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Joke A. Bouwstra - One of the best experts on this subject based on the ideXlab platform.
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Compartmental Modeling of Transdermal Iontophoretic Transport II: In Vivo Model Derivation and Application
Pharmaceutical Research, 2005Co-Authors: Akhmad Kharis Nugroho, Oscar Della-pasqua, Meindert Danhof, Joke A. BouwstraAbstract:Purpose. This study was aimed to develop a family of Compartmental models to describe in a strictly quantitative manner the transdermal iontophoretic transport of drugs in vivo . The new models are based on previously proposed Compartmental models for the transport in vitro . Methods. The novel in vivo model considers two separate models to describe the input into the systemic circulation: a) constant input and b) time-variant input. Analogous to the in vitro models, the in vivo models contain four parameters: 1) kinetic lag time ( t _ L ), 2) steady-state flux during iontophoresis ( J _ ss ), 3) skin release rate constant ( K _ R ), and 4) passive flux in the post-iontophoretic period ( J _ pas ). The elimination from the systemic circulation is described by a) the one-compartment and b) the two-compartment pharmacokinetic models. The models were applied to characterize the observed plasma concentration vs. time data following single-dose iontophoretic delivery of growth hormone-releasing factor (GRF) and R-apomorphine. Moreover, the models were also used to simulate the observed plasma concentration vs. time profiles following a two-dose transdermal iontophoretic administration of alniditan. Results. The time-variant input models were superior to the constant input models and appropriately converged to the observed data of GRF and R-apomorphine allowing the estimation of J _ ss , K _ R , and J _ pas . In most cases, the values of t _ L were negligible. The estimated J _ ss and the in vivo flux profiles of GRF and R-apomorphine were similar to those obtained using the deconvolution method. The two-dose iontophoretic transport of alniditan was properly simulated using the proposed time-variant input model indicating the utility of the model to predict and to simulate the drug transport by a multiple-dose iontophoresis. Moreover, the use of the Compartmental Modeling approach to derive an in vitro-in vivo correlation for R-apomorphine was demonstrated. This approach was also used to identify the optimum in vitro model that closely mimics the in vivo iontophoretic transport of R-apomorphine. Conclusions. The developed in vivo models demonstrate their consistency and capability to describe the in vivo iontophoretic drug transport. This Compartmental Modeling approach provides a scientific basis to examine in vitro-in vivo correlations of drug transport by iontophoresis.
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Compartmental Modeling of Transdermal Iontophoretic Transport: I. In Vitro Model Derivation and Application
Pharmaceutical Research, 2004Co-Authors: Akhmad Kharis Nugroho, Oscar Della-pasqua, Meindert Danhof, Joke A. BouwstraAbstract:Purpose . The objective of this study was to develop a family of Compartmental models to describe in a strictly quantitative manner the transdermal iontophoretic transport of drugs in vitro. Methods . Two structurally different Compartmental models describing the in vitro transport during iontophoresis and one Compartmental model describing the in vitro transport in post-iontophoretic period are proposed. These models are based on the mass transfer from the donor compartment to the acceptor compartment via the skin as an intermediate compartment. In these models, transdermal iontophoretic transport is characterized by 5 parameters: 1) kinetic lag time ( t _L), 2) steady-state flux during iontophoresis ( J _ss), 3) skin release rate constant ( K _R), 4) the first-order rate constant of the iontophoretic driving force from the skin to the acceptor compartment ( I _1), and 5) passive flux in the post-iontophoretic period ( J _pas). The developed models were applied to data on the iontophoretic transport in human stratum corneum in vitro of R-apomorphine after pretreatment with phosphate buffered saline pH 7.4 (PBS) and after pretreatment with surfactant (SFC), as well as the iontophoretic transport of 0.5 mg ml^-1 rotigotine at pH 5 (RTG). Results . All of the proposed models could be fitted to the transport data of PBS, SFC, and RTG groups both during the iontophoresis and in the post-iontophoretic period. The incorporation of parameter I _1 failed to improve the fitting performance of the model. This might indicate a negligible contribution of iontophoretic driving force to the mass transfer in the direction from the skin to the acceptor compartment, although it plays an important role in loading the skin with the drug. The estimated values of J _ss of PBS, SFC, and RTG were identical (p > 0.05) to the values obtained with the diffusion lag time method. Moreover, time required to achieve steady-state flux can be estimated based on the parameter t _L and the reciprocal value of parameter K _R. In addition, accumulation of drug molecules in the skin is reflected in a reduction of the value of the K _R parameter. Conclusions . The developed in vitro models demonstrated their strength and consistency to describe the drug transport during and post-iontophoresis.
