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1.
Within the frame of a continuing interest in occupational hygiene of hospitals as workplaces, we describe an automated analytical method by reversed-phase high-performance liquid chromatography for the measurement of contamination from the three most important nucleoside analogue antineoplastic drugs (5-fluorouracil, 5FU; cytarabin, CYA; gemcytabin, GCA) on such surfaces as those of preparation hoods and work-benches in departmental pharmacies of oncologic departments. Our method is characterized by a short analysis time (7 min) under isocratic conditions, by the use of a mobile phase devoid of organic solvent and by high sensitivity (LOD≥40 μg/l for all compounds), adequate to detect surface contamination above a threshold of 4 μg/m2 for wide surfaces and of 30 μg/m2 for small irregular objects. We present some results from a preliminary survey study recently performed in seven oncologic departments of two large general hospitals in Milan. To exemplify the contamination levels on various surfaces (such as on handles, floor surfaces and window glass panes, even far from the preparation hood), analyte concentrations in the order of 0.03–0.06 μg/ml, corresponding to 0.8–1.5 μg of 5FU were measured on telephones, of 0.02–0.6 μg/ml (0.85–28 μg/m2) of CYA were measured on table boards, of 0.05–10.6 μg/ml (1.2–1150 μg/m2) of GCA on furniture and floors. Spillage fractions up to 1% of the employed ANDs (employed daily 5FU 7–13 g; CYA 0.1–7.1 g; GCA 0.2–5 g) are measured on the polyethylene-backed paper disposable cover sheet of the preparation hood.  相似文献   

2.
Microbial environmental monitoring represents one of the most useful methods to assess potential risks related to the integrity of cultural heritage and people’s health. The monitoring plan described in the present work is based on standardized techniques for measuring microbial air and surface contamination. Air contamination is assessed through both active and passive samplings, measuring the concentration of microbes in air (in colony forming units per cubic metre, CFU/m3) and the rate at which microorganisms settle on surfaces (expressed by the Index of Microbial Air Contamination, IMA, CFU/dm2/h). For surface contamination, two parameters are measured using nitrocellulose membranes: the Microbial Buildup (MB, the total number of microorganisms accumulated on a surface in an unknown period of time prior to the sampling) and the Hourly Microbial Fallout (HMF, the number of microorganisms that settle on a specific surface during 1 h). The monitoring plan was implemented at the Pilotta Palace in Parma, Italy, during the Correggio exhibition in 2009. Samplings were taken before and during opening times. Some microbial contamination was already detected before the arrival of visitors: air contamination mean values of 99.1 CFU/m3 and 5.2 CFU/dm2/h were recorded, while MB and HMF mean values for surfaces were 92 and 7 CFU/dm2, respectively. A significant increase was recorded in air contamination during opening times, with mean values of 323.7 CFU/m3 and 19.4 CFU/dm2/h; surface contamination values increased as well. This monitoring plan represents a contribution towards the definition of a much needed standardized methodology.  相似文献   

3.
5-Fluorouracil (5-FU) is one of the most widely used antineoplastic drugs. It can be therefore considered to be a model compound for the identification of exposure routes during preparation and administration of cytostatic agents, especially for nucleoside analogue drugs. In this study, an HPLC–UV method was validated for determination of 5-FU in wipe samples by direct analysis of the aqueous solutions and in air samples by using solid-phase extraction (SPE). When samples were pre-treated on styrene–divinylbenzene resin SPE columns, a 20-fold preconcentration of the analyte was achieved. As regards air samples, correlation coefficients were always higher than 0.998 and the limit of detection was assessed at 15 ng on filter. In order to verify the reliability of these procedures, 5-chlorouracil was used as internal standard. The procedure presented here has been applied to the environmental monitoring of occupational exposed subjects. The amount of 5-FU ranged from 0.043 to 0.23 μg/m3 in air samples and from 0.2 to 470.1 μg/dm2 in wipe samples. 5-FU was also detected on the internal side of the gloves (0.07 to 3.77 μg/pair of gloves).  相似文献   

4.

Purpose

Life cycle assessment (LCA) has largely focused on characterizing the impact of outdoor emissions. However, the intake fraction (iF) of indoor air emissions could be more important. The present paper aims to determine the long-term intake fractions of indoor emissions, including multiple indoor removal pathways such as sorption on indoor surfaces, and to compare it to the outdoor intake fraction.

Method

The developed model accounts for the different removal pathways in buildings, including air exchange, degradation in the gas phase, degradation on surfaces, and finally partitioning between air, walls, and furniture assuming a kinetically limited material transfer between gas phase and a near-surface film. The indoor intake fraction is presented as a function of the adsorption and degradation rate on surfaces.

