Nano Drug Delivery System Based On Luteolin And Luteoloside

Luteolin and luteoloside have the broad application prospects because of their significant bioactivities. But their clinical applications are limited due to their water-insolubility, short half-life, fast metabolism and low bioavailability. In order to overcome these issues, potential drug delivery systems need to be formulated urgently. In recent years natural polymers and synthetic polymers are attractive materials to build drug system. So far drug delivery system based on luteolin or luteoloside is seldom reported to our knowledge. In this paper, using non-toxic, biocompatible and biodegradable polymer materials as carriers, luteolin and luteoloside as model drugs, several kinds of drug delivery system have been designed and constructed. The contents mainly include the following four parts: 1. The modified nanocrystalline cellulose for hydrophobic drug deliveryIvory nanocrystalline cellulose(NCC) was obtained with better dispersion and stability, high yield using the sulphuric acid hydrolysis method by dealing with microcrystalline cellulose under ultrasound inorder. NCC was firstly modified with a cationic surfactant cetyltrimethylammonium bromide(CTMAB) and CTMAB-coated NCC(CTMAB@NCC) was obtained. The morphology and structure of NCC and CTMAB@NCC were characterized by TEM and XRD. Obviously diameters of CTMAB@NCC are nearby 150 nm with relatively good dispersion. Stabilities of NCC and CTMAB@NCC were assayed by zeta potential. CTMAB@NCC was shown to bind the water-insoluble LUT and LUS by electrostatic force and hydrophobic force to form the conjugates CTMAB@NCC@LUT and CTMAB@NCC@LUS. In addition, CTMAB@NCC@LUT and CTMAB@NCC@LUS can form stable suspension solution. The loading content of LUT and LUS are 12.9±1.5 and 56.9±0.9 mg/g, respectively. Both the release of LUT and LUS of CTMAB@NCC@LUT and CTMAB@NCC@LUS were studied. It was found that the release could sustain over one day. For example, after 24 h, for LUT@CTMAB@NCC, at p H of 6.4, only 44 % of drug was released, whereas at p H 7.4, 57 % of the drug was released. For LUS@CTMAB@NCC, at p H 6.4, 57 % of drug was released, whereas at p H 7.4, 72 % of drug was released. The proposed method established a novel drug delivery system with potential to modulate the load and release of hydrophobic drugs.2. Engineering of luteolin and luteoloside into nanomicelles and drug release in vitro studiesThe biodegradable polymeric micelles formation of m PEG5K-PCL10 K, m PEG5K-PLGA10 K and m PEG5K-PDLLA10 K in aqueous medium were studied respectively by using pyrene fluorescence probe technique. LUT and LUS were successful loaded into the three copolymer micelles. The solubilization formulations of the three copolymer micelles were optimized by using response surface methodology(RSM). The size and shape of the drug-loaded copolymer micelles were determined by use of light scattering and TEM, respectively. The entrapment efficiency and drug loading were calculated. EE% and LC% of LUT loaded m PEG5K-PCL10 K, m PEG5K-PLGA10 K and m PEG5K-PDLLA10 K micelles are 65.1±5.1%, 51.64±3.1%, 46.02±2.4% and 3.75 ±1.2%, 3.28±1.3%, 2.35±0.6%, respectively. In the same way, EE% and LC% of LUS loaded the same copolymer micelles are 55.82±2.8%, 46.80±2.4%, 33.6±4.4% and 3.30±1.4%, 4.33±0.5%, 3.15±0.4%, respectively. The copolymer micelles have a certain solubilization promotion effect on LUT and LUS. Meanwhile, LUT(or LUS) loaded m PEG5K-PCL10 K and m PEG5K-PLGA10 K micelles were relatively stable. In addition, the drug-loaded copolymer micelles were released in vitro, showing the sustained release property. At p H 7.4, the maximum cumulative drug release percentage is 88%, however, at p H 6.4, no more than 35% of drug is released at 24 h. Our results indicate that m PEG5K-PCL10 K and m PEG5K-PLGA10 K micelles can become potential nanocarriers for LUT and LUS to overcome their poor solubility in water for further pharmaceutical and biological study. 3. Novel supramolecular hydrogels systems formed by m PEG-LUT conjugates for 5-fluorouracil drug delivery5-OH of LUT was firstly modified with different molecular weight methoxypoly(ethylene glycol)(m PEG), and novel structure of amphiphilic m PEG-LUT conjugates was obtained. Based on 3’, 4’ adjacent hydroxyl of m PEG-LUT, m PEG-LUT reacted with magnetic Fe3O4 particles, and novel structure of amphiphilic m PEG-LUT-Fe3O4 conjugates was obtained. All of conjugates can self-assemble stable polyrotaxanes supramolecular hydrogels through α-cyclodextrin in water. The morphology of supramolecular hydrogels was characterized by SEM. Results indicate that supramolecular hydrogels display typical porous structure and reversible thermosensitivity, which are suitable for drug delivery and tissue growth. In order to overcome short half-life of 5-fluorouracil(5-FU), the formed hydrogels were loaded with 5-FU to control its release. 5-FU is embedded into the supramolecular hydrogel three-dimensional network structure through the interaction between subject and object. When drug releasing it first broke the supramolecular network crosslinking, then diffused and penetrated the system. In vitro drug release study, the drug supramolecular hydrogels showed the sustained release property, and cumulative release time is more than 72 h. 4. Preliminary application research on Ag NPs loaded m PEG-LUTWe firstly synthesized m PEG-LUT-Ag NPs nanoparticles using m PEG-LUT as both the reducer and the stabilizer. The size, morphology and the absorption spectrum of m PEG-LUT-Ag NPs nanoparticles were characterized by SEM, TEM FT-IR and UV-Vis spectrophotometer, respectively. The proportions of m PEG-LUT combined onto the m PEG-LUT-Ag NPs is about 89.9%, and the content of siliver is 6.65%. The method of drilling hole was used to assay the antimicrobial activities of m PEG-LUT-Ag NPs nanoparticles against Staphlococcus aureus(SA), Extended spectrum β-Lactamases Staphlococcus aureus(ESBLs-SA), Escherichia Coli(EC) and Extended spectrum β-Lactamases Escherichia Coli(ESBLs-EC). Results showed that the m PEG-LUT-Ag NPs nanoparticles have good inhibition effect on both Gram negative and positive bacteria, and the inhibition on Gram negative bacteria is better than that on positive bacteria. We also used MTT to study the cytotoxicity of m PEG-LUT-Ag NPs nanoparticles on human breast cancer cell MCF-7 and hepatoma carcinoma cell Hep G2. The results demonstrated that m PEG-LUT-Ag NPs nanoparticles have toxicity on both MCF-7 and Hep G2 cells with dosage dependence, and the toxic effects on MCF-7 cells is stronger than that on HepG2 cells.