Evaluation of Total Hydrocarbon Contents in the Leaves of Selected Crops Grown on Crude Oil Polluted Agricultural Soil

Aim: The Total Hydrocarbon Content (THC) levels in the leaves of three edible plants (Allium cepa, Telfairia occidentalis and Zea mays) grown on soil polluted with 100 ml of crude oil were examined. Study Design: This experiment was conducted in two groups where the soil samples were polluted before planting (PB) and polluted 2 weeks after planting (PA). Place and Duration of Study: The research was carried out at the Federal University of Technology, Owerri (FUTO), Imo State, Nigeria, within a period of 4 weeks based on each group’s pollution time. Methodology: The tests for total hydrocarbon content (THC) were analyzed at different wavelengths for polluted soil and leaf samples using UV-Vis spectrophotometric method. Soil THC tests were determined on days 0, 14 and 28 respectively while THC tests on leaves of study plants were assessed on day 14 and 28. Results: The total hydrocarbon content values of the unpolluted soil (UPS) and the non-planted polluted soil (PS) subjected to this analysis on day zero were (UPS = 96.38 mg/kg; PS = 1082.80 mg/kg). However, results obtained on day 14 and 28 showed significant difference (P < 0.05) between the unpolluted soil sample (UPS) and all the planted polluted soil for Telfairia occidentalis (TOPB, TOPA), Allium cepa (ACPB, ACPA), Zea mays (ZMPB, ZMPA) as well as, the non-planted polluted soil (PS). For the leaf samples, TOPB had the highest THC value of 14.47mg/kg and 36.73 mg/kg for day 14 and 28 respectively while ZMPB had the lowest value of 5.38mg/kg at day 14 and ZMPA, the least THC value of 7.76mg/kg at day 28. Conclusion: Based on the varying THC levels observed in the leaves of crops used for this study; it was connoted that, bioaccumulation of hydrocarbons depends on the plants phytoremediation capability and the mode of pollution as observed in TOPB.

Heavy metal tolerance traits of filamentous fungi isolated from gold and gemstone mining sites

ABSTRACT Increased environmental pollution has necessitated the need for eco-friendly clean-up strategies. Filamentous fungal species from gold and gemstone mine site soils were isolated, identified and assessed for their tolerance to varied heavy metal concentrations of cadmium (Cd), copper (Cu), lead (Pb), arsenic (As) and iron (Fe). The identities of the fungal strains were determined based on the internal transcribed spacer 1 and 2 (ITS 1 and ITS 2) regions. Mycelia growth of the fungal strains were subjected to a range of (0-100 Cd), (0-1000 Cu), (0-400 Pb), (0-500 As) and (0-800 Fe) concentrations (mgkg-1) incorporated into malt extract agar (MEA) in triplicates. Fungal radial growths were recorded every three days over a 13-days' incubation period. Fungal strains were identified as Fomitopsis meliae, Trichoderma ghanense and Rhizopus microsporus. All test fungal exhibited tolerance to Cu, Pb, and Fe at all test concentrations (400-1000 mgkg-1), not differing significantly (p > 0.05) from the controls and with tolerance index >1. T. ghanense and R. microsporus demonstrated exceptional capacity for Cd and As concentrations, while showing no significant (p > 0.05) difference compared to the controls and with a tolerance index >1 at 25 mgkg-1 Cd and 125 mgkg-1 As. Remarkably, these fungal strains showed tolerance to metal concentrations exceeding globally permissible limits for contaminated soils. It is envisaged that this metal tolerance trait exhibited by these fungal strains may indicate their potentials as effective agents for bioremediative clean-up of heavy metal polluted environments.

Solid-phase extractions in flow analysis

ABSTRACT Coupling solid-phase extraction (SPE) to flow systems has promoted a synergistic development. Whereas SPE mechanization leads to improved precision and higher sample throughput, as well as diminishes systematic errors and contamination risks, analyte concentration and separation from the sample matrix provides a remarkable impact on detectability and selectivity in flow analysis. Historical aspects, main cornerstones, tips for system design, and recent applications are critically reviewed, in the context of analyte(s) separation/concentration, sample clean-up, and release of sorbed chemical species involving both packed (e.g. mini-columns, cartridges, and disks) or fluidized (e.g. beads and magnetic materials) particles. Novel (bio)sorbents, selective synthetic materials, and stationary phases for low-pressure chromatography are also discussed. Moreover, the feasibility of SPE for sample treatment before chromatographic separation, as well as the exploitation of direct measurements on the solid phase (optosensing) are emphasized.

