desirable. [ABSTRACT FROM AUTHOR]

Different building blocks in organic molecules could induce complex intermolecular interactions to lead to different supramolecular micro/nanostructures in bulk and solution states. Herein, the first new phenolphthalein-based hexacatenar containing a central phenolphthalein fluorochrome functionalized with two dendritic wings is synthesized by click reaction. The polarized optical microscopy, differential scanning calorimetry, and small-angle X-ray diffraction data demonstrated that the reported phenolphthalein-based hexacatenar could self-assemble into hexagonal columnar mesophase in the bulk state and could form organogel with distinct morphologies in some common organic solvents due to intermolecular interactions. Density functional theory calculation results showed highly twisted molecular conformation, distinct charge distribution, and asymmetrical electronic property, which might be essential for the stabilization of columnar mesophase and organogel. Therefore, this work provides a method to develop soft materials containing different functional building blocks with complex self-assemblies. [ABSTRACT FROM AUTHOR]

The nucleophilic substitution reaction of bisphenol A, Phenolphthalein, and resorcinol with 2-(4-fluorobenzoyl)benzoic acid gave previously undescribed diketoacids and their pseudochlorides. New polyarylenediphthalides with two hinged ether groups in the main chain, two of which (based on bisphenol A and resorcinol) exhibit a highly elastic state, were synthesized by the self-condensation of the pseudochlorides. [ABSTRACT FROM AUTHOR]

Copyright of Journal of the Japan Research Association for Textile End-Uses / Sen'i Seihin Shohi Kagaku is the property of Japan Research Association for Textile End-Uses / Sen'i Seihin Shohi Kagaku and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Our goal was to quantify the pH and total acidity of human milk fortified with human milk fortifiers (HMFs), powder infant formulas, and protein additives. Methods: Commercial liquid HMFs and powder infant formulas were added to pasteurized pooled donor human milk in triplicate and stirred. The pH of unfortified and fortified human milk at 22, 24, 26, 27, 28, and 30 kcal/ounce (624, 680, 737, 765, 794, and 850 kcal/g, respectively) was determined using a pH meter. Phenolphthalein acidity at 24 and 30 kcal/ounce (680 and 850 kcal/g, respectively) was determined using diluted sodium hydroxide. Results: The pH of unfortified human milk increased within the first hour (6.52 ± 0.06 vs 6.62 ± 0.05, P < 0.0001). Changes in pH largely correlated with caloric density; however, directional changes varied considerably between HMFs and powder infant formulas. Two liquid HMFs demonstrated modest reductions in pH with increasing caloric density whereas one liquid HMF alkalinized human milk with increasing caloric density (analysis of variance P < 0.0001). Phenolphthalein acidity was significantly higher for five HMFs and lower for one HMF at 30 kcal/ounce (850 kcal/g) but not 24 kcal/ounce (680 kcal/g). Powder infant formulas generally increased pH with increasing caloric density (analysis of variance P < 0.0001), but no differences in phenolphthalein acidity were noted. Conclusion: Changes in acid/base balancefor fortified human milk are variable and may be a consideration when selecting a fortifying agent for human milk. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Owing to the giant significance of organic dyes in both analytical as well as supramolecular chemistry, here, we report an efficient and green methodology for the preparation of indicator dyes, namely fluorescein and phenolphthalein. This particular method involves an inexpensive, reusable, and biodegradable deep eutectic solvent (DES) of choline chloride (ChCl) and zinc chloride (ZnCl2) in a ratio of 1 : 2, to furnish the corresponding dyes with an appropriate stoichiometry of the easily accessible starting materials. Strikingly, in this procedure, DES played a two‐fold role both as a catalyst as well as solvent and was efficiently recycled for four successive runs with no substantial cascading in the yields of the anticipated products. This simple yet efficient environmentally realistic protocol, to our best knowledge, is the first method, whereby DES has been employed in the successful preparation of any dye molecule to date. Hopefully, this novel procedure for dye(s) synthesis will be of much importance not only from the researchers perspective, but it will also provide a new way for both undergraduate and postgraduate level experiments. [ABSTRACT FROM AUTHOR]

