Uso de quitina e quitosana como adsorventes de amônia de efluentes aquícolas: revisão de literatura / Use of chitin and quitosan as adsorvents of ammonia of aquaculture effluents: a literature review / Uso de quitina y quitosana como adsorbentes de amonia de efluentes acuícolas: revisión de literatura

Os resíduos provenientes da aquicultura são derivados da ração e da excreção dos peixes e podem estar sedimentados, suspensos ou dissolvidos, ocasionando elevados valores de DBO, DQO, nitrogênio e fósforo. A produção de camarões no Brasil tem gerado elevadas quantidades de resíduos sólidos, tendo em vista que os exoesqueletos dos camarões correspondem a cerca de 40% do seu peso total, resultando num forte impacto ambiental. Diversas pesquisas envolvendo a quitina estão sendo desenvolvidas na área de tratamento de água, devido principalmente a sua capacidade de formar filme, sendo utilizada em sistemas filtrantes. Este polissacarídeo também pode ser utilizado como agente floculante no tratamento de efluentes, como adsorvente na clarificação de óleos, e principalmente na produção de quitosana. Atualmente a quitosana possui aplicações multidimensionais, desde áreas como a nutrição humana, biotecnologia, ciência dos materiais, indústria farmacêutica, agricultura, terapia genética e proteção ambiental. A quitosana é muito eficiente na remoção de poluentes em diferentes concentrações. Apresenta alta capacidade e grande velocidade de adsorção, boa eficiência e seletividade tanto em soluções que possuem altas ou baixas concentrações. O uso da biotecnologia, através do processo de adsorção utilizando adsorventes naturais e baratos, como a quitina e quitosana, minimiza os impactos ambientais da aquicultura tanto em relação aos provocados pelo lançamento de efluentes no meio ambiente quanto aos causados pelo descarte inadequado dos resíduos do processamento de camarões.(AU)

Aquaculture residues are derived from fish feed and excretion and may be sedimented, suspended or dissolved, resulting in high BOD, COD, nitrogen and phosphorus values. Shrimp production in Brazil has generated high amounts of solid waste, since shrimp exoskeletons account for about 40% of their total weight, resulting in a strong environmental impact. Several researches involving chitin are being developed in the area of water treatment, mainly due to its ability to form film, being used in filter systems. This polysaccharide can also be used as a flocculating agent in the treatment of effluents, as an adsorbent in the clarification of oils, and especially in the production of chitosan. Currently, chitosan has multidimensional applications, from areas such as human nutrition, biotechnology, materials science, pharmaceutical industry, agriculture, gene therapy and environmental protection. Chitosan is very efficient in the removal of pollutants at different concentrations. It presents high capacity and high adsorption velocity, good efficiency and selectivity both in solutions that have high or low concentrations. The use of biotechnology, through the adsorption process using natural and cheap adsorbents such as chitin and chitosan, minimizes the environmental impacts of aquaculture both in relation to those caused by the release of effluents into the environment and those caused by the inappropriate disposal of processing residues of shrimps.(AU)

Los residuos procedentes de la acuicultura se derivan de la ración y de la excreción de los peces y pueden estar sedimentados, suspendidos o disueltos, ocasionando elevados valores de DBO, DQO, nitrógeno y fósforo. La producción de camarones en Brasil ha generado grandes cantidades de residuos sólidos, teniendo en cuenta que los exoesqueletos de los camarones corresponden a cerca del 40% de su peso total, resultando en un fuerte impacto ambiental. Varias investigaciones involucrando la quitina se están desarrollando en el área de tratamiento de agua, debido principalmente a su capacidad de formar película, siendo utilizada en sistemas filtrantes. Este polisacárido también puede ser utilizado como agente floculante en el tratamiento de efluentes, como adsorbente en la clarificación de aceites, y principalmente en la producción de quitosana. Actualmente la quitosana posee aplicaciones multidimensionales, desde áreas como la nutrición humana, biotecnología, ciencia de los materiales, industria farmacéutica, agricultura, terapia genética y protección ambiental. La quitosana es muy eficiente en la eliminación de contaminantes en diferentes concentraciones. Presenta alta capacidad y gran velocidad de adsorción, buena eficiencia y selectividad tanto en soluciones que poseen altas o bajas concentraciones. El uso de la biotecnología, a través del proceso de adsorción utilizando adsorbentes naturales y baratos, como la quitina y quitosana, minimiza los impactos ambientales de la acuicultura tanto en relación a los provocados por el lanzamiento de efluentes en el medio ambiente en cuanto a los causados por el descarte inadecuado de los residuos del procesamiento de camarones.(AU)

