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Chiral selective adsorption of L-amino acid, tryptophan (Trp) was achieved using phospholipid membrane-coated porous polymer particles (PPPs). PPPs with numerous pores were prepared by in situ polymerization of divinylbenzene, and then coated with 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC, L-phospholipid) via the impregnation method. Elemental mapping of energy dispersive X-ray (EDX) analysis revealed that DPPC molecules were distributed to the surface and the inner part of PPPs, where almost all the DPPC molecules applied for impregnation were deposited on PPPs. The phospholipid membrane properties of DPPC-PPPs were characterized using the fluorescence probe 6-lauroyl-2-dimethylaminonaphthalene (Laurdan). The results show that DPPC-PPPs possessed a lipid membrane-like environment similar to pure DPPC liposomes, especially at temperatures below 35 °C. DPPC-PPPs slightly adsorbed L-Trp and D-Trp at 45 °C, while DPPC-PPPs significantly adsorbed L-Trp but not D-Trp at 30 °C: enantio excess (e.e.) was 75.0%. The time course of Trp adsorption was investigated: for both enantiomers, similar adsorption behaviors were observed for 30 h, thus suggesting surface adsorption onto DPPC-PPPs. L-Trp adsorption continued after 30 h, suggesting that L-Trp could be distributed in the inner part of DPPC-PPPs. Interestingly, the reused DPPC-PPPs featured improved adsorption performance, suggesting that the deposited DPPC membranes on PPPs could act as chiral selectors for L-Trp. The optical resolution of L-/D-Trp was performed using DPPC-PPPs, resulting in the e.e. of D-Trp was 60%. Thus, DPPC-PPPs have the potential of chiral selective adsorption of L-amino acid, which can be used as chiral separation materials.

Exosomes are the master transporters of genes, RNAs, microRNAs, proteins, and lipids. They have applications in major diseases, including cancer, cardiovascular diseases, neurological disorders, and diabetes mellitus. Delivery of the exosomes to recipient cells is governed by the functional heterogenicity of the tissues. Engineered exosomes are promising tools in tissue regeneration. In addition to their role as intracellular communication cargos, exosomes are increasingly primed as standard biomarkers in the progression of diseases, thereby solving the diagnostic dilemma. Futuristic empowerment of exosomes with OMICS strategy can undoubtedly be a bio-tool in translational medicine. This review discusses the advent transformation of exosomes in regenerative medicine and limitations that are caveats to broader applications in clinical use.

This study examined the adsorption of heavy metals and precious metals from aqueous solution by livestock biomass as biosorbents and their treatment effect with reducing chemicals. The adsorption of copper, lead and cadmium was carried out using sheep wool, sheep manure and sheep fat. The copper adsorption was highest among three biosorbents. Sheep wool was treated with an aqueous solution of Na2S, NaOH, NaHSO3, and NaBH4 to enhance the adsorption ability. The Na2S treatment of sheep wool dramatically enhanced the adsorption amount of Au(III) and Cr(III) and was several effective for Cu(II) and Cr(IV). All adsorption results were confirmed with the Langmuir isotherm model in the equilibrium and Pseudo-second order model in the kinetics. From the adsorption properties and ESCA analysis of sheep wool adsorbed each metal, it was confirmed that Au(III) interacted with thiol and amino groups, Cu(II) and Cr(III) with a carboxyl group, and Cr(VI) with the amino group of sheep wool.

Sheep wool as biosorbent materials was chemically modified by NaOH, Na2S, NaHSO3, and NaBH4 solution. The adsorption amounts of Au(III) were increased after the chemical treatment and the adsorption capacity of the chemically treated wool were performed in the following order; Na2S treated wool > NaBH4 treated wool > NaOH treated wool > NaHSO3 treated wool. Furthermore, sheep wool was modified by Na2S at different concentrations (0.002 – 0.1 M). The surface characterization is analyzed by Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The appropriate concentration of treatment was determined at 0.02 M and 0.05 M concentrations of Na2S. Sheep wool changed to a sheet-like structure after 0.05 M of Na2S treatment; however, it keeps fiber structure after treatment of 0.02 M of Na2S. The adsorption amounts of Cu(II) were increased after the Na2S treatment and amounts were performed in the following order; 0.05 M of Na2S treated > 0.02 M of Na2S treated > none treated wool. XPS analysis results indicated that the binding of copper ion to the sheep wool is attributed through the oxygen of carboxyl groups of the sheep wool. Gold was bound to the nitrogen of amino and sulfur of the thiol group was confirmed by XPS. Adsorption kinetics fitted well with a pseudo-second-order kinetic model. Langmuir isotherm model more fit with the experimental data than Freundlich isotherm model. In summary, Na2S treated sheep wool to be revealed as an effective low-cost biosorbent for removal of Au(III) and Cu(II).

