Potassium Poly Vinyl Sulfate Research Articles

Polyaniline microspheres using potassium polyvinyl sulfate as template for large-area broadband electrochromic device with large infrared emissivity variation

In the development of polyaniline (PANI) based large-area broadband electrochromic devices, we employed a controlled deposition process using potassium polyvinyl sulfate (PVSK) as a template to regulate the morphology of PANI. This resulted in consistent spherical particle morphology and heightened electrochemical activity in PVSK-PANI films. The simple structure of PVSK, coupled with its similar IR absorption to polyethylene and sulfuric acid, mitigated any detrimental effects on the broadband electrochromic properties. In small-area (2 × 2 cm²) PVSK-PANI electrochromic devices, we observed maximum emissivity changes of 0.47, 0.51, and 0.49 in the 3-5 μm, 8-14 μm, and 2.5-15 μm ranges, respectively. Expanding our approach to large-area devices (20 × 20 cm2), we achieved even more promising results. The PVSK-PANI based electrochromic devices achieved maximum emissivity changes of 0.55, 0.46, and 0.46 within the same spectral ranges of 3-5 μm, 8-14 μm, and 2.5-15 μm, respectively. Notably, these large-area electrochromic devices demonstrated a remarkable capacity to modulate infrared temperature by up to 10.4 °C at a background temperature of 70 °C.

Study on the relationship between crosslinking degree and properties of TPP crosslinked chitosan nanoparticles

In order to reveal the relationship between the degree of crosslinking and the properties of chitosan nanoparticles, a potassium polyvinyl sulfate (PVSK) titration method was established for the determination of free amino group in chitosan, which showed that there was a window effect in the crosslinking degree and particle size of three kinds of molecular weight chitosan cross-linked by different content of tripolyphosphate (TPP), and the nanoparticles with moderate crosslinking degree were smaller. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) showed the moderate degree of cross-linking nanoparticles had strong antibacterial properties. IR analysis showed that the interaction between chitosan nanoparticles with different crosslinking degree and TPP were different. X-ray diffraction analysis showed that the cross-linked chitosan nanoparticles were amorphous. Above all, the crosslinking degree of TPP cross-linked chitosan nanoparticles was related to the particle size and antibacterial properties.

Effect of Potassium Polyvinyl Sulfate on the Separation of Alkali Metal and Alkaline Earth Metal Ions by Capillary Zone Electrophoresis

Effect of Potassium Polyvinyl Sulfate on the Separation of Alkali Metal and Alkaline Earth Metal Ions by Capillary Zone Electrophoresis

Ink-jettable paper-based sensor for charged macromolecules and surfactants

The use of metachromatic dye-based formulations for the preparation of inkjettable prototype indicators suitable for the detection of charged macromolecules, surfactants or other low molecular weight molecules was investigated. Such indicators were based on the use of metachromatic o-toluidine blue (OTB) that undergoes a characteristic change in color (from blue to pink) upon interaction with anionic macromolecules. When applied onto absorbing substrates such as paper and paperboard, solutions containing OTB and the same dye in the presence of potassium polyvinyl sulfate (KPVS), proved to indicate negatively charged polymers and cationic surfactants. The colorimetric responses suggest a detection limit and sensitivity both are in the order of 1mM of charged species but can be further improved. Interactions between active species in the indicators and some of the additives in inkjettable formulations (surfactant and humectants) interfered with the mechanism by which an OTB/KVPS-based system work only to a minor degree and could be overcome by priming the substrate. An OTB-based system was formulated into an inkjettable formulation that, once applied to a substrate, was showed to indicate charged polymers and surfactants. This concept has the potential for sensing/indication of other charged macromolecules, such as carboxylates and polyphosphates, which are relevant in biomedical (e.g. fouling due to microbial activity), packaging applications (e.g. migration or release of compounds, food spoilage), microfluidic devices or a simple dipstick application to indicate the presence of charged components.