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Compartmental Modeling of transdermal iontophoretic transport ii in vivo model derivation and application
Pharmaceutical Research, 2004Co-Authors: Akhmad Kharis Nugroho, Meindert Danhof, Oscar Dellapasqua, Joke A. BouwstraAbstract:Purpose. This study was aimed to develop a family of Compartmental models to describe in a strictly quantitative manner the transdermal iontophoretic transport of drugs in vivo. The new models are based on previously proposed Compartmental models for the transport in vitro.
Akhmad Kharis Nugroho - One of the best experts on this subject based on the ideXlab platform.
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Compartmental Modeling approach of losartan transdermal transport in vitro
INDONESIAN JOURNAL OF PHARMACY, 2014Co-Authors: Akhmad Kharis NugrohoAbstract:Development of losartan in transdermal formulation is important due to its low oral bioavailability. Optimal transdermal formulation requires transport mechanism understanding. This study was aimed to develop and evaluate Compartmental Modeling of losartan transdermal transport in vitro to fulfil this demand. Losartan solution (10g/L in 20% propylene glycol) was filled into the acceptor phase of a vertical diffusion-cells system. The fresh rat skin (pretreated with oleic acid for 1 hour) was used as the transport membrane separating the donor and the acceptor phase, which was filled with phosphate-buffered-saline pH 7.4. During 30h, samples were collected and analyzed using HPLC method. Four Compartmental models were proposed, i.e. models with one (model 1) or two (model 2) lag-compartment(s) either with a zero-order (model A) or a first- order (model B) drug input from donor to the skin. WinSAAM was used to evaluate the models based on the parameters: 1) visual goodness of fit ( GOF ); and 2) Corrected Akaike's Information Criterion ( AICc ). Both the GOF and AICc evaluations indicated model 2-A as the best model describing losartan transdermal transport. The model suggested that after reaching the upper layer of skin at a constant rate, losartan transport was split into two flows. Both flows are transited in two separate lag-compartments before reaching into the acceptor phase. Key words: Transdermal, Losartan, Modeling, Lag-compartment, WinSAAM
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Compartmental Modeling of Transdermal Iontophoretic Transport II: In Vivo Model Derivation and Application
Pharmaceutical Research, 2005Co-Authors: Akhmad Kharis Nugroho, Oscar Della-pasqua, Meindert Danhof, Joke A. BouwstraAbstract:Purpose. This study was aimed to develop a family of Compartmental models to describe in a strictly quantitative manner the transdermal iontophoretic transport of drugs in vivo . The new models are based on previously proposed Compartmental models for the transport in vitro . Methods. The novel in vivo model considers two separate models to describe the input into the systemic circulation: a) constant input and b) time-variant input. Analogous to the in vitro models, the in vivo models contain four parameters: 1) kinetic lag time ( t _ L ), 2) steady-state flux during iontophoresis ( J _ ss ), 3) skin release rate constant ( K _ R ), and 4) passive flux in the post-iontophoretic period ( J _ pas ). The elimination from the systemic circulation is described by a) the one-compartment and b) the two-compartment pharmacokinetic models. The models were applied to characterize the observed plasma concentration vs. time data following single-dose iontophoretic delivery of growth hormone-releasing factor (GRF) and R-apomorphine. Moreover, the models were also used to simulate the observed plasma concentration vs. time profiles following a two-dose transdermal iontophoretic administration of alniditan. Results. The time-variant input models were superior to the constant input models and appropriately converged to the observed data of GRF and R-apomorphine allowing the estimation of J _ ss , K _ R , and J _ pas . In most cases, the values of t _ L were