Balancing Microthrombosis and Inflammation via Injectable Protein Hydrogel for Inflammatory Bowel Disease.

Emerging evidence indicates that a vicious cycle between inflammation and microthrombosis catalyzes the pathogenesis of inflammatory bowel disease (IBD). Over-stimulated inflammation triggers a coagulation cascade and leads to microthrombosis, which further complicates the injury through tissue hypoxia and ischemia. Herein, an injectable protein hydrogel with anti-thrombosis and anti-inflammation competency is developed to impede this cycle, cross-linked by silver ion mediated metal-ligand coordination and electronic interaction with sulfhydryl functionalized bovine serum albumin and heparin, respectively. The ex vivo experiments show that the hydrogel, HEP-Ag-BSA, exhibits excellent self-healing ability, injectability, biocompatibility, and sustained drug release. HEP-Ag-BSA also demonstrates anti-coagulation and anti-inflammation abilities via coagulation analysis and lipopolysaccharide stimulation assay. The in vivo imaging confirms the longer retention time of HEP-Ag-BSA at inflammatory sites than in normal mucosa owing to electrostatic interactions. The in vivo study applying a mouse model with colitis also reveals that HEP-Ag-BSA can robustly inhibit inflammatory microthrombosis with reduced bleeding risk. This versatile protein hydrogel platform can definitively hinder the "inflammation and microthrombosis" cycle, providing a novel integrated approach against IBD.

Clickable Albumin Nanoparticles for Pretargeted Drug Delivery toward PD-L1 Overexpressing Tumors in Combination Immunotherapy.

We present a simple methodology to design a pretargeted drug delivery system, based on clickable anti-programmed death ligand 1 (anti-PD-L1) antibodies (Abs) and clickable bovine serum albumin (BSA) nanoparticles (NPs). Pretargeted drug delivery is based on the decoupling of a targeting moiety and a drug-delivering vector which can then react in vivo after separate injections. This may be key to achieve active targeting of drug-delivering NPs toward cancerous tissue. In pretargeted approaches, drug-delivering NPs were observed to accumulate in a higher amount in the targeted tissue due to shielding-related enhanced blood circulation and size-related enhanced tissue penetration. In this work, BSA NPs were produced using the solvent precipitation methodology that renders colloidally stable NPs, which were subsequently functionalized with a clickable moiety based on chlorosydnone (Cl-Syd). Those reactive groups are able to specifically react with dibenzocyclooctyne (DBCO) groups in a click-type fashion, reaching second-order reaction rate constants as high as 1.9 M-1·s-1, which makes this reaction highly suitable for in vivo applications. The presence of reactive Cl-Syd was demonstrated by reacting the functionalized NPs with a DBCO-modified sulfo-cyanine-5 dye. With this reaction, it was possible to infer the number of reactive moieties per NPs. Finally, and with the aim of demonstrating the suitability of this system to be used in pretargeted strategies, functionalized fluorescent NPs were used to label H358 cells with a clickable anti-PD-L1 Ab, applying the reaction between Cl-Syd and DBCO as corresponding clickable groups. The results of these experiments demonstrate the bio-orthogonality of the system to perform the reaction in vitro, in a period as short as 15 min.

"Sustained irrigation" effect enhanced the accumulation and retention of ultra-long circulating nanoparticles in tumor.

The development of ultra-long circulating nanodrug delivery systems have showed distinct advantage in maintaining the long-lasting tumor retention. Although the relationship between extended tumor retention and ultra-long plasma half-life was apparent, there was still a lack of experimental evidence to reveal the enhancement mechanism. Herein, we proposed a concept of "Sustained Irrigation" effect ("SI" effect) to elucidate that it was through sustained blood irrigation that the ultra-long circulating nanoparticles achieved long-lasting tumor retention. Besides, in order to intuitively verify the "SI" effect, we developed an "ON-OFF-ON" fluorescence switch technology. The ultra-long circulating delivery nanoparticle was constructed by encapsulating the protein with hydrophilic polymer shell. Nanoparticles with ultra-long plasma half-life (t1/2>40 h) fabricated by this method were employed as models for demonstrating the "SI" effect. The recovery of Cy5.5 fluorescence after the laser quenching meant the "fresh" Cy5.5-labeled nanoparticles were entering tumor, which confirmed the ultra-long circulating nanoparticles in blood could sustainedly irrigate to tumor. Our finding revealed the key mechanism by which ultra-long circulating NDDSs enhanced the tumor accumulation and retention, and provided experimental support for the development of ultra-long circulating delivery system in clinic.

