Aim To establish a LC-MS method for determining the concentration of nifedipine in human plasma and to evaluate the pharmacokinetic characteristics of nifedipine sustained-release tablets. Methods A XB-C18 (5 μm, 4....Aim To establish a LC-MS method for determining the concentration of nifedipine in human plasma and to evaluate the pharmacokinetic characteristics of nifedipine sustained-release tablets. Methods A XB-C18 (5 μm, 4.6 mm ×150 mm) column and a mobile phase of methanol: 0.01 mol·L^-1ammonium acetate (60:40, V/V) were used to separate nifedipine, the detections was accuracy under atmosperic pressure electronic spray ionization (AP-ESI) mode and ion mass spectrum (m/z) of 314.9 [M+H]^+ for nifedipine, and 320.8 [M+H]^+ for lorazepam (Internal Standard, IS). Results The linear range of nifedipine was 0.3 - 80 ng·mL^-1 ( r = 0.9997), and the limit of quantitation (LOQ) was 0.3 ng·mL^-1. The nifedipine pharmacokinetic parameters after a single dose of 20 mg nifedipine sustained-release tablets test (T) or reference (R) were as the followings, t1/2 (6.73 ± 2.00) h and (7.04 ± 2.18) h, Tmax (4.28 ± 0.70) h and (4.48 ± 0.70) h, Cmax(39.66 ± 10.58) ng·mL^-1 and (40.19 ± 10.97) ng·mL^-1, AUC0-36 (391.63 ± 108.55) ng·mL^-1·h and (387.57 ± 121.51) ng·mL^-1·h, and AUC0-∞ (408.28 ± 121.16) ng·mL^-1·h and (406.15 ± 133.13) ng·mL^-1·h. The relative bioavailability of nifedipine sustained-release tablets (test) was (103.02 ± 13.93) %. Conclusion LC-MS method for the determination of concentrations of nifedipine in human plasma was sensitive and accurate, and could be used in nifedipine bioavailability and pharmacokinetic studies.展开更多
A new HPLC MS method to determine loratadine in human plasma was established. The method involved extracting drug with organic solvent under basic conditions. The samples were seperated by ODS column and determined ...A new HPLC MS method to determine loratadine in human plasma was established. The method involved extracting drug with organic solvent under basic conditions. The samples were seperated by ODS column and determined by mass detector. The calibration curve of loratadine was linear within the range of 0.4~100 ng·mL -1 with r=0.9995 . The recovery of this method was within 95%~104%, within day and between day RSD were less than 12%. To study the pharmacokinetics and relative bioavailability of loratadine tablets, two formulations of loratadine tablets were given to 18 healthy male volunteers according to a randomized 2 way cross over design. The C max , AUC 0 t and T max values of the two formulations were 51.89±20.18 ng·mL -1 and 52.48±22.35 ng·mL -1 ; 140.75±88.42 ng·h·mL -1 and 147.24±92.33 ng·h·mL -1 ; 0.81±0.35 h and 0.81±0.27 h respectively. Results from statistic analysis showed that there were no significant difference between the C max , AUC 0-t and T max values of the two formulations. The relative bioavailability of tablets I with respect to tablets II was 97%±13% from the AUC 0 t measurement. Bioequivalance was observed between the two tablets.展开更多
Aim To establish a sensitive and specific liquid chromatography-mass spectrometry (HPLC-MS) method for measuring lovastatin level in human plasma and the relative bioavailability. Methods Lovastatin in the plasma was ...Aim To establish a sensitive and specific liquid chromatography-mass spectrometry (HPLC-MS) method for measuring lovastatin level in human plasma and the relative bioavailability. Methods Lovastatin in the plasma was extracted with acetoacetate. Simvastatin was added as internal standard (IS). Samples were separated on a C_ 18 column with a mobile phase consisting of methanol and 50 mmol·L~ -1 sodium acetate (88 ∶ 12). The flow rate was 1 mL·min~ -1 . Sample was detected using an electrospray ionization (ES...展开更多
Ahn To develop a high resolution HPLC method for the determination of ondansetron in human plasma and to study the pharmacokinetics of ondansetron in orally disintegrating tablets. Methods HPLC determination involved ...Ahn To develop a high resolution HPLC method for the determination of ondansetron in human plasma and to study the pharmacokinetics of ondansetron in orally disintegrating tablets. Methods HPLC determination involved liquid-liquid extraction, separation on a CN column and ultraviolet detection at 310 ran with granisetron as an internal standard. Pharmacokinetics and bioequivalence of ondansetron in orally disintegrating tablets by direct compression and conventional 8 mg tablets were evaluated and compared in 20 healthy human male volunteers after a single oral dose in a randomized cross-over study. Results The limit of quantification was 0.25 ng· mL^-1. The recovery was about 85 % or over for ondan setron and about 90% for internal standard. Linearity was good within the concentration range of 0.5 - 50 ng·mL^-1 with r^2 ranging from 0.997 1 to 0.999 9. Intra- and inter-assay coefficients of variation ranged from 1.78% to 2.38% and 3.88% -5.19%, respectively. Accuracies for spiked concentrations of 2.0, 10.0, and 30.0 ng·mL^-1 were 104.7% ±4.4%, 102.2% ± 1.1%, and99.51% ±2.34%, respectively. Pharmacokinetic parameters of AUCo-t, AUCo-∞ , Cmax, Tmax, and T1/2 were 230.2 ± 78.0 ng·h·L^-1 , 265.2± 101.5 ng·h·mL^-1, 35.67 ± 8.94 ng·mL^-l, 1.51 ±0.79 h, and 5.00± 1.41 h for orally disintegrating tablets, respectively. The analysis of variance did not show any significant difference between orally disintegrating tablets and conventional tablets, and 90% confidence intervals fell within the acceptable range for bioequivalence. Conclusion High resolution HPLC method has been set up and applied in pharmacokinetic evaluation of ondansetron in orally disintegrating tablets.展开更多
The enantioselective assay for S(+)- and R(-)-propafenone (PPF) in human urine that developed in this work involves extraction of propafenone from human urine and using S(+)-propafenone as internal standard, chiral de...The enantioselective assay for S(+)- and R(-)-propafenone (PPF) in human urine that developed in this work involves extraction of propafenone from human urine and using S(+)-propafenone as internal standard, chiral derivatization with 2,3,4,6-tetra-O-b-D-glucopranosyl isothiocyanate, and quantitation by an RP-HPLC system with UV detection (l=220 nm). A baseline separation of propafenone enantiomers was achieved on a 5-mm reverse phase ODS column, with a mixture of methanol:water:glacial acetic acid (25:12:0.02,v/v) as mobile phase. There was good linear relationship from 24.9 ng/ml to 1875.0 ng/ml for both of enantiomers. The regression equations of the standard curves based on CS-PPF (or CR-PPF ) versus ratio of AS-PPF/AS (or AR-PPF/AS ) were y=0.0032x-0.081, (r=0.999) for S-PPF and y=0.0033x+0.0039, (r=0.998) for R-PPF, respectively. The method抯 limit of detection was 12.5 ng/ml for both enantiomers, and the method抯 limit of quantitation was 28.20.52 ng/ml for S-PPF, 30.40.53 ng/ml for R-PPF (RSD<8%, n=5). The analytical method yielded average recovery of 98.9% and 100.4% for S-PPF and R-PPF, respectively. The relative standard deviation was no more than 6.11% and 6.22% for S-PPF and R-PPF, respectively. The method enabled study of metabolism of S(+)- and R(-)-propafenone in human urine. The results from 7 volunteers administered 150 mg racemic propafenone indicated that propafenone enantiomers undergo stereoselective metabolism and that in the human body, S(+)-propafenone is metabolized more extensively than R(-)- propafenone.展开更多
The purpose of this research was to study the pharmacokinetics and the bioavailability of recombinant human parathyroid hormone [rhPTH (1-34)] in Rhesus monkeys after single and multiple subcutaneous administration....The purpose of this research was to study the pharmacokinetics and the bioavailability of recombinant human parathyroid hormone [rhPTH (1-34)] in Rhesus monkeys after single and multiple subcutaneous administration. An immunoradiometric assay (IRMA) was used to determine the plasma drug concentration of rhFFH (1-34) after giving single dose of 10, 20 and 40 ug/kg and daily dose of 40 ug/kg for 7 d by subcutaneous administration, and intravenous injection of 20 ug/kg in Rhesus monkeys. The pharmacokinetic parameters were calculated by noncompartmental analysis. The drug plasma level quantitation range was from 0.027 to 2.22 ng/mL. The intra- and inter-assay precision (CV) of analysis were less than 15%, and the average recovery was about 93.0% ± 8.6% - 116.5% ± 14.0%. After subcutaneous administration of rhPTH(1-34) at dose of 10, 20 and 40 ug/kg, the average Tmax was 0.67, 0.5 and 0.83 h, Cmax were 1.85 ± 0.05, 3.23 ± 0.25 and 7.15 ± 1.19 ng/mL, the AUC(0-∞) were 3.4 ± 0.6, 10.7 ± 1.3 and 12.6 ± 1.5 ng/h/mL, and terminal-phase elimination T1/2 were 0.72 ± 0.10, 1.15 ± 0.10 and 1.03 ± 0.06 h, respectively. The absolute bioavailability of rhPTH (1-34) was 46.96% after subcutaneous administration of 20 ug/kg. There was no evidence of accumulation during systemic exposure of rhPTH (1-34) upon multiple dosing in Rhesus monkeys. The IRMA assay method provide reasonable sensitivity and specificity for the pharrnacokinetic study of rhPTH (1-34) after subcutaneous or intravenous administration in Rhesus monkeys. The pharmacokinetic characteristic of rhPTH (1-34) in monkeys shows linear relationship with the dose administered subcutaneously.展开更多