negligible. The estimated J _ ss and the in vivo flux profiles of GRF and R-apomorphine were similar to those obtained using the deconvolution method. The two-dose iontophoretic transport of alniditan was properly simulated using the proposed time-variant input model indicating the utility of the model to predict and to simulate the drug transport by a multiple-dose iontophoresis. Moreover, the use of the Compartmental Modeling approach to derive an in vitro-in vivo correlation for R-apomorphine was demonstrated. This approach was also used to identify the optimum in vitro model that closely mimics the in vivo iontophoretic transport of R-apomorphine. Conclusions. The developed in vivo models demonstrate their consistency and capability to describe the in vivo iontophoretic drug transport. This Compartmental Modeling approach provides a scientific basis to examine in vitro-in vivo correlations of drug transport by iontophoresis.
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Compartmental Modeling of Transdermal Iontophoretic Transport: I. In Vitro Model Derivation and Application
Pharmaceutical Research, 2004Co-Authors: Akhmad Kharis Nugroho, Oscar Della-pasqua, Meindert Danhof, Joke A. BouwstraAbstract:Purpose . The objective of this study was to develop a family of Compartmental models to describe in a strictly quantitative manner the transdermal iontophoretic transport of drugs in vitro. Methods . Two structurally different Compartmental models describing the in vitro transport during iontophoresis and one Compartmental model describing the in vitro transport in post-iontophoretic period are proposed. These models are based on the mass transfer from the donor compartment to the acceptor compartment via the skin as an intermediate compartment. In these models, transdermal iontophoretic transport is characterized by 5 parameters: 1) kinetic lag time ( t _L), 2) steady-state flux during iontophoresis ( J _ss), 3) skin release rate constant ( K _R), 4) the first-order rate constant of the iontophoretic driving force from the skin to the acceptor compartment ( I _1), and 5) passive flux in the post-iontophoretic period ( J _pas). The developed models were applied to data on the iontophoretic transport in human stratum corneum in vitro of R-apomorphine after pretreatment with phosphate buffered saline pH 7.4 (PBS) and after pretreatment with surfactant (SFC), as well as the iontophoretic transport of 0.5 mg ml^-1 rotigotine at pH 5 (RTG). Results . All of the proposed models could be fitted to the transport data of PBS, SFC, and RTG groups both during the iontophoresis and in the post-iontophoretic period. The incorporation of parameter I _1 failed to improve the fitting performance of the model. This might indicate a negligible contribution of iontophoretic driving force to the mass transfer in the direction from the skin to the acceptor compartment, although it plays an important role in loading the skin with the drug. The estimated values of J _ss of PBS, SFC, and RTG were identical (p > 0.05) to the values obtained with the diffusion lag time method. Moreover, time required to achieve steady-state flux can be estimated based on the parameter t _L and the reciprocal value of parameter K _R. In addition, accumulation of drug molecules in the skin is reflected in a reduction of the value of the K _R parameter. Conclusions . The developed in vitro models demonstrated their strength and consistency to describe the drug transport during and post-iontophoresis.
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Compartmental Modeling of transdermal iontophoretic transport ii in vivo model derivation and application
Pharmaceutical Research, 2004Co-Authors: Akhmad Kharis Nugroho, Meindert Danhof, Oscar Dellapasqua, Joke A. BouwstraAbstract:Purpose. This study was aimed to develop a family of Compartmental models to describe in a strictly quantitative manner the transdermal iontophoretic transport of drugs in vivo. The new models are based on previously proposed Compartmental models for the transport in vitro.
