Ograniczanie wyników
Czasopisma help
Autorzy help
Lata help
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 53

Liczba wyników na stronie
first rewind previous Strona / 3 next fast forward last
Wyniki wyszukiwania
Wyszukiwano:
w słowach kluczowych:  bioavailability
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 3 next fast forward last
EN
In this study, a UPLC-MS/MS method was developed for determination of pancratistatin in the mouse blood, and the pharmacokinetics of pancratistatin in mice after intravenous (5 mg kg1) and intragastric (15mg kg1) administration was studied. HSS T3 column was used for separation with mobile phases of acetonitrile and 0.1% formic acid using gradient elution procedure. The blood sample was treated by protein precipitant with acetonitrile, midazolam was used as internal standard (IS). Multiple reaction monitoring mode (MRM) was used for quantitative analysis, m/z 326.2→83.8 for pancratistatin and m/z 326.2→291.4 for IS in electrospray (ESI) positive interface. It showed a good linear in the range of 10–4,000 ng mL1 (r > 0.998); the intra-day and inter-day precision was <15%, and the accuracy was 93%–105%. The recovery was better than 82%, and the matrix effect was 94%–105%. The developed UPLC-MS/MS method was fast, selective, and suitable for the pharmacokinetics of pancratistatin in mice
2
Content available remote Pharmacokinetics and bioavailability of curdione in mice by UPLC-MS/MS
EN
A UPLC-MS/MS method was developed to determinate curdione in the mouse blood, and the pharmacokinetics of curdione in mice after intravenous (5 mg kg⁻¹) and oral (20 mg kg⁻¹) administration were studied. The HSS T3 column was used for separation, and column temperature was set at 40 °C. Multiple reaction monitoring (MRM) mode were used for determination of curdione. Blood samples were taken from the caudal vein of Institute of Cancer Research (ICR) mice after administration of curdione. It showed a good linear relationship in the range of 1–500 ng mL⁻¹ (r > 0.998); the intra-day precision was <13%, the inter-day precision was <15%, and the accuracy was 90%–105%, the recovery was >77%, and the matrix effect was 97%–107%. The half-life was relatively short, and the bioavailability was 6.5%. The developed method was suitable for the pharmacokinetics of curdione in mice.
EN
Modafinil has a strong and long-lasting awakening effect. Short-term use can improve cognitive and work efficiency. Therefore, it has been known to be abused by students and parents as a “smart drug.” It is in the first category of psychotropic drugs and strictly controlled. To detect modafinil in rat plasma and study the differences in the pharmacokinetics of modafinil between oral and sublingual administration in rats, an ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed. Rats were injected with modafinil by oral gavage and sublingual vein, respectively, blood was collected within a certain period, and the plasma was obtained by centrifugation. Midazolam was used as the internal standard, and the concentration of modafinil in the plasma was determined by UPLC-MS/MS, where a drug-time curve was created to calculate the pharmacokinetic parameters. The standard curve for modafinil ranged from 1 to 2000 ng mL⁻¹ with good linearity. The intra-day accuracy of modafinil was between 86% and 104%, and the intra-day accuracy was between 90% and 103%. Intra-day precision (RSD%) was less than 15%, inter-day precision (RSD%) was less than 15%. The matrix effect was between 93% and 102%, and the recovery was greater than 91%. The UPLC-MS/MS method established in this work has good selectivity and high sensitivity, and the UPLC-MS/MS method was successfully applied to the pharmacokinetics of modafinil by oral gavage and sublingual injection in rats. The bioavailability of modafinil was calculated to be 55.8%.
