Peptides play multiple functions in cellular processes and are considered an attractive paradigm for the development of novel drugs and therapeutic approaches. However, the complexity of their pharmacokinetics/pharmac...Peptides play multiple functions in cellular processes and are considered an attractive paradigm for the development of novel drugs and therapeutic approaches. However, the complexity of their pharmacokinetics/pharmacodynamics and physicochemical properties presents challenges in their development. Currently, there is no single analytical method that fully meets the requirements for studying peptide drug pharmacokinetics. Interdisciplinary teams and multiple technical platforms are required to address these challenges. This article explores the pharmacokinetics, bioanalytical methods, challenges, and strategies in the development of peptide drugs. As our understanding of peptide drug pharmacokinetics and bioanalytical characteristics deepens, it will facilitate their development and provide scientific evidence for rational clinical use.展开更多
A new method using high-performance liquid chromatography coupled with ultra violet detection(HPLC–UV)was developed and validated for the simultaneous quantification of atazanavir,dolutegravir,darunavir,efavirenz,etr...A new method using high-performance liquid chromatography coupled with ultra violet detection(HPLC–UV)was developed and validated for the simultaneous quantification of atazanavir,dolutegravir,darunavir,efavirenz,etravirine lopinavir,raltegravir,rilpivirine and tipranavir in human plasma.For the first time we reported here the development and validation of an HPLC–UV assay to quantify the frequently administered 9antiretroviral compounds including dolutegravir and rilpivirine.A simple solid phase extraction procedure was applied to 500 μL aliquots of plasma.The chromatographic separation of the drugs and internal standard(quinoxaline) was achieved with a gradient of acetonitrile and sodium acetate buffer on a C_(18) reverse-phase analytical column with a 25 min analytical run time.Calibration curves were optimised according to the therapeutic range of drug concentrations in patients,and the coefficient of determination(r^2) was higher than0.99 for all analytes.Mean intraday and interday precisions(RSD) for all compounds were less than 15.0%,and the mean accuracy(% deviation from nominal concentration) was also found to be less than 15.0%.Extraction recovery range was between 80% and 120% for all drugs analysed.The solid phase extraction and HPLC–UV method enable a specific,sensitive,and reliable simultaneous determination of nine antiretroviral agents in plasma.Good extraction efficiency and low limit of HPLC–UV quantification make this method suitable for use in clinical trials and therapeutic drug monitoring.展开更多
Abstract: A Selective new reagent Wazo-1 was prepared. This paper studied the properties of its fluorescence and UV- Spectrum. A new fluorescence method for the determination of clacium is developed. Wazo-1 reacts wit...Abstract: A Selective new reagent Wazo-1 was prepared. This paper studied the properties of its fluorescence and UV- Spectrum. A new fluorescence method for the determination of clacium is developed. Wazo-1 reacts with calcium. forms calcium complex(Ex=297nm; Em=370nm). The interference of Mg(Ⅱ)has been studied. The reagent has better selectivity to Ca(Ⅱ) in the presence of large amount of Mg(Ⅱ). Fluorescence method has-been used for determination of microamounts of calcium in serum with new reagent Wazo-1.The results obtained are favourable.展开更多
A liquid chromatography tandem mass spectrometry (LC-MS/MS) based method was developed for the simultaneous monitoring plasma levels of Sitagliptin (STG) and Pioglitazone (PIO) for applicability to pharmacokinetic stu...A liquid chromatography tandem mass spectrometry (LC-MS/MS) based method was developed for the simultaneous monitoring plasma levels of Sitagliptin (STG) and Pioglitazone (PIO) for applicability to pharmacokinetic studies. The method was based on HPLC separation on the reversed phase Phenomenex Synergy C18 column (30 mm length, 4.6 mm internal diameter, and 4.0 μm particle size) at a temperature of 40?C using a binary gradient mobile phase consisting of methanol and 2 mM ammonium acetate buffer pH adjusted to 4.5 with acetic acid, at a flow rate of 1 mL?min?1. Tolbutamide was used as an internal standard. Detection of analytes was achieved with LC-MS/MS system in Multiple Reaction Monitoring (MRM) mode. The method was validated over concentration range of 10.98 - 2091.77 ng?mL?1 for SIT and 8.25 - 1571.63 ng?mL?1 for PIO and lower limit of quantification was 10.98 ng?mL?1 and 8.25 ng?mL?1 for STG and PIO respectively. Recoveries from spiked controls were within acceptance criteria for all the analytes and internal standard at all QC levels. Within batch and between batch accuracy for STG was found within 96.9% - 100.3% and for PIO was found within 100.0% - 104.3%. Within batch and between batch precision for STG was less than 3.1% CV (coefficient of variation) and for PIO was less than 5.3% CV at all concentrations levels. This method was successfully applied to monitor pharmacokinetics profile of both STG and PIO on simultaneous oral administration to rats. This method can be applicable for pharmacokinetic drug-drug interaction studies.展开更多