Poly(arylene ether)s with different molecular weights were synthesized via a two‐step nucleophilic substitution polymerization by adjusting reaction parameters based on phenolphthalein (PHT) and decafluorobiphenyl (DFBP). The chemical structures and properties were identified by Fourier transform infrared, NMR, gel permeation chromatography, differential scanning calorimetry, thermogravimetric analysis, dynamic thermomechanical analysis (DMA), and so forth. The number‐average molecular weight (Mn) of the resulting polymers was in the range of 23.0–49.3KDa. FPAEs (polyarylether including perfluorobiphenyl structure) were demonstrated to have outstanding thermo‐resistance with 5% weight loss temperature of about 482–520°C (N2) and high‐glass transition temperature (about 240–250°C). FPAEs can be dissolved in conventional organic solvents, possessing excellent film‐forming properties. The good mechanical properties of FPAEs were confirmed by the DMA data, with Young's modulus greater than 1.0 Gpa and modulus retention rate at 230°C >67%. FPAEs also showed good hydrophobicity and low‐water absorption, in particular, FPAE‐1 (FPAE‐1‐5 were the polycondensation products of PHT and DFBP, just the polymerization conditions were slightly modified) exhibited favorable dielectric properties: at 1 MHz, the dielectric constant and dielectric loss was 2.58 and 0.0053, respectively. Thus, FPAE‐1 has broad prospective applications in microelectronic devices and communication technology. [ABSTRACT FROM AUTHOR]

Aluminum butylmethylphosphinate AiBMP as a flame retardant and phenolphthalein as a synergistic agent were applied in a thermoplastic polyester elastomer (TPEE)) in the current study. The thermal properties, flame retardancy, crystallization and mechanical properties of TPEE/AiMBP with or without phenolphthalein were investigated using various characterizations, including the limiting oxygen index (LOI), vertical burning test (UL 94), thermogravimetric analysis TG, differential scanning calorimetry, microcombustion calorimeter (MCC), scanning electron microscopy (SEM), and mechanical tests. The results revealed that AiBMP alone is an efficient flame retardant of TPEE. Adding 15 wt.% AiBMP increases the LOI value of TPEE from 20% to 36%. The formula TPEE-15 AiBMP passed the UL 94 V-0 rating with no dripping occurring. The MCC test shows that AiBMP depresses the heat release of TPEE. In comparison with pure TPEE, the heat release rate at peak temperature and the heat release capacity of TPEE-15AiBMP are reduced by 46.1% and 55.5%, respectively. With the phenolphthalein added, the formula TPEE/13AiBMP/2Ph shows a higher char yield at high temperatures (>600 °C), and the char layer is stronger and more condensed than TPEE-15AiBMP.The tensile strength and elongation at break values of TPEE-13AiBMP-2Ph are increased by 29.63% and 4.8% in comparison with TPEE-15AiBMP. The SEM morphology of the fracture surface of the sample shows that phenolphthalein acts as a plasticizer to improve the dispersion of AiBMP within the matrix. The good char charming ability of phenolphthalein itself and improved dispersion of AiBMP make the TPEE composites achieve both satisfying flame retardancy and high mechanical properties.

Electron attachment to the 3-benzelidenephthalide and phenolphthalein molecules and decay channels of their molecular anions were investigated by means of dissociative electron attachment spectroscopy and electron transmission spectroscopy. Interpretations of these experimental data were supported with UV-spectroscopy and density functional theory calculations. The average electron detachment times for the long-lived molecular anions of 3-benzelidenephthalide and phenolphthalein were measured to be 150 µs at 120 °C and 560 µs at 190 °C, respectively. The long-lived molecular anions of phenolphthalein are ascribed to an isomer formed by ring opening. The present results suggest that, opposite to phenolphthalein, polymeric materials based on 3-benzylidenephthalide cannot be switched to a high conductive state due to different mechanisms of stabilization of their long-lived molecular anions. [ABSTRACT FROM AUTHOR]

