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Three-dimensional (3D) printing,a type of rapid prototyping technology,is based on a digital model file and prints layer-by-layer using adhesive materials,such as powdered metal or plastic.3D printing has attracted much attention in the pharmaceutical field because of the various advantages,such as simple operation,good flexibility,high repeatability,wide adaptability,and more importantly,customized service.Currently,it is used in formulations of immediate release,sustained release,implants,etc.Recently,the integration of medical devices and drugs with 3D printing has been gaining popularity.This review not only summarizes the latest progress in techniques,materials,and pharmaceutical dosage forms used in drug delivery system with 3D printing,but also analyzes its advantages and limitations,with the hope of providing reference for the development and application of 3D printing technology in drug delivery.This novel drug delivery system will bring new vitality to individualized medication.
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The contents of terrestrosin D and hecogenin from Tribuli Fructus were determined before and after stir-frying. The results showed that the content of terrestrosin D was decreased significantly,and the content of hecogenin was increased significantly after such processing. In order to verify the inference that terrestrosin D was converted to hecogenin by stir-frying,the quantitative variation rules of terrestrosin D and hecogenin were studied by simulated processing technology,and the simulated processing product of terrestrosin D was qualitatively characterized by ultra performance liquid chromatography/time of flight mass spectrometry( UPLC-TOF/MS) to clarify its transformation process during stir-frying. The results showed that the content of terrestrosin D was decreased significantly at first and then a platform stage appeared with the prolongation of processing time at a certain temperature. Raising the stir-frying temperature could further decrease the content of terrestrosin D and delay the time that the platform stage appeared. When the processing was simulated at higher temperatures( 220 ℃ and 240 ℃),the content of hecogenin was increased gradually with the increase of processing temperature and the prolongation of processing time. In the process of stir-frying,the deglycosylation reaction of terrestrosin D to hecogenin was not completed in one step. The deglycosylation reaction occurred first at the end of the sugar chain,and then other glycosyl units in the sugar chain were sequentially removed from the outside to the inside to finally form the hecogenin. This study provides a basis for further revealing the detoxification mechanism of stir-fried Tribuli Fructus.
Subject(s)
Chromatography, Liquid , Fruit , Chemistry , Hot Temperature , Phytochemicals , Sapogenins , Tandem Mass Spectrometry , Zygophyllaceae , ChemistryABSTRACT
AIM To determine effective components of Ampelopsis grossedentata (Hand.-Mazz.) W.T.Wang under different breeding modes and to analyze the antioxidant enzyme activities.METHODS Single factor and orthogonal tests were adopted in screening the optimal extraction process of antioxidant enzymes and analyzing antioxidant enzyme activities of A.grossedentata under common cutting,two-phase cutting and tissue culture.Solvent extraction method was adopted in extracting the effective components of three breeding modes in stem leaves of A.grossedentata,whose contents were determined.RESULTS In three breeding modes,the content of polysaccharides in tissue culture seedling was the highest,while the contents of flavonoids and polyphenols in the two stage cutting seedlings were the highest.The optimal extraction process of antioxidant enzymes was determined to be 6.0 for pH,20 ℃ for processing temperature and 20 min for processing time.Antioxidant enzyme activities were in sequence of two stage cutting seedlings ＞ common cutting seedling ＞ tissue culture seedling.CONCLUSION Considering the contents of effective components and antioxidant enzyme activities,two stage cutting method is the best among 3 breeding modes.
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ABSTRACT:Objective To observe the structural changes of dentin irradiated with Nd:YAG laser under dif-ferent parameters and the changes of calcium-phosphorus ration,and evaluate the optimal parameters of Nd:YAG laser in treating dentin hypersensitivity (DH).Methods The model of dentin hypersensitivity was established by acid etching method.Samples were irradiated with Nd:YAG laser under different parameters.The morphological alterations of the dentin surfaces and Ca-P ratio were examined with scanning electron microscopy (SEM)combined with energy dispersive X-ray microanalysis.Results Compared with those in the control group,dentinal tubules could be blocked partially or totally with no cracks in A-C (30 mj,5 Hz),(30 mj,10 Hz)and (50 mj,5 Hz)groups. Dentinal tubules could be entirely blocked but with cracks in D (50 mj,10 Hz)and E (80 mj,5 Hz)groups.Dentin was carbonized in F (80 mj,10 Hz)group.Compared with that in the control group,Ca-P ratio was decreased sig-nificantly (P <0.05).Conclusion The suitable energy parameter of Nd:YAG laser in treating dentin hypersensi-tivity is (30 mj,10 Hz)and (50 mj,5 Hz).