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1.
A supramolecular catalytic kinetic spectrofluorimetric method was developed for the determination of platinum(IV) and the
possible mechanism of catalytic reaction was discussed. The method was based on the fluorescence-enhancing reaction of salicylaldehyde
furfuralhydrazone (SAFH) with potassium bromate, which was catalysed by platinum(IV) in a water–ethanol medium. β–Cyclodextrin (β-CD) obviously sensitized the determination at pH 5.20 and 25°C. Under optimum conditions, the β-CD–platinum–KBrO3–SAFH supramolecular kinetic catalytic reaction system had excitation and emission maxima at 372 and 461 nm, respectively.
The linear range of this method was 0.60–180 ng ml−1 with a relative standard deviation of 1.2%, and the detection limit was 0.18 ng ml−1. Investigation of the mechanism and the effects of interferences is presented. The proposed method was applied successfully
to determine trace platinum(IV) in the chemotherapeutic drug cisplatin and serum from patients with satisfactory results.
相似文献
2.
Summary A capillary gas chromatographic method is described for the determination of cisplatin based on the complexation of platinum(II)
with bis(isovalerylacetone) ethylenediimine (H2IVA2en) and extraction in chloroform. The chromatography was carried out on a BP1 or a BP5 column with an FID. Copper(II), nickel
(II) and palladium(II) separated completely and did not affect the determination of platinum(II). The method was applied of
the determination of cisplatin in a pharmaceutical preparation and blood samples of cancer patients after infusion of cisplatin.
The amounts of cisplatin in blood were found to be within 246–283 ng mL−1 with a C.V. of 2.35–4.26%. 相似文献
3.
G. M. Brahmanandhan S. Selvasekarapandian J. Malathi D. Khanna M. P. Rajan A. G. Hegde 《Journal of Radioanalytical and Nuclear Chemistry》2007,274(2):361-366
The terrestrial gamma-radiation in soil and sand samples collected around Kudankulam nuclear power plant site, i.e., in Radhapuram
Taluk of Tirunelveli District has been measured using NaI(T1) gamma-ray spectrometer. In the soil samples total dose due to
three primordial radionuclides lies in the range of 13.1–168.2 nGy/h with a geometric mean of 137.2 nGy/h, which yields an
annual effective dose of 0.17 mSv/y. In the sand samples the total dose due to three primordial radionuclides has been found
to be in the range of 38.1–1964.4 nGy/h with a geometric mean of 300.8 nGy/h, which gives an annual effective dose of 0.37
mSv/y which is well below the permissible limit (1 mSv). 相似文献
4.
D. Palacios D. Castro M. Perez F. Urbani L. Sajo-Bohus J. J. LaBrecque 《Journal of Radioanalytical and Nuclear Chemistry》1999,241(1):69-73
The concentrations of40K,226Ra,232Th and137Cs were determined in the upper layers of soils in the central coastal region of Venezuela. The activities of137Cs are higher in the areas where the forest is well developed, oriented towards the wind and at higher elevations. The origin
of the137Cs deposition is from water input from the clouds directly in the cloudforest and rainfall from the northeast trade winds.
Even though the values of137Cs are much higher in these areas, there is little or no significant increase in the health risk. The natural radioactivity
is correlated with the geology in the region except in the area of Urama. The values for the natural radiation background
are as follows: for potassium between 1–3%, for radium between 1–3 ppm and for thorium the range was 6–39 ppm. The corresponding
amounts of absorbed dose rates in air, the exposure rates and the annual effective dose equivalents are in the following ranges
respectively: 11–39 pGy/s, 4–16 uR/h and 0.25–0.86 mSv/y. The annual effective dose equivalents include the contribution of
the global average (2.57 mSv/y) of the rest of the natural sources of radiation. Finally, the largest natural radioactivity
background, was found near Chichiriviche as a result of the massive granite deposits in this area, but again there is no significant
health risk. 相似文献
5.
Günseli Yaprak Mahmoud A. A. Aslani 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(2):279-287
The surveys of natural gamma-emitting radionuclides in soils from three basins of West Anatolia intensively used for agricultural
purposes were conducted during 1998–2003. In the present study, part of the survey, the activity concentrations of 238U, 232Th and 40K in the soil samples from 43 sites distributed all over the agricultural land known as Büyük Menderes basin were determined
by scintillation gamma spectrometry. The average activity concentrations and ranges of the relevant radionuclides in the soils
were as follows: 238U was 29 (7–84); 232Th, 22 (10–48) and 40K, 464 (100–864) Bq kg−1. The corresponding absorbed dose rates in air from all those radionuclides were in the range of 17–81 nGy h−1 with a mean value of 46 nGy h−1 and did not exceed the world-wide average values. All dosimetric calculations were performed based on the guidance of UNSCEAR
2000 report [1]. 相似文献
6.