The carbonation action in concrete, in which carbonation reactions transform calcium hydroxide into calcium carbonate, is considered as a multi-phase physico-chemical process. Generally, carbonation in the cementitious composites has negative effects on the protection of reinforced bars due to the accelerated corrosion problem. The investigation of the carbonation degree is, therefore, necessary to evaluate the carbonation influence on the reinforced cementitious composites. In the present paper, experimental techniques to measure the carbonation degree in concrete are reviewed, including both qualitative and quantitative methods. It should be noted that, while qualitative technique focuses on the alterations in the concrete pore solution alkalinity which reflects the carbonation depth through the pH indicator, most quantitative methods could provide accurate determination of the CO2 penetration capacity during the carbonation process. The method used, for the practical phase, depends on the purpose of the carbonation degree measurement. [ABSTRACT FROM AUTHOR]

Poly(arylene ether nitrile) (PEN) is a class of high‐performance engineering plastics of poly(arylene ether) with cyano groups as side groups, which can get improved thermal, mechanical, and electrical properties through simple molecular structure design. In this work, a series of PEN (BPA/PP based PEN) copolymers were synthesized with varying amounts of phenolphthalein and bisphenol A. The influence of the copolymer molecular structure variations on the thermal, mechanical, and dielectric properties of PEN copolymer films was investigated. The results demonstrated that the BPA/PP based PEN copolymer films have great mechanical properties and low dielectric constant, as well as enhanced thermal properties. The highest 5% weight loss temperature of 494.9°C was obtained by PEN‐B7P3, while the highest glass transition temperature of 238.6°C was obtained by PEN‐B3P7. Porous BPA/PP based PEN films prepared by non‐solvent induced phase separation (NIPS) exhibited satisfactory mechanical properties and the highest tensile strength of 9.4 MPa was achieved. Moreover, the introduction of the phenolphthalein structure into the PEN molecular chain can improve the heat resistance of the PEN copolymers without deteriorating the dielectric properties, which gives the copolymers great potential as candidates for applications in flexible electronics and wireless communication. [ABSTRACT FROM AUTHOR]

The formation of the inclusion complex between β-cyclodextrin (CD) and phenolphthalein (PP) was investigated by means of UV–Vis and FT-IR spectroscopies. The thermodynamic parameters were calculated in the absence and presence of LiI, KI, NaI and CsI iodide salts. The enthalpy change during the formation was found to be negative for all solutions with iodide salts. The enthalpy change was found to decrease in the sequence no salt > NaI > KI> CsI > LiI. Moreover, it was observed that with increasing salt concentration enthalpy decreases monotonically. The interaction between the two molecules was mostly attributed to hydrogen bonding and Van der Waals interactions. Thermodynamic properties revealed that electrostatic forces also contribute when LiI is present in solutions. A molecular docking study was performed to elucidate the docking between phenolphthalein and cyclodextrin. The FT-IR spectra of CD, PP and the CD–PP complex were recorded to establish the formation of the inclusion complex. Semi-empirical and DFT methods were utilized to study theoretically the complexation process and calculate the IR vibrational spectra. The adequate agreement between theoretical and experimental results supports the proposed structural model for the CD–PP complexation. [ABSTRACT FROM AUTHOR]

Copyright of Plastics Science & Technology / Suliao Ke-Ji is the property of Plastics Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The detection of blood at a crime scene can yield great progress for an investigation. The presence of the bodily fluid can lead to the knowledge of whether the blood is in fact human, the amount of people that were present at the scene, and lead to DNA analysis being done and obtaining the identity of which the blood belongs to. A component in blood, hemoglobin, can break down hydrogen peroxide, making the protein a great focus for presumptive blood tests. For this experiment, a few household chemicals were used to test their ability to tamper with a color indicator Phenolphthalein Test. If the swab turned pink rapidly, this meant the stain came back positive for blood. If no color change occurred, the test could not detect if the substance swabbed was blood. Results obtained showed that household products with certain chemicals and percentage of said chemicals can be used denature the composition of hemoglobin in bloodstains. [ABSTRACT FROM AUTHOR]