AimTo characterize the pharmacokinetics of 2 -amino-6-cyclopropylamino-9-(2,3-dideoxy-β-D-glyceropent-2-enofuran osyl) purine (Cyclo-D4G) following intravenous administration and oral administ ration to rats. Methods...AimTo characterize the pharmacokinetics of 2 -amino-6-cyclopropylamino-9-(2,3-dideoxy-β-D-glyceropent-2-enofuran osyl) purine (Cyclo-D4G) following intravenous administration and oral administ ration to rats. MethodsThe concentrations of Cyclo-D4G in rat (Sprague-Dawley male rats) plasma and urine were analyzed by high performance liquid chromatography (HPLC). ResultsFollowing intravenous adm inistration to rats, concentrations of Cyclo-D4G in plasma declined with a term inal phase half-life of 0 78±0 14 h (±s). Total clearance was 0 90±0 21 L·h -1 ·kg -1 . Renal excretion of unchanged Cyclo-D4G accounted for approximately 20% of total clearance. Steady state volume of distr ibution was 0 91±0 07 L·kg -1 . After oral administration to rats, conce ntrations of Cyclo-D4G in plasma declined with a terminal phase half-life of 0 83±0 13 h (±s). Total clearance was 3 81±2 03 L·h -1 ·kg -1 . Renal excretion of unchanged Cyclo-D4G accounted for approximat ely 9% of total clearance. Oral bioavailability of Cyclo-D4G in rat was 26 9%. ConclusionThe favorable pharmacokinetic profiles and lower to xicity provide support for further development of Cyclo-D4G clinical trials.展开更多
P-glycoprotein(P-gp)is an important transmembrane ATP-binding cassette(ABC)drug efflux transporter expressed in various human tissues such as the intestines,liver,kidneys,and bloodbrain barrier.It limits the intracell...P-glycoprotein(P-gp)is an important transmembrane ATP-binding cassette(ABC)drug efflux transporter expressed in various human tissues such as the intestines,liver,kidneys,and bloodbrain barrier.It limits the intracellular concentration of xenobiotics by pumping them out of the cells,affecting drug pharmacokinetics and therapeutic effects.With its broad substrate specificity,it has the potential to remove a wide range of drugs from Chinese materia medica(CMM),including conventional medicines and active compounds.Increasing evidence has confirmed the superior therapeutic effectiveness of CMM in treating a wide range of diseases worldwide,as well as in conjunction with western drugs.As a result,herbal medicine-drug compounds have prompted widespread concern,with the majority of these interactions involving transporters such as P-gp.This review systematically summarizes the inhibition or induction of P-gp expression/function by active CMM compounds and the underlying regulatory mechanisms.It will aid in improving understanding of the synergistic or inhibiting effects associated with transporter P-gp as well as rational safety concerns for using CMM,particularly in combination with drugs.展开更多
Alantolactone, as the principal constituent oflnula Helenium L, has been shown various pharmacologic activities, such as anti-inflammatory and deworming. In the present study, we developed a high performance liquid ch...Alantolactone, as the principal constituent oflnula Helenium L, has been shown various pharmacologic activities, such as anti-inflammatory and deworming. In the present study, we developed a high performance liquid chromatography (HPLC) method for the determination of alantolactone in rat plasma, and pharmacokinetics of alantolactone was investigated after intravenous and oral administrations to Wistar rats. Separation was achieved on C18 column (4.6 mm×250 mm, 5.0 μm) using a mobile phase consisting of methanol-water (70:30, v/v) at a flow rate of 1.0 mL/min. The wavelength of the ultraviolet detector was set at 239 nm. The excellent linearity was found over a concentration range of 0.08-10 μg/mL (R2 = 0.9998). The intra- and inter-day precisions were good, and the RSD was lower than 2.27%. The mean absolute recovery of alantolactone in plasma ranged from 88.09% to 95.57%. After intravenous administration, alantolactone showed rapid systemic clearance (CL (0.11±0.014) L/h/kg) and small volume of distribution (Vd (0.71±0.14) L/kg). The biological half life (t1/2) was 56.24 min. After oral administration, alantolactone showed rapid oral absorption in rats, with a short Tmax of (45.02±0.88) and (45.13±0.39) min for 14 and 28 mg/kg, respectively. The bioavailability of alantolactone in rats was 50.88%, indicating that alantolactone was orally available.展开更多