Verificación del desempeño general del método Elecsys® Chagas en la detección de anticuerpos específicos contra Trypanosoma cruzi / Verification of the general performance of the Elecsys® Chagas method in the detection of specific antibodies against Trypanosoma cruzi

Resumen La enfermedad de Chagas es una parasitosis producida por Trypanosoma cruzi, prevalente principalmente en el continente americano, y observada en regiones no endémicas, producto de viajes y migraciones. El objetivo de este estudio fue comparar el desempeño del ensayo Elecsys® Chagas (Roche Diagnostics Alemania) (ECLIA) para el diagnóstico de la infección chagásica crónica con el método estándar y evaluar su posible empleo en reemplazo del método automatizado existente. Se estudiaron 77 muestras de sueros pertenecientes a pacientes con diagnóstico presuntivo de enfermedad de Chagas, procesadas por los distintos métodos disponibles en la Sección Parasitología del Hospital Muñiz: inmunoensayo quimioluminiscente de micropartículas (CMIA) (Abbott), enzimoinmunoanálisis de adsorción (ELISA) (Wiener) y hemaglutinación indirecta (HAI) (Lab. Lemos S.R.L.). Los resultados de los métodos ELISA y HAI fueron comparados con los obtenidos en la prueba ECLIA, y estos a su vez con el método automatizado disponible. De las muestras analizadas, 22 (28,57%) presentaron IgG anti-T. cruzi y 55 (71,43%) resultaron negativas. Con el método ECLIA se logró un 100% en los parámetros de desempeño, con diferencias en los intervalos de confianza. La razón de verosimilitud positiva y la razón de verosimilitud negativa clasificaron al ensayo como excelente y la potencia global del test apoyó esa afirmación. Los métodos inmunológicos automatizados ayudan a la performance diagnóstica en la etapa crónica de la enfermedad de Chagas, permiten minimizar errores, favorecen la velocidad de emisión de los resultados y, debido a su alta sensibilidad y especificidad, en ciertos escenarios podrían proponerse para usar como única técnica.

Abstract Chagas disease is a parasitosis caused by Trypanosoma cruzi, prevalent mainly in the American continent, and observed in non-endemic regions as a result of travel and migration. The objective of this study was to compare the performance of the Elecsys® Chagas (Roche Diagnostics Alemania) (ECLIA) assay for the diagnosis of chronic Chagas infection with the diagnostic standard, and to evaluate its possible use as a replacement for the existing automated method. A total of 77 serum samples belonging to patients with a presumptive diagnosis of Chagas disease were evaluated, processed by the different methods available in the Parasitology Section of Hospital Muñiz: microparticle chemiluminescent immunoassay (CMIA) (Abbott), enzyme-linked immunosorbent assay (ELISA) (Wiener) and indirect hemagglutination (HAI) (Lab. Lemos S.R.L). The results of the ELISA and HAI methods were compared with those obtained in the ECLIA test, and these in turn with the available automated method. Of the samples analysed, 22 (28.57%) presented IgG anti-T. cruzi and 55 (71.43%) were negative. With the ECLIA method, 100% was achieved in the performance parameters, with differences in the confidence intervals. The positive likelihood ratio and the negative likelihood ratio classify the essay as excellent, and the overall power of the test supports this statement. Automated immunological methods help diagnostic performance in the chronic stage of Chagas disease, allow minimising errors, favour the speed of issuance of results, and due to the high sensitivity and specificity, in certain scenarios, they could be proposed for use as single technique.