Natural zeolite beads were prepared by encapsulating mesoporous zeolite into alginate beads via egg box method and its adsorption properties of Pb(II) ions were investigated in aqueous solution. Crystallinity and size reduction of natural zeolite were enhanced by mechanic modification of the ball milling process. FTIR and SEM-EDS analyses confirmed that mechanically modified zeolite particles were incorporated into alginate hydrogel. The highest adsorption amount of zeolite alginate beads was 87.47 mg/g after 20 h adsorption process. SEM-EDS result confirmed that the adsorption process has occurred on the surface of zeolite alginate beads. Adsorption kinetic data were fitted with Langmuir adsorption isotherm which showed that Pb2+ cation adsorbed into monolayers of adsorbent material. Moreover, we observed that calcium ion released after the Pb2+ adsorption process in the feed solution. Therefore, the adsorption mechanism of zeolite alginate beads explained by complex mechanisms including surface sorption and ion exchange of Pb2+ and Ca2+ in beads.

In this study, the structural characteristic and the adsorption properties of heavy metals on Mongolian natural minerals were investigated. The natural samples were confirmed as Heulandite group of Clinoptilolite type zeolite and clay sample that contains albite and quartz by X-ray diffraction analysis. According to BET surface analysis, natural zeolites have mesoporous type of pore. The results of adsorption study showed that adsorption ability of natural zeolite is high effective for lead ion in acidic aqueous solution and the order of heavy metal selectivity was Pb2+>>Zn2+>Cd2+. The adsorption performance of Arsenic(V) is significantly increased by modification with magnesium oxide on natural zeolite.

Microcapsules and porous polymer particles containing extractants, which are functional molecules to extract target ions or molecules by specific interaction using in solvent extraction process, are expected to be an effective separation medium of various substances from aqueous solution in hydrometallurgical process of harmful or valuable metals and in environmental protection processes from various pollutants. The preparation method, encapsulating materials and application area of these materials has been developed and extended in recent years. Recent topics of this field was been presented. The research on the polymeric particles for separation medium investigated by authors was introduced and showed the structural effect of the polymeric particles containing extractant on the separation performance of metal ion and chiral separation of amino acids by porous particles impregnated with phospholipids.

Chromium adsorption from the aqueous phase was evaluated using Mongolian sheep wool as a biosorbent. The wool was chemically treated with sodium sulfide to enhance the adsorption capacity. The surface of the wool was analyzed by SEM. EDX and FTIR were also used for the analysis of differences in the wool after chromium adsorption. Chromium was detected in the wool after adsorption by EDX analysis. FTIR data indicated the intensity change in amide A and amide I, which shows chromium may be adsorbed to the amino and carboxyl groups of the wool. The sodium sulfide treated wool showed better adsorption capacity of chromium(III) than the untreated wool. In the case of chromium(III), the adsorption amount increased with the pH increased, while for chromium(VI), the adsorption value increased with the pH decreased. Kinetic analysis of the adsorption indicated that the removal of chromium followed pseudo-second order kinetic model for the whole contact time range. Langmuir isotherm model was used for the analysis of adsorption equilibrium and the adsorption followed well Langmuir isotherm. This study demonstrates the sodium sulfide treated wool is an effective and low-cost biosorbent for heavy metal adsorption.