Purification and Enrichment of Polycyclic Aromatic Hydrocarbons Pollutions in Oil-Field Water by Column Clean-up Coupled with Dispersive Liquid-Liquid Microextraction / 分析化学

A sample pretreatment method combining column clean-up with dispersive liquid-liquid microextraction (CCU-DLLME) for determination of polycyclic aromatic hydrocarbons (PAHs) in oil-field water was proposed. With this method,most organic interferences in matrix were cleaned up,and PAHs were purified, enriched and analyzed by gas chromatography/mass spectrometry directly. The influences on extraction efficiency including the kinds of column packing,weight ratio between column packing and sample, column flow rate,type and volume of extraction solvent, type and volume of disperser solvent and extraction time were investigated, respectively. Finally, 12 g of H103 macroporous resin was selected as column packing,12﹕5 of weight ratio between column packing and sample and 4 BV/h of column flow rate were selected in CCU. The resulting eluate was added with 1.00 mL of acetone (disperser solvent) and 15 μL of carbon tetrachloride (extraction solvent),followed by DLLME for 2 min. Under the optimum conditions,the enrichment factor of PAHs was 730-1579,the limits of detection (S/N=3) were 1.1-5.3 ng/L, the linear range was 0.01-50 μg/L,the RSDs(n=5) were 0.6%-3.4% and the recoveries were 82.6%-104.6%. This method could greatly reduce the influence of organic interferences in matrix, and was fit for the rapid analysis of pollutants in oil-field water especially.

Determination of Organophosphorus Pesticide Residues in Fruits and Vegetables Using Porous Carbon Nanoparticles Based on Citrus Compose / 分析化学

Porous carbon nanoparticles ( NPC) were prepared by ZnCl2 activation and carbonization using citrus waste as carbon source. A sample pretreatment method with NPC as dispersive solid phase extraction (d-SPE ) absorbent was established for the determination of organophosphorus pesticides in fruits and vegetables by gas chromatography. The NPC was characterized by scanning electron microscopy (SEM), X-ray diffraction ( XRD), FT-IR spectra, Raman spectroscopy, Brunauer, Emmett and Teller surface area(BET). Those results showed that the NPC was an amorphous porous carbon material with pore size in the range of 0-15 nm. Its specific surface area and pore volume were 1243 m2 / g and 1. 28 cm3 / g, respectively. The analysis conditions, including the amount and clean up time of adsorbent, were optimized by analysis of 14 kinds of oranophosphorus pesticides in fruits and vegetables with gas chromatography-flame photometric determination(GC-FPD). Moreover, the comparison for NPC with commercial materials of PSA, C18 and GCB was investigated in this study. The results indicated that the purification time was only 2 min using 0. 01 g NPC. The cost of NPC was about 25% of C18 , 21% of PSA and 16% of GCB. Because of the porous structure of NPC, the purification efficiency was significantly higher than the three commercial materials mentioned above. Under the optimum conditions, the calibration curves of the 14 organophosphorus pesticides were linear in the range of 0. 02-1. 00 mg / L with good correlation coefficients (R2>0. 99) and detection limits (S / N=3) of 0. 63-5. 30 μg / kg. The recoveries of the pesticides at three spiked levels ranged from 71. 3% to 114. 7%with the relative standard deviations (RSDs) of 0. 9% -12. 9% . The method is simple, rapid, sensitive, and low cost, and can satisfy the requirements of detection of organophosphorus pesticide residues in fruits and vegetables, displaying a good application prospect.

Clinical values of sodium hyaluronate combined arthroscopic joint clean-up surgery for the patellofemoral arthritis knee pain patients / 中国综合临床

Objective To investigate the clinical values of sodium hyaluronate combined arthroscopic joint clean-up surgery for the patellofemoral arthritis knee pain patients.Methods From June 2012 to September 2015 in Taihe Hospital Affiliated to Hubei Medical College,136 patellofemoral arthritis knee pain patients were selected and randomly divided into treatment group (68 cases) and control group (68 cases).All patients were given arthroscopic joint clean-up surgery,the control group were given the postoperative glucosamine sulfate capsules treatment,and the treatment group were given the postoperative intra-articular injection of sodium hyaluronate choose treatment,the treatment period was 5 weeks.Results Five weeks after treatment,the response rates in the treatment group and control group were 98.5％ (67/68) and 89.7％ (61/68),and the effect of the treatment group was better(x2 =4.202,P＜0.05).The pain scores in the treatment and control group were (1.34±0.45) points and (2.89±0.62) points,significandy lower than that of before operation ((7.30 ± 0.76) points and (7.31 ± 0.56) points;t =34.855,25.142;P ＜ 0.05).The Lysholm score in the treatment and control group were (88.87 ± 6.33) points and (76.13 ± 5.98) point,significantly higher than before operation ((44.23 ± 4.29) points and (44.67 ± 5.13) point;t =14.875,8.113;P＜0.05).The incidence of adverse events during the treatment in the treatment group and the control group were 8.8％(6/68) and 13.2％(9/68) respectively,there was no significant differemce between the two groups (x2 =0.391,P＞0.05).All adverse reactions after symptomatic treatment were improved.Conclusion Sodium hyaluronate combined arthroscopic joint clean-up surgery for the patellofemoral arthritis knee pain patients can effectively play the role of promoting the knee pain and function,and has good efficacy and safety,and is worth popularizing and applying.