Resumo A doença de Chagas é uma parasitose causada pelo Trypanosoma cruzi, prevalente principalmente no continente americano, e observada em regiões não endêmicas em decorrência de viagens e migrações. O objetivo deste estudo foi comparar o desempenho do ensaio Elecsys® Chagas (Roche Diagnostics Alemanha) (ECLIA) para o diagnóstico da infecção crônica de Chagas com o método padrão e avaliar seu possível uso em substituição do método automatizado existente. Foram avaliadas 77 amostras de soro pertencentes a pacientes com diagnóstico presuntivo de doença de Chagas, processadas pelos diferentes métodos disponíveis na Seção de Parasitologia do Hospital Muñiz: imunoensaio quimioluminescente de micropartículas (CMIA) (Abbott), ensaio imunoenzimático de adsorção (ELISA) (Wiener) e hemaglutinação indireta (HAI) (Lab. Lemos S.R.L). Os resultados dos métodos ELISA e HAI foram comparados com os obtidos no teste ECLIA, e estes por sua vez com o método automatizado disponível. Das amostras analisadas, 22 (28,57%) apresentaram IgG anti-T. cruzi e 55 (71,43%) foram negativos. Com o método ECLIA, foram obtidos 100% nos parâmetros de desempenho, com diferenças nos intervalos de confiança. A razão de verossimilhança positiva e a razão de verossimilhança negativa classificam o ensaio como excelente, e a potencia geral do teste conformou essa afirmação. Os métodos imunológicos automatizados auxiliam no desempenho diagnóstico na fase crônica da doença de Chagas, permitem minimizar erros, favorecem a rapidez na emissão dos resultados e, devido à alta sensibilidade e especificidade, em determinados cenários, poderiam ser propostos para uso como técnica única.

Recent progress in magnetic nanoparticles and mesoporous materials for enzyme immobilization: an update / Progresso recente em nanopartículas magnéticas e materiais mesoporosos para imobilização de enzimas: uma atualização

Abstract Enzymes immobilized onto substrates with excellent selectivity and activity show a high stability and can withstand extreme experimental conditions, and their performance has been shown to be retained after repeated uses. Applications of immobilized enzymes in various fields benefit from their unique characteristics. Common methods, including adsorption, encapsulation, covalent attachment and crosslinking, and other emerging approaches (e.g., MOFs) of enzyme immobilization have been developed mostly in recent years. In accordance with these immobilization methods, the present review elaborates the application of magnetic separable nanoparticles and functionalized SBA-15 and MCM-41 mesoporous materials used in the immobilization of enzymes.

Resumo Enzimas imobilizadas em substratos com excelente seletividade e atividade apresentam alta estabilidade e podem suportar condições experimentais extremas, e seu desempenho foi mantido após repetidos usos. As aplicações de enzimas imobilizadas em vários campos se beneficiam de suas características únicas. Métodos comuns, incluindo adsorção, encapsulamento, ligação covalente e reticulação, e outras abordagens emergentes (por exemplo, MOFs) de imobilização de enzima, foram desenvolvidos principalmente nos últimos anos. De acordo com esses métodos de imobilização, a presente revisão elabora a aplicação de nanopartículas magnéticas separáveis ​​e materiais mesoporosos funcionalizados SBA-15 e MCM-41 usados ​​na imobilização de enzimas.