We performed a systematic review to evaluate pharmacokinetics changes of drugs when concomitantly used with voriconazole, including randomized controlled trials(RCTs), randomized cross-over trials, self-controlled b...We performed a systematic review to evaluate pharmacokinetics changes of drugs when concomitantly used with voriconazole, including randomized controlled trials(RCTs), randomized cross-over trials, self-controlled before-and-after studies, cohort studies and case reports. Literature databases, including Medline, Embase, Cochrane library, were searched to identify eligible studies(until Jan, 2016). A modified risk of bias tool specially developed in this research was used to evaluate the quality of pharmacokinetic randomized crossover trials and self-controlled before-and-after studies. Cochrane risk of bias tool provided by Cochrane Library and Cochrane Reviewer's handbook was used to evaluate the quality of RCTs and non-randomized controlled studies. Pharmacokinetic parameters, such as area under curve(AUC), Cmin, and Cmax before and after using voriconalzole were collected. Meta-analysis was conducted to synthesize results if possible. Among 41 studies included in our search, 17 were randomized crossover trials, 3 were RCTs, 13 were self-controlled before-and-after study(SBAs), 1 was cohort studies and 7 were case reports. A total of 12 classes of drugs were involved, including opiates, non-steroidal anti-inflammatory drugs(NSAIDs), psychopathic drugs, anti-HIV drugs, immunosuppressors, oral contraceptive, digoxin, warfarin, oral hypoglycemic agents, antihypertensive agents, lipid regulating agents and cytotoxic agents. According to our results, the impacts of voriconazole on tilidine, buprenorphine, etoricoxib, meloxicam, venlafaxine, midazolam, zolpidem, etravirine and sirolimus were different from the package insert. Our systematic review provided comprehensive data on the pharmacokinetics changes of drugs when used in combination with voriconazole.展开更多
In the present study, a simple, rapid, and sensitive liquid chromatography-tandem mass spectrometric method for the determination of axitinib in nude mouse plasma was developed, validated, and applied to a pharmacokin...In the present study, a simple, rapid, and sensitive liquid chromatography-tandem mass spectrometric method for the determination of axitinib in nude mouse plasma was developed, validated, and applied to a pharmacokinetic study. Plasma samples were pre-treated by protein precipitation with acetonitrile spiked with erlotinib as an internal standard. The chromatographic separation was accomplished by using a reversed phase C18 column (50 mm×2 mm, 5 μm) with a simple mobile phase system composed of methanol and water (60:40, v/v) at an isocratic flow rate of 0.4 mL/min. The analyte was detected by a triple-quadrupole tandem mass spectrometer via electrospray ionization and multiple reaction monitoring was employed to select both axitinib and erlotinib in the positive ion mode. The calibration curves were linear (r〉0.99) ranging from 1 to 1000 ng/mL, and the lowest level of this range was the lower limit of quantification. The intra- and inter-day precision were 7.7%-12.0%, and the accuracies ranged from 88.6% to 110.4%. This method was successfully applied to a preclinical pharmacokinetic study on female nu/nu nude mice administrated with a single oral dose of axitinib at 120 mg/kg, and the pharmacokinetics was characterized by a one-compartment model with first-order absorption.展开更多
In the current study, we established and validated a simple and sensitive liquid chromatography-tandem mass spectrometric method for the determination of 21-hydroxy deflazacort in nude mice plasma, and such a method w...In the current study, we established and validated a simple and sensitive liquid chromatography-tandem mass spectrometric method for the determination of 21-hydroxy deflazacort in nude mice plasma, and such a method was applied to a pharmacokinetic study. Using betamethasone as the internal standard, the plasma samples were pre-treated by precipitation with acetonitrile and then analyzed on a reversed-phase C18 column (50 mm×2 mm, 5 μm) with a mobile phase consisting of acetonitrile and 4.0 mM ammonium formate (pH was adjusted to 3.5 with formic acid (40:60, v/v)). The analyte was detected by a triple quadrupole tandem mass spectrometer using electrospray, and multiple reaction monitoring was employed to select 21-hydroxy deflazacort at m/z 400.2/124.0 and betamethasone at m/z 393.3/147.0 in the positive ion mode. The calibration curves were linear (r〉0.99) over the range of 0.5~,00 ng/mL. The intra- and inter-day precisions and accuracies were 4.5%-10.1% and -1.7%-10.7% respectively. This method was successfully applied to a preclinical administered with a single oral dose of 4 mg/kg deflazacort, and its pharmacokinetic study of deflazacort on female nude mice pharmacokinetics was characterized by a two-compartment model with first-order absorption.展开更多