Synthesis,characterization and in vitro cytotoxicity of Pt-TiO<Subscript>2</Subscript> nanoparticles
T. López M. Alvarez R. D. González M. J. Uddin J. Bustos S. Arroyo A. Sánchez 《Adsorption》2011,17(3):573-581
The adverse toxicological profile of cisplatin (cis-dichlorodiammineplatinum (II)), characterized by nephrotoxicity and neurotoxicity
is the main factor that limit the clinical usefulness of this antineoplastic drug, specifically the possibility of applying
it in effective high-dose regimens. In order to overcome these disadvantages, many efforts in the search for new drugs have
been made. Due to this particularity, we obtained via sol–gel process Pt(acac)2–TiO2 (NPt) nanostructured materials with antitumoral activity to be used as an alternative in the treatment of cancer tumors.
The biocatalysts were prepared by the sol–gel route using the complex Pt(acac)2. Sol–gel parameters were controlled in order to obtain high platinum dispersion and particles in the nano-size range. TEM,
FTIR, N2 adsorption and XPS characterization studies of the samples were carried out. In order to investigate interactions between
the biocatalyst and DNA, agarose gel electrophoresis was performed, and we observed the formation of DNA adducts. 45 minutes
after contact, NPt completely degraded the DNA (cisplatin 120 minutes). These results demonstrate that using a metal supported
and dispersed over an inorganic biocompatible oxide, can be effectively used in the treatment of localized tumors. 相似文献
7.
8.
The lipid composition of four tissues, musculo-cutaneous, blood, internal organs, and gonads, from the marine worm Urechis unicinctus was studied. It was shown that the principal phospholipids (PL) in the studied tissues were phosphatidylcholine (PC) and
phosphatidylethanolamine (PE). Depending on the tissue type, the fraction of PC was 31.8–42.6%; PE, 16.1–25.7% (of total PL).
Blood contained a high percentage of lyso-PE (20.8%). The fatty-acid (FA) composition of the tissues consisted of C16, C18,
C20, and C22 families with different degrees of unsaturation. Eicosapentaenoic acid (20:5) had the highest percentage in all
tissues at 15.5–26.1%. Tissues with different functions such as musculo-cutaneous and gonads contained the same amounts of
20:5 FA, 26.1% (of total FA). The high content of polyunsaturated FA and, in particular, eicosapentaenoic FA in U. unicinctus confirmed that it was valuable as not only an energy source but also a source of PL and essential FA. 相似文献
9.
Negrusz A Bowen AM Moore CM Dowd SM Strong MJ Janicak PG 《Analytical and bioanalytical chemistry》2003,376(8):1198-1204
The objective of this paper was to determine how long after administration of benzodiazepine clonazepam (CLO), its major metabolite 7-aminoclonazepam (7-ACLO) could be detected in urine collected from 10 healthy volunteers who received a single 3-mg dose of Klonopin (clonazepam). Such data would be of great importance to law enforcement agencies trying to determine the best time interval for urine collection from a victim of drug-facilitated sexual assault in order to reveal drug use. A highly sensitive NCI–GC–MS method for the simultaneous quantitation of CLO and its major metabolite 7-ACLO in urine was developed and validated. The following urine samples were collected from each volunteer: one before CLO administration, and 6 h, and 1, 3, 5, 8, 10, 14, 21 and 28 days after. All urine samples (1 mL) were extracted following addition of the internal standard (D5-diazepam) and enzymatic hydrolysis (-glucuronidase) using solid-phase extraction columns. Standard curves for CLO (500–4000 pg mL–1) and 7-ACLO (50–2000 pg mL–1) were prepared by spiking aliquots of negative urine. The urine from every subject was still positive for 7-ACLO 14 days after administration of the drug. Eight of the ten volunteers had measurable amounts of the metabolite 21 days after administration. One volunteer was still positive 28 days after administration. Six of the volunteers had urine concentrations of 7-ACLO that peaked at 1 day after administration. One volunteer had the highest concentration of 7-ACLO at 3 days, two volunteers at 5 days, and one at 8 days. The range of concentrations detected was from 73.0 pg mL–1 to 183.2 ng mL–1. CLO was not detected in any of the samples. 相似文献
10.
