A robust and smart protoporphyrin-based polymer nanoplatform, which is capable of successively recognizing the variation of biological signals and reacting with them in a dynamic mode, is successfully developed. It combines the chemotherapy and photodynamic therapy in a same system, leading to a high treatment outcome while a low adverse side effect of therapeutic agent.

Accurate modeling of gas through shale-gas reservoirs characterized by nano-meter pores where the effects of various non- Darcy flow regimes and the adsorbed-layer are important is presented and demonstrated by several examples. Quantification of gas transport may be accomplished using the transport equation that is valid for all flow regimes. This equation though needs further modification when transport is through a media where the gas is adsorbed onto the pore wall. In the presence of adsorption, there is a pore pressure dependent loss of porosity and cross-sectional area to free gas transport. The apparent gas permeability correction is accomplished for various flow regimes using the Knudsen number by consideration of the reduction of the cross-sectional area to free gas transport in the presence of adsorption. We show that transport in the adsorbed layer may contribute significantly in the total gas transport in these nanopores. An effective transport model is presented to account for the impact of adsorption through two mechanisms. First, we modify the transport equation to account for the pore-pressure dependent-reduction in the volume available to free gas transport; second, we model transport through the adsorbed layer using Fick's law of diffusion. The coupled model is then compare to conventional transport models over a wide range of reservoir properties and conditions. As pore-pressure is reduced, adsorbed phase gas desorbs into free gas and apparent permeability increases. The difference in the estimated apparent permeability with and without the consideration of the adsorption volume can be a factor of two or more at initial reservoir conditions. Diffusion on the surface of organic pores can be a substantial transport mechanism in shales depending on the pore connectivity, pore pressure, and pore size distribution in the organic pores. The interpretation of production data will be compromised without considering the effects of adsorption on apparent permeability. This work implies that permeability measurements for shale gas reservoirs must be done with methane at in-situ pore pressures. Because these corrections are pore-pressure not effective pressure dependent, effective pressure is not a valid parameter to use in quantifying the pressure dependence of these transport equations.

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Poly(lactic acid) (PLA) were grafted to both ends of Pluronic F127 (PEO-PPO-PEO) to produce novel amphiphilic PLA-F127-PLA block copolymers. The aggregation behaviors of three different modified polymers were examined by laser light scattering and transmission electron microscopic techniques. The structure of aggregates produced from moderate to long PLA segments (PLAF127-29 (230 units of PLA) and PLAF127-48 (500 units of PLA) systems, respectively) was found to be normal bi-layer vesicles. Polymer with the shortest PLA segment (PLAF127-23 (142 units of PLA)) produces aggregates with complicated onion-like vesicles containing three layers. These vesicles possess microstructure similar to many biological systems, and they exhibit desirable properties for potential applications as drug delivery vehicles.

The multidrug resistance (MDR) of cancer cells is a major obstacle in cancer chemotherapy and very few strategies are available to overcome it. Here, a new strategy is developed to codeliver a π–π stacked dual anticancer drug combination with an actively targeted, pH‐ and reduction‐sensitive polymer micellar platform for combating multidrug resistance and tumor metastasis. In contrast to other methods, two traditional chemotherapeutics, doxorubicin (DOX) and 10‐hydroxycamptothecin with complex aromatic π–π conjugated structures, are integrated into one drug delivery system via a π–π stacking interaction, which enables the released drugs to evade the recognition of drug pumps due to a slight change in the drug's molecular structure. The micelles exhibit active targeting of DOX‐resistant human breast cancer MCF‐7 cells (MCF‐7/ADR) and have the ability to control the release of the drug in response to the microenvironmental stimuli of tumor cells. As a result, the codelivery of the π–π stacked dual anticancer drug combination displays high therapeutic efficacy in the MCF‐7/ADR tumor model and successfully prevents the lung metastasis of tumor cells. The mechanism underlying the reversal of MDR is investigated, and the results reveal that the synergistic effect of the π–π stacked dual drugs promotes mitochondria‐dependent apoptosis.