Total paeony glycoside(TPG) is obtained from Radix Paeoniae Rubra with a variety of bioactivities. However, the low solubility and bioavailability limit its application. The present study aimed to develop TPG nanocr...Total paeony glycoside(TPG) is obtained from Radix Paeoniae Rubra with a variety of bioactivities. However, the low solubility and bioavailability limit its application. The present study aimed to develop TPG nanocrystals to increase the dissolution and then improve the oral bioavailability. TPG nanocrystals were prepared via precipitation and high-pressure homogenization method. The physical-chemical properties of the optimal TPG nanocrystals in terms of particle size, zeta potential, morphology and crystallinity were evaluated. The results showed that TPG nanocrystals had a mean particle size of(210.2±2.5) nm, a polydispersity index of 0.191±0.033 and a zeta potential of(–22.4±1.2) mV. The result of differential scanning calorimetry showed that the nanocrystals were still in crystalline state after the preparation procedure. Transmission electron microscopy(TEM) results showed that the nanosuspension was in spherical shape. The pharmacokinetics of TPG nanocrystals for rats was investigated by liquid chromatography-tandem mass spectroscopy(LC-MS/MS). Compared with the TPG coarse suspension, TPG nanocrystals exhibited significant increase in AUC0–∞(approximately 1.85-fold). Taken together, TPG nanocrystals could be used as a promising drug delivery system due to the enhanced oral bioavailability of TPG.展开更多
文摘Aim To establish a LC-MS method for determining the concentration of nifedipine in human plasma and to evaluate the pharmacokinetic characteristics of nifedipine sustained-release tablets. Methods A XB-C18 (5 μm, 4.6 mm ×150 mm) column and a mobile phase of methanol: 0.01 mol·L^-1ammonium acetate (60:40, V/V) were used to separate nifedipine, the detections was accuracy under atmosperic pressure electronic spray ionization (AP-ESI) mode and ion mass spectrum (m/z) of 314.9 [M+H]^+ for nifedipine, and 320.8 [M+H]^+ for lorazepam (Internal Standard, IS). Results The linear range of nifedipine was 0.3 - 80 ng·mL^-1 ( r = 0.9997), and the limit of quantitation (LOQ) was 0.3 ng·mL^-1. The nifedipine pharmacokinetic parameters after a single dose of 20 mg nifedipine sustained-release tablets test (T) or reference (R) were as the followings, t1/2 (6.73 ± 2.00) h and (7.04 ± 2.18) h, Tmax (4.28 ± 0.70) h and (4.48 ± 0.70) h, Cmax(39.66 ± 10.58) ng·mL^-1 and (40.19 ± 10.97) ng·mL^-1, AUC0-36 (391.63 ± 108.55) ng·mL^-1·h and (387.57 ± 121.51) ng·mL^-1·h, and AUC0-∞ (408.28 ± 121.16) ng·mL^-1·h and (406.15 ± 133.13) ng·mL^-1·h. The relative bioavailability of nifedipine sustained-release tablets (test) was (103.02 ± 13.93) %. Conclusion LC-MS method for the determination of concentrations of nifedipine in human plasma was sensitive and accurate, and could be used in nifedipine bioavailability and pharmacokinetic studies.
文摘A new HPLC MS method to determine loratadine in human plasma was established. The method involved extracting drug with organic solvent under basic conditions. The samples were seperated by ODS column and determined by mass detector. The calibration curve of loratadine was linear within the range of 0.4~100 ng·mL -1 with r=0.9995 . The recovery of this method was within 95%~104%, within day and between day RSD were less than 12%. To study the pharmacokinetics and relative bioavailability of loratadine tablets, two formulations of loratadine tablets were given to 18 healthy male volunteers according to a randomized 2 way cross over design. The C max , AUC 0 t and T max values of the two formulations were 51.89±20.18 ng·mL -1 and 52.48±22.35 ng·mL -1 ; 140.75±88.42 ng·h·mL -1 and 147.24±92.33 ng·h·mL -1 ; 0.81±0.35 h and 0.81±0.27 h respectively. Results from statistic analysis showed that there were no significant difference between the C max , AUC 0-t and T max values of the two formulations. The relative bioavailability of tablets I with respect to tablets II was 97%±13% from the AUC 0 t measurement. Bioequivalance was observed between the two tablets.
文摘Aim To establish a sensitive and specific liquid chromatography-mass spectrometry (HPLC-MS) method for measuring lovastatin level in human plasma and the relative bioavailability. Methods Lovastatin in the plasma was extracted with acetoacetate. Simvastatin was added as internal standard (IS). Samples were separated on a C_ 18 column with a mobile phase consisting of methanol and 50 mmol·L~ -1 sodium acetate (88 ∶ 12). The flow rate was 1 mL·min~ -1 . Sample was detected using an electrospray ionization (ES...
