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Starting from the concept of research-based teaching, this paper puts forward the cultivation of innovative consciousness and innovative ability in the physics experiments. The cultivation mainly depends on the flowing three principles ; based on the problem, based on the research of learning and training, and based on the project. The goal is to cultivate and gradually improve the students' scientific experiment quality and innovative ability, The goal can meet the needs of different levels talents, build a series of physical experiment courses, and match the seven teaching experiment module. The guiding ideology of the entire series curriculum system construction and experimental teaching mode is; Attaching great importance to the foundation, arousing interest, oil characteristics, and guiding the innovation. The teaching concept is to permeate scientific research element in seven experiment teaching module process, embody the oil characteristics, focus on the physical experiment courses. The paper successful experience in topic selection and implementation in physics innovative experimental courses. The research achievements are widely expanded and applied in our series of physical experiment courses, and good effects are obtained. [ABSTRACT FROM AUTHOR]

Layered double hydroxide (LDH) has attracted considerable attention as a drug carrier. However, because of its poor in vivo behavior, polyethylene glycolylated (PEGylated) phospholipid must be used as a coformer to produce self-assembled core-shell nanoparticles. In the present study, we prepared a PEGylated phospholipid-coated LDH (PLDH) (PEG-PLDH) delivery system. The PEG-PLDH nanoparticles had an average size of 133.2 nm. Their core-shell structure was confirmed by transmission electron microscopy and X-ray photoelectron spectroscopy. In vitro liposome-cell-association and cytotoxicity experiments demonstrated its ability to be internalized by cells. In vivo studies showed that PEGylated phospholipid membranes greatly reduced the blood clearance rate of LDH nanoparticles. PEG-PLDH nanoparticles demonstrated a good control of tumor growth and increased the survival rate of mice. These results suggest that PEG-PLDH nanoparticles can be a useful drug delivery system for cancer therapy.

For the purposes of obtaining a hepatocyte-selective drug delivery system, a novel tetravalent galactosylated diethylenetriaminepentaacetic acid-distearoyl phosphatidylethanolamine (4Gal-DTPA-DSPE) was synthesized. The chemical structure of 4Gal-DTPA-DSPE was confirmed by proton nuclear magnetic resonance and mass spectrometry. The four galactose-modified liposomes (4Gal-liposomes) were prepared by thin-film hydration method, then doxorubicin (DOX) was encapsulated into liposomes using an ammonium sulfate gradient loading method. The liposomal formulations with 4Gal-DTPA-DSPE were characterized by laser confocal scanning microscopy and flow cytometry analysis, and the results demonstrated that the 4Gal-liposomes facilitated the intracellular uptake of DOX into HepG2 cells via asialoglycoprotein receptor-mediated endocytosis. Cytotoxicity assay showed that the cell proliferation inhibition effect of 4Gal-liposomes was higher than that of the conventional liposomes without the galactose. Additionally, pharmacokinetic experiments in rats revealed that the 4Gal-liposomes displayed slower clearance from the systemic circulation compared with conventional liposomes. The organ distributions in mice and the study on frozen sections of liver implied that the 4Gal-liposomes enhanced the intracellular uptake of DOX into hepatocytes and prolonged the circulation. Taken together, these results indicate that liposomes containing 4Gal-DTPA-DSPE have great potential as drug delivery carriers for hepatocyte-selective targeting.

Surface modification of nanocarriers with amphiphilic polymer polyethylene glycol (PEG), known as PEGylation, is regarded as a major breakthrough in the application of nanocarriers. However, PEGylated nanocarriers (including liposomes and polymeric nanoparticles) induce what is referred to as the "accelerated blood clearance (ABC) phenomenon" upon repeated injection and consequently they lose their sustained circulation characteristics. Despite this, the present authors are not aware of any reports of accelerated clearance due to repeated injection for PEGylated solid lipid nanoparticles (SLNs), another promising nanocarrier. This study investigated the pharmacokinetics of PEGylated SLNs upon repeated administration in mice; moreover, the impact of circulation time on the induction of the ABC phenomenon was studied in beagles for the first time. The ABC index, selected as the ratio of the area under the concentration-time curve from time 0 to the last measured concentration of a second injection to that of the first injection, was used to evaluate the extent of this phenomenon. Results showed that the PEGylated SLNs exhibited accelerated clearance from systemic circulation upon repeated injection, both in mice and in beagles, and the ratio for the different time intervals, which showed that the ABC index exhibited significant difference within 30 minutes following the second injection, was good enough to evaluate the magnitude of ABC. This ABC index indicated that the 10 mol% PEG SLNs with a suitable prolonged circulation time induced the most marked ABC phenomenon in this research. This study demonstrated that, like PEGylated nanocarriers such as liposomes and polymeric nanoparticles, PEGylated SLNs induced the ABC phenomenon upon repeated injection--the beagle was a valuable experimental animal for this research. Furthermore, the authors considered that a relatively extended circulation time of the initial dose may be the underlying major factor determining the induction of the ABC phenomenon.