Effects of material interfaces on orientation and function of fibrinogen / 生物医学工程学杂志

Fibrinogen (Fg) in human plasma plays an important role in hemostasis, vascular repair and tissue integrity. The surface chemistry of extracellular matrix or biological materials affects the orientation and distribution of Fg, and changes the exposure of integrin binding sites, thereby affecting its adhesion function to platelets. Here, the quantity, morphology and side chain exposure of Fg adsorbed on hydrophilic, hydrophobic and avidin surfaces were measured by atomic force microscopy (AFM) and flow cytometry (FCM), then the rolling behavior of platelets on Fg was observed through a parallel plate flow chamber system. Our results show that the hydrophobic surface leads to a large amount of cross-linking and aggregation of Fg, while the hydrophilic surface reduces the adsorption and accumulation of Fg while causing the exposure and spreading of the α chain on Fg and further mediating the adhesion of platelets. Fg immobilized by avidin / biotin on hydrophilic surface can maintain the monomer state, avoid over exposure and stretching of α chain, and bind to the platelets activated by the A1 domain of von Willebrand factor instead of inactivated platelets. This study would be helpful for improving the blood compatibility of implant biomaterials and reasonable experimental design of coagulation

Application of iPDMS protein microarray in screening of tumor-associated antigen autoantibodies / 生物工程学报

The rapid screening of tumor markers is a challenging task for early diagnosis of cancer. This study aims to use highly sensitive chemiluminescent protein microarray technology to efficiently screen a variety of low abundance tumor related markers. A new material, termed integrated polydimethylsiloxane modified silica gel (iPDMS), was obtained by adding a surface polymerization initiator with olefin end to the conventional polydimethylsiloxane, and fixing into the three-dimensional structure of polydimethylsiloxane by thermal crosslinking through silicon hydrogen bonding. In order to make the iPDMS material resistant to non-specific protein adsorption, a poly(OEGMA) polymer brush was synthesized by surface-initiated atom transfer radical polymerization at the active initiation site. Finally, 20 tumor-related antigens were printed into the specific areas of the microarray by high-throughput spray printing technology, and assembled into 48-well detection microtiterplates of the iPDMS microarray. It was found the VEGFR and VEGF121 autoantibodies that obtained from 8 common tumors (breast cancer, lung cancer, colon cancer, gastric cancer, liver cancer, leukemia, lymphoma and ovarian cancer) can be used as potential tumor markers. The chemiluminescence labeled iPDMS protein microarray can be used for the screening of tumor autoantibodies at early stage.

Purification and component identification of total proanthocyanidins in Choerospondias axillaris pericarp / 中国中药杂志

The present study determined the quantitative markers of total proanthocyanidins in the purification of the industrial waste Choerospondias axillaris pericarp based on the comparison results of high-performance liquid chromatography(HPLC) and mass spectrometry(MS) and optimized the purification process with two stable procyanidins as markers. The adsorption and desorption of five different macroporous adsorption resins, the static adsorption kinetics curve of NKA-Ⅱ resin, the maximum sample load, and the gradient elution were investigated. The UPLC-Q-TOF-MS/MS was employed for qualitative analysis of the newly-prepared total proanthocyanidins of C. axillaris pericarp. As revealed by the results, NKA-Ⅱ resin displayed strong adsorption and desorption toward total proanthocyanidins. The sample solution(50 mg·mL~(-1)) was prepared from 70% ethanol crude extract of C. axillaris pericarp dissolved in water and 7-fold BV of the sample solution was loaded, followed by static adsorption for 12 h. After 8-fold BV of distilled water and 6-fold BV of 10% ethanol were employed to remove impurities, the solution was eluted with 8-fold BV of 50% ethanol, concentrated, and dried under reduced pressure, and purified total proanthocyanidin powder was therefore obtained. Measured by vanillin-hydrochloric acid method, the purity and transfer rate of total proanthocyanidins were 47.67% and 59.92%, respectively, indicating the feasibi-lity of the optimized process. UPLC-Q-TOF-MS/MS qualitative analysis identified 16 procyanidins in C. axillaris total proanthocyanidins. The optimized purification process is simple in operation and accurate in component identification, and it can be applied to the process investigation of a class of components that are difficult to be separated and purified. It can also provide technical support and research ideas for the comprehensive utilization of industrial waste.

