Beyond Single-Cell Analysis of Metallodrugs by ICP-MS: Targeting Cellular Substructures

Platinum compounds such as cisplatin (cisPt) embody the backbone of combination chemotherapy protocols against advanced lung cancer. However, their efficacy is primarily limited by inherent or acquired platinum resistance, the origin of which has not been fully elucidated yet, although of paramount interest. Using single cell inductively coupled plasma mass spectrometry (SC-ICP-MS), this study quantifies cisPt in single cancer cells and for the first time in isolated nuclei. A comparison of cisPt uptake was performed between a wild type (wt) cancer cell line and related resistant sublines. In both, resistant cells, wt cells, and their nuclei, cisPt uptake was measured at different incubation times. A lower amount of cisPt was found in resistant cell lines and their nuclei compared to wt cells. Moreover, the abundance of internalized cisPt decreased with increasing resistance. Interestingly, concentrations of cisPt found within the nuclei were higher than compared to cellular concentrations. Here, we show, that SC-ICP-MS allows precise and accurate quantification of metallodrugs in both single cells and cell organelles such as nuclei. These findings pave the way for future applications investigating the potency and efficacy of novel metallodrugs developed for cancer treatment.     

Characterization of aquatic groundwater colloids by a laser-induced breakdown detection and ICP-MS combined with an asymmetric flow field-flow fractionation

This study investigated the characteristics of natural groundwater colloids by a laser-induced breakdown detection (LIBD) and inductively-coupled plasma mass spectrometry (ICP-MS) in a combination with an asymmetrical flow field-flow fractionation (AsymFFFF). The groundwater was sampled from a borehole in the Yuseong area of Daejeon, Korea at different geological depths from 30 to 460 m and its geochemical parameters were measured. The combination of AsymFFFF and LIBD revealed a heterogeneous size fraction with a relatively broad size distribution of the groundwater colloids. One of the size fractions of the groundwater colloids was about 20 nm up to smaller than 100 nm, and the other fractions were larger than 100 nm. The elemental composition of the groundwater colloids was also analyzed by the AsymFFFF coupled with an ICP-MS. Results from the ICP-MS coupled with the AsymFFFF provided us with information about the size-specific elemental composition. The smaller sized fractions mainly consisted of calcite colloids with strontium, whereas the larger fractions were comprised of colloids such as aluminosilicates and iron oxides. The observations of all the groundwater samples indicate a similar pattern for the colloid fractions in size and in element composition except in the concentration.     

Digital In-Line Holography as a Three-Dimensional Tool to Study Motile Marine Organisms During Their Exploration of Surfaces

The swimming patterns of zoospores of the green alga Ulva linza in the vicinity of a surface were investigated by digital in-line holography. Full 3D motion patterns were retrieved from measurements and the traces obtained were compared with known swimming patterns of spores of the brown alga Hincksia irregularis and the green alga Ulva linza as seen in a conventional optical microscope. Quantitative information such as swimming velocity was calculated from the 3D traces. The results demonstrate the potential of digital in-line holography to image and quantify exploratory patterns of behavior of motile spores close to surfaces. This technique can give detailed insight into mechanisms of surface colonization by spores and larvae of fouling organisms in response to changes in surface properties.     

Characterization of Commercial Grades of Poly(Carbonate of Bisphenol A)

This study characterized three different commercial grades of poly(carbonate of bisphenol A) samples (for extrusion, CD, and DVD) by several instrumental analysis methods, such as elemental analysis (EA), inductively coupled plasma mass spectrometry (ICP-MS), Fourier-Transform infrared spectroscopy (FTIR), viscosity measurements, differential scanning calorimetry (DSC), and thermogravimetry analysis (TGA). The results of EA and ICP-MS showed that the chemical composition of the samples has no significant differences and the C/H ratio approaches theoretical value. The most abundant metal element in the samples is Fe. FTIR spectra demonstrated they have the same chain structure. Comparing the intrinsic viscosities and viscosity average molecular weights from the results of viscometry analysis, the values fell in the order: extrusion grade > CD grade > DVD grade. Various thermal properties determined by DSC and TG analysis showed the same sequence as the results of viscometry analysis and a close relationship between molecular weight and thermal properties was found.     

Microwave induced reactive base wash for the removal of oxidation debris from carboxylated carbon nanotubes

Removal of oxidation debris for generating high purity functionalized carbon nanotubes (CNTs) has been a challenge, where base washing has been found to be an effective purification treatment. In this paper we report microwave induced reactive base wash (MRW) as a fast, green alternate to conventional filtrate washing. Carboxylated CNTs of three different dimensions were subjected to MRW and the results were compared to conventional base-wash. The results showed that MRW was an effective method for the removal of oxidation debris which reduced the reaction time from 4 h to 20 min and alkali consumption by 75%. The CNTs from MRW were similar to those from conventional base wash in terms of dimensions, elemental composition, BET surface area and colloidal stability in aqueous media.     