EN
A simple, rapid, and sensitive method based on UPLC-MS/MS was developed to determine spiraeoside in mouse blood, and was applied to the pharmacokinetics and bioavailability of spiraeoside after mice after intravenous (a dose of 5 mg kg⁻¹) and oral (a dose of 20 mg kg⁻¹) administration. On HSS T3 column set at 40 °C, chromatographic separation was obtained with the mobile phase of acetonitrile and 0.1% formic acid using the gradient elution. Spiraeoside and internal standard (IS) were quantitatively analyzed using multiple reaction monitoring (MRM) mode in electrospray (ESI) positive interface. The MRM mode was monitoring the fragmentation of m/z 465.4→303.1 and m/z 451.3→ 289.2 for spironoside and IS, respectively. The results showed a good linear relationship was in the concentration range of 1–200 ng mL⁻¹ (r > 0.998) and the lower limit of quantification (LLOQ) was 1.0 ng mL⁻¹. The intra- and the inter-day precision (RSD%) of the method was within 14.0%, and the accuracy ranged from 90.0% to 115.0%. The extraction recovery of spriaeoside was better than 63.0%, and the matrix effects were in the range of 86%–98%. It also showed the half-life was short, and the absolute bioavailability was 4.0% in mice. Therefore, the established UPLC-MS/MS method was suitable for the pharmacokinetic and bioavailability study of spiraeoside in mice.
EN
This study examined the effect of water column hypoxia on the distribution and geochemical fractionation of trace metals in the seasonally hypoxic coastal environment in the southeastern Arabian Sea. Water and surface sediments were collected fortnightly from the Alappuzha mud bank between April and August 2016, which covered the pre-upwelling and upwelling seasons. The water column was warm and well-oxygenated during April–May. During June–August, the incidence of cold and hypoxic water indicated strong coastal upwelling prevailed in the entire study domain. The Fe and Mn content in sediments gradually decreased, because of the reductive dissolution and subsequent release of metals under hypoxia. The concentration of metals such as Ni, Zn and V decreased substantially under oxygen deficiency, whereas Cr showed marked enrichment in sediments. Although the geochemical forms of trace metals displayed the dominance of residual fractions (inert), the reactive non-residual metal forms (exchangeable, Fe/Mn-(oxy)hydroxide, and organic matter/sulphide bound) showed considerable variability under hypoxia. The shift from Fe/Mn-(oxy)hydroxide bound to organic matter and sulphide bound was evident during hypoxia. Cr exhibited a strong affinity towards organic matter and sulphide, and Pb and Zn showed relatively high association towards the Fe/Mn-(oxy)hydroxide phase. Even with such a phase shift induced by the hypoxic conditions, the concentrations of these metals remained within the normal background levels, indicating the pristine nature of the mud bank environment.
EN
A rapid and simple UPLC-MS/MS method was developed to determine toddalolactone in mouse blood and applied to measure the pharmacokinetics of toddalolactone in mice. Blood samples were first preprocessed by ethyl acetate liquid-liquid extraction. Oxypeucedanin hydrate (internal standard, IS) and toddalolactone were gradient eluted from a UPLC BEH C18 column using a mobile phase consisting of acetonitrile and water (0.1% formic acid). Using electrospray ionization (ESI) as the ionization source, multiple reaction monitoring was used to detect the precursor and product ions of m/z 309.2 and 205.2, respectively, for toddalolactone and of m/z 305.1 and 203.0 for IS, respectively, for quantitative detection. A calibration curve was run over the concentration range of 5–4,000 ng/mL (r > 0.995). The matrix effects ranged from 93.5 to 98.4%, and the recovery was higher than 77.3%. The precision was less than 13%, and the accuracy ranged from 90.9 to 108.4%. The developed UPLC-MS/MS method was successfully used for measuring the pharmacokinetics of toddalolactone in mice after oral (20 mg/kg) and intravenous administration (5 mg/kg), and the absolute bioavailability of toddalolactone was 22.4%.
