| In this paper, Multi-shape like spherical, ellipsoidal, disklike, and rodlike inorganic/organic hybrid particles are fabricated in droplet microfluidics. Instead of photo-polymerization commonly used in the literature, the diversity in particle configuration is realized via the fast hydrolysis of organometallic compound.In general case,inorganic/organic hybrid particles fabricated by directly incorporating inorganic components in the dispersed phase in microfluidic,while our hybrid particles are synthesized in situ because the inorganic component is one of the hydrolysis products, which avoids the agglomeration or precipitation of inorganic components and thus ensures the particle homogeneity. In this paper, we demonstrate the new strategy by using hybrid particle containing poly(lactide-co-glycolide)(PLGA) and Ti O2 as a model material, among which Ti O2 is originated from hydrolysis of n-butyl titanate(TBT). The PLGA/Ti O2 hybrid particles are homogeneity.The generation of n-butanol, as the other hydrolysis product, induces the interfacial instabilities of emulsion droplets and triggers the convolution of particle surface. Moreover, due to the presence of hyper-dispersed n-butanol caused by localized TBT hydrolysis in PLGA matrix, porous internal structure can be formed in PLGA/Ti O2 particle(when the particles were freeze-dried). To investigate the mechanism about surface wrinkles and inner porous structure of PLGA/Ti O2 hybrid particles, make two explanations about the wrinkles on PLGA/Ti O2 hybrid particles surface through the test of contact angle and observation on the particles surface firstly(Affected by the two mechanisms). One is the interfacial instabilities of emulsion dropletsinduced by n-butanol as the hydrolysis product of TBT, the other is elastic-driven wrinkling of the solid film generated on PLGA/TBT droplet surface through TBT hydrolysis.Second, by the sliced SEM figures of different particles, the porous hybrid particles that the pore sizes are between 0.4 and 1.2 um were fabricated without adding any porogen. The mechanism of porous internal structure in PLGA/Ti O2 particles:When water diffuses across the PLGA matrix to the small TBT droplets, hydrolysis reaction occurs and generates hyper-dispersed n-butanol. Once the PLGA/Ti O2 particles are freeze-dried, the hyper-dispersed n-butanol is volatilized, leaving uniform pore structure.Size, shape and surface morphology of carriers are important to the drug release. In this paper, spherical particles with different surface morphology and chemical component were fabricated using PDMS microfluidic. As TTIP is hydrolysis slower than TBT, we synthesized the PLGA/Ti O2 hybrid particles which are uniform size and controllable surface morphology based on the PDMS microfluidic. At the same time, we choose the tanshinone IIA as the special drug and synthesize different carriers. The results of the drug releasing of in vitro PBS buffer research shows that the encapsulation efficiency of PLGA carriers, PLGA&Nano Ti O2 carriers and PLGA/Ti O2 carriers is 84.9%,81.7% and 83.1% meanwhile the cumulative release rate is 6.6%,8.4% and 13.6% in 430 h, respectively. Besides, all the carriers are controlled release. |
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