Treatment of spinal tuberculosis in rabbits using bovine serum albumin nanoparticles loaded with isoniazid and rifampicin.

OBJECTIVE: To evaluate the clinical efficacy of bovine serum albumin nanoparticles loaded with isoniazid and rifampicin (INH-RFP-BSA-NPs) in the treatment of spinal tuberculosis in rabbits. METHODS: 35 spinal tuberculosis rabbit models were grouped into three groups, including 14 in group A and group B respectively and 7 in group C.All rabbits in group A were treated by INH-RFP-BSA-NPs's injection and in group B were treated with classic dosage form of INH and RFP, while in group C normal saline was given as the blank control. After intervention, the body weighing and CT scan, as well as concentration's measurement of INH and RFP in blood and tissues, were performed in all rabbits at the time of the 6thweek and 12th week, respectively. RESULTS: In group A, rabbits' weight increased by 0.44 kg and 0.27 kg within 6 weeks and 12 weeks' treatment respectively. The bactericidal concentrations of 1.64 µg•g-1 for INH and 21.36 µg•g-1 for RFP were measured in focus vertebral body 6 weeks post-injection and six weeks later the concentrations of INH and RFP in vertebral body still maintained at the level of 1.96 µg•g-1 and 22.35 µg•g-1respectively. After 12 weeks therapy, CT-scanned showed all the necrotic tissue was replaced by normal bone tissue. In group B, all rabbits had no significant increment of body weight and 4 rabbits had paralysis of hind leg. The concentrations of INH and RFP in vertebral body and focus were much lower than group A. CT-scanned showed the focus vertebral body was only partially repaired after 12 weeks' therapy. CONCLUSION: The INH-RFP-BSA-NPs has the characteristics of sustained release in vivo and target biodistribution in focus vertebral body. Its therapeutic effect in rabbit spinal tuberculosis is much better than common INH and RFP.

Combined Application of Prototype Ultrasound and BSA-Loaded PLGA Particles for Protein Delivery.

PURPOSE: To develop an in vitro culture system for tissue engineering to mimic the in vivo environment and evaluate the applicability of ultrasound and PLGA particle system. METHODS: For tissue engineering, large molecules such as growth factors for cell differentiation should be supplied in a controlled manner into the culture system, and the in vivo microenvironment need to be reproduced in the system for the regulation of cellular function. In this study, portable prototype ultrasound with low intensity was devised and tested for protein release from bovine serum albumin (BSA)-loaded poly(lactic-co-glycolic acid) (PLGA) particles. RESULTS: BSA-loaded PLGA particles were prepared using various types of PLGA reagents and their physicochemical properties were characterized including particle size, shape, or aqueous wetting profiles. The BSA-loaded formulation showed nano-ranged size distribution with optimal physical stability during storage period, and protein release behaviors in a controlled manner. Notably, the application of prototype ultrasound with low intensity influenced protein release patterns in the culture system containing the BSA-loaded PLGA formulation. The results revealed that the portable ultrasound set controlled by the computer could contribute for the protein delivery in the culture medium. CONCLUSIONS: This study suggests that combined application with ultrasound and protein-loaded PLGA encapsulation system could be utilized to improve culture system for tissue engineering or cell regeneration therapy.

Evans blue dye as an indicator of albumin permeability across a brain endothelial cell monolayer in vitro.