Results and discussion

The intake fraction of volatile substances is only affected by the ventilation rate, with a constant intake fraction of 1?×?10?2. For ozone-sensitive substances, indoor gas phase reactions can significantly reduce the intake fraction. Semi-volatile substances are affected by the adsorption and degradation on room surfaces. For highly adsorbing substances, the decrease in intake fraction is limited to a minimum value of 2.5?×?10?4 by the mass transfer rate between air and room surfaces for a typical office or residence room in developed countries with temperate climate. Indoor intake fraction is compared to outdoor intake fraction calculated using the Impact 2002 multimedia model. Typical calculated indoor intake fraction values are in a significantly higher range (2.5?×?10?4 to 1?×?10?2) than inhalation outdoor values (1?×?10?9 to 1?×?10?6).

Conclusions

This paper opens new possibilities to assess the health impact of indoor and outdoor air emissions in a consistent way, including surface sorption??a major removal pathway for semi-volatile compounds. By combining the newly calculated intake fractions with effect factors and with indoor and outdoor emissions per functional unit, it becomes possible to consistently account for indoor exposure in methods such as LCA  相似文献   

5.
Summary In submerged culture there was negligible growth of Fusarium moniliforme with either n-tetradecane or gasoil (C13–C19) as the only carbon and energy source. In surface culture the cell yield was about 0.25 g dm–3 dry weight after four weeks incubation. Some oxidation products, mainly isomeric tetradecanones (4-one, 5-one, 6-one and 7-one), could be identified. However the cell yield in a trickle-flow column was about 3 g dm–3 dry weight after 7 days. Only traces of oxidation products could be detected. In a fixed-bed reactor, filled with glass rings, cell yields were similar to those in the trickle-flow column and depended on the medium flow rate.After termination of growth in the fixed-bed reactor, similar amounts of gibberellic acid were produced in a nitrogen-free medium with either gasoil or glucose.  相似文献   

6.
The batch production of gluconic acid in the presence of glucose, sucrose and molasses was investigated using free mycelia of Aspergillus foetidus NRRL 337 in shake flasks. Eight growth parameters were chosen as independent variables. The temperature, pH, substrate type and initial concentrations, inoculum percentage and shake rate directly affected the specific microorganism growth and gluconic acid production rates. The optimum temperature and initial pH values were found to be 33°C and five to six, respectively. The maximum specific growth and gluconic acid production rates were established as 57 g/dm3 of glucose, 75 g/dm3 of sucrose and 150 g/dm3 of molasses. The optimum values of the shake rate, inoculum percentage and initial ammonium nitrate concentration were determined as 100 1/min, 0.5% and 1.5 g/dm3, respectively. The maximum gluconic acid concentrations corresponding to these initial substrate concentrations were observed to be 8.3 g/dm3, 17.4 g/dm3 37.0 g/dm3, respectively. The optimum specific microbial growth and gluconic acid production rates were found as 0.0145 1/h and 0.0375 g/g × h, respectively, for the fermentation conditions of SGo = 57 g/dm3, T = 28°C, initial pH = 6.5, N = 84 1/min, A = 0.5 g/dm3 and I = 0.5%.  相似文献   

7.
A high-performance liquid chromatography (HPLC) analytical method for the determination of oxolinic acid and flumequine in Artemia nauplii is described. The samples were extracted and cleaned up by a solid-phase extraction (SPE) procedure using SPE C18 cartridges. Oxolinic acid and flumequine were determined by reversed-phase HPLC using a mobile phase of methanol–0.1 M phosphate buffer, pH 3 (45:55, v/v) and a UV detection wavelength of 254 nm. Calibration curves were linear for oxolinic acid in the range of 0.2–50 μg/g (r2=0.9998) and for flumequine in the range of 0.3–50 μg/g (r2=0.9994). Mean recoveries amounted to 100.8% and 98.4% for oxolinic acid and flumequine, respectively. The quantification limit was 0.2 μg/g for oxolinic acid and 0.3 μg/g for flumequine. Quantitative data from an in vivo feeding study indicated excellent uptake of both drugs by Artemia nauplii.  相似文献   