Meindert Danhof - One of the best experts on this subject based on the ideXlab platform.
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Compartmental Modeling of Transdermal Iontophoretic Transport II: In Vivo Model Derivation and Application
Pharmaceutical Research, 2005Co-Authors: Akhmad Kharis Nugroho, Oscar Della-pasqua, Meindert Danhof, Joke A. BouwstraAbstract:Purpose. This study was aimed to develop a family of Compartmental models to describe in a strictly quantitative manner the transdermal iontophoretic transport of drugs in vivo . The new models are based on previously proposed Compartmental models for the transport in vitro . Methods. The novel in vivo model considers two separate models to describe the input into the systemic circulation: a) constant input and b) time-variant input. Analogous to the in vitro models, the in vivo models contain four parameters: 1) kinetic lag time ( t _ L ), 2) steady-state flux during iontophoresis ( J _ ss ), 3) skin release rate constant ( K _ R ), and 4) passive flux in the post-iontophoretic period ( J _ pas ). The elimination from the systemic circulation is described by a) the one-compartment and b) the two-compartment pharmacokinetic models. The models were applied to characterize the observed plasma concentration vs. time data following single-dose iontophoretic delivery of growth hormone-releasing factor (GRF) and R-apomorphine. Moreover, the models were also used to simulate the observed plasma concentration vs. time profiles following a two-dose transdermal iontophoretic administration of alniditan. Results. The time-variant input models were superior to the constant input models and appropriately converged to the observed data of GRF and R-apomorphine allowing the estimation of J _ ss , K _ R , and J _ pas . In most cases, the values of t _ L were negligible. The estimated J _ ss and the in vivo flux profiles of GRF and R-apomorphine were similar to those obtained using the deconvolution method. The two-dose iontophoretic transport of alniditan was properly simulated using the proposed time-variant input model indicating the utility of the model to predict and to simulate the drug transport by a multiple-dose iontophoresis. Moreover, the use of the Compartmental Modeling approach to derive an in vitro-in vivo correlation for R-apomorphine was demonstrated. This approach was also used to identify the optimum in vitro model that closely mimics the in vivo iontophoretic transport of R-apomorphine. Conclusions. The developed in vivo models demonstrate their consistency and capability to describe the in vivo iontophoretic drug transport. This Compartmental Modeling approach provides a scientific basis to examine in vitro-in vivo correlations of drug transport by iontophoresis.
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Compartmental Modeling of Transdermal Iontophoretic Transport: I. In Vitro Model Derivation and Application
Pharmaceutical Research, 2004Co-Authors: Akhmad Kharis Nugroho, Oscar Della-pasqua, Meindert Danhof, Joke A. BouwstraAbstract:Purpose . The objective of this study was to develop a family of Compartmental models to describe in a strictly quantitative manner the transdermal iontophoretic transport of drugs in vitro. Methods . Two structurally different Compartmental models describing the in vitro transport during iontophoresis and one Compartmental model describing the in vitro transport in post-iontophoretic period are proposed. These models are based on the mass transfer from the donor compartment to the acceptor compartment via the skin as an intermediate compartment. In these models, transdermal iontophoretic transport is characterized by 5 parameters: 1) kinetic lag time ( t _L), 2) steady-state flux during iontophoresis ( J _ss), 3) skin release rate constant ( K _R), 4) the first-order rate constant of the iontophoretic driving force from the skin to the acceptor compartment ( I _1), and 5) passive flux in the post-iontophoretic period ( J _pas). The developed models were applied to data on the iontophoretic transport in human stratum corneum in vitro of R-apomorphine after pretreatment with phosphate buffered saline pH 7.4 (PBS) and after pretreatment with surfactant (SFC), as well as the iontophoretic transport of 0.5 mg ml^-1 rotigotine at pH 5 (RTG). Results . All of the proposed models could be fitted to the transport data of PBS, SFC, and RTG groups both during the iontophoresis and in the post-iontophoretic period. The incorporation of parameter I _1 failed to improve the fitting performance of the model. This might indicate a negligible contribution of iontophoretic driving force to the mass transfer in the direction from the skin to the acceptor compartment, although it plays an important role in loading the skin with the drug. The estimated values of J _ss of PBS, SFC, and RTG were identical (p > 0.05) to the values obtained with the diffusion lag time method. Moreover, time required to achieve steady-state flux can be estimated based on the parameter t _L and the reciprocal value of parameter K _R. In addition, accumulation of drug molecules in the skin is reflected in a reduction of the value of the K _R parameter. Conclusions . The developed in vitro models demonstrated their strength and consistency to describe the drug transport during and post-iontophoresis.