For the microcapsules preparation process, the mechanism is estimated by structure reformation during the preparation process since diameter and wall thickness drastically changed. Microstructures are recently studied by machine learning techniques. The Hough transformation algorithm is used by other researchers for the preparation of the microcapsules but it is difficult to determine the mechanism by using only a diameter change of the microcapsules. Therefore, one additional way to establish the mechanism is the analysis of the formation of the microcapsule structure. In this study, The Hough transformation algorithm was used for the image segmentation, the simple feature extractions were checked and the support vector machine and the k-nearest neighbors algorithm were used as classifiers in order to analyze the structure of the microcapsules which were prepared by solvent evaporation method from a solid in oil in water, S/O/W, emulsion system. The structural distribution was analyzed by the developed detection method. The microcapsules had a specific structural distribution which are monocore, multicore, and other aggregated structures. The structural distribution was changed by the preparation condition. The monocore structure was dominant by increasing in the amount of water soluble solid particles added in the organic phase.

Au(III) and Cu(II) adsorption from aqueous solution were carried out using sheep wools with chemical treatments, by NaOH, Na2S, NaHSO3, and NaBH4 aqueous solution. The fibrous wool was transformed into a film like structures after the chemical treatment using Na2S. The sheep wool and the chemically treated sheep wool adsorbed selectively Au(III) from Au-Cu binary aqueous solution and the presence of copper ion had no effect on the Au(III) adsorption. Au(III) adsorbed substantially at low pH range. The kinetic experimental data fitted well with the pseudo-second-order kinetic model and the adsorption amount of Au(III) increased with time and reached a plateau after 12 h. The kinetic analysis suggests that rate determining step of Au adsorption would be chemisorption due to the formation of a monolayer on the wool surface. Sheep wool is a low cost, eco-friendly material, and has a high capacity of adsorption, and could be used as a biosorbent for precious and heavy metals by modification of appropriate chemical treatment.

Silicon oxide thin films have been formed by use of the reaction between spin-coated silicone oil and ozone gas at atmospheric pressure and low temperature (250°C). Films formed at this temperature contained Si–OH bonds, owing to inadequate dehydration. To remove the Si–OH bonds at low temperature, the sample was dipped in ethanol at room temperature for 15 min then annealed on a hot plate at 250°C in methanol gas for 30 min. This treatment effectively dissociated the Si–OH bonds. It is believed the Si–OH bonds are replaced by Si-OCH3 bonds during the alcohol-assisted annealing. The leakage current of the metal-oxide-semiconductor after alcohol-assisted annealing was improved and the hysteresis width was reduced. This indicated that the number of trap sites owing to Si–OH bonds was reduced.

The arsenic contamination of groundwater in Uttar Pradesh State was first recognized in 2003 and is now seen at 20 Districts out of 70 Districts. University of Miyazaki has performed the arsenic mitigation project in Bahraich District, severest arsenic-affected one in the 20 Districts, from June 2008 until now, with JICA (Japan International Cooperation Agency). The integrated mitigation, such as the raising awareness of villager, installing of alternative water supply units and healthcare of arsenocosis patients, have been executed at the 2 villages. The symptom of the arsenocosis patients was not so severe, which will be, therefore, improved by drinking arsenic-safe water supplied through arsenic removal units, installed by this project. In this paper, following results is discussed for the situation and mechanism of arsenic contamination of groundwater, objected in connection with the installation of arsenic removal units: 1) Groundwater is almost contaminated with arsenic in deep tubewell (depth: about 30 m), but scarcely in shallow tubewell (depth: about 10 m); 2) Arsenic contaminated groundwater is under the reduced condition with the oxidized condition for no-arsenic contaminated groundwater; 3) Arsenic concentration shows almost linear correlation with concentrations of Fe2+ and -N; 4) Ground is composed of sand with high arsenic content at around 25 m depth; 5) Arsenic exists mainly in the phase of reducible fraction or weak acid soluble fraction but no oxidizable fraction in the ground.