8.
To further optimize a culture medium for induction of direct embryo formation of Oncidium cvs. Gower Ramsey and Sweet Sugar, five kinds of carbon sources, cellibiose, fructose, glucose, maltose and sucrose at 10, 20, 30 and 60 g dm−3 were tested in this study. Cellibiose supply had an inhibitory effect and resulted in high percentage of explant browning in both cultivars. By contrast, fructose, glucose and sucrose were all effective for direct embryo induction. In cv. Gower Ramsey, the suitable ranges of concentration were found at 30–60 g dm−3 of sucrose, 10–20 g dm−3 of glucose and 20–30 g dm−3 of fructose, respectively. The suitable ranges for cv. Sweet Sugar were at 20–60 g dm−3 of sucrose, 10–30 g dm−3 of glucose, 10–20 g dm−3 of fructose and 30–60 g dm−3 of maltose, respectively. The highest amount of embryos was obtained at 30 g dm−3 of sucrose for cv. Gower Ramsey and at 20 g dm−3 of glucose for cv. Sweet Sugar.  相似文献   

9.
Capillary electrophoresis (CE) poses unique challenges in many different analytical applications, mainly to biological and complex samples and when only small amounts of sample are available, due to its low sample consumption. As a consequence, poor limits of detection are usually observed with this technique, especially with UV photodetectors. Minimal or no sample treatment is desirable in any analytical method to avoid external sources of contamination or errors and to provide a high throughput. On- and in-capillary sample pre-concentration strategies, based on solid-phase extraction (SPE) technology can take advantage of both techniques (SPE and CE), while avoiding sample contamination and tedious manipulations when the sample amount is an issue. Moreover, the combination can provide two-dimensional separations. This review collects the most recent strategies that merge SPE technology built on- and in-capillary pre-concentration for increasing sensitivity and/or selectivity.  相似文献   

10.
Capillary electrophoresis (CE) poses unique challenges in many different analytical applications, mainly to biological and complex samples and when only small amounts of sample are available, due to its low sample consumption. As a consequence, poor limits of detection are usually observed with this technique, especially with UV photodetectors. Minimal or no sample treatment is desirable in any analytical method to avoid external sources of contamination or errors and to provide a high throughput. On- and in-capillary sample pre-concentration strategies, based on solid-phase extraction (SPE) technology can take advantage of both techniques (SPE and CE), while avoiding sample contamination and tedious manipulations when the sample amount is an issue. Moreover, the combination can provide two-dimensional separations. This review collects the most recent strategies that merge SPE technology built on- and in-capillary pre-concentration for increasing sensitivity and/or selectivity.  相似文献   

11.
Rapid method of in vitro multiplication of date palm was developed. Shoot tips were cultured on Murashige and Skoog (MS) medium supplemented with 2 mg dm–3 dimethylaminopurine (2iP) + 1 mg dm–3 naphthalene acetic acid (NAA). Shoot buds were proliferated from white nodular cultures on hormone free medium. Shoot bud proliferation strongly enhanced when cultured on MS-medium contained 3 mg dm–3 2iP + 0.5 mg dm–3 NAA. Culturing on full-strength MS medium showed higher multiplication rate compared with half-strength MS medium. Among four concentrations of sucrose used, 30 g dm–3 speeded up the bud proliferation more than 10, 20 and 40 g dm–3. However, the largest shoot buds were observed with 40 g dm–3 sucrose. Solidification of culture media by 1.75 g dm–3 Phytagel showed the highest proliferation rate, but the largest buds were observed with 1 g dm–3 Phytagel.  相似文献   

12.
The induction of secondary somatic embryogenesis in Abies numidica De Lann. was achieved. Precotyledonary, cotyledonary, and desiccated cotyledonary embryos were used as explants. Cotyledonary embryos before desiccation were the most suitable. The most beneficial was induction medium Schenk and Hildebrandt (SH) with 1 mg dm−3 thidiazuron and 1000 mg dm−3 myo-inositol. Initiation frequency was from 1 to 34 %. Maturation of somatic embryos was achieved on modified Murashige and Skoog medium supplemented with 40 g dm−3 maltose, 100 g dm−3 polyethylene glycol-4000 and 10 mg dm−3 abscisic acid. Mature somatic embryos after three weeks of desiccation germinated on SH medium with 10 g dm−3 charcoal and 10 g dm−3 sucrose. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

