Au-nanocluster-loaded human serum albumin nanoparticles with enhanced cellular uptake for fluorescent imaging

Protein-directed fluorescent Au nanoclusters have been widely studied owing to their potential applications in sensing,imaging,and drug and gene delivery.However,the use of nanoclusters in drug delivery is limited by low cellular uptake.In this study,human serum albumin-directed Au nanoclusters served as building blocks to obtain protein nanoparticles by desolvation.The nanoparticles had a decent quantum yield(QY),high colloidal stability and low cytotoxicity,and they could be readily conjugated with biological molecules.The cellular uptake of the Au nanoclusters and nanocluster-loaded protein nanoparticles were studied by confocal fluorescence microscopy.Agglomeration of the protein-directed Au nanoclusters into 50–150-nm nanoparticles dramatically increased the cellular uptake.

Synthesis of Zinc Oxide Nanoparticles with Good Photocatalytic Activities under Stabilization of Bovine Serum Albumin

Zinc oxide nanoparticles were synthesized using bovine serum albumin as stabilizers through a facile one-pot strategy in aqueous media. The morphology and crystal phase of the zinc oxide nanoparticles were determined by transmission electron microscopy, X-ray diffractograms, and Fourier transform infrared spectroscopy. The synthesized ZnO nanoparticles exhibited strong absorption and photoluminescence properties in the visible wavelength region based on the fluorescence and UV-visible spectroscopy. Based on the results, the zinc oxide nanoparticles could effectively degrade the organic dyes through the mediation of the hydroxyl radical under visible light irradiation. Furthermore, the zinc oxide nanoparticles show good recycling stability during the photocatalytic experiments. These results suggested that the as-prepared zinc oxide nanoparticles might be used as a potential photocatalyst to efficiently treat the organic pollutants.

Hematological and pathological toxicity of anti-HER2/neu peptide mimetic modified paclitaxel bovine serum albumin nanoparticles

Nanoparticles have been widely applied in diagnosis and therapy due to the high loading of insoluble drug, increased target accumulation and interaction with biological tissues. Recently, severe side effects of nanoparticles have been reported, but the underlying mechanism remains largely unknown. In our study, we aim to understand the safety of paclitaxel （PTX） loaded bovine albumin nanoparticles （BNPs） and active targeted PTX loaded BNPs to normal vital organ or tissue in vivo. The anti-human epidermal growth factor receptor 2 （HER2/neu） peptide mimetic （AHNP） was covalent bound to surface of BNPs （AHNP-BNPs） to exert selected delivery to HER2＋ cells. In HER2＋ tumor xenographs, saline （control）, PTX traditional formula （medium of Cremophor EL-ethanol）, BNPs, and AHNP-BNPs were administrated to evaluate the toxicity. There is no severe neutropenia or anemia with treatment of BNPs and AHNP-BNPs compared with traditional PTX injection. We also evaluated their damage on normal organs, including liver, kidney, spleen, lung and heart to fully estimate the safety of AHNP-BNPs and BNPs delivery systems. We observed similar toxicity in liver and lung in mice treated with BNPs or PTX injection, but decreased liver damage in mice treated with AHNP-BNPs. Further studies are rcouired to confirm our conclusion.

The preparation and characterization of folate-conjugated human serum albumin magnetic cisplatin nanoparticles

