The Experts below are selected from a list of 31086 Experts worldwide ranked by ideXlab platform
Christopher P Bowers - One of the best experts on this subject based on the ideXlab platform.
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magnetophoresis for enhancing transdermal drug delivery mechanistic studies and Patch Design
Journal of Controlled Release, 2010Co-Authors: Narasimha S Murthy, Srinivasa M Sammeta, Christopher P BowersAbstract:Abstract Magnetophoresis is a method of enhancement of drug permeation across the biological barriers by application of magnetic field. The present study investigated the mechanistic aspects of magnetophoretic transdermal drug delivery and also assessed the feasibility of Designing a magnetophoretic transdermal Patch system for the delivery of lidocaine. In vitro drug permeation studies were carried out across the porcine epidermis at different magnetic field strengths. The magnetophoretic drug permeation “flux enhancement factor” was found to increase with the applied magnetic field strength. The mechanistic studies revealed that the magnetic field applied in this study did not modulate permeability of the stratum corneum barrier. The predominant mechanism responsible for magnetically mediated drug permeation enhancement was found to be “magnetokinesis”. The octanol/water partition coefficient of drugs was also found to increase when exposed to the magnetic field. A reservoir type transdermal Patch system with a magnetic backing was Designed for in vivo studies. The dermal bioavailability (AUC 0–6 h ) from the magnetophoretic Patch system in vivo , in rats was significantly higher than the similarly Designed non-magnetic control Patch.
Narasimha S Murthy - One of the best experts on this subject based on the ideXlab platform.
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magnetophoresis for enhancing transdermal drug delivery mechanistic studies and Patch Design
Journal of Controlled Release, 2010Co-Authors: Narasimha S Murthy, Srinivasa M Sammeta, Christopher P BowersAbstract:Abstract Magnetophoresis is a method of enhancement of drug permeation across the biological barriers by application of magnetic field. The present study investigated the mechanistic aspects of magnetophoretic transdermal drug delivery and also assessed the feasibility of Designing a magnetophoretic transdermal Patch system for the delivery of lidocaine. In vitro drug permeation studies were carried out across the porcine epidermis at different magnetic field strengths. The magnetophoretic drug permeation “flux enhancement factor” was found to increase with the applied magnetic field strength. The mechanistic studies revealed that the magnetic field applied in this study did not modulate permeability of the stratum corneum barrier. The predominant mechanism responsible for magnetically mediated drug permeation enhancement was found to be “magnetokinesis”. The octanol/water partition coefficient of drugs was also found to increase when exposed to the magnetic field. A reservoir type transdermal Patch system with a magnetic backing was Designed for in vivo studies. The dermal bioavailability (AUC 0–6 h ) from the magnetophoretic Patch system in vivo , in rats was significantly higher than the similarly Designed non-magnetic control Patch.
D R Jackson - One of the best experts on this subject based on the ideXlab platform.
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2 d periodic leaky wave antennas part i metal Patch Design
IEEE Transactions on Antennas and Propagation, 2005Co-Authors: Tianxia Zhao, D R Jackson, J T Williams, H Y D Yang, A A OlinerAbstract:The far-field radiation characteristics of a two-dimensional (2-D) periodic leaky-wave antenna (LWA) constructed from a periodic array of metal Patches on a grounded dielectric substrate is investigated. A simple dipole source is used as the excitation. Reciprocity together with a periodic spectral-domain method of moments is used to calculate the far-field pattern. Design rules for the scan angle, the substrate dielectric constant, and the periodicity are provided. Finally, a comparison of the 2-D periodic LWA and a dielectric-layer LWA is given to show the similar performance of the two antennas.