13.
Two selection systems for Agrobacterium tumefaciens mediated transformation of tomato and potato were compared. In the tomato (Lycopersicon esculentum cv. Moneymaker), the highest transformation rate, 4.2 %, of cotyledon explants on mannose-selection medium was obtained when mannose/sucrose concentration in the regeneration medium was 5/15 g dm−3. The best transformation efficacy with the commonly used concentration of 100 mg dm−3 kanamycin as a selection agent was 9 %. In the potato (Solanum tuberosum cv. Bintje), the highest transformation frequency was 53.3 % when mannose concentration in the regeneration medium was 5 g dm−3 during the first 3 weeks after transformation and 10 g dm−3 afterwards. The optimum concentration of sucrose was 20 g dm−3. The transformation efficiency using kanamycin as a selection agent at a concentration 100 mg dm−3 was 33.3 % with potato. Our results demonstrate that the transformation efficiency using mannose selection is 1.6-fold higher for potato and about 2 times lower for tomato comparing with the ordinary protocol using kanamycin.  相似文献   

14.
Methotrexate (MTX) is the prototype folate antagonist cytotoxic drug, employed in the therapy of solid tumors and leukaemias, and recently also as an immunosuppressive agent in organ transplantation, in the treatment of some autoimmune diseases and in the therapy of severe asthma. MTX is one of the very few antineoplastic drugs the therapeutic concentration monitoring of which is currently employed in clinical practice and can be routinely measured in biological samples by a number of different analytical techniques, among which are immunoenzymatic and chromatographic methods. Each technique has of course its own advantages in terms of sensitivity, specificity, speed, cost and level of expertise required. Along with therapeutic drug concentration monitoring and clinical pharmacology, fundamental research into the mechanism of action of antifolate drugs is still a field which requires the measurement of MTX, of its new analogues and of their metabolites in biological samples. This review summarizes the instrumental conditions and the performance of several published chromatographic methods employed to measure MTX, its metabolites and some analogues in clinical and biological research. More than 70 papers describing chromatographic assays for MTX and its metabolites have been published in the literature between 1975 and 2000. A wide array of experimental conditions for sample preparation, analyte separation and detection have been employed. According to their chemical properties, MTX, its metabolites and analogue drugs present in several biological samples (plasma, serum, saliva, urine, cerebrospinal fluid, tissue specimens) can be extracted, separated and detected under a variety of chromatographic conditions, i.e. on different stationary phases, under a wide choice of mobile phase conditions (acidic or neutral, employing ion-pair or micellar chromatography), followed by several detection techniques (UV–Vis spectrophotometry, pre- or post-column oxidation and fluorimetry, electrochemistry, mass spectrometry). Optimized methods allow simultaneous measurement within a few minutes of the plasma levels of MTX and its main metabolites at concentrations in the low-nM range. One special field which needs sensitive, fast and inexpensive methods for the detection and measurement of MTX is the monitoring of contamination in workplace environments, such as pharmaceutical industries and oncological hospital pharmacies, and in sewage waters. The measurement of the intracellular γ-oligo-glutamate metabolites of biological folates, of MTX and of some analogue drugs is of great importance in basic pharmacological research. The existence of empirical quantitative relationships between the retention of individual oligomers under different chromatographic conditions and the number of added glutamic acid units allows identification of the metabolites even when authentic standards are not available.  相似文献   

15.
This work presents the optimization of analytical procedures for the determination of two antibiotics, oxolinic acid (OA) and flumequine (FL), in bed sediment, river water, and soil samples. Three extraction methods (microwave-assisted extraction (MAE), ultrasonication, and reflux) were tested, and the highest recoveries were obtained with MAE (94 ± 3% and 95 ± 3% for OA and FL, respectively). A solid-phase extraction (SPE) clean-up step was optimized by comparing two polymeric sorbents: Oasis HLB and Oasis MAX. The final extracts were analyzed by liquid chromatography with fluorimetric detection. Limits of detection (LOD) obtained for OA and FL in soil and sediment ranged from 0.3 to 0.5 µg kg?1. Meanwhile, a novel SPE procedure was also implemented for OA and FL determination in river water samples. It also relied on the use of Oasis MAX, and recovery rates were in the range 90–94%; LODs were 2 ng L?1 for both OA and FL. These methods were applied for the analysis of samples taken in the Seine River basin (France). The obtained results demonstrated the widespread occurrence of OA and FL, at ng L?1 and µg kg?1 levels in water and sediment/soil, respectively, and their persistence in the environment.  相似文献   