V. N. Losev S. I. Metelitsa E. V. Elsuf’ev A. K. Trofimchuk 《Journal of Analytical Chemistry》2009,64(9):903-909
Silica gel chemically modified with N-(1,3,4-thiodiazole-2-thiol)-N′-propylurea extracted gold(III) from solutions in the range of 6 M HCl-pH 8 and silver(I) from nitric acid solutions in the
range of 6 M HNO3-pH 8 and 1–2 M HCl at 20°C with 99.0–99.9% recovery and a sorption equilibration time of 5 min. Platinum(II) was quantitatively
extracted at room temperature from solutions in the range of 4 M HCl-pH 8; the sorption equilibration time was 20 min. For
the quantitative extraction of platinum(IV), it should be reduced to platinum(II). The intense yellowish orange luminescence
(λmax (Au) = 575 nm, λmax (Ag) = 550 nm, and λmax(Pt) = 620 nm) of surface complexes at 77 K under UV irradiation was used in the development of procedures for the low-temperature
sorption-luminescence determination of gold, silver, and platinum. The detection limits were 0.15 (Au), 0.1 (Ag), and 0.05
μg (Pt) per 0.1 g sorbent. The calibration function was linear to 50 (Au, Ag) or 80 μg (Pt) per 0.1 g sorbent. The relative
standard deviation in the determination of more than 5 μg of a metal was no higher than 6%. The sorption-luminescence determination
procedures were tested in the determination of gold in gold-containing concentrates and their processing products and platinum
in alumina-platinum catalysts. 相似文献
11.
The formation and dissolution of tin ad-layers on polycrystalline platinum were analysed by cyclic voltammetry in aqueous
10–4 M tin(II)/1 M sulfuric acid in the 0.05–0.70 V versus RHE range. At this concentration level it was possible to observe that
platinum sites involving (110) planes are mainly related to tin underpotential deposition. In contrast to previous results,
no irreversible adsorption was found in the course of the electrodeposition. Thermodynamic adsorption parameters were calculated
from the potential dependence of tin surface coverage. Catalytic properties of this new surface were studied on the basis
of oxygen electroreduction as a model. Kinetic runs were performed with rotating ring-disk electrodes on bare and tin-modified
platinum surfaces. Molecular oxygen reduction on tin-modified platinum takes place through the production of both water and
hydrogen peroxide. This interpretation was confirmed by calculating the reaction order with respect to oxygen.
Electronic Publication 相似文献
12.
V. N. Mitkin A. A. Galitsky T. M. Korda 《Fresenius' Journal of Analytical Chemistry》1999,365(4):374-376
In order to develop a reliable method for the platinum group metals (PGMs) determination in ores of organic origin like carbonaceous
black shale a decomposition method with fluoroxidants like BrF3 and KBrF4 was established which avoids the commom losses of PGM organometallic compounds by volatilazation or chemisorption. The recovery
from different trapping solutions is discussed. Platinum metals are evidently found in the carbonaceous black shale ores from
the “Natalka” deposit situated in the Magadan area. PGMs are very inhomogenously distributed in the ores and ore concentrates
and their total contents in ore are 5–18 g/t. The carbonaceous concentrate of black shale ore contains up to 23 g/t of the
sum of platinum metals. ≥ 8% of the sum of platinum and palladium contained in this carbonaceous concentrate are soluble in
organic solvents.
Received: 16 July 1998 / Revised: 16 April 1999 / Accepted: 5 May 1999 相似文献
13.
In order to develop a reliable method for the platinum group metals (PGMs) determination in ores of organic origin like carbonaceous
black shale a decomposition method with fluoroxidants like BrF3 and KBrF4 was established which avoids the commom losses of PGM organometallic compounds by volatilazation or chemisorption. The recovery
from different trapping solutions is discussed. Platinum metals are evidently found in the carbonaceous black shale ores from
the “Natalka” deposit situated in the Magadan area. PGMs are very inhomogenously distributed in the ores and ore concentrates
and their total contents in ore are 5–18 g/t. The carbonaceous concentrate of black shale ore contains up to 23 g/t of the
sum of platinum metals. ≥ 8% of the sum of platinum and palladium contained in this carbonaceous concentrate are soluble in
organic solvents.
Received: 16 July 1998 / Revised: 16 April 1999 / Accepted: 5 May 1999 相似文献
14.