Dependence of Graphene Oxide (GO) Toxicity on Oxidation Level,Elemental Composition,and Size

The mass production of graphene oxide (GO) unavoidably elevates the chance of human exposure, as well as the possibility of release into the environment with high stability, raising public concern as to its potential toxicological risks and the implications for humans and ecosystems. Therefore, a thorough assessment of GO toxicity, including its potential reliance on key physicochemical factors, which is lacking in the literature, is of high significance and importance. In this study, GO toxicity, and its dependence on oxidation level, elemental composition, and size, were comprehensively assessed. A newly established quantitative toxicogenomic-based toxicity testing approach, combined with conventional phenotypic bioassays, were employed. The toxicogenomic assay utilized a GFP-fused yeast reporter library covering key cellular toxicity pathways. The results reveal that, indeed, the elemental composition and size do exert impacts on GO toxicity, while the oxidation level exhibits no significant effects. The UV-treated GO, with significantly higher carbon-carbon groups and carboxyl groups, showed a higher toxicity level, especially in the protein and chemical stress categories. With the decrease in size, the toxicity level of the sonicated GOs tended to increase. It is proposed that the covering and subsequent internalization of GO sheets might be the main mode of action in yeast cells.     

原子荧光法测定二丁基二月桂酸锡中锡含量

经氧化、分解及消化后,二丁基二月桂酸锡转化成无机锡,分别采用常规化学滴定法、电感耦合等离子质谱法(ICP-MS)及原子荧光光谱法(AFS)测定二丁基二月桂酸锡中的锡含量,结果表明这3种测试手段所测数值基本一致。较其他两种方法而言,原子荧光光谱法具有简便、快速、准确、灵敏度高等特点。针对原子荧光光谱法的加标回收实验结果为99.2%～100.8%,表明该法测定的结果准确可靠,适合作为测定二丁基二月桂酸锡中锡含量的常规检测方法。     

Combustion synthesis and luminescence properties of Eu-doped Ca–α-SiAlON

Investigated were the combustion synthesis of Eu-doped Ca–α-SiAlONs and their luminescence properties. Experimentally established were (a) green compositions ensuring maximal extent of conversion, (b) influence of elemental composition on phase composition and microstructure of synthesized Ca–α-SiAlONs, and (c) influence of elemental composition on the excitation and emission spectra of Ca–α-SiAlON luminophors.     

丙烯腈与衣康酸在1-丁基-3-甲基咪唑氯化物中的共聚反应

以离子液体1-丁基-3-甲基咪唑氯化物为溶剂,研究了丙烯腈（AN）与衣康酸（IA）的二元共聚反应。利用红外光谱和元素分析法对聚合物进行了化学结构和组成分析,结果表明在离子液体中制备的AN与IA的共聚物与在常规溶剂中的产物有相同的结构并且组成相近。对共聚反应动力学进行了详细探讨,确定了AN与IA在离子液体中较适宜的反应条...     

Fatty acid metabolism in the chloroplast lipids of green and blue-green algae

The pattern of uptake of radioactivity into chloroplast lipids when a green alga (Chlorella vulgaris) was incubated with sodium 2-¹⁴C-acetate differed appreciably from that obtained when two blue-green algae (Anabaena cylindrica andAnacystis nidulans) were incubated under similar conditions. The fatty acids of the digalactosyl diglyceride and sulphoquinovosyl diglyceride fractions from the blue-green algae were labeled more rapidly than were those of the corresponding fractions fromC. vulgaris, whereas the activity in the acids of the phosphatidyl glycerol fraction fromA. cylindrica andA. nidulans was relatively lower than that in the green alga. The results indicate that the metabolic behavior of chloroplast lipids may vary considerably according to the class of alga concerned. In all three alga, the evidence points to an intermediary function for the chloroplast lipids in fatty acid synthesis. Only limited exchange of acyl groups between the different chloroplast lipids seemed to occur during photoautotrophic growth.     