Room-Temperature Fluorescence Lifetime of Pseudoisocyanine (PIC) J Excitons with Various Aggregate Morphologies in Relation to Microcavity Polariton Formation

The results of room-temperature fluorescence lifetime measurements are reported for the excitation of J aggregates (Js) of pseudoisocyanine chloride (PIC-Cl) prepared in potassium polyvinyl sulfate (PVS) polymer thin films, their aqueous solutions, and NaCl aqueous solutions. Variations of the microscopic morphologies of the aggregates were investigated. The results show that fluorescence decay features correlated to the morphology change. The observed fluorescence lifetime and quantum efficiency of PIC J aggregates (PIC-Js) in a NaCl aqueous solution were 310 ps and 28%, respectively. The lifetime of the fibril-shaped macroaggregates prepared in PVS thin films was below the instrumental time resolution of 5 ps, and the efficiency decreased to below 3%. The results indicate that PIC-Js prepared with PVS polymers have an increased nonradiative contribution to the excitation deactivation process. In particular, macro-Js with isolated fibril-shaped structures revealed nonradiative pathway(s) that are closely associated to the specific packaging morphology of the constituent meso-Js. The possibility of a destructive effect on the formation of cavity-polaritons is also discussed.

Streaming potential sensing in paper-based microfluidic channels

Streaming potential measurements detected the presence of adsorbed polyvinylamine or potassium polyvinylsulfate in paper-based microfluidic devices. Capillary driven flow in filter paper induced measurable potentials in the range −80 to +80 mV. The magnitude and polarity of the measured potentials were sensitive to the presence of adsorbed polymer. In a second example, paper treated with BSA gave a positive streaming potential at pH 3.7, below the isoelectric point of BSA, and a negative potential at high pH. We propose that streaming potential may provide an electronic interface for paper-based biosensors.

Key considerations in the determination of polyelectrolyte concentration by the colloidal titration method

Medium or high charge density cationic polyelectrolytes are frequently used for water treatment. In the papermaking wet-end they are used as retention agents or as flocculating aids. Negative polyelectrolytes that enter the papermaking system increase the demand for cationic polyelectrolytes. Polyelectrolyte concentration can be determined by the colloidal titration method, using either of two options for detecting the endpoint: i) visual observation or spectrophotometric determination of the colour change of an indicator, or ii) streaming current measurement. This work discusses the best conditions for the application of the titration using spectrophotometric measurement for the end point detection. Poly-diallyldimethylammonium chloride was used as the cationic polyelectrolyte, potassium polyvinyl sulphate as the negative polyelectrolyte, and o-toluidine blue as the positive indicator dye. The polyelectrolyte concentration range, interference from the metal ions affecting the indicator color change, the optimal indicator concentration to avoid precipitation problems, and the effect of adding a surfactant to the indicator solution were also considered. Titration curves were analyzed and optimized. Under these conditions the technique provided results with acceptable precision.

지시약 적정법 및 분광광도법에 의한 양이온 고분자 전해질의 전해밀도 정량

Polyelectrolyte titration, which was called colloid titration is based on the stoichiometric reaction between oppositely charged polyelectrolytes, This can be used, for instance, to determine the charge density of a cationic polyelectrolyte, using an anionic polyelectrolyte of known charge density, such as potassium polyvinyl sulfate (PPVS). The technique requires a suitable method of end-point detection and there are several possibilities. In this work, two methods have been investigated: visual titrimetry based on the color change of a cationic dye (o-toluidine blue, o-Tb) and spectrophotometry based on the absorbance change corresponding to the color change of the same dye. These have been applied to several cationic polyelectrolytes with different charge density and molecular weight. In all cases, the cationic charge was due to quaternary nitrogen groups. In the case of cationic dye, it was shown that the sharpness depends on the charge density of cationic polyelectrolyte. With the polyelectrolytes of lower charge density, the binding to PPVS is weaker and binding of the dye to PPVS can occur before all of the polyelectrolyte charge has been neutralized. However, by carrying out titrations at several polyelectrolyte concentrations, good linear relationships were found, from which reliable charge density values could be derived. Effects of pH and ionic strength were also briefly investigated. For cationic polyelectrolytes (copolymers of acrylamide and dimethylaminoethy] acrylate), there was some loss of charge at higher pH values, probably as a result of hydrolysis. Increasing ionic strength causes a less distinct color change of o-Tb, as a result of weaker electrostatic interactions.