宮崎県小丸川水系の渡川ダム，松尾ダムおよび下流の川原ダムの堆積土砂に含まれる難沈降性の微細粒子について，粒径および成分・鉱物組成分析し，各ダムの微細粒子に関する物理・化学的性状を解析した．長期濁水化の原因粒子となる難沈降性粒子の粒径は，平均2μmであり，形状は平板状であった．三つのダムの難沈降性粒子の成分組成はほぼ同一であり，鉱物の結晶形から推察すると，小丸川水系の松尾ダムおよび川原ダムにおける濁水化の懸濁粒子の起源は，渡川ダムの堆積土砂であると推察された．難沈降性粒子の沈降速度は極めて遅く，2mm/hr（5cm/day）程度であった．洪水等によって大量の堆積土砂が撹拌混合され，ダム内において難沈降性粒子が高濃度に浮遊懸濁した状態になった場合，重力沈降のみによる清澄化は極めて困難であることが示唆された．

長鎖アルキルアミンであるトリ-n-オクチルアミンを抽出剤として内包したマイクロカプセルを，SPG膜乳化法およびin-situ重合法により調製した．調製した小粒径TOA内包マイクロカプセルについて平均粒径，細孔分布，内包率等の物性値，塩酸溶液中からのパラジウムの抽出および逆抽出に及ぼすマイクロカプセル特性の影響を検討した．得られたマイクロカプセルの平均粒径はSPG膜細孔径の約半分のものが得られた．カプセル内部への抽出剤の内包率はほぼ100%の値を示し，in-situ重合法により高効率で抽出剤のマイクロカプセル化が可能であった．SPG膜乳化法を用いて調製したTOA内包マイクロカプセルによるパラジウムの抽出はいずれのマイクロカプセルを用いた場合も5分以内に抽出平衡に達した．抽出率も1に達し，マイクロカプセル平均粒径の減少に従い初期抽出速度が増加する結果が得られた．マイクロカプセル内部に抽出されたパラジウムは，チオ尿素塩酸溶液を逆抽出溶媒として用いることで，正抽出同様，迅速に逆抽出が行なわれ，10 min程度で完結した．また，正抽出，逆抽出を同一のマイクロカプセルで繰り返し行った結果，高い抽出率および逆抽出率を維持し，正抽出および逆抽出時における抽出剤の損失は無いものと考えられ，繰り返し利用に十分耐えうるマイクロカプセルの調製を可能にした．

Nylon-polystyrene microcapsules with immobilized ferroelectric liquid crystalline segments were prepared, and permeability control of an encapsulated core material was investigated under an external electric field. A ferroelectric liquid crystal monomer possessing both mesogenicity and chirality responded effectively to the external electrical field. Permeation of the material (oxprenolol) contained in the inner aqueous core of the microcapsules was enhanced under a weak electric field (2 V). Furthermore, the permeability of oxprenolol did not depend on the external electric field in the absence of the ferroelectric liquid crystal segments. To clarify the controlled-release mechanism of the core material, the light transmittance of the polymer membranes was quantitatively evaluated under an external electric field using a handmade polarized light transmittance apparatus.

The extraction of palladium(II) from an aqueous hydrochloric solution was carried out using divinylbenzene microcapsules containing tri-n-octylamine as the extractant. The preparation of these microcapsules was affected by the preparation conditions, such as the concentrations of the divinylbenzene, tri-n-octylamine and diluent. In the case of extremely low or high concentrations of divinylbenzene, and for the high concentration of tri-n-octylamine, the matrix-type microcapsules could not be prepared. The morphologies the prepared of microcapsules were spherical and the surface of the microcapsules was very smooth. The adsorption of palladium(II) onto the microcapsules was negligible compared to the extraction of palladium(II), and it found that the adsorption of palladium(II) onto the microcapsules did not occur. The extraction of palladium(II) into the microcapsules was affected by the characteristics of microcapsules such as, the surface area, pore diameter and volume, and the encapsulation efficiency of the tri-n-octylamine. The extraction of palladium(II) into the microcapsules seemed to have three steps. The first extraction step is caused by the tri-n-octylamine existing near the surface of the microcapsules. The second step is caused by the internal diffusion. The final step is the extraction equilibrium. Based on these results, the microcapsule that has a high encapsulation efficiency of tri-n-octylamine and small pore diameter seems to show the high extraction performance.