Application of double plasma molecular adsorption system in children with acute liver failure / 中国当代儿科杂志

OBJECTIVE@#To study the efficacy and safety of double plasma molecular absorption system (DPMAS) in the treatment of pediatric acute liver failure (PALF).@*METHODS@#A prospective analysis was performed on the medical data of children with PALF who were hospitalized in the Intensive Care Unit (ICU), Hunan Children's Hospital, from March 2018 to June 2020. The children were randomly divided into two groups:plasma exchange group (PE group) and DPMAS group (@*RESULTS@#Compared with the PE group, the DPMAS group had a significantly lower number of times of artificial liver support therapy and a significantly shorter duration of ICU stay (@*CONCLUSIONS@#DPMAS is safe and effective in the treatment of PALF and can thus be used as an alternative to artificial liver support therapy.

Removal of Shield Needles from Graphene Oxide Thrombus and Preparation / 中国医疗器械杂志

Atherosclerosis is a chronic inflammatory disease commonly seen in clinical practice. It can lead to thickening of vascular intima, occlusion of lumen stenosis and thrombosis, leading to angina pectoris, hypertension, myocardial infarction and other diseases, posing a serious threat to human life and health. This study provides a method for removing shield needles from graphene oxide thrombus and its preparation. The graphene oxide shield needle mainly includes flexible rotating shaft, radial flexible rod, rotating needle, adsorption main pipe and dosing main pipe, laser measuring device, high definition camera and other structures, which has the following advantages:firstly, it achieves multi-angle rotation grinding thrombosis, precise rotation grinding, avoids vascular damage and infection; secondly, thrombolytic drugs can be applied in the process of rotary grinding and small thrombus can be adsorbed to effectively avoid secondary embolization of blood vessels; thirdly, it a coating of graphene oxide on a rotating needle, which protects against bacteria and infection. This study has practical reference value for the development of thrombotherapy and the application of graphene in the medical field.

Characterization of the biosorption of fast black azo dye K salt by the bacterium Rhodopseudomonas palustris 51ATA strain

BACKGROUND: Removal of dyes from wastewater by microorganisms through adsorption, degradation, or accumulation has been investigated. Biological methods used for dye treatment are generally always effective and environmentally friendly. In this study, biosorption of the Fast Black K salt azo dye by the bacterium Rhodopseudomonas palustris 51ATA was studied spectrophotometrically, at various pH (2­10), temperatures (25°C, 35°C, and 45°C) and dye concentrations (25­400 mg L-1). RESULTS: The bacterial strain showed extremely good dye-removing potential at various dye concentrations. IR studies at different temperatures showed that the dye was adsorbed on the bacterial surface at lower temperatures. Characteristics of the adsorption process were investigated by Scatchard analysis at 25°C and 35°C. Scatchard analysis of the equilibrium binding data for the dye on this bacterium gave rise to linear plots, indicating that the Langmuir model could be applied. The regression coefficients obtained for the dye from the Freundlich and Langmuir models were significant and divergence from the Scatchard plot was observed. CONCLUSION: The adsorption behavior of the dye on this bacterium was expressed by the Langmuir, Freundlich, and Temkin isotherms. The adsorption data with respect to various temperatures provided an excellent fit to the Freundlich isotherm. However, when the Langmuir and Temkin isotherm models were applied to these data, a good fit was only obtained for the dye at lower temperatures, thus indicating that the biosorption ability of R. palustris 51ATA is dependent on temperature, pH, and dye concentration.

Saccharomyces cerevisiae as a probiotic agent and a possible aflatoxin B1 adsorbent in simulated fish intestinal tract conditions / Saccharomyces cerevisiae como agente probiótico e possível adsorvente de aflatoxina B1 em condições simuladas do trato intestinal de peixes