Mono-channel taste sensor using LB film

Mono-channel taste sensor using polyion-complex LB file is described. The sensing film deposited on the silver plate was dioctadecyldimethylammonium bromide (DOABr) combined by potassium polyvinyl sulfate (PVSK) as an under layer. New method was developed by detecting both parameters of membrane potential change and time response for titration. Five basic taste substances could be experimentally discriminate by these parameters.

Charge determination of synthetic cationic polyelectrolytes by colloid titration

The stoichiometric interaction between oppositely charged polyelectrolytes forms the basis of the technique of colloid titration. This can be used, for instance, to determine the charge density of a cationic polyelectrolyte, using an anionic polyelectrolyte of known charge density, such as potassium polyvinyl sulphate (PPVS). The technique requires a suitable method of end-point detection and there are several possibilities. In this work three methods have been investigated: visual observation of the colour change of a cationic dye ( o-toluidine blue), spectrophotometric determination of the colour change of the same dye, and electrokinetic detection of charge neutralisation, using a streaming current detector. These have been applied to a range of cationic polyelectrolytes, with different charge densities and molecular weights. In all cases, the cationic charge was due to quaternary nitrogen groups. In the case of the cationic dye, it was shown that the sharpness of the colour change depends on the charge density of the cationic polyelectrolyte. With lower charge density materials the binding to PPVS is weaker and binding of the dye to PPVS can occur before all of the polyelectrolyte charge has been neutralised. However, by carrying out titrations at several polyelectrolyte concentrations, good linear relationships were found, from which reliable charge density values could be derived. The streaming current method avoids the problem of competitive interaction of PPVS with o-toluidine blue and gives quite sharp transitions at the isoelectric point, although there was some dependence on polyelectrolyte charge density. This method gave good agreement with charge densities derived from the spectrophotometric technique. Effects of pH and ionic strength were also briefly investigated. For most of the cationic polyelectrolytes, there was some loss of charge at higher pH values, probably as a result of hydrolysis. Increasing ionic strength causes a less distinct colour change of o-toluidine blue, as a result of weaker electrostatic interactions.

The Use of Thermodynamics for the Indirect Determination of Neutral Surfactants Activities in Mixtures of Potassium Polyvinyl Sulfate (PVSK), Dodecyltrimethylammonium Bromide (DTABr), andN-Dodecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (SB12)

Mixtures of zwitterionic and cationic surfactants were studied in the presence of an anionic polyelectrolyte. We usedN-dodecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (SB12), dodecyltrimethyl ammonium bromide (DTA+Br−), and polyvinyl sulfate (potassium salt) (PVS−K+). The composition of the system was determined by measuring the activity of DTABr with an ion-selective electrode, and deducing the activity of SB12 from thermodynamic equations. This method provides information about the distribution of all species (activities of both surfactants and composition of the micelles), by experimental determination of only one quantity. SB12 affected the adsorption of DTABr onto PVSK.

Protective effects of dextran sulfate and polyvinyl sulfate against acute toxicity of paraquat in mice

The protective effects of dextran sulfate (SDS) and potassium polyvinyl sulfate (PPS) against the acute toxicity of paraquat (PQ) in mice were studied. The survival rates of mice treated with SDS (2000 mg/kg) or PPS (2000 mg/kg) immeadiately after PQ ingestion (200 mg/kg) were 100% or 100%, respectively. When treated with SDS (2000 mg/kg) or PPS (2000 mg/kg) 15 or 30 min after PQ ingestion (200 mg/kg), the survival rates were 83% or 67% for SDS-treated groups and 67% or 33% for PPS-treated groups, respectively. Treatment with SDS (2000 mg/kg) or PPS (2000 mg/kg) immediately after oral administration of PQ (200 mg/kg) increased the fecal excretion of PQ, decreased the urinary excretion of PQ and decreased the contents of PQ in the lung, liver and kidney. Such effects of SDS and PPS were reduced in the treatment with these drugs at 15 min after PQ. The in sistu small intestinal absorption of PQ was significantly reduced in the presence of SDS or PPS. The binding of PQ to SDS or PPS was determined by an ultrafiltration method. These results indicate that SDS and PPS inhibit the gastrointestinal absorption of PQ on the basis of the increased intestinal transit of PQ and the binding of PQ to the drugs, resulting in the protective effectiveness of SDS and PPS on the acute toxicity of PQ.

