Improvement of Gel Quality of Squid (Dosidicus gigas) Meat by Using Sodium Gluconate, Sodium Citrate, and Sodium Tartrate

In order to improve the quality of squid surimi products, squid surimi gels were prepared using several types of organic salts under two heating conditions to study the effects of organic salts on squid gel properties. Compared with the NaCl group, organic salts reduced the solubilization capacity of myofibrillar protein, and significant (p < 0.05) decreases in the breaking force, breaking distance, texture, and water-holding capacity of the gel were observed in the sodium gluconate group, while significant (p < 0.05) increases in the breaking force, breaking distance, texture, and water-holding capacity of the gel were observed in the sodium citrate and sodium tartrate groups. Although the mixed addition of NaCl and organic salt improved surimi gel quality, the effective improvement was still lower than that of only organic salt. Rheological properties indicated that sodium citrate and sodium tartrate had high viscoelasticity. The squid surimi gel prepared by direct heating exhibited better properties than gels prepared by two-step heating. The chemical force of squid gel prepared with sodium citrate and sodium tartrate formed a stronger matrix than the gels prepared with other salts. For color, the addition of sodium citrate resulted in an undesirable color of squid surimi gels, while the addition of sodium tartrate improved the whiteness of the surimi gel. The results showed that the quality of surimi gel was dependent upon the choice of heating method and the types of salt used. Sodium citrate and sodium tartrate could significantly improve the gel properties of squid surimi. This study provides reliable guidance for improving the overall quality of squid surimi gels.

Preparation of Graphene/MoS2 Composite for Detection of Dopamine

A new composite of graphene/MoS2 is synthesized by co-exfoliation of graphite and MoS2 in isopropanol (IPA) using the organic salt potassium sodium tartrate as the assistant. The composite is characterized by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and Raman spectra. The results of TEM, XPS, and Raman spectra all illustrate that the graphene/MoS2 composite has been synthesized successfully. Furthermore, the composite is modified on glassy carbon electrode to fabricate a sensor to detect dopamine (DA). The sensor shows two linear detection ranges for DA. One is 1-45 μM and the other is 45-120 μΜ. The detection limit of the sensor (S/N=3) is 0.76 μM.

On the Miscibility of Nematic Liquid Crystals with Ionic Liquids and Joint Reaction for High Helical Twisting Power Product(s)

Mixtures of nematic liquid crystals (LCs) with chiral ionic liquids (CILs) may find application as active materials for electrically driven broadband mirrors. Five nematic liquid crystal hosts were mixed with twenty three ionic liquids, including chiral ones, and studied in terms of their miscibility within the nematic phase. Phase diagrams of the mixtures with CILs which exhibited twisted nematic phase were determined. Miscibility, at levels between 2 and 5 wt%, was found in six mixtures with cyanobiphenyl-based liquid crystal host—E7. On the other hand, the highest changes in the isotropization temperature was found in the mixtures with isothiocyanate-based liquid crystal host—1825. Occurrence of chemical reactions was found. A novel chiral binaphtyl-based organic salt [N11116][BNDP] was synthesized and, in reaction to the 1825 host, resulted in high helical twisting power product(s). Selectivity of the reaction with the isothiocyanate-based liquid crystal was found.

Control of the Optical and Physical Characteristics of Conjugated Polyelectrolytes in the Solution and Solid Phase

<p>Conjugated Polyelectrolytes (CPEs) are a branch of conducting polymers that combine the electronic and solution processability of conjugated polymers (CPs) with the ionic and self-assembling nature of polyelectrolytes. These systems have been shown to exhibit high sensitivity with changes in aggregation state and optical character dependant on the local environment. The ionic character of the CPEs can be used as scaffolds for post-synthetic alterations allowing for control of the optical and physical characteristics. In this thesis, the control of the optical and physical characteristics of the conjugated polyelectrolytes (CPEs) sodium poly[2-(3-thienyl)ethoxyl-4-butylsulfonate] (PTEBS) and poly(9,9-bis[6-(N,N,N-trimethylammonium)hexyl]fluorine-co-altphenylene] (FPQ-X, where X denotes the various counter-ions of the polymers) is investigated though the addition of various extrinsic ions to dilute solutions and concentrated solutions used for film casting, with the main focus being in the solution phase behavior. The CPE characteristics were studied primarily through UV/Vis absorption and fluorescence spectroscopy coupled with dynamic light scattering and surface tension techniques. Controlling the solution phase characteristics of the CPE was investigated through a study of through of solvent composition effects, monovalent and divalent ion addition, organic salt addition, and surfactant additions to dilute aqueous solutions of the CPEs. Solvent composition effects were shown to result in fluorescence enhancement with changes in the polarity of the solvent, while the addition of monovalent and divalent ions was shown to induce fluorescence quenching through ionic strength, ion condensation, and cross-linking of CPE molecules dependant on the concentration and valency of the metal ion. Organic salt additions of a range of concentrations were shown to result in both concentration and alkyl chain length dependant fluorescence intensity enhancements with little changes in the particle size of aggregates in solution. The lack of change in particle size suggested that the effects were localized to the aggregate surface with the size of the organic salt inducing a steric prying effect on the CPE aggregate. A proposed model of this was created to this effect. Large changes in the optical and physical characteristics of the CPEs were found with addition of surfactants to the CPE solutions. Fluorescence quenching and enhancements, particle size increases and decreases, and absorption hypsochromic shifts have been noted, with surfactant structure and concentration dependence. The resulting effects are shown to be hydrophobically, electrostatically, and self-assembly driven. Concentration control of the CPE aggregate size and optical characteristics is completed with surfactant micelles being noted at pre-CMC concentrations within the solutions. A model of interactions at the various concentration levels of surfactant has been developed explaining these results. Transferring this system to the solid state has been shown to exhibit both bathochromic and hypsochromic shifts in absorption and have two optically active phases. The dual phase absorption and emission was attributed to a CPE-surfactant complex where the CPE backbone and surfactant self assemblies result in lamellar type structures within the cast films. The optical overlap of the emission and absorption of the CPEs used was also shown to be favorable for FRET based transfer from FPQ-X to PTEBS. Films created by the layer-by-layer technique showed FRET based signal of PTEBS via excitation of FPQ-Br showing effective FRET based energy transfer between the two species. The absorption signatures of the films with multiple layer-by-layer processes showed that the films do not result in unique layers but rather interdigitated mixtures within the film. Proof of concept P3HT with DOD addition OFET devices were then created in the attempt to alter the electrode potentials using mobile ions. The devices were found to be less efficient than that of the controls due to the disruption of self assembled structures within the devices hampering electron movement.</p>