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Compartmental Modeling of transdermal iontophoretic transport ii in vivo model derivation and application
Pharmaceutical Research, 2004Co-Authors: Akhmad Kharis Nugroho, Meindert Danhof, Oscar Dellapasqua, Joke A. BouwstraAbstract:Purpose. This study was aimed to develop a family of Compartmental models to describe in a strictly quantitative manner the transdermal iontophoretic transport of drugs in vivo. The new models are based on previously proposed Compartmental models for the transport in vitro.
Oscar Della-pasqua - One of the best experts on this subject based on the ideXlab platform.
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Compartmental Modeling of Transdermal Iontophoretic Transport II: In Vivo Model Derivation and Application
Pharmaceutical Research, 2005Co-Authors: Akhmad Kharis Nugroho, Oscar Della-pasqua, Meindert Danhof, Joke A. BouwstraAbstract:Purpose. This study was aimed to develop a family of Compartmental models to describe in a strictly quantitative manner the transdermal iontophoretic transport of drugs in vivo . The new models are based on previously proposed Compartmental models for the transport in vitro . Methods. The novel in vivo model considers two separate models to describe the input into the systemic circulation: a) constant input and b) time-variant input. Analogous to the in vitro models, the in vivo models contain four parameters: 1) kinetic lag time ( t _ L ), 2) steady-state flux during iontophoresis ( J _ ss ), 3) skin release rate constant ( K _ R ), and 4) passive flux in the post-iontophoretic period ( J _ pas ). The elimination from the systemic circulation is described by a) the one-compartment and b) the two-compartment pharmacokinetic models. The models were applied to characterize the observed plasma concentration vs. time data following single-dose iontophoretic delivery of growth hormone-releasing factor (GRF) and R-apomorphine. Moreover, the models were also used to simulate the observed plasma concentration vs. time profiles following a two-dose transdermal iontophoretic administration of alniditan. Results. The time-variant input models were superior to the constant input models and appropriately converged to the observed data of GRF and R-apomorphine allowing the estimation of J _ ss , K _ R , and J _ pas . In most cases, the values of t _ L were negligible. The estimated J _ ss and the in vivo flux profiles of GRF and R-apomorphine were similar to those obtained using the deconvolution method. The two-dose iontophoretic transport of alniditan was properly simulated using the proposed time-variant input model indicating the utility of the model to predict and to simulate the drug transport by a multiple-dose iontophoresis. Moreover, the use of the Compartmental Modeling approach to derive an in vitro-in vivo correlation for R-apomorphine was demonstrated. This approach was also used to identify the optimum in vitro model that closely mimics the in vivo iontophoretic transport of R-apomorphine. Conclusions. The developed in vivo models demonstrate their consistency and capability to describe the in vivo iontophoretic drug transport. This Compartmental Modeling approach provides a scientific basis to examine in vitro-in vivo correlations of drug transport by iontophoresis.