The effect of polycations on the inhibitory action of antithrombin iii on thrombin in the absence and presence of polyanions

Polycations of biological and synthetic origin inhibit the action of AT III on thrombin activity. The effect is more pronounced with increasing molecular weight of branched polycations.Quantitatively protamine causes the same effect as quaternized polycations on the basis of charge equivalence. The accelerating effect of heparin or potassium polyvinylsulfate for the inhibitory action of AT III is abolished by charge equivalent amounts of polycation. The observations indicate a dual action of polycations in the heparin/AT III/thrombin interaction.

The role of surface charge on the accelerating action of heparin on the antithrombin III-inhibited activity of alpha-thrombin.

We have compared surface charge and the surface charge density on the polyanions heparin and potassium polyvinyl sulfate (KPVS), as well as on hydrolyzed heparin and KPVS, with their accelerating effect on the inhibitory action of antithrombin III on thrombin. Polyelectrolyte titration of thrombin with KPVS or heparin at pH 7.4 clearly indicates an electrostatic interaction. In contrast, at the same pH no electrostatic interaction is observed between polyanions and antithrombin III. KPVS accelerates the inhibitory action of antithrombin III to the same extent as heparin on the basis of charge equivalence. Heparin and KPVS with a mean distance between two charged centers of less than 0.75 and 0.95 nm, respectively, accelerate strongly whereas hydrolysates with lower charge densities are far less active. The following observations are indicated. Intramolecular neutralization of oppositely charged residues occurs within thrombin, antithrombin III, and partially hydrolyzed heparin. Heparin acts on the antithrombin III-thrombin reaction through cooperative electrostatic binding to thrombin and nonelectrostatic interaction with antithrombin III. This indicates a quasi-catalytic action of the polyelectrolyte. Hydrolysis of only a few N-sulfate residues within the heparin molecule decreases the linear surface charge density to such an extent that the accelerating action is drastically reduced. The loss of accelerating capacity agrees with the sudden loss of counterion condensation due to the decrease of the linear surface charge density beyond limits postulated by Manning in a theory of polyelectrolytes.

Endocytic mechanism of macrophages to anionic foreign substances.

To study the non-immunogenic defense mechanism on organisms against foreign substances, reactions of cells to anionic colloidal particles were observed on macrophages from rat peritoneal cavity and liver tissues. As the non-antigenic anionic particles, iron colloids obtained by coating ferric hydroxide colloidal particles with potassium polyvinyl sulfate or chondroitin sulfate were used. Observations revealed that peritoneal macrophages and Kupffer cells develop surface receptors having specific affinity to anionic particles by which the cells adsorb them on the surface and internalize them into the cytoplasm for decomposition or detoxication. The other general somatic cells did not have any such receptors and were unable to take up the foreign particles having a negative surface charge.

Charge determination of proteins with polyelectrolyte titration.