Determination of Tetrodotoxin in Human Urine and Plasma after Immunoaffinity Column Clean-up Using Ultra-Performanc Hydrophilic Interaction Chromatography Coupled with Triple Quadrupole Mass Spectrometry / 分析化学

Anultra-performancehydrophilicinteractionliquidchromatography-triplequadrupolemass spectrometric ( UPLC-MS/MS) method was developed for the determination of tetrodotoxin ( TTX) in human urine and plasma. After the sample was cleaned-up and concentrated by immunoaffinity column, the separation of the TTX was carried out on an Acquity UPLC BEH amide column (100 mm×2. 1 mm, 1. 7 μm) with gradient elution using mobile phases of 0. 1% ( V/V) formic acid in water and acetonitrile. The analyte was detected by positive electrospray ionization mass spectrometry in the multiple reaction monitoring ( MRM) mode, and quantified by external solvent standard calibration. The measuring ranges of TTX in urine and plasma were 0. 05-400 μg/L. The average recoveries were 92%-95% and 91%-96% for TTX respectively spiked in urine and plasma with relative standard deviations of 3 . 3%-7 . 2% and 3 . 9%-7 . 8% ( n=5 ) . The limits of detection (LOD, S/N=3) and limits of quantitation (LOQ, S/N=10) of TTX were 0. 02 μg/L and 0. 05μg/L for urine and plasma, respectively. This method is suitable for the detection of TTX in urine and plasma for both forensic and clinical purposes.

Desarrollo y vaiidación de una metodología parala determinación de plaguicidass en café verde por cromatografía de gases / Method evelopmennt and validation for te determination of pesticides iin green coffee by gas chromatography

En este estudio se describe la implementación y validación de una metodología multirresiduo para la determinación de plaguicidas organoclorados, organofosforados y piretroides en café verde. Los plaguicidas se extrajeron con una mezcla de solventes acetona-agua (2:1) seguida de una partición con acetato de etilo- ciclohexano (1:1). Los extractos se limpiaron posteriormente por cromatografía de permeación en gel para eliminar principalmente grasa y cromatografía en minicolumna sobre silicagel para eliminar otros interferentes. La determinación analítica se realizó por cromatografia de gases de alta resolución con inyección splitless pulsada y detección simultánea por microcaptura electrónica (µ-ECD) y nitrógeno-fósforo (NPD) acoplados en paralelo. La metodología es específica, selectiva, precisa y exacta. Los porcentajes de recuperación de la mayoría de los compuestos estuvieron entre 70 y 110% al fortificar con mezcla de plaguicidas entre 0,038 y 1,536 mg/kg con límites de cuantificación entre 0,011 y 0,100 mg/kg.

This study describes the implementation and validation of a multiresidue methodology for the determination of organochlorine, organophosphorus and pyrethroids pesticides in green coffee. Pesticides residues were extracted from green samples with an acetone-water (2:1) mixture followed by ethyl acetate-cyclohexane (1:1) partitioning. The clean up steps include gel permeation chromatography and mini column chromatography using silicagel. Final determination was carried out by high resolution gas chromatography with a pulsed splitless injection mode and simultaneous detection by µ-ECD and NPD coupled in parallel. The methodology is specific, selective precise and accurate. Recoveries of majority of pesticides from spiked samples range from 70 to 110% at fortification levels of 0.038 mg/kg-1.536 mg/kg with limit of quantitation between 0.011 mg/kg and 0.100 mg/kg.

A comparison study of the effects of handpiece speed on teeth in debonding procedure / 대한치과교정학회지

This study was performed to examine treatment efficiency and patient discomfort rate according to used handpiece speed in clean-up technique. Brackets were bonded to extracted human premolar(50 teeth). After debonding, 50 extracted human premolar were divided into each two groups( low speed handpiece group with tungsten carbide bur and high speed handpiece group with ultra-fine diamond finishing bur ) of 25 according to used handpiece speed in clean-up technique. In clean-up procedure, teeth vibration and pulp thermal changes were measured. After clean-up procedure, the enamel surfaces of randomly selected 10 teeth from each two groups were taken by SEM and evaluated. The findings of this study were as follows ; 1. During resin removal, tooth vibrations of various amplitude in low speed handpiece group were more than those of high speed handpiece. 2. The pulpal thermal changes of high speed handpiece group were significantly higher than those of low speed handpiece group, also the resin removal time in high speed handpiece group was almost as twice as in low speed handpiece group. 3. The figures of SEM to enamel surfaces after resin removal showed that notches and resin remnants in high speed handpiece group were more than those in low speed handpiece group.