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Compartmental Modeling of Transdermal Iontophoretic Transport: I. In Vitro Model Derivation and Application
Pharmaceutical Research, 2004Co-Authors: Akhmad Kharis Nugroho, Oscar Della-pasqua, Meindert Danhof, Joke A. BouwstraAbstract:Purpose . The objective of this study was to develop a family of Compartmental models to describe in a strictly quantitative manner the transdermal iontophoretic transport of drugs in vitro. Methods . Two structurally different Compartmental models describing the in vitro transport during iontophoresis and one Compartmental model describing the in vitro transport in post-iontophoretic period are proposed. These models are based on the mass transfer from the donor compartment to the acceptor compartment via the skin as an intermediate compartment. In these models, transdermal iontophoretic transport is characterized by 5 parameters: 1) kinetic lag time ( t _L), 2) steady-state flux during iontophoresis ( J _ss), 3) skin release rate constant ( K _R), 4) the first-order rate constant of the iontophoretic driving force from the skin to the acceptor compartment ( I _1), and 5) passive flux in the post-iontophoretic period ( J _pas). The developed models were applied to data on the iontophoretic transport in human stratum corneum in vitro of R-apomorphine after pretreatment with phosphate buffered saline pH 7.4 (PBS) and after pretreatment with surfactant (SFC), as well as the iontophoretic transport of 0.5 mg ml^-1 rotigotine at pH 5 (RTG). Results . All of the proposed models could be fitted to the transport data of PBS, SFC, and RTG groups both during the iontophoresis and in the post-iontophoretic period. The incorporation of parameter I _1 failed to improve the fitting performance of the model. This might indicate a negligible contribution of iontophoretic driving force to the mass transfer in the direction from the skin to the acceptor compartment, although it plays an important role in loading the skin with the drug. The estimated values of J _ss of PBS, SFC, and RTG were identical (p > 0.05) to the values obtained with the diffusion lag time method. Moreover, time required to achieve steady-state flux can be estimated based on the parameter t _L and the reciprocal value of parameter K _R. In addition, accumulation of drug molecules in the skin is reflected in a reduction of the value of the K _R parameter. Conclusions . The developed in vitro models demonstrated their strength and consistency to describe the drug transport during and post-iontophoresis.
Jérôme Casas - One of the best experts on this subject based on the ideXlab platform.
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Calling Behavior and Sex Pheromone Release and Storage in the Moth Chloridea virescens
Journal of Chemical Ecology, 2020Co-Authors: Stephen P. Foster, Karin G. Anderson, Jérôme CasasAbstract:Female moths release sex pheromone to attract mates. In most species, sex pheromone is produced in, and released from, a specific gland. In a previous study, we used empirical data and Compartmental Modeling to account for the major pheromone gland processes of female Chloridea virescens : synthesis, storage, catabolism and release; we found that females released little (20–30%) of their pheromone, with most catabolized. The recent publication of a new pheromone collection method led us to reinvestigate pheromone release and catabolism in C. virescens on the basis that our original study might have underestimated release rate (thereby overestimating catabolism) due to methodology and females not calling (releasing) continuously. Further we wished to compare pheromone storage/catabolism between calling and non-calling females. First, we observed calling intermittency of females. Then, using decapitated females, we used the new collection method, along with Compartmental Modeling, gland sampling and stable isotope labeling, to determine differences in pheromone release, catabolism and storage between (forced) simulated calling and non-calling females. We found, (i) intact 1 d females call intermittently; (ii) pheromone is released at a higher rate than previously determined, with simulations estimating that continuously calling females release ca. 70% of their pheromone (only 30% catabolized); (iii) extension (calling)/retraction of the ovipositor is a highly effective “on/off’ mechanism for release; (iv) both calling and non-calling females store most pheromone on or near the gland surface, but calling females catabolize less pheromone; (v) females are capable of producing and releasing pheromone very rapidly. Thus, not only is the moth pheromone gland efficient, in terms of the proportion of pheromone released Vs. catabolized, but it is highly effective at shutting on/off a high flux of pheromone for release.