文摘Ahn To develop a high resolution HPLC method for the determination of ondansetron in human plasma and to study the pharmacokinetics of ondansetron in orally disintegrating tablets. Methods HPLC determination involved liquid-liquid extraction, separation on a CN column and ultraviolet detection at 310 ran with granisetron as an internal standard. Pharmacokinetics and bioequivalence of ondansetron in orally disintegrating tablets by direct compression and conventional 8 mg tablets were evaluated and compared in 20 healthy human male volunteers after a single oral dose in a randomized cross-over study. Results The limit of quantification was 0.25 ng· mL^-1. The recovery was about 85 % or over for ondan setron and about 90% for internal standard. Linearity was good within the concentration range of 0.5 - 50 ng·mL^-1 with r^2 ranging from 0.997 1 to 0.999 9. Intra- and inter-assay coefficients of variation ranged from 1.78% to 2.38% and 3.88% -5.19%, respectively. Accuracies for spiked concentrations of 2.0, 10.0, and 30.0 ng·mL^-1 were 104.7% ±4.4%, 102.2% ± 1.1%, and99.51% ±2.34%, respectively. Pharmacokinetic parameters of AUCo-t, AUCo-∞ , Cmax, Tmax, and T1/2 were 230.2 ± 78.0 ng·h·L^-1 , 265.2± 101.5 ng·h·mL^-1, 35.67 ± 8.94 ng·mL^-l, 1.51 ±0.79 h, and 5.00± 1.41 h for orally disintegrating tablets, respectively. The analysis of variance did not show any significant difference between orally disintegrating tablets and conventional tablets, and 90% confidence intervals fell within the acceptable range for bioequivalence. Conclusion High resolution HPLC method has been set up and applied in pharmacokinetic evaluation of ondansetron in orally disintegrating tablets.
基金Project supported by the National Natural Science Foundation of China (No. 30225047) and by SRF for ROCS+2 种基金 SEM and Zhejiang Provincial Natural Science Foundation (No. RC97016) China
文摘The enantioselective assay for S(+)- and R(-)-propafenone (PPF) in human urine that developed in this work involves extraction of propafenone from human urine and using S(+)-propafenone as internal standard, chiral derivatization with 2,3,4,6-tetra-O-b-D-glucopranosyl isothiocyanate, and quantitation by an RP-HPLC system with UV detection (l=220 nm). A baseline separation of propafenone enantiomers was achieved on a 5-mm reverse phase ODS column, with a mixture of methanol:water:glacial acetic acid (25:12:0.02,v/v) as mobile phase. There was good linear relationship from 24.9 ng/ml to 1875.0 ng/ml for both of enantiomers. The regression equations of the standard curves based on CS-PPF (or CR-PPF ) versus ratio of AS-PPF/AS (or AR-PPF/AS ) were y=0.0032x-0.081, (r=0.999) for S-PPF and y=0.0033x+0.0039, (r=0.998) for R-PPF, respectively. The method抯 limit of detection was 12.5 ng/ml for both enantiomers, and the method抯 limit of quantitation was 28.20.52 ng/ml for S-PPF, 30.40.53 ng/ml for R-PPF (RSD<8%, n=5). The analytical method yielded average recovery of 98.9% and 100.4% for S-PPF and R-PPF, respectively. The relative standard deviation was no more than 6.11% and 6.22% for S-PPF and R-PPF, respectively. The method enabled study of metabolism of S(+)- and R(-)-propafenone in human urine. The results from 7 volunteers administered 150 mg racemic propafenone indicated that propafenone enantiomers undergo stereoselective metabolism and that in the human body, S(+)-propafenone is metabolized more extensively than R(-)- propafenone.
文摘The purpose of this research was to study the pharmacokinetics and the bioavailability of recombinant human parathyroid hormone [rhPTH (1-34)] in Rhesus monkeys after single and multiple subcutaneous administration. An immunoradiometric assay (IRMA) was used to determine the plasma drug concentration of rhFFH (1-34) after giving single dose of 10, 20 and 40 ug/kg and daily dose of 40 ug/kg for 7 d by subcutaneous administration, and intravenous injection of 20 ug/kg in Rhesus monkeys. The pharmacokinetic parameters were calculated by noncompartmental analysis. The drug plasma level quantitation range was from 0.027 to 2.22 ng/mL. The intra- and inter-assay precision (CV) of analysis were less than 15%, and the average recovery was about 93.0% ± 8.6% - 116.5% ± 14.0%. After subcutaneous administration of rhPTH(1-34) at dose of 10, 20 and 40 ug/kg, the average Tmax was 0.67, 0.5 and 0.83 h, Cmax were 1.85 ± 0.05, 3.23 ± 0.25 and 7.15 ± 1.19 ng/mL, the AUC(0-∞) were 3.4 ± 0.6, 10.7 ± 1.3 and 12.6 ± 1.5 ng/h/mL, and terminal-phase elimination T1/2 were 0.72 ± 0.10, 1.15 ± 0.10 and 1.03 ± 0.06 h, respectively. The absolute bioavailability of rhPTH (1-34) was 46.96% after subcutaneous administration of 20 ug/kg. There was no evidence of accumulation during systemic exposure of rhPTH (1-34) upon multiple dosing in Rhesus monkeys. The IRMA assay method provide reasonable sensitivity and specificity for the pharrnacokinetic study of rhPTH (1-34) after subcutaneous or intravenous administration in Rhesus monkeys. The pharmacokinetic characteristic of rhPTH (1-34) in monkeys shows linear relationship with the dose administered subcutaneously.