A recently developed photometric version of polyelectrolyte titration was applied for the determination of the number of charged residues on globular proteins. Based on the observation that oppositely charged polyelectrolytes form, in general, stoichiometric polyelectrolyte complexes, the protein solutions were incubated in excess with an oppositely charged polyelectrolyte, and the residual amount was back-titrated using o-toluidine blue for end point detection. It was found that within the range pH 2 to pH 9 the interaction of the polyelectrolytes, potassium polyvinylsulfate, polydiallylammonium chloride, and N-methylglycolchitosan iodide, with various proteins of known amino acid composition (ribonuclease A, trypsin, chymotrypsin A, pepsin, cytochrome c) occurs stoichiometrically through 1:1 ion pair interaction, irrespective of the spatial distribution of the interacting ionic sites. The close correspondence between the experimental data for the net charge and the calculated balance of ionized residues for the proteins at a given pH indicates that in the native structure of these proteins oppositely charged ionic functions are largely neutralized by the formation of intramolecular salt linkages. It is concluded that polyelectrolyte titration offers an easy access to the determination of the surface charge of proteins and other biopolymers. The data further support the notion of the importance of electrostatic cooperative interactions in biological systems.

A morphological study of ferritin synthesis in macrophages with ingested ferric hydroxide-potassium polyvinyl sulfate complexes.

A ferric hydroxide-polyvinyl sulfate colloidal solution (Fe-PVS), prepared by mixing potassium polyvinyl sulfate (PVSK) and ferric hydroxide colloidal solution was used to study ferritin synthesis in rat peritoneal macrophages. The colloidal particles had spherical electron opaque ferric hydroxide cores with diameters of about 250 nm surrounded by radially arranged fibrous PVS molecules. They also had strong negative electric charges. Fe-PVS particles injected into the peritoneal cavity were taken up by the macrophages then disintegrated rapidly. In the phagolysosomes the electron opaque ferric hydroxide cores of Fe-PVS were denuded of their PVS frames then decomposed into small 5-6 nm granules 24 to 48 h after injection. These small granules were released from the lysosomes into the hyaloplasm and the myelin figures were found in the lysosomal vacuoles. No reaccumulation of granules in lysosomes was found even 3 months later. The intracellular distribution of ferritin in macrophages demonstrated by the immunocytochemical method showed a pattern similar to that of the small granules formed by the disintegration of Fe-PVS. This means that in rat peritoneal macrophages that contain ingested Fe-PVS particles ferritin first is synthesized in phagolysosomes by the ferric hydroxide cores that conjugate with apoferritin or protein subunits then they are dispersed into the cytoplasm. Two possible pathways for the biosynthesis of ferritin are discussed.

A turbidimetric method for colloid titrations

Positive colloid solutions can be titrated with the polyanion potassium polyvinylsulfate with toluidine blue as indicator, but negative colloid solutions must be treated with an excess of the polycation polydiallyldimethylammonium chloride which is backtitrated with potassium polyvinylsulfate. By turbidimetry however, positive or negative colloid solutions can be directly titrated with, respectively, the polyanionic or polycationic titrant. Two methods, the construction and differential methods, can be used. The latter method is particularly useful when a flocculent precipitate appears during the titration.

A conductometric method for colloid titrations

A negative or positive colloid sample solution can be directly titrated, respectively, with a polycationic (poly-N, N-diallyldimethylammonium chloride) or polyanionic (potassium polyvinylsulfate) titrant to a conductometric end-point. With the conventional toluidine blue indicator method a positive colloid solution is titrated directly with a polyanionic titrant, but a negative colloid solution must be treated with an excess of a polycationic titrant, which is back-titrated with the polyanionic titrant. For positive colloid solutions, both indicator and conductometric methods are suitable; for negative colloids the conductometric method is preferable because of its constant titration vlues over a range of pH values.

Interaction between dyes and polyelectrolytes. I. Effect of polyelectrolytes on the reaction of methylene blue with 1‐benzyl‐1,4‐dihydronicotinamide

AbstractThe effect of polyelectrolytes on the reaction of methylene blue with 1‐benzyl‐1,4‐dihydronicotinamide was investigated. An accelerating effect was observed on addition of sodium polystyrenesulfonate of poly(potassium p‐styrenesulfonate). On the other hand, deceleration was observed on addition of potassium polyvinylsulfate. No appreciable effect was observed when sodium p‐toluenesulfonate or potassium chloride was used as an electrolyte. An obvious color change was observed when methylene blue is bound to these anionic polyelectrolytes. Some correlations with spectral change of methylene blue and acceleration or deceleration effect are discussed.