Triads L–SNP–L, containing two ligands, phenolphthalein or 1,3,5,7-tetramethyl-8-(4-hydroxyphenyl)-4,4-difluoro-4-boron-3a,4a-diazaindacene (BODIPY), axially bound to Sn(IV)octaethylporphyrinate, were synthesized. The sensitivity of the obtained triads to changes in the acidity of the medium has been studied. Photoexcitation of the BODIPY-SnP-BODIPY triad leads to photoinduced energy transfer from the BODIPY donor fragments to the porphyrinate acceptor. When the triad is excited at the wavelength λexc = 490 nm, in addition to BODIPY fluorescence, fluorescence sensitized by the porphyrin fragment is recorded, and when the triad is excited at a wavelength λexc = 400 nm, porphyrinate fluorescence flares up compared to initial SnP. In the triad with phenolphthalein molecules, the fluorescent properties of both the ligand and porphyrinate are quenched, however, sensitivity to changes in the solution pH increases. [ABSTRACT FROM AUTHOR]

Byline: M. S. Javed, M. Amir, A. Amjad, M. Shah, M. J. Anwar and F. Ahmad Key words: INTRODUCTION Evolutionary spin and industrial dawn influenced human behaviour approaching processed foods, [...]

Fuel adulteration and cross-contamination lead to low-quality fuel products and loss of taxes. It is essential to develop methods of marking, identifying and monitoring tax classification of petroleum products in the market. In this work, a method for sensitive and fast detection of gasoline marker using paper-based platform and a smartphone camera detection are developed. A common dye, phenolphthalein (PhP), is used as a colorless dye marker in commercial gasoline. The color was developed by the interaction of PhP with NaOH on filter paper strips and evaluated by CMYK color systems. The newly developed counter-flowing technique, in which a gasoline sample containing PhP and NaOH solution are allowed to travel on a filter paper strip from the opposite end, gives the naked eye detection of PhP as low as 1 ppm with the limit of detection for a smartphone camera of 0.31 ppm. The high sensitivity is attributed to the preconcentration derived from accumulation of PhP at the immiscible liquid interface. The counter-flowing method can thus be a new facile analytical technique for enhancing chemical detection sensitivity.

Copyright of Meandros Medical & Dental Journal is the property of Galenos Yayinevi Tic. LTD. STI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

4-(2-(2,4-Dinitrophenyl) hydrazone) methyl)-2 methoxy phenol (IND-X) and 4-(2-(2, 4-dinitrophenylhydrazono) methyl) benzene-1,3-diol (IND-Y) were synthesised by condensation reactions with 2,4-dinitrinophenylhydrazine and were observed to possess acid-base indicator properties. The study was conducted to explore and verify their use in different analytical situations and, consequently, validate them. Analysis of their use in acid-base titrations between strong acids/strong bases and weak acids/strong bases as well as pharmaceutical applications in the assay of ibuprofen pure powder and batch of ibuprofen tablets (400 mg) using standard methods in the British Pharmacopoeia (2020) was all considered. The validations were performed by the International Conference on Harmonisation of Technical Requirements for the registration of Pharmaceuticals for Humans Q2 (R1) guidelines. The outcomes were statistically compared with existing conventional analytical approaches. Titrimetric data obtained were analyzed statistically by Student's t-test and one-way ANOVA at a 95% confidence level. IND-X and IND-Y were shown to be similar in behaviour to phenolphthalein, methyl orange, and methyl red as visual indicators after preliminary evidence of sharp colour changes in acid, alkaline, and neutral pH solutions. The use of the two indicators in the assay of ibuprofen powder and tablets has also been established. The validation parameters considered were found to be consistent with respective acceptance criteria for analytical purposes. IND-X and IND-Y are therefore proposed as alternative acid-base indicators to methyl red, methyl orange, and phenolphthalein for routine volumetric analysis in students' laboratory experiments. They also serve as alternative indicators to phenolphthalein for the titrimetric analysis of ibuprofen-based samples and products. [ABSTRACT FROM AUTHOR]