EN
Narciclasine is a 7-hydroxy derivative of lycorisidine. It was the first alkaloid isolated from the stem of narcissus (Amaryllidaceae) in 1967. Six mice were given narciclasine (5 mg/kg) by intravenous administration. A UPLC-MS/MS method was developed to determine narciclasine in mouse blood. Tectorigenin (internal standard, IS) and narciclasine were gradient eluted by mobile phase of methanol and 0.1% formic acid in a BEH C18 column. The multiple reaction monitoring (MRM) of m/z 308.1→248.1 for narciclasine and m/z 301.1→286.0 for IS with an electrospray ionization (ESI) source was used for quantitative determination. The calibration curve ranged from 1 to 6,000 ng/mL. The accuracy was from 92.5 to 107.3%, and the matrix effect was between 103.6 and 107.4%. The developed UPLC-MS/MS method was successfully applicated to a pharmacokinetic study of narciclasine in mice after intravenous administration (5 mg/kg).
EN
Eugenitin is a non-volatile chromone derivative which is always found in dried flower buds of Syzygium aromaticum L. (Merr.) & L.M. Perry. Until now, there were no reports about the pharmacokinetics of eugenitin in biological fluids. A UPLC-MS/MS method developed to determine eugenitin in mouse blood. The blood samples were prepared by protein precipitation with acetonitrile. Chrysin (internal standard, IS) and eugenitin were gradient eluted by mobile phase of acetonitrile and water (0.1% formic acid) in a BEH C18 column. The multiple reaction monitoring (MRM) of m/z 221.1→206.0 for eugenitin and m/z 255.1→152.9 for IS with an electrospray ionization (ESI) source was used for quantitative detection. The calibration curve ranged from 0.5 to 500 ng/mL (r > 0.995). The accuracy ranged from 98 to 113%, the precision was less than 12%, and the matrix effect was between 86 and 94%, the recovery was better than 81%. The developed method was successfully used for pharmacokinetics of eugenitin in mice after intravenous (5 mg/kg) and oral (20 mg/kg) administration, and the absolute availability of eugenitin was 12%.
9
Content available remote Compost produced with addition of sewage sludge as a source of Fe and Mn for plant
EN
Direct application of sewage sludge to soil is controversial due to, among others, its highly variable composition, odour, and risks for health. The obtained composts with the addition of sewage sludge were tested for the contents and availability of manganese and iron. Once composts were applied to the soil, their effect on the content and availability of Mn and Fe in soil and bioaccumulation in the plant were determined. The addition of sewage sludge enriched composts with manganese and iron, but did not increase the content of water-extracted forms of Mn and Fe. The compost with addition of biochar had more organic matter-bound forms of Mn and Fe. Composts amended with sewage sludge had lower effect on the amount of Poa pratensis L. biomass than maize straw compost. The content of Mn and Fe in Poa pratensis L. was in the range permissible for biomass used as fodder. Smaller addition of all composts to the soil significantly increased the content of mobile manganese forms; however, neither the type nor the dose had effect on the content of iron mobile forms. There was no significant differences in the content of organic matter-bound forms of Mn and Fe in soil after the application of composts.
EN
Palmatine is a compound with good water solubility extracted from Coptis chinensis, Fibraurea recisa Pierre, Cortex Phellodendri Chinensis. Palmatine has good antibacterial activity and mainly used for the treatment of bacterial dysentery, gynecological inflammation, surgical infection, and conjunctivitis. It has anti-diabetic, anti-oxidant, and cognitive-enhancing activities. In this study, we used UPLC-MS/MS to determinate palmatine in rat plasma, and investigated its pharmacokinetics. Coptisine was utilized as an internal standard (IS), and acetonitrile precipitation method was used to process the plasma samples. Chromatographic separation was achieved using a UPLC BEH C18 column using mobile phase of acetonitrile- 0.1% formic acid with gradient elution. Electrospray ionization (ESI) tandem mass spectrometry in multiple reaction monitoring (MRM) mode with positive ionization was applied. The results indicated that within the range of 1–500 ng/mL, linearity of palmatine in rat plasma was acceptable (r > 0.995), and the lower limit of quantification (LLOQ) was 1 ng/mL. Intra-day and inter-day precision RSD of palmatine in rat plasma were less than 14%. Accuracy range was between 93.7 and 107.1%, and matrix effect was between 101.6 and 109.4%. The method was successfully applied in the pharmacokinetics of palmatine in rats after oral and intravenous administration. The absolute bioavailability of the palmatine was 15.5% in rats.