Repaglinide is type 2 short acting anti-diabetic drug which is primarily metabolized by CYP2C8 and CYP3A4 and is also a substrate of influx transporter OATP1B1. HIV drugs are potent inhibitors of CYP3A4 and OATP trans...Repaglinide is type 2 short acting anti-diabetic drug which is primarily metabolized by CYP2C8 and CYP3A4 and is also a substrate of influx transporter OATP1B1. HIV drugs are potent inhibitors of CYP3A4 and OATP transporters. Several drug-drug interactions (DDIs) were noticed when protease inhibitors (PIs) coadministered with drugs metabolized by CYP3A4. The PIs are also potent mechanism based inhibitors, out which ritonavir is most potent. In the current study we evaluated in vitro (mouse and human liver microsomes) and in vivo DDIs of repaglinide with anti-HIV drugs. Out of the following tested drugs (Amprenavir, Indinavir, Nelfinavir, Ritonavir, Saquinavir, Delavirdine, Maraviroc, Efavirenz, Nevirapine and Ketoconazole) Amprenavir (APV), Ritonavir (RTV) and Ketoconazole (KTZ) showed inhibition of OH-repaglinide formation in human and mouse liver microsomes. The positive reversible inhibitions were further tested for irreversible inhibitions where we didn’t observe any irreversible inhibitions. In vitro inhibitions were further evaluated in the in vivo pharmacokinetics (mouse) where repaglinide pharmacokinetics was altered by RTV and KTZ. The DDIs in both studies were very strong;the dose of repaglinide is reduced to 20 fold. In conclusion, there could be possible DDIs when RTV dosed with repaglinide;we have also demonstrated that mouse could be useful preclinical tool when used in conjunction with in vitro screening models for DDIs.展开更多
<span style="font-family:""><span style="font-family:Verdana;">Infection with </span><i><span style="font-family:Verdana;">Toxoplasma gondii</span>...<span style="font-family:""><span style="font-family:Verdana;">Infection with </span><i><span style="font-family:Verdana;">Toxoplasma gondii</span></i><span style="font-family:Verdana;">, is one of the most widespread zoonoses in the world. Congenital Toxoplasmosis (CT) is particularly risky due to its fetal </span><span style="font-family:Verdana;">complications. Sulfadiazine (SDZ) and Pyrimethamine (PYR) are usually </span><span style="font-family:Verdana;">used </span><span style="font-family:Verdana;">for CT treatment in Argentina, to prevent morbidity. Due to the lack of </span><span style="font-family:Verdana;">commercial pediatric formulations, these must be prepared in the hospital pharmacy. This is the first report of serum concentrations measures in pediatric CT therapy for this combination of drugs. A bioanalytical method was developed for identification and simultaneous quantification of SDZ and PYR by High Performance Liquid Chromatography (HPLC) with UV detection. The validated method was applied to residual serum samples obtained from 6 pediatric patients undergoing treatment with SDZ 42.20 a 93.70 mg/kg/day and </span><span style="font-family:Verdana;">PYR 0.77 a 2.70 mg/kg/day. Sample pretreatment consisted </span></span><span style="font-family:Verdana;">on</span><span style="font-family:Verdana;"> a</span><span style="font-family:""><span style="font-family:Verdana;"> deproteini</span><span style="font-family:Verdana;">zation step followed by centrifugation and then injection of supernatant.</span><span style="font-family:Verdana;"> Limit of Detection (LOD) and Quantification (LOQ) were (0.17 ± 0.02 and 0.13 ± 0.02) μg/mL and (0.46 ± 0.01 and 0.36 ± 0.01) μg/mL for SDZ and PYR respectively, with an appropriate linear range. Concentrations range found </span><span style="font-family:Verdana;">were (<LOD</span></span><span style="font-family:Verdana;"> - </span><span style="font-family:Verdana;">162.04 ± 0.02) μg/mL for SDZ and (<LOD</span><span style="font-family:Verdana;"> - </span><span style="font-family:Verdana;">7.30 ± 0.03) </span><span style="font-family:""><span style="font-family:Verdana;">μg/mL for PYR. We developed and validated in real pediatric samples, an acute, pre</span><span style="font-family:Verdana;">cise and low-cost method for quantification of SDZ and PYR using a </span><span style="font-family:Verdana;">non-so</span><span style="font-family:Verdana;">phisticate chromatographic equipment, suitable for hospital therapeutic </span><span style="font-family:Verdana;">monitoring for public health system.展开更多
文摘Peptides play multiple functions in cellular processes and are considered an attractive paradigm for the development of novel drugs and therapeutic approaches. However, the complexity of their pharmacokinetics/pharmacodynamics and physicochemical properties presents challenges in their development. Currently, there is no single analytical method that fully meets the requirements for studying peptide drug pharmacokinetics. Interdisciplinary teams and multiple technical platforms are required to address these challenges. This article explores the pharmacokinetics, bioanalytical methods, challenges, and strategies in the development of peptide drugs. As our understanding of peptide drug pharmacokinetics and bioanalytical characteristics deepens, it will facilitate their development and provide scientific evidence for rational clinical use.