Control of the Optical and Physical Characteristics of Conjugated Polyelectrolytes in the Solution and Solid Phase

<p>Conjugated Polyelectrolytes (CPEs) are a branch of conducting polymers that combine the electronic and solution processability of conjugated polymers (CPs) with the ionic and self-assembling nature of polyelectrolytes. These systems have been shown to exhibit high sensitivity with changes in aggregation state and optical character dependant on the local environment. The ionic character of the CPEs can be used as scaffolds for post-synthetic alterations allowing for control of the optical and physical characteristics. In this thesis, the control of the optical and physical characteristics of the conjugated polyelectrolytes (CPEs) sodium poly[2-(3-thienyl)ethoxyl-4-butylsulfonate] (PTEBS) and poly(9,9-bis[6-(N,N,N-trimethylammonium)hexyl]fluorine-co-altphenylene] (FPQ-X, where X denotes the various counter-ions of the polymers) is investigated though the addition of various extrinsic ions to dilute solutions and concentrated solutions used for film casting, with the main focus being in the solution phase behavior. The CPE characteristics were studied primarily through UV/Vis absorption and fluorescence spectroscopy coupled with dynamic light scattering and surface tension techniques. Controlling the solution phase characteristics of the CPE was investigated through a study of through of solvent composition effects, monovalent and divalent ion addition, organic salt addition, and surfactant additions to dilute aqueous solutions of the CPEs. Solvent composition effects were shown to result in fluorescence enhancement with changes in the polarity of the solvent, while the addition of monovalent and divalent ions was shown to induce fluorescence quenching through ionic strength, ion condensation, and cross-linking of CPE molecules dependant on the concentration and valency of the metal ion. Organic salt additions of a range of concentrations were shown to result in both concentration and alkyl chain length dependant fluorescence intensity enhancements with little changes in the particle size of aggregates in solution. The lack of change in particle size suggested that the effects were localized to the aggregate surface with the size of the organic salt inducing a steric prying effect on the CPE aggregate. A proposed model of this was created to this effect. Large changes in the optical and physical characteristics of the CPEs were found with addition of surfactants to the CPE solutions. Fluorescence quenching and enhancements, particle size increases and decreases, and absorption hypsochromic shifts have been noted, with surfactant structure and concentration dependence. The resulting effects are shown to be hydrophobically, electrostatically, and self-assembly driven. Concentration control of the CPE aggregate size and optical characteristics is completed with surfactant micelles being noted at pre-CMC concentrations within the solutions. A model of interactions at the various concentration levels of surfactant has been developed explaining these results. Transferring this system to the solid state has been shown to exhibit both bathochromic and hypsochromic shifts in absorption and have two optically active phases. The dual phase absorption and emission was attributed to a CPE-surfactant complex where the CPE backbone and surfactant self assemblies result in lamellar type structures within the cast films. The optical overlap of the emission and absorption of the CPEs used was also shown to be favorable for FRET based transfer from FPQ-X to PTEBS. Films created by the layer-by-layer technique showed FRET based signal of PTEBS via excitation of FPQ-Br showing effective FRET based energy transfer between the two species. The absorption signatures of the films with multiple layer-by-layer processes showed that the films do not result in unique layers but rather interdigitated mixtures within the film. Proof of concept P3HT with DOD addition OFET devices were then created in the attempt to alter the electrode potentials using mobile ions. The devices were found to be less efficient than that of the controls due to the disruption of self assembled structures within the devices hampering electron movement.</p>

Pharmaceutical organic salt: Disordered crystal structure of levofloxacin with γ-resorcylic acid

This study reports an organic salt prepared from an antibacterial drug, levofloxacin and antioxidant γ-resorcylic acid. A simple preparation method leads to a crystal with disordered structure. The idea is to prepare an organic salt comprising of pharmaceutically acceptable acidic and basic components. The salt is characterised by IR, solid state NMR, and single crystal XRD. Crystal data for C25H26N3O8F: triclinic, space group P-1 (no. 2), a = 7.0037(8) Å, b = 12.764(3) Å, c = 13.909(3) Å, α = 104.821(4)°, β = 92.039(4)°, γ = 95.334(4)°, V = 1194.6(4) Å3, Z = 2, T = 296(2) K, μ(MoKα) = 0.113 mm-1, Dcalc = 1.433 g/cm3, 16879 reflections measured (5.048° ≤ 2Θ ≤ 54.186°), 5139 unique (Rint = 0.0663, Rsigma = 0.0975) which were used in all calculations. The final R1 was 0.1121 (I>2σ(I)) and wR2 was 0.2505 (all data). SC-XRD analysis shows that the crystal packing is stabilized by strong H-bonding of type N-H···O and comparatively weak interactions of type C-H···O, C-H···π and off-set π···π stacking.