11
Content available remote Pharmacokinetics and bioavailability of liensinine in mouse blood by UPLC-MS/MS
EN
Liensinine is a bisbenzyltetrahydroisoquinoline alkaloid extracted from lotus (Nelumbo nucifera GAERTNER., Nelumbonaceae), especially in its embryo loti “Lien Tze Hsin” (green embryo of mature seed). A rapid and simple UPLC-MS/MS method was developed to determine liensinine in mouse blood and its application to a pharmacokinetic study. The blood samples were preprocessed by protein precipitation using acetonitrile. Midazolam (internal standard, IS) and liensinine were gradient eluted by mobile phase of methanol and water (0.1% formic acid) in a Waters UPLC BEH C18 column. The multiple reaction monitoring of m/z 611.3 → 206.1 for liensinine and m/z 326.2 → 291.1 for IS with an electrospray ionization (ESI) source was used for quantitative detection. The calibration curve ranged from 0.5 to 400 ng/mL (r > 0.995). The accuracy ranged from 92.2 to 108.2%, the precision of intra-day and inter-day was less than 14%, and the matrix effect was between 100.0% and 109.6%, the recovery was better than 71.0%. The developed UPLC-MS/MS method was successfully used for a pharmacokinetic study of liensinine in mice after oral (5 mg/kg) and intravenous administration (1 mg/kg), and the absolute availability of liensinine was 1.8%.
EN
Sarecycline is a narrow-spectrum antibiotic for the treatment of acne, which is a chronic inflammatory disease of the hair follicle sebaceous glands. In the study, UPLC-MS/MS was used to establish a rapid and accurate analytical method. The sarecycline was determined with poziotinib as internal standard (IS) in rat plasma. An ACQUITY UPLC HSS T3 column (2.1 × 100 mm, 1.8 μm) could performe chromatographic separation with the mobile phase (methanol: water of 0.1% formic acid) with gradient elution. The ions of target fragment were m/z 488.19→410.14 for sarecycline and m/z 492.06→354.55 for poziotinib, which could quantify the electrospray ionization of positive multiple reaction monitoring (MRM) mode. The linear calibration curve of the concentration range was 1–1,000 ng/mL for sarecycline with a lower limit of quantification (LLOQ) of 1 ng/mL. The mean recovery was between 82.46 and 95.85% for sarecycline and poziotinib in rat plasma. RSD for precision of inter-day and intra-day were between 3.24 and 13.36%, and the accuracy ranged from 105.26 to 109.75%. The developed and validated method was perfectly used in the pharmacokinetic study and bioavailability of sarecycline after intravenous and oral administration in rats.
13
Content available remote Determination and pharmacokinetics of calycanthine in rat plasma by UPLC-MS/MS
EN
Calycanthine is an important class of alkaloids extracted and isolated from the roots, leaves, flowers and fruits of Chimonanthus praecox. In this work, the UPLC-MS/MS method was used for determination of calycanthine in rat plasma, and the pharmacokinetics in rats were investigated. Midazolam was used as an internal standard (IS), and methanol precipitation method was used to pretreatment the rat plasma samples. Chromatographic separation was achieved on a UPLC BEH C18 (50 3 2.1 mm, 1.7 mm) column with the mobile phase of methanol- 0.1% formic acid aqueous solution with gradient elution. Multiple reaction monitoring (MRM) mode with positive ionization was applied for quantitative analysis, m/z 347.3 → 246.7 and 326.2 → 291.4 for calycanthine and IS, respectively. The results indicated that within the range of 1–200 ng/mL, linearity of calycanthine in rat plasma was good (r > 0.995), and the lower limit of quantification (LLOQ) was 1 ng/mL. Accuracy range was between 90.6 and 109.4%, precision (RSD) of calycanthine was less than 14%. The matrix effect was between 97.9% and 105.4%, the recovery was better than 85.6%. The developed UPLC-MS/MS method was successfully applied in the pharmacokinetics of calycanthine in rats after oral and intravenous administration. The absolute bioavailability of the calycanthine was 37.5% in rats.