文摘AimTo characterize the pharmacokinetics of 2 -amino-6-cyclopropylamino-9-(2,3-dideoxy-β-D-glyceropent-2-enofuran osyl) purine (Cyclo-D4G) following intravenous administration and oral administ ration to rats. MethodsThe concentrations of Cyclo-D4G in rat (Sprague-Dawley male rats) plasma and urine were analyzed by high performance liquid chromatography (HPLC). ResultsFollowing intravenous adm inistration to rats, concentrations of Cyclo-D4G in plasma declined with a term inal phase half-life of 0 78±0 14 h (±s). Total clearance was 0 90±0 21 L·h -1 ·kg -1 . Renal excretion of unchanged Cyclo-D4G accounted for approximately 20% of total clearance. Steady state volume of distr ibution was 0 91±0 07 L·kg -1 . After oral administration to rats, conce ntrations of Cyclo-D4G in plasma declined with a terminal phase half-life of 0 83±0 13 h (±s). Total clearance was 3 81±2 03 L·h -1 ·kg -1 . Renal excretion of unchanged Cyclo-D4G accounted for approximat ely 9% of total clearance. Oral bioavailability of Cyclo-D4G in rat was 26 9%. ConclusionThe favorable pharmacokinetic profiles and lower to xicity provide support for further development of Cyclo-D4G clinical trials.
基金the Macao Science and Technology Development Fund(No.0067/2019/A2 and No.0075/2019/AMJ)from the Macao Special Administrative Region。
文摘P-glycoprotein(P-gp)is an important transmembrane ATP-binding cassette(ABC)drug efflux transporter expressed in various human tissues such as the intestines,liver,kidneys,and bloodbrain barrier.It limits the intracellular concentration of xenobiotics by pumping them out of the cells,affecting drug pharmacokinetics and therapeutic effects.With its broad substrate specificity,it has the potential to remove a wide range of drugs from Chinese materia medica(CMM),including conventional medicines and active compounds.Increasing evidence has confirmed the superior therapeutic effectiveness of CMM in treating a wide range of diseases worldwide,as well as in conjunction with western drugs.As a result,herbal medicine-drug compounds have prompted widespread concern,with the majority of these interactions involving transporters such as P-gp.This review systematically summarizes the inhibition or induction of P-gp expression/function by active CMM compounds and the underlying regulatory mechanisms.It will aid in improving understanding of the synergistic or inhibiting effects associated with transporter P-gp as well as rational safety concerns for using CMM,particularly in combination with drugs.
基金The National Natural Science fund of China(Grant No.31360379)the open fund of the Key Laboratory of the New Animal Drug Project of Gansu Provincethe Key Laboratory of Veterinary Pharmaceutical Development of the Ministry of Agriculture(Grant No.2014)
文摘Alantolactone, as the principal constituent oflnula Helenium L, has been shown various pharmacologic activities, such as anti-inflammatory and deworming. In the present study, we developed a high performance liquid chromatography (HPLC) method for the determination of alantolactone in rat plasma, and pharmacokinetics of alantolactone was investigated after intravenous and oral administrations to Wistar rats. Separation was achieved on C18 column (4.6 mm×250 mm, 5.0 μm) using a mobile phase consisting of methanol-water (70:30, v/v) at a flow rate of 1.0 mL/min. The wavelength of the ultraviolet detector was set at 239 nm. The excellent linearity was found over a concentration range of 0.08-10 μg/mL (R2 = 0.9998). The intra- and inter-day precisions were good, and the RSD was lower than 2.27%. The mean absolute recovery of alantolactone in plasma ranged from 88.09% to 95.57%. After intravenous administration, alantolactone showed rapid systemic clearance (CL (0.11±0.014) L/h/kg) and small volume of distribution (Vd (0.71±0.14) L/kg). The biological half life (t1/2) was 56.24 min. After oral administration, alantolactone showed rapid oral absorption in rats, with a short Tmax of (45.02±0.88) and (45.13±0.39) min for 14 and 28 mg/kg, respectively. The bioavailability of alantolactone in rats was 50.88%, indicating that alantolactone was orally available.
文摘We performed a systematic review to evaluate pharmacokinetics changes of drugs when concomitantly used with voriconazole, including randomized controlled trials(RCTs), randomized cross-over trials, self-controlled before-and-after studies, cohort studies and case reports. Literature databases, including Medline, Embase, Cochrane library, were searched to identify eligible studies(until Jan, 2016). A modified risk of bias tool specially developed in this research was used to evaluate the quality of pharmacokinetic randomized crossover trials and self-controlled before-and-after studies. Cochrane risk of bias tool provided by Cochrane Library and Cochrane Reviewer's handbook was used to evaluate the quality of RCTs and non-randomized controlled studies. Pharmacokinetic parameters, such as area under curve(AUC), Cmin, and Cmax before and after using voriconalzole were collected. Meta-analysis was conducted to synthesize results if possible. Among 41 studies included in our search, 17 were randomized crossover trials, 3 were RCTs, 13 were self-controlled before-and-after study(SBAs), 1 was cohort studies and 7 were case reports. A total of 12 classes of drugs were involved, including opiates, non-steroidal anti-inflammatory drugs(NSAIDs), psychopathic drugs, anti-HIV drugs, immunosuppressors, oral contraceptive, digoxin, warfarin, oral hypoglycemic agents, antihypertensive agents, lipid regulating agents and cytotoxic agents. According to our results, the impacts of voriconazole on tilidine, buprenorphine, etoricoxib, meloxicam, venlafaxine, midazolam, zolpidem, etravirine and sirolimus were different from the package insert. Our systematic review provided comprehensive data on the pharmacokinetics changes of drugs when used in combination with voriconazole.