An increase in the brain endothelial (BEnd) cell permeability of blood albumin is often seen as an early sign of blood-brain barrier (BBB) disruption and can precede increases in the BEnd permeability of small molecules and other plasma proteins in the course of brain disease. Therefore, Evans blue dye (EBD), an albumin-binding fluorescent tracer that is simple to detect and quantify, has been widely utilized for studying BEnd permeability during BBB disruption. Here, we investigated whether EBD is a suitable indicator of albumin permeability across mouse BEnd cell monolayers, alone or cocultured with mouse cortical astrocytes, in an in-vitro permeability assay; given the strong affinity of EBD for albumin, we further asked whether EBD can affect albumin permeability and vice versa. Albumin and EBD readily crossed membrane cell culture inserts with pore diameters of no less than 1 µm in the absence of a cellular barrier, and their permeability was substantially reduced when the membranes were overlaid with a monolayer of BEnd cells. In line with albumin binding, the BEnd permeability of EBD was substantially reduced by the presence of albumin. While EBD at an EBD-to-albumin ratio similar to those typically used in in vivo BBB experiments had little effect on the BEnd permeability of albumin, a much higher concentration of EBD augmented the BEnd permeability of albumin. In conclusion, we investigated the use of EBD as an indicator of albumin permeability in vitro, explored some of its drawbacks and further demonstrated that EBD at the concentration used in vivo does not affect albumin permeability.

Chitosan-bovine serum albumin-Carbopol 940 nanogels for mupirocin dermal delivery: ex-vivo permeation and evaluation of cellular binding capacity via radiolabeling.

The goal of this study was to develop and examine the nanogel-based topical delivery system of mupirocin. Nanogels were prepared with chitosan and bovine serum albumin by ionic gelation and Carbopol 940 was added to improve the gelling/adhesive properties. Detailed characterization studies were performed and the cellular binding capacity of radiolabeled nanogels was investigated on CCD-1070Sk cell lines. Results indicate the successful formation of nanogels with particle size and zeta potential ranged between 341.920-603.320 nm and 13.120-24.300 mV, respectively. The mechanical and rheological studies proved pseudoplastic and strong elastic gel behavior (G' > G''). Mupirocin was successfully entrapped into nanogels with a ratio of more than 95% and the loaded drug was slowly released up to 93.89 ± 3.07% within 24 h. The ex vivo penetration and permeation percentages of mupirocin were very low (1.172 ± 0.202% and 0.161 ± 0.136%) indicating the suitability of nanogels for dermal use against superficial skin infections. The microbiological studies pointed out the effectiveness of nanogels against Staphylococcus aureus strains. Nanogels did not show toxicity signs and the cell binding capacity of radiolabeled formulations was found to be higher than [99mTc]NaTcO4 to CCD-1070Sk cell line. Overall, mupirocin nanogels might be considered as a potential and safe topical treatment option for bacterial skin infections.

Selenium nanoparticles inhibit the formation of atherosclerosis in apolipoprotein E deficient mice by alleviating hyperlipidemia and oxidative stress.

Atherosclerosis can cause severe cardiovascular diseases, which is the most common cause of death in the world. It's of great significance to study the prevention and treatment of atherosclerosis. Selenium nanoparticles (SeNPs) has drawn more and more attention due to high biological activity, high bioavailability, strong antioxidant capacity and low toxicity, exhibiting great potential in biomedical application. Thus, this study aimed at explore the anti-atherosclerotic effect of two kinds of SeNPs, bovine serum albumin (BSA) surface-decorated SeNPs and chitosan (CS) surface-decorated SeNPs (CS-SeNPs), in apolipoprotein E deficient (ApoE-/-) mice fed with a high-cholesterol and high-fat diet, and the possible mechanisms. The results demonstrated that both BSA-SeNPs (25, 50 and 100 µg Se/kg body weight/day) and CS-SeNPs (50 µg Se/kg body weight/day) could reduce atherosclerotic lesions in ApoE-/- mice after oral administration for 12 weeks. And these effects might mainly attributed to the ability of BSA-SeNPs and CS-SeNPs to inhibit hyperlipidemia by suppressing hepatic cholesterol and fatty acid metabolism, and alleviate oxidative stress by enhancing antioxidant activity. Moreover, the benefits of BSA-SeNPs were dose-dependent and the medium dose of BSA-SeNPs (50 µg Se/kg body weight/day) was optimal. Generally, BSA-SeNPs with mean size 38.5 nm and negative surface charge showed better anti-atherosclerotic effect than CS-SeNPs with mean size 65.8 nm and positive surface charge. These results suggested that SeNPs could significantly alleviate the formation of atherosclerosis in ApoE-/- mice, possibly by inhibiting hyperlipidemia and oxidative stress, exhibiting a potential to serve as an anti-atherosclerotic agent.

BSA/Silver Nanoparticle-Loaded Hydrogel Film for Local Photothermal Treatment of Skin Cancer.