基金supported by “Ministero della Salute” “Ricerca corrente 2015” grant to E.C.
文摘A new method using high-performance liquid chromatography coupled with ultra violet detection(HPLC–UV)was developed and validated for the simultaneous quantification of atazanavir,dolutegravir,darunavir,efavirenz,etravirine lopinavir,raltegravir,rilpivirine and tipranavir in human plasma.For the first time we reported here the development and validation of an HPLC–UV assay to quantify the frequently administered 9antiretroviral compounds including dolutegravir and rilpivirine.A simple solid phase extraction procedure was applied to 500 μL aliquots of plasma.The chromatographic separation of the drugs and internal standard(quinoxaline) was achieved with a gradient of acetonitrile and sodium acetate buffer on a C_(18) reverse-phase analytical column with a 25 min analytical run time.Calibration curves were optimised according to the therapeutic range of drug concentrations in patients,and the coefficient of determination(r^2) was higher than0.99 for all analytes.Mean intraday and interday precisions(RSD) for all compounds were less than 15.0%,and the mean accuracy(% deviation from nominal concentration) was also found to be less than 15.0%.Extraction recovery range was between 80% and 120% for all drugs analysed.The solid phase extraction and HPLC–UV method enable a specific,sensitive,and reliable simultaneous determination of nine antiretroviral agents in plasma.Good extraction efficiency and low limit of HPLC–UV quantification make this method suitable for use in clinical trials and therapeutic drug monitoring.
文摘Abstract: A Selective new reagent Wazo-1 was prepared. This paper studied the properties of its fluorescence and UV- Spectrum. A new fluorescence method for the determination of clacium is developed. Wazo-1 reacts with calcium. forms calcium complex(Ex=297nm; Em=370nm). The interference of Mg(Ⅱ)has been studied. The reagent has better selectivity to Ca(Ⅱ) in the presence of large amount of Mg(Ⅱ). Fluorescence method has-been used for determination of microamounts of calcium in serum with new reagent Wazo-1.The results obtained are favourable.
文摘A liquid chromatography tandem mass spectrometry (LC-MS/MS) based method was developed for the simultaneous monitoring plasma levels of Sitagliptin (STG) and Pioglitazone (PIO) for applicability to pharmacokinetic studies. The method was based on HPLC separation on the reversed phase Phenomenex Synergy C18 column (30 mm length, 4.6 mm internal diameter, and 4.0 μm particle size) at a temperature of 40?C using a binary gradient mobile phase consisting of methanol and 2 mM ammonium acetate buffer pH adjusted to 4.5 with acetic acid, at a flow rate of 1 mL?min?1. Tolbutamide was used as an internal standard. Detection of analytes was achieved with LC-MS/MS system in Multiple Reaction Monitoring (MRM) mode. The method was validated over concentration range of 10.98 - 2091.77 ng?mL?1 for SIT and 8.25 - 1571.63 ng?mL?1 for PIO and lower limit of quantification was 10.98 ng?mL?1 and 8.25 ng?mL?1 for STG and PIO respectively. Recoveries from spiked controls were within acceptance criteria for all the analytes and internal standard at all QC levels. Within batch and between batch accuracy for STG was found within 96.9% - 100.3% and for PIO was found within 100.0% - 104.3%. Within batch and between batch precision for STG was less than 3.1% CV (coefficient of variation) and for PIO was less than 5.3% CV at all concentrations levels. This method was successfully applied to monitor pharmacokinetics profile of both STG and PIO on simultaneous oral administration to rats. This method can be applicable for pharmacokinetic drug-drug interaction studies.