16.
Wood furniture is an important source of indoor air pollution. To date, the detection of harmful substances in wood furniture has relied on the control of a single formaldehyde component, therefore the detection and evaluation of pollutants released by wood furniture are necessary. A novel method based on a cataluminescence (CTL) sensor system generated on the surface of nano‐3TiO2–2BiVO4 was proposed for the simultaneous detection of pollutants released by wood furniture. Formaldehyde and benzene were selected as a model to investigate the CTL‐sensing properties of the sensor system. Field emission scanning electronic microscopy (FESEM), transmission electron microscopy (TEM) and X‐ray diffraction (XRD) were employed to characterize the as‐prepared samples. The results showed that the as‐prepared test system exhibited outstanding CTL properties such as stable intensity, a high signal‐to‐noise ratio, and short response and recovery times. In addition, the limit of detection for formaldehyde and benzene was below the standard permitted concentrations. Moreover, the sensor system showed outstanding selectivity for formaldehyde and benzene compared with eight other common volatile organic compounds (VOCs). The performance of the sensor system will enable furniture VOC limit emissions standards to be promulgated as soon as possible. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

17.
To determine some physiological parameters implicated in somatic embryogenesis in date palm (Phoenix dactylifera L.), peroxidases have been studied. Activated charcoal commonly used in date palm tissue culture as an essential antibrowning factor decreased cellular protein contents and peroxidase activities. During the first months of culture, the conventionally used medium (100 mg dm?3 of 2,4-dichlorophenoxyacetic acid, 3 g dm?3 charcoal) reduces 2 to 3 and 4 to 6 times protein contents and peroxidase activities, respectively, in comparison with the same one containing only 5 mg dm?3 of 2,4-D and with or without 150 mg dm?3 charcoal. In addition, the standard procedure decreased the embryogenic potential which is positively related to the intra- and extracellular (excreted into culture medium) peroxidase activities. In medium with embryogenic calli, extracellular peroxidase activity was three times as high as the activity determined in the same medium with non-embryogenic calli. There were two basic isoforms and four to five acidic bands characterizing the embryogenic calli. It can be suggested that peroxidases play a key role in somatic embryogenesis of date palm and the charcoal used at 3 g dm?3 constitute a perturbating factor for this process.  相似文献   

18.
The present paper reports a protocol for minimum growth conservation of Drosophyllum lusitanicum (L.) Link. in vitro. Double-node cuttings were maintained for 4, 8 and 12 months at 5 or 25 °C in the dark. The effects of sucrose either alone at 5, 20, 30, 40 and 60 g dm−3 or at 20, 40 and 60 g dm−3 in combination with 20 g dm−3 mannitol, on survival and post-storage shoot multiplication efficiency were investigated. The cultures could effectively be conserved under minimum growth at 5 °C for 8 months on Murashige and Skoog’s medium supplemented with 60 g dm−3 sucrose, 20 g dm−3 mannitol and 0.91 μM zeatin. Following extended conservation, the cultures could be successfully regenerated into new shoots, and they were morphologically similar to those of non-stored controls.  相似文献   

19.
Zephyr lily (Zephyranthes grandiflora), an important ornamental plant has been micropropagated in vitro after controlling microbial contamination by a pretreatment with 0.2 % Bavistin and 0.1 % Pantomycin for 4 h before final sterilization with 0.1 % mercuric chloride. In 67 % of the sterile cultures, 11 shoots on average were regenerated directly from basal half of bulb scales in Murashige and Skoog (MS) medium containing 3 % sucrose and 2 mg dm−3 benzylaminopurine (BAP). Shoots emerged in bunches on a basal achlorophyllous bulbous part. Combination of 2 mg dm−3 BAP with 1 mg dm−3 gibberellic acid (GA3) enhanced shoot growth. Stout roots (maximum of 5–6 per shoot) were developed in presence of 1 mg dm−3 indole-3-butyric acid (IBA). Micro-bulbs showed potential of regeneration and could be used as secondary explants. The morphologically identical plants derived by in vitro propagation were genetically identical as shown by PCR based ISSR marker analysis of genomic DNA.  相似文献   

20.
An improved protocol for generation of viable cormlets from tissue culture derived shoots of saffron has been developed. Multiple shoots were generated from apical buds, small corms and in vitro developed single shoots. Bunches of two to three shoots when cultured on half strength Murashige and Skoog (MS) medium containing 3 mg dm−3 benzyladenine (BA) and 80 g dm−3 sucrose developed 1.89 cormlets per shoot bunch with an average fresh mass of 1.18 g. It took nine months from culture of apical buds to the harvest of cormlets but under field conditions 22 months. Sucrose appeared to be essential for cormlet induction as no cormlets were developed in the medium devoid of sucrose and only 0.29 per shoot in medium containing mannitol. In vitro derived cormlets sprouted from apical and axillary buds on MS medium containing 12 mg dm−3 BA, 3 mg dm−3 indolebutyric acid and 30 g dm−3 sucrose. Daughter cormlet formation from in vitro derived cormlets was also observed.  相似文献   

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