Automated bone marrow analysis using the CD4000 automated haematology analyser

At present, bone marrow analysis is performed microscopically, but is time consuming and labour intensive. No automated methods have been successfully applied to classification of bone marrows cells because automated blood cell analysers have been incapable of identifying erythroblasts. The present study was designed to evaluate automated analysis of bone marrow aspirates with the CELL-DYN 4000 (CD4000) haematology analyser, which enables automated determination of erythroblast counts in both the normal mode (haemolytic time; 11.5s) and the resistant RBC mode (34.0s). The percentages of subpopulations including lymphocytes, neutrophils and erythroblasts were obtained with the CD4000, and as a reference, differential counts by microscopic observation of May-Grünwald-Giesa-stained films of bone marrow aspirates were performed (n=98). Significant correlations (P < 0.01) between the results obtained with the two methods were observed for total nucleated cell count and lymphocytes, neutrophils, erythroblasts and myeloid/erythroid (M/E) ratio. However, there were biases in the average percentages of erythroblasts, lymphocytes and M/E ratio obtained using the normal mode with the CD4000 toward values lower than those obtained with the microscopic method. Using the RBC resistant mode with the CD4000, the average percentages of erythroblasts, lymphocytes and M/E ratio approximated those obtained with the microscopic method. In conclusion, the CD4000 in resistant RBC mode is more useful for analysis of bone marrow aspirates than is the normal mode, because the former better approximates the M/E ratio than the latter.     

The importance of an extensive elemental analysis of single-walled carbon nanotube soot

Few manufacturers provide elemental analysis information on the certificates of analysis of their single-walled carbon nanotube (SWCNT) soot products, and those who do primarily perform surface sensitive analyses that may not accurately represent the bulk properties of heterogeneous soot samples. Since the accurate elemental analysis of SWCNT soot is a requisite for exacting assessments of product quality and environmental health and safety (EH&S) risk, the purpose of this work was to develop a routine laboratory procedure for an extensive elemental analysis of SWCNT soot using bulk methods of analyses. Herein, a combination of carbon, hydrogen, nitrogen, sulfur, and oxygen (CHNS/O) combustion analyses, oxygen flask combustion/anion chromatography (OFC/AC), graphite furnace-atomic absorption spectroscopy (GF-AAS), and inductively coupled plasma-mass spectroscopy (ICP-MS) were used to generate a 77-element analysis of two as-received CoMoCAT® SWCNT soot products. Fourteen elements were detected in one product, nineteen in the other, and each data set was compared to its respective certificate of analysis. The addition of the OFC/AC results improved the accuracy of elements detected by GF-AAS and ICP-MS, and an assessment was performed on the results that concluded that the trace elemental impurities should not pose an EH&S concern if these soot products became airborne.     

Hydrothermal fractional pretreatment of sea algae and its enhanced enzymatic hydrolysis

BACKGROUND: Sea algae cellulose has been little utilized because the cellulose content in sea algae is low. For the effective utilization of sea algae cellulose, cellulose must be converted without drying into valuable material with a high rate and yield. From this viewpoint, effects of hydrothermal pretreatments of sea algae to enhance the glucose production by enzymatic hydrolysis of sea algae cellulose were investigated. RESULTS: Using hydrothermal pretreatment performed at 423 K for Monostroma nitidum Wittrock (green alga) and at 473 K for Solieria pacifica (red alga) for 30 min, yields of extracted water‐soluble components containing monosaccharides were 0.51 g g^?1 for the green alga and 0.62 g g^?1 for the red alga. The apparent rate of glucose production from hydrothermally pretreated green alga by enzymatic hydrolysis was > 10 times faster than that of the non‐pretreated sample. Yields of glucose from cellulose by enzymatic hydrolysis were 79.9% for the green alga and 87.8% for the red alga. CONCLUSION: Cellulose of sea algae was successfully fractionated by hydrothermal pretreatments, which resulted in high susceptibility of sea algae cellulose to enzyme attack. This process leads to the effective utilization of sea algae cellulose. Copyright © 2008 Society of Chemical Industry     

Oxidative Stability and In Vitro Release Properties of Encapsulated Wheat Germ Oil in Saccharomyces cerevisiae Cell-Based Microcapsules

This research aims to evaluate the feasibility of Saccharomyces cerevisiae cell-based microencapsulation for wheat germ oil (WGO) based on oxidative stability and in vitro release properties. Microencapsulation of samples is achieved by freeze-drying WGO-in water emulsions containing alive, non-plasmolyzed, and plasmolyzed yeast cells. The encapsulation efficiency (EE), loading capacity (LC), release characteristics, and oxidative stability of WGO are determined before and after microencapsulation. The amount of β-carotene in the digesta is used to evaluate the release properties. Plasmolyzed yeast cells yield the highest EE (43.1%) and LC (216.5 g kg⁻¹). In cases where alive and non-plasmolyzed yeast cells were used as an encapsulant, a higher release rate was obtained in esophagus-stomach conditions, while higher digestion took place mainly in the duodenum and ileum with plasmolyzed cells. Encapsulation of WGO in plasmolyzed yeast cells provide the lowest peroxide and p-anisidine values and the highest oxidative protection during the accelerated oxidation test at 60 °C for 24 days. This result is also confirmed by Rancimat induction time. Practical Applications: Removing the plasma content by plasmolysis changes the structure of the yeast cell membrane and improves the encapsulation ability and release properties. Encapsulation of WGO with plasmolyzed yeast cells provides superiority in oxidative stability compared to native WGO. The potential value of WGO as an ingredient in the preparation of functional foods could be achieved by yeast cell encapsulation.     