PURPOSE: To develop a hydrogel film containing bovine serum albumin (BSA)-coated silver nanoparticles (BSA/AgNP) and evaluate its applicability for topical photothermal treatment (PTT) of skin cancer. METHODS: BSA/AgNP-loaded hydrogel films were prepared and their swelling, bioadhesive, mechanical, and photothermal properties were characterized in vitro and in vivo. RESULTS: The synthesized BSA/AgNP exhibited a narrow size distribution with good size stability and, notably, possessed great photothermal activity that could stably maintain through repetitive laser irradiation. The BSA/AgNP-loaded hydrogel films showed favorable swelling, bioadhesive, tensile, and photothermal properties. Based on these results, when tested the anti-cancer effects in B16F10 s.c. tumor-bearing mice, the PTT with the topical treatment of BSA/AgNP-loaded hydrogel films could significantly inhibit the tumor growth by a single treatment with no apparent toxicity. CONCLUSIONS: Overall, the results of this study demonstrated that the BSA/AgNP-loaded hydrogel films may serve as an effective but safe topical PTT agent for the treatment of skin cancer.

The effect of four lanthanides onto a rat kidney cell line (NRK-52E) is dependent on the composition of the cell culture medium.

Lanthanide (Ln) exposure poses a serious health risk to animals and humans. In this study, we investigated the effect of 10-9-10-3 M La, Ce, Eu, and Yb exposure onto the viability of rat renal NRK-52E cells in dependence on Ln concentration, exposure time, and composition of the cell culture medium. Especially, the influence of fetal bovine serum (FBS) and citrate onto Ln cytotoxicity, solubility, and speciation was investigated. For this, in vitro cell viability studies using the XTT assay and fluorescence microscopic investigations were combined with solubility and speciation studies using TRLFS and ICP-MS, respectively. The theoretical Ln speciation was predicted using thermodynamic modeling. All Ln exhibit a concentration- and time-dependent effect on NRK-52E cells. FBS is the key parameter influencing both Ln solubility and cytotoxicity. We demonstrate that FBS is able to bind Ln3+ ions, thus, promoting solubility and reducing cytotoxicity after Ln exposure for 24 and 48 h. In contrast, citrate addition to the cell culture medium has no significant effect on Ln solubility and speciation nor cytotoxicity after Ln exposure for 24 and 48 h. However, a striking increase of cell viability is observable after Ln exposure for 8 h. Out of the four Ln elements under investigation, Ce is the most effective. Results from TRLFS and solubility measurements correlate well to those from in vitro cell culture experiments. In contrast, results from thermodynamic modeling do not correlate to TRLFS results, hence, demonstrating that big gaps in the database render this method, currently, inapplicable for the prediction of Ln speciation in cell culture media. Finally, this study demonstrates the importance and the synergistic effects of combining chemical and spectroscopic methods with cell culture techniques and biological methods.

Subcutaneous Delivery of Albumin: Impact of Thermosensitive Hydrogels.

Albumin demonstrates remarkable promises as a versatile carrier for therapeutic and diagnostic agents. However, noninvasive delivery of albumin-based therapeutics has been largely unexplored. In this study, injectable thermosensitive hydrogels were evaluated as sustained delivery systems for Cy5.5-labeled bovine serum albumin (BSA-Cy5.5). These hydrogels were prepared using aqueous solutions of Poloxamer 407 (P407) or poly(lactide-co-glycolide)-block-poly(ethylene glycol)-block-poly(lactide-co-glycolide) (PLGA-PEG-PLGA), which could undergo temperature-triggered phase transition and spontaneously solidify into hydrogels near body temperature, serving as in situ depot for tunable cargo release. In vitro, these hydrogels were found to release BSA-Cy5.5 in a sustained manner with the release half-life of BSA-Cy5.5 from P407 and PLGA-PEG-PLGA hydrogels at 16 h and 105 h, respectively. Without affecting the bioavailability, subcutaneous administration of BSA-Cy5.5-laden P407 hydrogel resulted in delayed BSA-Cy5.5 absorption, which reached the maximum plasma level (Tmax) at 24 h, whereas the Tmax for subcutaneously administered free BSA-Cy5.5 solution was 8 h. Unexpectedly, subcutaneously injected BSA-Cy5.5-laden PLGA-PEG-PLGA hydrogel did not yield sustained BSA-Cy5.5 plasma level, the bioavailability of which was significantly lower than that of P407 hydrogel (p < 0.05). The near-infrared imaging of BSA-Cy5.5-treated mice revealed that a notable portion of BSA-Cy5.5 remained trapped within the subcutaneous tissues after 6 days following the subcutaneous administration of free solution or hydrogels, suggesting the discontinuation of BSA-Cy5.5 absorption irrespective of the formulations. These results suggest the opportunities of developing injectable thermoresponsive hydrogel formulations for subcutaneous delivery of albumin-based therapeutics.