The aim of this study was to evaluate in vitro the probiotic potential and absorption of Saccharomyces cerevisiae for the aflatoxin B1 in simulated fish intestinal tract conditions. Three yeast strains were used, two from brewery: S. cerevisiae RC1 and S. cerevisiae RC3 and one from a fish farming environment: S. cerevisiae A8L2. The selected yeasts were subjected to the following in vitro tests: homologous inhibition, self-aggregation, co-aggregation, antibacterial activity, gastrointestinal conditions tolerance and adsorption of AFB1. All S. cerevisiae strains showed good capability of self-aggregation and co-aggregation with pathogenic bacteria. All yeast strains were able to survive the gastrointestinal conditions. In acidic conditions, the factors (strain vs. time) had interaction (P=0.0317), resulting in significant variation among the strains tested in the time periods analyzed. It was observed that there was also interaction (P=0.0062) in intestinal conditions, with an increased number of cells in the 12-hour period for all strains tested. In the adsorption test, the A8L2 strain was statistically more effective (P<0.005) for both AFB1 concentrations evaluated in this study (10 and 25ng/mL). Thus, it was observed that the strains of S. cerevisiae have potential probiotic and adsorbent of AFB1.(AU)

Objetivou-se, com esta pesquisa, avaliar in vitro o potencial probiótico e adsorvente de Saccharomyces cerevisiae para aflatoxina B1 em condições simuladas do trato intestinal de peixes. Foram utilizadas três cepas de leveduras, sendo duas provenientes de cervejaria: S. cerevisiae RC1 e S. cerevisiae RC3, e uma de ambiente de piscicultura: S. cerevisiae A8L2. As leveduras selecionadas foram submetidas aos seguintes testes in vitro: inibição homóloga, autoagregação, coagregação, atividade antibacteriana, viabilidade às condições gastrointestinais e adsorção de AFB1. Todas as estirpes de S. cerevisiae mostraram boa capacidade de autoagregação e coagregação com bactérias patogênicas. Todas as estirpes de levedura foram capazes de sobreviver às condições gastrointestinais. Em condições ácidas, os fatores (cepa x tempo) tiveram interação (P=0,0317), resultando em variações significativas entre as cepas testadas nos períodos de tempo analisados. Observou-se que também houve interação (P=0,0062) em condições intestinais, havendo um aumento do número de células no período de 12h para todas as cepas avaliadas. No ensaio de adsorção, a estirpe A8L2 foi a mais eficaz estatisticamente (P<0,005), para as duas concentrações de AFB1 avaliadas neste estudo (10 e 25ng. mL-1). Dessa forma, conclui-se que as cepas de Saccharomyces cerevisiae possuem potencial probiótico e adsorvente de AFB1.(AU)

Kinetics and Equilibrium of Mercury Sorption by Three Different Types of Live Algae

Abstract The kinetics and equilibrium of experimental data of mercury (II) sorption using three different macrophytes E. crassipes, E. azurea and S. ariculata were analyzed. From the kinetic models used, the model 1, which considers the surface area of constant sorption, presents the coefficient of determination, R2, closer to the unit (0.97). Already, in the liquid phase, the best fit of the experimental data was obtained for model 2 (R2=0.96), which considers the variable surface area. The calculated values for the determination coefficients indicate that the Redlich-Peterson isotherm best describes the equilibrium (R2=0.79). The results show that the macrophyte S. ariculata surface area, which presented the highest adsorption potential (15.77x10-4m2.g-1), was far below those found in the best adsorbents. However, considering the large volume of adsorbent material required in an industrial plant and the low cost of the analyzed adsorbents, it is considered that the macrophytes investigated have a considerable potential for the removal of mercury from wastewater.

Caffeine Adsorption onto Bentonite Clay in Suspension and Immobilized

Abstract This study describes the use of bentonite in suspension for the caffeine adsorption (pollutant of emerging concern) by taking different conditions of the pH, adsorbent mass, adsorbent calcination temperature and interferents into account. The results were compared with those obtained using bentonite immobilized in alginate beads. The acid medium has a greater efficiency for the caffeine adsorption and the adsorbent calcination temperature exerts, due to structural changes. Caffeine removal higher than 90% was obtained at optimized conditions. The Langmuir model indicated a better fit of the data and the adsorption capacity of caffeine onto bentonite. The bentonite immobilized led to a slower adsorption process in relation to the suspended.