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microstrip Patch Designs that do not excite surface waves
IEEE Transactions on Antennas and Propagation, 1993Co-Authors: D R Jackson, J T Williams, A K Bhattacharyya, R Smith, S J Buchheit, Stuart A LongAbstract:Two variations of a circular microstrip Patch Design are presented which excite very little surface wave power. Both of the Designs are based on the principle that a ring of magnetic current in a substrate (which models the Patches) will not excite the dominant TM/sub 0/ surface wave if the radius of the ring is a particular critical value. Numerical results for radiation efficiency and radiated field strength from a ring of magnetic current are shown to verify this basic Design principle. The proposed Patch Designs are chosen to have a radius equal to this critical value, while maintaining resonance at the Design frequency. The Designs excite very little surface-wave power, and thus have smoother radiation patterns when mounted on finite-size ground planes, due to reduced surface-wave diffraction. They also have reduced mutual coupling, due to the reduced surface-wave excitation. Measured results for radiation patterns and field strength within the substrate are presented to verify the theoretical concepts. >
J T Williams - One of the best experts on this subject based on the ideXlab platform.
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2 d periodic leaky wave antennas part i metal Patch Design
IEEE Transactions on Antennas and Propagation, 2005Co-Authors: Tianxia Zhao, D R Jackson, J T Williams, H Y D Yang, A A OlinerAbstract:The far-field radiation characteristics of a two-dimensional (2-D) periodic leaky-wave antenna (LWA) constructed from a periodic array of metal Patches on a grounded dielectric substrate is investigated. A simple dipole source is used as the excitation. Reciprocity together with a periodic spectral-domain method of moments is used to calculate the far-field pattern. Design rules for the scan angle, the substrate dielectric constant, and the periodicity are provided. Finally, a comparison of the 2-D periodic LWA and a dielectric-layer LWA is given to show the similar performance of the two antennas.
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microstrip Patch Designs that do not excite surface waves
IEEE Transactions on Antennas and Propagation, 1993Co-Authors: D R Jackson, J T Williams, A K Bhattacharyya, R Smith, S J Buchheit, Stuart A LongAbstract:Two variations of a circular microstrip Patch Design are presented which excite very little surface wave power. Both of the Designs are based on the principle that a ring of magnetic current in a substrate (which models the Patches) will not excite the dominant TM/sub 0/ surface wave if the radius of the ring is a particular critical value. Numerical results for radiation efficiency and radiated field strength from a ring of magnetic current are shown to verify this basic Design principle. The proposed Patch Designs are chosen to have a radius equal to this critical value, while maintaining resonance at the Design frequency. The Designs excite very little surface-wave power, and thus have smoother radiation patterns when mounted on finite-size ground planes, due to reduced surface-wave diffraction. They also have reduced mutual coupling, due to the reduced surface-wave excitation. Measured results for radiation patterns and field strength within the substrate are presented to verify the theoretical concepts. >
Srinivasa M Sammeta - One of the best experts on this subject based on the ideXlab platform.
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magnetophoresis for enhancing transdermal drug delivery mechanistic studies and Patch Design
Journal of Controlled Release, 2010Co-Authors: Narasimha S Murthy, Srinivasa M Sammeta, Christopher P BowersAbstract:Abstract Magnetophoresis is a method of enhancement of drug permeation across the biological barriers by application of magnetic field. The present study investigated the mechanistic aspects of magnetophoretic transdermal drug delivery and also assessed the feasibility of Designing a magnetophoretic transdermal Patch system for the delivery of lidocaine. In vitro drug permeation studies were carried out across the porcine epidermis at different magnetic field strengths. The magnetophoretic drug permeation “flux enhancement factor” was found to increase with the applied magnetic field strength. The mechanistic studies revealed that the magnetic field applied in this study did not modulate permeability of the stratum corneum barrier. The predominant mechanism responsible for magnetically mediated drug permeation enhancement was found to be “magnetokinesis”. The octanol/water partition coefficient of drugs was also found to increase when exposed to the magnetic field. A reservoir type transdermal Patch system with a magnetic backing was Designed for in vivo studies. The dermal bioavailability (AUC 0–6 h ) from the magnetophoretic Patch system in vivo , in rats was significantly higher than the similarly Designed non-magnetic control Patch.