14
EN
The geochemical fractionation of heavy metals, including Mn, Fe, Cu, Pb, Zn, Cd and Ni, collected from the surface sediments of the Jeddah coastal zone of the Red Sea in Saudi Arabia was determined using a sequential extraction technique. The data obtained from the five fractions indicated that the concentration of metals varies among different locations in the study area. The total metal concentrations (%) in the exchangeable (F1), carbonate (F2), reducible (F3) and organic-bound (F4) fractions were measured to determine the mobility of each studied metal. The sum of the two fractions F3 and F4 represented 70% of the Cu, 72% of the Zn and 36% of the Pb. However, the sum of the three fractions F2, F3 and F4 represented 76%, 74%, 68% and 58% of the Cd, Ni, Fe and Mn, respectively. Approximately 46% of the total copper was related to organics, which could reflect a high mobility of copper in these sediments. The maximum mobility of metals in the sediments was confirmed by the bioavailability factor (BF), which was within the ranges of 0.47-0.93, 0.34-0.92, 0.62-0.95, 0.69-0.95, 0.24-0.82, 0.54-0.98, and 0.60-0.95 for Fe, Mn, Cu, Zn, Pb, Cd, and Ni, respectively. Based on the BF, the metals exhibited the following order: Cu ≈ Zn > Cd ≈ Ni ≈ Fe > Mn > Pb. The high levels of BF for the studied metals could reflect the potential for toxic metals to be easily released into the marine environment. The risk assessment code for Cd showed a medium risk in five sediment samples of the northern and southern regions and a high risk to the aquatic environment in the other sediment samples. However, the speciation of Fe, Mn, Cu, Zn, Pb and Ni in the studied sediments exhibited low to medium risks to the aquatic environment.
EN
An ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) method was established to determine the hapepunine in mouse blood, and the pharmacokinetics of hapepunine after intravenous (1.0 mg/kg) and intragastric (2.5, 5, and 10 mg/kg) administrations was studied. Delavinone was used as an internal standard. The UPLC ethylene bridged hybrid (BEH) C18 column was used for chromatographic separation. The mobile phase consisted of acetonitrile and 0.1% formic acid with a gradient elution flow rate of 0.4 mL/min. Multiple reaction monitoring (MRM) mode was used for quantitative analysis of hapepunine in electrospray ionization (ESI) positive interface. Proteins from mouse blood were removed by acetonitrile precipitation. The verification method was established in accordance with the US Food and Drug Administration (FDA) bioanalytical method validation guidelines. In the concentration range of 1–1000 ng/mL, the hapepunine in the mouse blood was linear (r2 > 0.995), and the lower limit of quantification was 1.0 ng/mL. In the mouse blood, the intra-day precision coefficient of variation (CV) was less than 12%, the inter-day precision CV was less than 14%. The accuracy ranged from 91.7% to 109.3%. The average recovery was higher than 76.7%, and the matrix effect was between 86.0% and 106.4%. The UPLC–MS/MS method was sensitive, rapid, and selective and was successfully applied to the pharmacokinetic study of hapepunine in mice. The absolute bioavailability of hapepunine was 22.0%.
EN
Byakangelicol is one of coumarins from Baizhi and has been shown to inhibit the release of PGE2 from human lung epithelial A549 cells in a dose-dependent manner. A sensitive ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) method was developed and full validated for the quantification of byakangelicol in rat plasma. The pharmacokinetics of byakangelicol after both intravenous (5 mg/kg) and oral (15 mg/kg) administrations were studied. Chromatographic separation was performed on an ultra-performance liquid chromatography ethylene bridged hybrid (UPLC BEH) C18 column with acetonitrile and 0.1% formic acid as the mobile phase at a flow rate of 0.4 mL/min; fargesin was used as the internal standard (IS). The following quantitative analysis of byakangelicol was utilized in the multiple reaction monitoring mode. The samples were extracted from rat plasma via protein precipitation using acetonitrile. In the concentration range of 1–2000 ng/mL, the method correlated linearity (r > 0.995) with a lower limit of quantitation (LLOQ) of 1 ng/mL. Intra-day precision was less than 11%, and inter-day precision was less than 12%. The accuracy was between 92.0% and 108.7%, the recovery was better than 89.6%, and the matrix effect was between 85.9% and 98.6%. The method was successfully applied to a pharmacokinetic study of byakangelicol after intravenous and oral administration, and the absolute bioavailability was 3.6%.