Degradation of Caffeine by Heterogeneous Photocatalysis Using ZnO with Fe and Ag

Abstract The organic compound caffeine when detected in environmental matrices such as surface waters and groundwater is considered as an emerging contaminant, in which its effects are still unknown. Therefore, in the present research, zinc oxide-based catalysts impregnated with iron and silver were prepared for the reaction of caffeine degradation by heterogeneous photocatalysis. The wet impregnation method with excess solvent was applied to the preparation of the materials, later they were characterized by adsorption of N2, X-ray diffraction and photoacoustic spectroscopy. Then, the photodegradation, photolysis and adsorption tests were carried out, in which it was observed that only the presence of the radiation or photocatalysts could not sufficiently degrade the caffeine, however when combined radiation with all the catalysts studied here presented degradation above 70% at the end of 300 minutes of the reaction, and the best catalyst studied was that containing 8% Ag in non-calcined ZnO. Thus, these results point out that the methodology employed in this research, both for the preparation of the catalysts and in the process of the photocatalysis reaction, was efficient in the degradation of the emerging contaminant, caffeine, which could later be used for a mixture of other contaminants.

Different Molarities and Dissolution-Precipitation Duration Affect the Formation of Carbonate-Apatite Blocks for Bone Graft Material

Abstract Objective: To determine diametral tensile strength and water absorption ability of Carbonate-apatite blocks fabricated from gypsum precursors (CaSO4) through a dissolution-precipitation method, with different solution molarities and immersion times. Material and Methods: Thirty-six CaSO4 gypsum specimens with 6 mm diameter; 3 mm height (Group A for diametral tensile strength) and 36 specimens of 6 mm diameter; 3 mm thickness (Group B for water absorption ability) were used. Each group was divided into 4 group treatments of: 1) dissolution-precipitation in solution of 0.5mol / L Na2CO3 + 0.5mol / L Na3PO4 for 48 hours and 72 hours; 1mol / L Na2CO3 + 1mol / L Na3PO4 for 48 hours and 72 hours. The C-Ap blocks were then tested using ATR-FTIR spectrometer to identify the formation of C-Ap functional groups. Furthermore, Group A specimens were tested for diametral tensile strength using Universal Testing Machine, and Group B specimens were tested for water adsorption ability using an analytical balance by measuring initial and final weight after immersion in saline solution at 37oC for 24 hours. Results: The formation of carbonate-apatite (C-Ap) in groups with solution molarity of 1 mol/L for 48 hours and 72 hours resulted in a lower diametral tensile strength and water absorption ability than the groups with a 0.5 mol/L solution. Conclusion: Solution with different molarities and dissolution-precipitation duration affect the formation of carbonate-apatite blocks.

Adsorption/desorption characteristics and enrichment of quercetin, luteolin and apigenin from Flos populi using macroporous resin

Abstract In this study, the adsorption/desorption characteristics of quercetin, luteolin and apigenin from Flos populi extract (Populus tomentosa Carrière, Salicaceae) on twelve macroporous resins (NKA-9, HPD-600, HPD-826, HPD-750, HPD-400, DM-130, AB-8, SP-825, X-5, D-101, HPD-100, HPD-200) were evaluated. Both high adsorption and desorption capacities of quercetin, luteolin and apigenin from Flos populi extract on SP-825 resin indicated that SP-825 resin was appropriate and its data were well fitted to the Langmuir and Freundlich isotherms. To get the optimal separation process, the influences of factors such as flow rates, loading sample volumes, concentrations of desorption solution were further investigated. Column packed with SP-825 resin was used to perform dynamic adsorption and desorption experiments. After one round of treatment, the contents of quercetin, luteolin and apigenin in the final products were 3.75-fold, 3.67-fold and 3.54-fold increased with recovery yields of 87.25, 85.19 and 82.22%, respectively. The results showed that the preparative enrichment of quercetin, luteolin and apigenin was available via adsorption and desorption on SP-825 resin. This method is a promising basis for the large-scale preparation of quercetin, luteolin and apigenin from Flos populi.