Objective： Nanoparticles are becoming an important method of targeted drug delivery. To evaluate the importance of folate-conjugated human serum albumin （HSA） magnetic nanoparticles （Folate-CDDP/HSA MNP）, we prepared drug-loaded Folate-CDDP/HSA MNPs and characterized their features. Methods： First, folate was conjugated with HSA under the effect of a condensing agent, and the conjugating rate was evaluated by a colorimetric method using 2, 4, 6 - trinitrobenzene sulfonic acid. Second, under N., gas, Fe：~O1 magnetic nanomaterials were prepared and characterized by using transmission electron microscopy （TEM）, SEM-EDS and X-ray diffraction （XRD）. Finally, Folate-CDDP/HSA MNP was prepared by using a solvent evaporation technique. TEM was used to observe particle morphology. The particle size and distribution of the prepared complexes were determined by a Laser particle size analyzer. Drug loading volume and drug release were investigated by a high performance liquid chromatography method （HPLC） in vitro. Results： We successfully prepared folate-conjugated HSA and its conjugating rate was 27.26 μg/mg. Under TEM, Fe2O4 magnetic nanoparticles were highly electron density and had an even size distribution in the range of 10-20 nm. It was confirmed by SEM-EDS and XRD that Fe304 magnetic nanoparticles had been successfully prepared. Under TEM, drug-loaded magnetic nanoparticles were observed, which had a round shape, similar uniform size and smooth surface. Their average size was 79 nm which was determined by laser scattering, and they exhibited magnetic responsiveness. Encapsulation efficiency was 89.75% and effective drug loading was calculated to be 15.25%. The release results in vitro showed that the half release time （ta/2） of cisplatin in cisplatin Solution and Folate-CDDP/HSA MNP was 65 min and 24 h respectively, which indicated that microspheres had an obvious effect of sustained-release. Conclusion： Folate-CDDP/HSA MNPs were prepared successfully. The preparation process and related characteristics data provided a foundation for further study, including the mechanism of the nanoparticles distribution in vivo and their intake by tumor cells.

A stability-indicating high performance liquid chromatography method to determine apocynin in nanoparticles

In this study, we developed and validated a fast, specific, sensitive, precise and stability-indicating high performance liquid chromatography（HPLC） method to determine the drug apocynin in bovine serum albumin（BSA） nanoparticles. Chromatographic analyses were performed on an RP C18 column and using a photodiode array detector at a wavelength of 276 nm. Mobile phase consisted of a mixture of acetonitrile and 1% acetic acid（60：40, v/v）, and it was eluted isocratically at a flow rate of 0.8 mL/min. The retention time of apocynin chromatographic peak was 1.65 min. The method was linear, precise, accurate and specific in the range of 5–100 μg/mL. The intra-and inter-day precisions presented relative standard deviation（RSD） values lower than 2%. The method was robust regarding changes in mobile phase proportion, but not for flow rate. Limits of detection and quantitation were 78 ng/mL and 238 ng/mL, respectively. Apocynin was exposed to acid and alkali hydrolysis, oxidation and visible light. The drug suffered mild degradation under acid and oxidation conditions and great degradation under alkali conditions. Light exposure did not degrade the drug. The method was successfully applied to determine the encapsulation efficiency of apocynin in BSA nanoparticles.

Promoting chondrogenesis by targeted delivery to the degenerating cartilage in early treatment of osteoarthritis

Osteoarthritis(OA)is a highly incident total joint degenerative disease with cartilage degeneration as the primary pathogenesis.The cartilage matrix is mainly composed of collagen,a matrix protein with a hallmark triplehelix structure,which unfolds with collagen degradation on the cartilage surface.A collagen hybridizing peptide(CHP)is a synthetic peptide that binds the denatured collagen triple helix,conferring a potential diseasetargeting possibility for early-stage OA.Here,we constructed an albumin nanoparticle(An)conjugated with CHP,loaded with a chondrogenesis-promoting small molecule drug,kartogenin(KGN).The CHP-KGN-An particle exhibited sustained release of KGN in vitro and prolonged in vivo retention selectively within the degenerated cartilage in the knee joints of model mice with early-stage OA.Compared to treatment with KGN alone,CHP-KGN-An robustly attenuated cartilage degradation,synovitis,osteophyte formation,and subchondral bone sclerosis in OA model mice and exhibited a more prominent effect on physical activity improvement and pain alleviation.Our study showcases that targeting the degenerated cartilage by collagen hybridization can remarkably promote the efficacy of small molecule drugs and may provide a novel delivery strategy for earlystage OA therapeutics.