Establishment of an immunological detection method of fleroxacin by fluorescence-linked immunosorbent assay.

The direct and indirect competitive fluorescence-linked immunosorbent assay (FLISA and icFLISA) incorporating quantum dots (QDs) for the detection of fleroxacin (FLE) was established for the first time in this study. The monoclonal antibody specific for FLE was successfully conjugated with QDs after purification by the caprylic acid-ammonium sulphate method. The limits of detection of FLISA and icFLISA were 0.012 ng/mL and 0.006 ng/mL, respectively; IC50 were 0.32 ng/mL and 0.19 ng/mL; and the detection ranges were 0.012-24.490 ng/mL and 0.006-16.210 ng/mL. The recovery was 93.8%-112.4% and the coefficient of variation was below 11.75%. The fabricated FLISA and icFLISA are cost-effective, high sensitive and can be an alternative method in the detection of FLE residues.

Delivery of functional exogenous proteins by plant-derived vesicles to human cells in vitro.

Plant-derived extracellular vesicles (EVs) gain more and more attention as promising carriers of exogenous bioactive molecules to the human cells. Derived from various edible sources, these EVs are remarkably biocompatible, biodegradable and highly abundant from plants. In this work, EVs from grapefruit juice were isolated by differential centrifugation followed by characterization of their size, quantity and morphology by nanoparticle tracking analysis, dynamic light scattering, atomic force microscopy and cryo-electron microscopy (Cryo-EM). In Cryo-EM experiments, we visualized grapefruit EVs with the average size of 41 ± 13 nm, confirmed their round-shaped morphology and estimated the thickness of their lipid bilayer as 5.3 ± 0.8 nm. Further, using cell culture models, we have successfully demonstrated that native grapefruit-derived extracellular vesicles (GF-EVs) are highly efficient carriers for the delivery of the exogenous Alexa Fluor 647 labeled bovine serum albumin (BSA) and heat shock protein 70 (HSP70) into both human peripheral blood mononuclear cells and colon cancer cells. Interestingly, loading to plant EVs significantly ameliorated the uptake of exogenous proteins by human cells compared to the same proteins without EVs. Most importantly, we have confirmed the functional activity of human recombinant HSP70 in the colon cancer cell culture upon delivery by GF-EVs. Analysis of the biodistribution of GF-EVs loaded with 125I-labeled BSA in mice demonstrated a significant uptake of the grapefruit-derived extracellular vesicles by the majority of organs. The results of our study indicate that native plant EVs might be safe and effective carriers of exogenous proteins into human cells.

Development of a novel intraarticular injection of diclofenac for the treatment of arthritis: a preclinical study in the rabbit model.

PURPOSE: To develop a novel intraarticular injection of diclofenac for the treatment of arthritis. METHOD: Diclofenac loaded nanoparticles were prepared by a nanoprecipitation technique using Eudragit L 100 as the polymer and polyvinyl alcohol as the surfactant. The nanoparticles were evaluated for particle size, zeta potential, scanning electron microscopy, drug release, encapsulation efficiency, and loading efficiency studies. The optimized nanoparticulate formulation was developed for intra articular injection. Intraarticulate injection was evaluated for pH, appearance, viscosity, osmolarity and syringability studies. The optimized injection formulation was tested in an arthritic model consisting of 25 rabbits. RESULT: Nanoprecipitation method was found to be suitable for diclofenac nanoparticles. The shape of the prepared nanoparticles was found to be spherical and devoid of any cracks and crevices. The average particle size of a diclofenac nanoparticle was found to range from 87±0.47 to 103±0.26 nm. The zeta potential of the prepared nanoparticles was found to be in the range of 0.598±0.34 to 0.826±0.25 mV. The encapsulation efficiency was found to be between 73.45% to 99.03%, while the drug loading was observed between 10.34 to 35.32%. The percentage drug release at 12 hours was found to range from 73.45% to 99.03%. CONCLUSION: The developed intraarticular injection was found to be within the physically and chemically accepted limits. Animals treated with the intra articular injection of diclofenac showed a significant reduction in swelling as compares to the other groups.

