Oral administration has been widely regarded as the most conve nient,quick and safe approach compared to other routes of drug delivery.However,oral absorption of drugs is often limited due to rigorous environments and...Oral administration has been widely regarded as the most conve nient,quick and safe approach compared to other routes of drug delivery.However,oral absorption of drugs is often limited due to rigorous environments and complex obstacles in gastrointestinal tract.Having received considerable attention,biomacromolecules have been applied for oral drug delivery to improve the bioavailability,which could be attributed to its stability and unique bioactivities,including intestinal adhesion,opening of epithelial tight junctions,inhibiting cell efflux and regulating relative protein expression.Specifically,enhancing intestinal permeability has been regarded as a promising strategy for improving bioavailability of oral drug delivery.In this review,a series of biomacromolecules and the related mechanisms of increasing intestinal permeability for enhanced oral bioavailability are comprehensively classified and elucidated.In addition,recent advances in biomacromolecules based oral delivery and related future directions are mentioned and predicted in this review article.展开更多
Results are presented of an ongoing investigation into modeling friction in fiuidized dense-phase pneumatic transport of bulk solids. Many popular modeling methods of the solids friction use the dimen- sionless solids...Results are presented of an ongoing investigation into modeling friction in fiuidized dense-phase pneumatic transport of bulk solids. Many popular modeling methods of the solids friction use the dimen- sionless solids loading ratio and Froude number. When evaluated under proper scale-up conditions of pipe diameter and length, many of these models have resulted in significant inaccuracy. A technique for modeling solids friction has been developed using a new combination of dimensionless numbers, volu- metric loading ratio and the ratio of particle free settling velocity to superficial conveying air velocity, to replace the solids loading ratio and Froude number. The models developed using the new formalism were evaluated for accuracy and stability under significant scale-up conditions for four different prod- ucts conveyed through four different test rigs （subject to diameter and length scale-up conditions）. The new model considerably improves predictions compared with those obtained using the existing model, especially in the dense-phase region. Whereas the latter yields absolute average relative errors varying between 10% and 86%, the former yielded results with errors from 4% to 20% for a wide range of scale-up conditions. This represents a more reliable and narrower range of prediction that is suitable for industrial scale-up requirements.展开更多
基金the National Natural Science Foundation of China(No.51803152)Natural Science Foundation of Shanghai(No.19ZR1478800)。
文摘Oral administration has been widely regarded as the most conve nient,quick and safe approach compared to other routes of drug delivery.However,oral absorption of drugs is often limited due to rigorous environments and complex obstacles in gastrointestinal tract.Having received considerable attention,biomacromolecules have been applied for oral drug delivery to improve the bioavailability,which could be attributed to its stability and unique bioactivities,including intestinal adhesion,opening of epithelial tight junctions,inhibiting cell efflux and regulating relative protein expression.Specifically,enhancing intestinal permeability has been regarded as a promising strategy for improving bioavailability of oral drug delivery.In this review,a series of biomacromolecules and the related mechanisms of increasing intestinal permeability for enhanced oral bioavailability are comprehensively classified and elucidated.In addition,recent advances in biomacromolecules based oral delivery and related future directions are mentioned and predicted in this review article.
文摘Results are presented of an ongoing investigation into modeling friction in fiuidized dense-phase pneumatic transport of bulk solids. Many popular modeling methods of the solids friction use the dimen- sionless solids loading ratio and Froude number. When evaluated under proper scale-up conditions of pipe diameter and length, many of these models have resulted in significant inaccuracy. A technique for modeling solids friction has been developed using a new combination of dimensionless numbers, volu- metric loading ratio and the ratio of particle free settling velocity to superficial conveying air velocity, to replace the solids loading ratio and Froude number. The models developed using the new formalism were evaluated for accuracy and stability under significant scale-up conditions for four different prod- ucts conveyed through four different test rigs （subject to diameter and length scale-up conditions）. The new model considerably improves predictions compared with those obtained using the existing model, especially in the dense-phase region. Whereas the latter yields absolute average relative errors varying between 10% and 86%, the former yielded results with errors from 4% to 20% for a wide range of scale-up conditions. This represents a more reliable and narrower range of prediction that is suitable for industrial scale-up requirements.