Ionic liquid catalyzed synthesis of organosoluble wholly aromatic optically active polyamides

A series of optically active wholly aromatic polyamides (PAs) with amino acid moieties in the pendant groups have been synthesized through polycondensation of a chiral diacid and aromatic diamines in an ionic liquid (IL) as a green, safe and eco-friendly medium and also reactions catalysis agent (method I). Furthermore, the polymerization reactions were performed via conventional polycondensation (method II) and obtained results have been compared. Evaluation of data shows that IL is the better polyamidation medium and catalysis stand on the higher inherent viscosities and yields of the obtained PAs and the rate of polymerizations beyond the greener reaction conditions and deletion of some essential reagents in conventional manners. Characterization were performs by means of ¹H-NMR and FT-IR spectroscopy, elemental analysis, thermogravimetric analysis and differential scanning calorimetric techniques.     

DMA as a Gas Converter from Aerosol to "Argonsol" for Real-Time Chemical Analysis Using ICP-MS

In this study, "Argonsol" is defined as an assembly of liquid or solid particles suspended in argon, just as an aerosol is a suspension in air. Argonsol can be generated by a nebulizer and fed into a plasma torch for measurement by inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS). We have developed a new gas-conversion method, by means of a DMA, from normal aerosol to size-classified Argonsol for a chemical analysis using ICP-MS. A test aerosol containing lead as a typical toxic heavy metal was introduced into this system. With this system the size-related elemental concentration of lead nitrate particles in the range of 30 to 140 nm was measured. The sensitivity of this system is better than fg (10 -15 g) of lead in the total mass of particles introduced into ICP-MS. In principle, it is possible for our system to analyze all the elements that ICP-MS and/or ICP-AES can analyze.     

蜂窝陶瓷固定化酵母细胞啤酒连续主发酵工艺

对蜂窝陶瓷固定化酵母细胞啤酒连续主发酵工艺进行了实验研究，提出了优化的工艺条件：发酵温度17~18℃，稀释率0.045 h-1. 在此工艺条件下，实际测得浓度的降低量为6.91%，嫩啤酒双乙酰含量为0.180 mg/L. 嫩啤酒主要理化指标的测定结果表明，采用固定化酵母细胞啤酒主发酵工艺不会对啤酒质量造成影响.     

The size of polyaromatic layer of coal char estimated from elemental analysis data

The structure of coal char was investigated based on elemental composition of char. Char used in this study were prepared at 800 °C from four demineralized Argonne Premium Coals. Elemental analysis was made using the conventional ultimate analysis method, and hydrogen content was determined by the temperature programmed oxidation method. This method is more reliable for hydrogen analysis than the conventional method. The H/C atomic ratio was evaluated at 0.16–0.18 for these chars. It is impossible to determine the char structure only with elemental analysis data. However, it becomes possible to deduce the layer size, if making some assumptions about the peripheral structure of polyaromatic layer of coal char. If the presence of four bridges per each cluster is assumed, then the polyaromatic layer size of these chars was calculated to be from 1.7 to 2.2 nm. These values were compared with those obtained using other methods like X-ray diffraction, nuclear magnetic resonance technique, and others.     

Experimentation of a new mode of batch culture for lactic acid bacteria: cell reuse with an initial period of cell reactivation at acidic pH

Cell reuse was compared with conventional batch culture for lactic acid fermentation, the objective was to simplify the batch process and to alleviate the need for added nitrogen. At high levels of nitrogen supplementation to the culture medium (20 g dm^?3 yeast extract and 5 g dm^?3 each of tryptic and pancreatic casein peptones), similar mean production rates were obtained with partial cell reuse and the conventional batch process, without any additional gain when cells were initially reactivated at acidic pH. On the other hand, cell reuse with an initial period without pH control appeared particularly effective for low levels of nitrogen supplementation (5 g dm^?3 yeast extract): a 57% increase in the mean production rate with regard to the conventional batch process was obtained. © 2001 Society of Chemical Industry     

The very long chain fatty acids of the green alga,Chlorella kessleri

Fatty acids of the fresh-water green alga,Chlorella kessleri (heterotrophically cultivated), were fractionated (as methyl esters) using high performance liquid chromatography (HPLC). A fraction of fatty acids with chain lengths longer than 28 carbon atoms was analyzed by gas chromatography-mass spectrometry (GC-MS). The very long chain fatty acids, ranging from 31 to 36 carbon atoms, were found for the first time in a green alga.