PL
Badanie bioprzyswajalności składników aktywnych jest bardzo istotne dla prawidłowej oceny jakości procesu żywienia oraz projektowania produktów o wysokich walorach odżywczych. Jednym z wielu czynników mających wpływ na zmiany w biodostępności jest obróbka technologiczna surowca, w tym techniki wykorzystujące wysokie ciśnienie. Składniki pochodzenia roślinnego o właściwościach przeciwutleniających o charakterze hydrofilowym to między innymi witamina C, kwas foliowy i związki z grupy polifenoli. Wysokie ciśnienie hydrostatyczne może powodować uszkodzenia tkanek roślinnych, a w konsekwencji zwiększać ekstraktywność związków z matrycy oraz ich kontakt z enzymami hydrolizującymi. Z kolei spadek bioprzyswajalności może wynikać ze wzrostu lepkości pod wpływem ciśnienia oraz uwalniania enzymów oksydoredukcyjnych obecnych w tkance roślinnej. Publikacje dotyczące wpływu technik wysokociśnieniowych na biodostępność antyoksydantów hydrofilowych są nieliczne i nie zawsze jednoznaczne.
EN
The study of bioavailability and bioaccessibility of active ingredients is very important for the proper assessment of the quality of the nutrition and design of products with high nutritional value. One of the many factors influencing the changes in bioaccessibility is the technological processing of the raw material, including high pressure techniques. Hydrophilic ingredients of plant origin with antioxidant properties include, among others, vitamin C, folic acid and polyphenol compounds. High hydrostatic pressure may cause damage of plant tissues, and as a consequence, increase the extraction of compounds from the matrix and their contact with hydrolysing enzymes. On the other hand, the decrease in bioavailability may result from the increase in viscosity under pressure and release of oxidoreductive enzymes present in the plant tissue. Publications about the impact of high-pressure techniques on the bioavailability of hydrophilic antioxidants are few and not always unequivocal.
PL
Bioprzyswajalność antyoksydantów obecnych w żywności jest ściśle powiązana z rodzajem związku, jego lokalizacją w tkance oraz składem matrycy. Skutecznym narzędziem badania biodostępności składników żywieniowych są modele symulacji trawienia żołądkowo-jelitowego in vitro. Według najnowszych badań metody przetwarzania żywności wykorzystujące wysokie ciśnienia mogą zwiększać bioprzyswajalność i biodostępność lipofilowych antyoksydantów, zwłaszcza karotenoidów i tokoferoli obecnych w produktach owocowych i warzywnych. Wysokie ciśnienia hydrostatyczne oraz homogenizacja wysokociśnieniowa oddziaływają na strukturę tkanek roślinnych, powodując uszkodzenia naturalnych barier komórkowych i ułatwiając uwalnianie lipofilowych składników z matrycy żywności, a następnie rozpuszczanie ich w tłuszczach. Niejednoznaczne wyniki badań, wynikające z dużej ilości czynników wpływających na bioprzyswajalność, skłaniają do prowadzenia dalszych badań w tej dziedzinie.
EN
The bioavailability of antioxidants present in foods is closely related to the type of compound, its location in the tissue and the composition of the food matrix. The in vitro model of gastrointestinal digestion is an effective tool for studying the bioaccessibility of nutrients. According to the current research high pressure methods of food preservation can increase the bioavailability and bioaccessibility of lipophilic antioxidants, mainly carotenoids and tocopherols, present in fruit and vegetable products. High hydrostatic pressure and high-pressure homogenization affect the structure of plant tissues, causing the damage of natural cellular barriers and facilitating the release of lipophilic compounds from the food matrix and subsequent dissolution in fats. Ambiguous results of the latest research, resulting from a large number of factors affecting bioavailability, lead to further studies in this field.