We report on the preparation of thermo-sensitive nano capsules using AOT reverse micellar method. Poly-N-isopropyl acryl amide that is thermo-sensitive material was prepared by AOT reverse micellar method, and we coat it by in-situ polymerization of divinylbenzene. Effect of preparation conditions on the nano capsule morphology, encapsulation efficiency of core meterial and release characteristics for temperature alteration were investigated. The morphology of nano capsules was globular shape and their diameter was affected by AOT concentration and divinylbenzene concentration. The encapsulation efficiency of core material was affected by the AOT concentration, the polymerization time of poly-n-isopropyl acryl amide and the DVB concentration. The encapsulation efficiency of core material was well correlated to the encapsulation efficiency of water. The release characteristic of core material from the thermo-sensitive nano capsules was significant over the phase transition temperature of poly-n-isopropyl acryl amide. These results confirm that the preparation method of thermo-sensitive nano capsules described in the present study is a novel and effective preparation method of nano capsules.

In order to construct a practical extraction recovery process of organic, phosphorous and hypophosphorous acids from wastewater of electroless nickel-plating with tri-n-octylamine in toluene, a closed circulation type continuous extraction equipments with the extraction and the back-extraction steps were developed. Two equipments, which were a laboratory scale having 30 ml reactor and a pilot plant scale having 450 ml reactor, were constructed with reactors having multiple vibration disks in a cylindrical tube for extraction and back-extraction, the settler for oil/water separation and the metering pump for transportation of the organic and the aqueous phase. The effect of pH and its control in the aqueous phase on these acids extraction were investigated using the laboratory scale equipment. The experiments using the pilot scale equipment, whose experimental condition was selected based on the acids extraction behavior in the laboratory scale equipment, was done to determine the practical conditions. In the treatment of a spent electroless plating bath using the pilot scale equipment, the treatable volume of the wastewater was 210 L/24 hr, and the recovered mass for hypophosphorous acid and phosphorous acid were 3.4 kg and 1.1 kg for 24 hr.

In order to construct a recovery process of nickel from the wastewater of electroless nickel-plating, the extraction of nickel in aqueous ammonium sulfate solution with 5-dodecylsalicylaldoxime in kerosene was carried out using a vibro-mixer type continuous extractor, which has multiple vibration disks in a cylindrical tube. The effects of the initial concentrations of extractant, nickel and proton, and the mean residence time of both solutions in the extractor on the extraction rate of nickel were measured. The experimental results correlated to the complete mixing flow of both fluids in the extractor were analyzed based on the interfacial reaction rate. The calculated results for each frequency of vibration plates were well explained by the experimental results. The average extraction rate in the vibro-mixer type extractor was interpreted based on a similar interfacial reaction equation derived in a Lewis-type transfer cell. The average extraction rate constants obtained in the vibro-mixer type extractor were 102- to 103-fold larger than that in the Lewis-type transfer cell. The mixing using the vibro-mixer type extractor generates and regenerates small droplets at high speed, causing enhancement of the interfacial area and the surface renewal rate.

In order to reduce the initial burst from polylactide (PLA) microspheres enclosing an antitumor agent, we prepared the microspheres with a smooth surface by varying solvent evaporation conditions such as operating temperature and pressure. PLA microspheres enclosing irinotecan hydrochloride (CPT) were prepared using the O/O emulsion system for solvent evaporation. The mean diameter and enclosing efficiency were almost constant because they were independent of solvent evaporation conditions. Scanning electron microscopic (SEM) observation verified the smooth surface of the PLA microspheres produced by varying the preparation conditions. In vitro release experiments show that the initial burst of microspheres with a smooth surface was less than that of those with a rough surface.

硝酸カリウムを含浸担持した活性炭を芯物質, ポリ-e-カプロラクトン (PCL) を壁物質として固体/有機相/外水相からなるS/O/Wエマルションの液中乾燥によりマイクロカプセルを調製した. 得られたマイクロカプセルの形状および硝酸カリウムの内包率におよぼすPCL濃度および活性炭重量分率の影響を検討した. PCL濃度が高くなるにしたがい, マイクロカプセル表面は滑らかになり, 内部の空隙が減少した. また, 硝酸カリウムの内包率は高くなった. 活性炭の重量分率の増加とともに硝酸カリウムの内包率は増加し, 2.5 wt%以上では一定となった. 硝酸カリウムを活性炭に担持させて内包させることにより, 内包率を比較的高く保ったまま内包量を高められた.