Amol Mhatre Vivek Chavan P. C. Kalsi V. S. Nadkarni 《Journal of Radioanalytical and Nuclear Chemistry》2010,286(1):99-101
The gamma irradiation effects on the bulk etch rate, V
b of an indigenously prepared new nuclear track detector which is a copolymer of allyl bis-(2-nitroxy-ethyl) carbomate (ABNEC)
and allyl diglycol carbonate (ADC) [ABNEC:ADC (1:9)] were studied in the dose range of 25.0–250.0 kGy and etching temperature
range of 60–80 °C. The bulk etch rates increase and the activation energy values for bulk etching of gamma-irradiated detectors
decrease with the increase in gamma dose indicating the scission of the detector. UV–visible spectra of the unirradiated and
the irradiated films were also taken to explore the possibility of using this new detector for gamma dose measurements. 相似文献
15.
A simple HPLC-MS/MS method for simultaneous determination of loureirin A and loureirin B in rat urine, feces, and bile after
oral administration of 10.6 g/kg of longxuejie (one rare traditional Chinese medicinal herb) was developed for the first time.
The analytes and buspirone (internal standard) were separated on a C5 column with acetonitrile–water (containing 0.1% formic acid) as mobile phase at a flow rate of 0.4 min/mL. The detector was
a Q-trap™ mass spectrometer with an electrospray ionization interface operating in the multiple reaction monitoring mode.
Calibration curves of loureirin A in rat urine, feces, and bile were linear over the concentration range of 1.00–5,000 ng/mL.
Loureirin B in rat urine, feces, and bile ranged between 0.08 and 20, 0.20 and 20, and 0.10 and 500 ng/mL, respectively. Validation
revealed that the method was specific, accurate, and precise. The fully validated method was applied to the excretion study
of loureirin A and loureirin B in rats. After oral administration of 10.6 g/kg longxuejie, cumulative excretion amount of
loureirin A and loureirin B in rat urine were 2.94 ± 0.81 and 0.36 ± 0.16 μg at 72 h, respectively. Of the total dose, 5.35%
of loureirin A and 5.46% of loureirin B were excreted from feces at 60 h. The cumulative amounts of loureirin A and loureirin
B in rat bile reached 4.49 ± 0.98 and 5.11 ± 0.83 μg, respectively, at 36 h after dosing, accounting for 0.054% and 0.056%
of the total dose. 相似文献
16.
Xiao-Li Liu Hong-Fang Zhang Guang-Jun Qiao Wei Cao Jian-Bin Zheng 《Chromatographia》2008,67(1-2):147-150
A rapid, sensitive, and specific method for quantification of olmesartan, the prodrug of olmesartan medoxomil, in human plasma,
using zidovudine as internal standard, is described. Sample preparation involved a simple solid-phase extraction procedure.
The extract was analyzed by high-performance liquid chromatography coupled to electrospray tandem mass spectrometry (LC–MS–MS).
Chromatography was performed isocratically on a 5 μm C18 analytical column (50 mm × 4.6 mm i.d.) with water–acetonitrile–formic acid 20:80:0.1 (v/v) as mobile phase. The response to olmesartan was a linear function of concentration over the range 4.82–1,928 ng mL−1. The lower limit of quantification in plasma was 4.82 ng mL−1. The method was successfully applied in a bioequivalence study of an olmesartan formulation after administration as a single
oral dose. 相似文献
17.
Benjamin W. Harper Anwen M. Krause‐Heuer Maxine P. Grant Madhura Manohar K. Benjamin Garbutcheon‐Singh Janice R. Aldrich‐Wright Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(24):7064-7077
The approved platinum(II)‐based anticancer agents cisplatin, carboplatin and oxaliplatin are widely utilised in the clinic, although with numerous disadvantages. With the aim of circumventing unwanted side‐effects, a great deal of research is being conducted in the areas of cancer‐specific targeting, drug administration and drug delivery. The targeting of platinum complexes to cancerous tissues can be achieved by the attachment of small molecules with biological significance. In addition, the administration of platinum complexes in the form of platinum(IV) allows for intracellular reduction to release the active form of the drug, cisplatin. Drug delivery includes such technologies as liposomes, dendrimers, polymers and nanotubes, with all showing promise for the delivery of platinum compounds. In this paper we highlight some of the recent advances in the field of platinum chemotherapeutics, with a focus on the technologies that attempt to utilise the cytotoxic nature of cisplatin, whilst improving drug targeting to reduce side‐effects. 相似文献
18.