EN
The study was performed to determine the bioavailable amounts of cadmium, lead, and zinc in the soils contaminated over the years of Zn-Pb ore mining and processing near Olkusz, Poland, and to identify the environmental risk (RAC) associated with the occurrence of the most mobile forms of these metals in the soil. The authors analyzed the topsoil samples for the basic physical and chemical parameters, as well as for total metal content (by aqua regia extraction), and for percentage of 1 M HCl- and 1 M NH4NO3 – extractable fractions. The results were compared with the content of these metals in a common grass species, Agrostis capillaris. In the study region, the Cd, Pb, and Zn contents were (respectively, in mg∙kg-1): 0.5–33.5, 2–529, and 4–7877. This means that in more than 24%, 30%, and 38% of samples, respectively, the metal content exceeded the limits defined by the Polish Environment Minister’s Regulation of September 9, 2002, with nearly 24% of soil samples contaminated by all three metals. On the basis of the Environment Minister’s Regulation of September 1, 2016, which is currently in force, and using the allowed limits for subgroup IV (industrial land), set at 15 mg∙kg-1 for Cd, 600 mg∙kg-1 for Pb, and 2000 mg∙kg-1 for Zn, the analysis also found the excessive metal content in a considerable percentage of the topsoil samples (33%, 13%, and 38%, respectively). The content of the studied elements in a common grass species, Agrostis capillaris, was significantly higher than the so-called natural content. A strict association was found between the total Cd, Pb, and Zn content, and the potentially available 1 M HCl – extractable fraction. The environmental risk presented by the content of mobile Cd, Pb, and Zn forms, assessed in all the studied soil samples using Risk Assessment Codes (RAC), demonstrates very high environmental risk associated with Cd, high environmental risk connected with Zn, and moderate environmental risk related to Pb.
20
Content available remote Pharmacokinetics of 8-O-acetylharpagide in mouse blood by UPLC–MS/MS
EN
8-O-Acetylharpagide is the main active component of the herb Ajuga decumbens, which possesses anti-tumor, anti-virus, and anti-inflammation properties. In this study, ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) was used to measure the concentration of 8-O-acetylharpagide in mouse blood, with subsequent investigation of the pharmacokinetics of the drug after intravenous or oral administration. Shanzhiside methyl ester was used as an internal standard, and the acetonitrile precipitation method was used to process the blood samples. Chromatographic separation was achieved using an ultra-performance liquid chromatography ethylene-bridged hybrid (UPLC BEH) column (2.1 mm × 50 mm, 1.7 μm) with a gradient methanol–water mobile phase (containing 0.1% formic acid). The flow rate was 0.4 mL/min, and the elution time was 5.0 min. 8-O-Acetylharpagide was quantitatively measured using electrospray ionization (ESI) tandem mass spectrometry in multiple reaction monitoring (MRM) mode with positive ionization. The result indicated that, within the range of 5–500 ng/mL, the linearity of 8-O-acetylharpagide in mouse blood was satisfactory (r > 0.995), and the lower limit of quantification (LLOQ) was 5 ng/mL. Intra-day precision relative standard deviation (RSD) of 8-O-acetylharpagide in blood was lower than 9%, and the inter-day precision RSD was lower than 13%. The accuracy range was between 94.3% and 107.1%, average recovery was higher than 91.3%, and the matrix effect was between 100.8% and 110.8%. This analytical method was sensitive and fast with good selectivity and was successfully applied to perform pharmacokinetic studies of 8-O-acetylharpagide in mice. The bioavailability of 8-O-acetylharpagide was 10.8%, and the analysis of the primary pharmacokinetic parameters after oral and intravenous administration indicated that 8-O-acetylharpagide had a significant first pass effect after oral administration.
first rewind previous Strona / 3 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.