Use of Adsorbent Biochar from Pequi (Caryocar Brasiliense) Husks for the Removal of Commercial Formulation of Glyphosate from Aqueous Media

Abstract This study evaluated the capacity of adsorbent biochar derived from pequi husks to remove glyphosate (commercial formulation) in aqueous medium under three pH conditions (5.5, 7.0 and 8.0). This biochar presented a mean yield of 33.1% ± 2.66% and a high amount of surface particles of small dimensions endowing it with high surface area. The results showed that removal is proportional to pH increase in the range of 5.5 to 8.0. Adsorption assays performed at pH 7 and 8 fitted better to the Langmuir pseudo-first order kinetics model with fast adsorption in the first 15 to 30 minutes. The results for the acidic pH range fit none of the adopted models satisfactorily. The results obtained suggest that adsorbent can be used as an efficient and inexpensive alternative for the adsorption of glyphosate present in commercial formulations from aqueous matrices.

Application of affinity chromatography and its mathematical model in study of active components of traditional Chinese medicine / 中国中药杂志

Affinity chromatography is characterized by its high specificity,high recovery rate and sensitivity,and it has been widely used in the selection of active ingredients of traditional Chinese medicine,separation and enrichment of low molecular weight sugars and protein peptides,research on mechanism of action and discovery of targets.This paper reviewed the application of affinity chromatography and its adsorption isotherm model,kinetic model and adsorption thermodynamic mechanism in the field of traditional Chinese medicine.This summarizes and provides thinking for comprehensive applications of affinity chromatography theory in the field of active ingredient screening,purification and medicine interaction.

Bacterial degradation of anthraquinone dyes / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Anthraquinone dyes, which contain anthraquinone chromophore groups, are the second largest class of dyes after azo dyes and are used extensively in textile industries. The majority of these dyes are resistant to degradation because of their complex and stable structures; consequently, a large number of anthraquinone dyes find their way into the environment causing serious pollution. At present, the microbiological approach to treating printing and dyeing wastewater is considered to be an economical and feasible method, and reports regarding the bacterial degradation of anthraquinone dyes are increasing. This paper reviews the classification and structures of anthraquinone dyes, summarizes the types of degradative bacteria, and explores the possible mechanisms and influencing factors of bacterial anthraquinone dye degradation. Present research progress and existing problems are further discussed. Finally, future research directions and key points are presented.

Bioactive characteristics of an implant surface coated with a pH buffering agent: an in vitro study

PURPOSE: The purpose of this study was to evaluate the effectiveness of conventional sandblasted, large-grit, acid-etched (SLA) surface coated with a pH buffering solution based on surface wettability, blood protein adhesion, osteoblast affinity, and platelet adhesion and activation.METHODS: Titanium discs and implants with conventional SLA surface (SA), SLA surface in an aqueous calcium chloride solution (CA), and SLA surface with a pH buffering agent (SOI) were prepared. The wetting velocity was measured by the number of threads wetted by blood over an interval of time. Serum albumin adsorption was tested using the bicinchoninic acid assay and by measuring fluorescence intensity. Osteoblast activity assays (osteoblast adhesion, proliferation, differentiation, mineralization, and migration) were also performed, and platelet adhesion and activation assays were conducted.RESULTS: In both the wetting velocity test and the serum albumin adsorption assay, the SOI surface displayed a significantly higher wetting velocity than the SA surface (P=0.000 and P=0.000, respectively). In the osteoblast adhesion, proliferation, differentiation, and mineralization tests, the mean values for SOI were all higher than those for SA and CA. On the osteoblast migration, platelet adhesion, and activation tests, SOI also showed significantly higher values than SA (P=0.040, P=0.000, and P=0.000, respectively).CONCLUSIONS: SOI exhibited higher hydrophilicity and affinity for proteins, cells, and platelets than SA. Within the limits of this study, it may be concluded that coating an implant with a pH buffering agent can induce the attachment of platelets, proteins, and cells to the implant surface. Further studies should be conducted to directly compare SOI with other conventional surfaces with regard to its safety and effectiveness in clinical settings.