基金National Natural Science Foundation of China(NSFC,Grant No.81473277)
文摘In the present study, a simple, rapid, and sensitive liquid chromatography-tandem mass spectrometric method for the determination of axitinib in nude mouse plasma was developed, validated, and applied to a pharmacokinetic study. Plasma samples were pre-treated by protein precipitation with acetonitrile spiked with erlotinib as an internal standard. The chromatographic separation was accomplished by using a reversed phase C18 column (50 mm×2 mm, 5 μm) with a simple mobile phase system composed of methanol and water (60:40, v/v) at an isocratic flow rate of 0.4 mL/min. The analyte was detected by a triple-quadrupole tandem mass spectrometer via electrospray ionization and multiple reaction monitoring was employed to select both axitinib and erlotinib in the positive ion mode. The calibration curves were linear (r〉0.99) ranging from 1 to 1000 ng/mL, and the lowest level of this range was the lower limit of quantification. The intra- and inter-day precision were 7.7%-12.0%, and the accuracies ranged from 88.6% to 110.4%. This method was successfully applied to a preclinical pharmacokinetic study on female nu/nu nude mice administrated with a single oral dose of axitinib at 120 mg/kg, and the pharmacokinetics was characterized by a one-compartment model with first-order absorption.
基金National Natural Science Foundation of China(NSFC,Grant No.81673500)
文摘In the current study, we established and validated a simple and sensitive liquid chromatography-tandem mass spectrometric method for the determination of 21-hydroxy deflazacort in nude mice plasma, and such a method was applied to a pharmacokinetic study. Using betamethasone as the internal standard, the plasma samples were pre-treated by precipitation with acetonitrile and then analyzed on a reversed-phase C18 column (50 mm×2 mm, 5 μm) with a mobile phase consisting of acetonitrile and 4.0 mM ammonium formate (pH was adjusted to 3.5 with formic acid (40:60, v/v)). The analyte was detected by a triple quadrupole tandem mass spectrometer using electrospray, and multiple reaction monitoring was employed to select 21-hydroxy deflazacort at m/z 400.2/124.0 and betamethasone at m/z 393.3/147.0 in the positive ion mode. The calibration curves were linear (r〉0.99) over the range of 0.5~,00 ng/mL. The intra- and inter-day precisions and accuracies were 4.5%-10.1% and -1.7%-10.7% respectively. This method was successfully applied to a preclinical administered with a single oral dose of 4 mg/kg deflazacort, and its pharmacokinetic study of deflazacort on female nude mice pharmacokinetics was characterized by a two-compartment model with first-order absorption.
基金Innovation Team Project(Grant No.LT2015011)from the Education Department of Liaoning ProvinceImportant Sci entific and Technical Achievements Transformation Project(Gr ant No.Z17-5-078)+1 种基金Applied Basic Research Project(Grant No.F16205144)of Science and Technology Bureau of Shenyangthe Liaoning Provincial Education Department Project of China(Grant No.L2015192)
文摘Total paeony glycoside(TPG) is obtained from Radix Paeoniae Rubra with a variety of bioactivities. However, the low solubility and bioavailability limit its application. The present study aimed to develop TPG nanocrystals to increase the dissolution and then improve the oral bioavailability. TPG nanocrystals were prepared via precipitation and high-pressure homogenization method. The physical-chemical properties of the optimal TPG nanocrystals in terms of particle size, zeta potential, morphology and crystallinity were evaluated. The results showed that TPG nanocrystals had a mean particle size of(210.2±2.5) nm, a polydispersity index of 0.191±0.033 and a zeta potential of(–22.4±1.2) mV. The result of differential scanning calorimetry showed that the nanocrystals were still in crystalline state after the preparation procedure. Transmission electron microscopy(TEM) results showed that the nanosuspension was in spherical shape. The pharmacokinetics of TPG nanocrystals for rats was investigated by liquid chromatography-tandem mass spectroscopy(LC-MS/MS). Compared with the TPG coarse suspension, TPG nanocrystals exhibited significant increase in AUC0–∞(approximately 1.85-fold). Taken together, TPG nanocrystals could be used as a promising drug delivery system due to the enhanced oral bioavailability of TPG.