文摘Repaglinide is type 2 short acting anti-diabetic drug which is primarily metabolized by CYP2C8 and CYP3A4 and is also a substrate of influx transporter OATP1B1. HIV drugs are potent inhibitors of CYP3A4 and OATP transporters. Several drug-drug interactions (DDIs) were noticed when protease inhibitors (PIs) coadministered with drugs metabolized by CYP3A4. The PIs are also potent mechanism based inhibitors, out which ritonavir is most potent. In the current study we evaluated in vitro (mouse and human liver microsomes) and in vivo DDIs of repaglinide with anti-HIV drugs. Out of the following tested drugs (Amprenavir, Indinavir, Nelfinavir, Ritonavir, Saquinavir, Delavirdine, Maraviroc, Efavirenz, Nevirapine and Ketoconazole) Amprenavir (APV), Ritonavir (RTV) and Ketoconazole (KTZ) showed inhibition of OH-repaglinide formation in human and mouse liver microsomes. The positive reversible inhibitions were further tested for irreversible inhibitions where we didn’t observe any irreversible inhibitions. In vitro inhibitions were further evaluated in the in vivo pharmacokinetics (mouse) where repaglinide pharmacokinetics was altered by RTV and KTZ. The DDIs in both studies were very strong;the dose of repaglinide is reduced to 20 fold. In conclusion, there could be possible DDIs when RTV dosed with repaglinide;we have also demonstrated that mouse could be useful preclinical tool when used in conjunction with in vitro screening models for DDIs.
文摘<span style="font-family:""><span style="font-family:Verdana;">Infection with </span><i><span style="font-family:Verdana;">Toxoplasma gondii</span></i><span style="font-family:Verdana;">, is one of the most widespread zoonoses in the world. Congenital Toxoplasmosis (CT) is particularly risky due to its fetal </span><span style="font-family:Verdana;">complications. Sulfadiazine (SDZ) and Pyrimethamine (PYR) are usually </span><span style="font-family:Verdana;">used </span><span style="font-family:Verdana;">for CT treatment in Argentina, to prevent morbidity. Due to the lack of </span><span style="font-family:Verdana;">commercial pediatric formulations, these must be prepared in the hospital pharmacy. This is the first report of serum concentrations measures in pediatric CT therapy for this combination of drugs. A bioanalytical method was developed for identification and simultaneous quantification of SDZ and PYR by High Performance Liquid Chromatography (HPLC) with UV detection. The validated method was applied to residual serum samples obtained from 6 pediatric patients undergoing treatment with SDZ 42.20 a 93.70 mg/kg/day and </span><span style="font-family:Verdana;">PYR 0.77 a 2.70 mg/kg/day. Sample pretreatment consisted </span></span><span style="font-family:Verdana;">on</span><span style="font-family:Verdana;"> a</span><span style="font-family:""><span style="font-family:Verdana;"> deproteini</span><span style="font-family:Verdana;">zation step followed by centrifugation and then injection of supernatant.</span><span style="font-family:Verdana;"> Limit of Detection (LOD) and Quantification (LOQ) were (0.17 ± 0.02 and 0.13 ± 0.02) μg/mL and (0.46 ± 0.01 and 0.36 ± 0.01) μg/mL for SDZ and PYR respectively, with an appropriate linear range. Concentrations range found </span><span style="font-family:Verdana;">were (<LOD</span></span><span style="font-family:Verdana;"> - </span><span style="font-family:Verdana;">162.04 ± 0.02) μg/mL for SDZ and (<LOD</span><span style="font-family:Verdana;"> - </span><span style="font-family:Verdana;">7.30 ± 0.03) </span><span style="font-family:""><span style="font-family:Verdana;">μg/mL for PYR. We developed and validated in real pediatric samples, an acute, pre</span><span style="font-family:Verdana;">cise and low-cost method for quantification of SDZ and PYR using a </span><span style="font-family:Verdana;">non-so</span><span style="font-family:Verdana;">phisticate chromatographic equipment, suitable for hospital therapeutic </span><span style="font-family:Verdana;">monitoring for public health system.