The accumulation of CO
2
-
radicals in γ-irradiated porcine, chicken, bovine, walleye pollack, and navaga bone tissues and chicken eggshells was studied
by EPR spectroscopy for the purpose of detecting irradiated food and evaluating the dose absorbed during its radiation processing.
It was found that, in the dose range 0–10 kGy, the concentration of radicals is a linear function of dose, and the variation
coefficient of the radiationchemical yield of radicals is no higher than 30% for bone tissues from various biological species.
The applicability of the additive dose method to the EPR dosimetry of irradiated beef was examined. A linear regression model
used in the additive dose method was found to give overestimated results, as compared with an exponential fitting model. 相似文献
19.
A column preconcentration method has been established for the spectrophotometric determination of traces of nitrite using
diazotization and coupling on an naphthalene-tetradecyldimethylbenzylammonium (TDBA)-iodide (I) adsorbent. Nitrite ion reacts
with sulfanilic acid (SA) in the pH range 1.8–3.0 for the SA-1-naphthol system and in the pH range 2.3–3.2 for the SA-1-naphthylamine-4-sulfonate
system (SA-NAS system) in hydrochloric acid medium to form water-soluble colourless diazonium cations. These cations were
coupled with 1-naphthol in the pH range 1.6–4.6 and with NAS in the pH range 2.6–5.0 to be retained on naphthalene-TDBA-I
packed in a column. The solid mass was dissolved from the column with 5 mL of dimethylformamide (DMF) and the absorbance measured
at 418 nm for the SA-1-naphthol system and at 485 nm for the SA-NAS system. The calibration curve was linear over the concentration
range 0.02–0.87 mg/L for SA-1-naphthol and 0.02–0.80 mg/L in the sample for SA-NAS. The molar absorptivity was calculated
to be 1.70×104 L mol-1 cm-1 for SA-1-naphthol and 1.66×104 L mol-1 cm-1 for SA-NAS. The detection limits were found to be 0.014 and 0.016 mg/L for SA-1-naphthol and SA-NAS, respectively. The preconcentration
factors were 8 and 6 for SA-1-naphthol and SA-NAS, respectively. Replicate determinations of seven sample solutions containing
6.6 μg of nitrite for SA-1-naphthol and 5.3 μg of nitrite for SA-NAS gave mean absorbances of 0.486 and 0.382 with relative
standard deviations of 0.49 and 0.58%, respectively. Interferences due to various foreign ions have been studied and the method
has been applied to the determination of 27–65 μg/L levels of nitrite in natural waters. The recovery and relative standard
deviation for water samples were 98–102% and 0.49–0.58% for both systems.
Received: 1 December 1995/Revised: 22 April 1996/Accepted: 22 April 1996 相似文献
20.
Miles DR Mesfin M Mody TD Stiles M Lee J Fiene J Denis B Boswell GW 《Analytical and bioanalytical chemistry》2006,385(2):345-356
Liquid chromatography–fluorescence (LC–FLS), liquid chromatography–tandem mass spectrometry (LC–MS/MS) and inductively coupled
plasma–mass spectrometry (ICP-MS) methods were developed and validated for the evaluation of motexafin gadolinium (MGd, Xcytrin)
pharmacokinetics and biodistribution in plasma and tissues. The LC–FLS method exhibited the greatest sensitivity (0.0057 μg
mL−1), and was used for pharmacokinetic, biodistribution, and protein binding studies with small sample sizes or low MGd concentrations.
The LC–MS/MS method, which exhibited a short run time and excellent selectivity, was used for routine clinical plasma sample
analysis. The ICP–MS method, which measured total Gd, was used in conjunction with LC methods to assess MGd stability in plasma.
All three methods were validated using human plasma. The LC–FLS method was also validated using plasma, liver and kidneys
from mice and rats. All three methods were shown to be accurate, precise and robust for each matrix validated. For three mice,
the mean (standard deviation) concentration of MGd in plasma/tissues taken 5 hr after dosing with 23 mg kg−1 MGd was determined by LC–FLS as follows: plasma (0.025±0.002 μg mL−1), liver (2.89±0.45 μg g−1), and kidney (6.09±1.05 μg g−1). Plasma samples from a subset of patients with brain metastases from extracranial tumors were analyzed using both LC–MS/MS
and ICP–MS methods. For a representative patient, ≥90% of the total Gd in plasma was accounted for as MGd over the first hour
post dosing. By 24 hr post dosing, 63% of total Gd was accounted for as MGd, indicating some metabolism of MGd. 相似文献