ABSTRACT
Objective:To prepare the sustained release system of icariin(ICA)@ gelatin nanoparticles (GNPs)-polyactic-co-glycolic acid(PLGA)(ICA @ GNPs-PLGA), and to optimize the conditions. Methods:ICA@GNPs-PLGA sustained release system was prepared using two-step desolvation method and S/O/W emulsion solvent-evaporation technique.The effects of different conditions,such as the PLGA:GNPs mass ratio and the total quality of ICA added on the entrapment efficiency(EE)of ICA@GNPs-PLGA composite microspheres were detected to optimize the preparation process. The surface morphology of GNPs and ICA@GNPs-PLGA composite microspheres were observed by SEM.The EE and the release results of ICA@GNPs-PLGA in the sample were determined with HPLC.Results:The prepared composite microspheres and nanocomplex were were white powder.The SEM results showed that the composite microspheres and nanocomplexs were spherical,the surfaces were smoothy,and the particle size distribution range was 4-12 μm and 150-200 nm,respectively,relatively uniform.At a GNPs mass fraction of 6 mg,the critical concentration of PLGA in DCM ranged within 0.5%-1.0%.At a GNPs mass fraction of 12 mg,the critical concentration of PLGA in DCM ranged within 1.0%-2.0%.However,at a critical PLGA mass fraction lower than 0.25%,no fully formed composite microspheres were observed.Within the critical concentration,the average EE of ICA@GNPs-PLGA microspheres was higher than(62.00±1.25)%.In addition,the EE of ICA in the microspheres was negatively correlated with the quality of ICA added.The accumulative release rate was less than in 24 h and it was 65.21% in 40 d.Conclusion:The ICA@GNPs-PLGA microspheres with homogeneous particle size distribution,high EE,low initial burst and without agglomeration can be acquired under the optimized conditions.
ABSTRACT
Objective: To prepare the sustained release system of icariin (ICA) @ gelatin nanoparticles (GNPs)-polyactic-co-glycolic acid (PLGA) (ICA @ GNPs-PLGA), and to optimize the conditions. Methods: ICA@GNPs-PLGA sustained release system was prepared using two-step desolvation method and S/O/W emulsion solvent-evaporation technique. The effects of different conditions, such as the PLGA: GNPs mass ratio and the total quality of ICA added on the entrapment efficiency (EE) of ICA® GNPs-PLGA composite microspheres were detected to optimize the preparation process. The surface morphology of GNPs and ICA @ GNPs-PLGA composite microspheres were observed by SEM. The EE and the release results of ICA@GNPs-PLGA in the sample were determined with HPLC Results: The prepared composite microspheres and nanocomplex were were white powder. The SEM results showed that the composite microspheres and nanocomplexs were spherical, the surfaces were smoothy, and the particle size distribution range was 4-12 μm and 150-200 nm, respectively, relatively uniform At a GNPs mass fraction of 6 mg, the critical concentration of PLGA in DCM ranged within 0.5%-1.0%. At a GNPs mass fraction of 12 mg, the critical concentration of PLGA in DCM ranged within 1.0%-2.0%. However, at a critical PLGA mass fraction lower than 0.25%, no fully formed composite microspheres were observed. Within the critical concentration, the average EE of ICA@ GNPs-PLGA microspheres was higher than (62.00 ± 1.25)%. In addition, the EE of ICA in the microspheres was negatively correlated with the quality of ICA added. The accumulative release rate was less than in 24 h and it was 65.21% in 40 d. Conclusion: The ICA@GNPs-PLGA microspheres with homogeneous particle size distribution, high EE, low initial burst and without agglomeration can be acquired under the optimized conditions.
ABSTRACT
OBJECTIVE:To study the percutaneous properties of Man-PEI25k nanocomplex under the treatment of microneedles. METHODS:Using fluorescent dye water-soluble carboxyl CdSe/ZnS quantum dot (QD) as model drug, Man-PEI25k/QD and Man-PEI25k/QD nanocomplex with different grafting rates(1∶3,1∶6)were formed through electrostatic adherence with PEI25k and Man-PEI25k. The distribution of QD in the active epidermal layer and dermis of skin were observed by confocal microscopy after the treatment of microneedles,using free QD as control. The accumulative retention amounts of QD in the active epidermal layer and dermis of skin were determined by fluorescence spectrophotometer after PEI25k/QD and Man-PEI25k/QD nanocomplex treated with mi-croneedles. RESULTS:The amounts of Man-PEI25k/QD nanocomplex in active epidermal layer and dermis were significantly higher than that of PEI25k/QD nanocomplex under the treatment of microneedles in vivo;the amounts of Man-PEI25k/QD (1∶6) nanocom-plex in active epidermal layer and dermis of skin were significantly higher than that of Man-PEI25k/QD(1∶3)nanocomplex. In in vi-tro transdermal diffusion experiments,microneedles could increase the retention amounts of nanocomplex in active epidermal layer and dermis of skin significantly. The retention amounts of Man-PEI25k/QD nanocomplex in active epidermal layer were increased by 2 times of that of PEI25k/QD under the treatment of microneedles after 48 h;at the same time,in the dermis that was increased by 1.5 times,with statistical significance (P<0.01). CONCLUSIONS:Microneedles can improve the percutaneous properties of Man-PEI25k nanocomplex in active epidermal layer.
ABSTRACT
Objective To use polyamidoamine dendrimers (PAMAM) loaded with sh miR 34a for constructing PAMAM/ sh-miR-34a nanocomplexes and to observe its inhibitory effect on the proliferation, invasion and metastasis of malignant melanoma A375 cells. Methods Particle size analyzer was used to investigate the potential and size of the constructed PAMAM/sh-miR-34a nanocomplex, and sh-miR-34a enrichment capability was determined by gel electrophoresis assay. The intracellular uptake of PAMAM/sh-miR-34a by A375 cells was investigated using sh-miR-34a labeled by rhodamine. CCK8 method was used to determine the inhibitory effect of the nanocomplex against A375 cell proliferation. Transwell assay was used to determine the inhibition effect of nanocomplex against A375 cell migration and invasion. Western blotting analysis was used to examine the inhibitory effect of PAMAM/sh-miR-34a on the protein expression of pAkt, pRb, and pERKl/2 in A375 cells. Results PAMAM loaded with sh-miR-34a could form stable nanocomplexes. The intracellular uptake of PAMAM/sh-miR-34a by A375 cells was the highest when N/P = 20 (P<0. 05). PAMAM effectively mediated sh-miR-34a entry into A375 cells, inhibiting the cell proliferation- invasion and metastasis and blocking the protein expression of pAkt, pRb. and pERKl/2 in A375 cells. Conclusion PAMAM can enwrap sh-miR-34a and inhibit malignant melanoma A375 cells