An Albumin-Based Therapeutic Nanosystem for Photosensitizer/Protein Co-Delivery to Realize Synergistic Cancer Therapy.

Oxygen-dependent photodynamic therapy (PDT) is hindered by the limited availability of endogenous oxygen in solid tumors and low tumor accumulation of photosensitizers. Herein, we developed a biocompatible cancer-targeted therapeutic nanosystem based on cRGD conjugated bovine serum albumin (CBSA) co-loaded with a photosensitizer (chlorin e6, Ce6) and a therapeutic protein (cytochrome c, Cytc) for synergistic photodynamic and protein therapy. The nanosystem (Ce6/Cytc@CBSA) can target αVß3 integrin overexpressed cancer cells to improve tumor accumulation due to incorporation of cRGD. In the intracellular environment, Ce6 is released to produce toxic singlet oxygen upon near-infrared irradiation. At the same time, the therapeutic protein, Cytc, can induce programmed cell death by activating the downstream caspase pathway. Most importantly, Cytc with the catalase-like activity accelerates O2 generation by decomposing excess H2O2 in cancer cells, thereby relieving the PDT-induced hypoxia to enhance therapeutic efficacy. Both in vitro and in vivo studies reveal the significantly improved antitumor effects of the combined photodynamic/protein therapy, indicating that Ce6/Cytc@CBSA shows great potential in synergetic cancer treatments.

Entrapment and release kinetics study of dyes from BSA microspheres forming a matrix and a reservoir system.

Two kinds of Bovine Serum Albumin (BSA)-loaded microspheres were prepared in water-organic bilayer systems using ultrasonic irradiation. The first method included an aqueous solution of BSA and water-soluble dye together, mixed with dodecane, that upon sonication formed a matrix system where the dye is concentrated in the protein shell. The other system included an aqueous solution of BSA mixed with octanol-soluble dye that, upon sonication, formed a reservoir system in which the dye filled the inner volume of the microspheres. Each of these microspheres was prepared with two different dyes and their leaching profiles into pure solvents were studied using UV-vis spectrometry. Fast leaching was observed at the beginning for both systems, which levelled-off after a certain time. For the matrix system, an equilibrium state was obtained after 100-200 hours, whereas for the reservoir system, leaching occurred much faster, within 1-3 hours. Such systems can serve as models for drug delivery agents.

Protamine and BSA-dextran complex emulsion improves oral bioavailability and anti-tumor efficacy of paclitaxel.

Food protein and polysaccharide complex emulsions are safe carriers of hydrophobic drugs and nutrients. To improve oral bioavailability and therapeutic/healthy efficacy of hydrophobic drugs and nutrients, herein, protamine (PRO), a cationic cell-penetrating peptide, was introduced into protein and polysaccharide complex emulsion. The electrostatic complex of PRO and BSA-dextran conjugate (BD) produced by Maillard reaction was used as emulsifier to produce oil-in-water emulsion (@BD/PRO). The BSA molecules were crosslinked at the oil-water interface by a heat treatment and the PRO chains were simultaneously anchored in the interface. BD emulsion (@BD) without PRO was produced for comparation. Paclitaxel (PTX), a hydrophobic antineoplastic drug, was encapsulated in the emulsions with 99% loading efficiency and 6.4% loading capacity. The emulsions had long-term stability. The bioavailability and H22 tumor inhibition efficacy of PTX@BD/PRO were 40% and 70% higher than those of PTX@BD, respectively, after oral administration in the mice. More importantly, orally administrated PTX@BD/PRO had the same anti-tumor efficacy as intravenously injected commercial PTX injection. No abnormality was observed in the main organs of the mice after consecutive oral administration of PTX@BD/PRO. This study indicates that @BD/PRO is an excellent carrier of hydrophobic drugs/nutrients and is suitable for long-term oral administration.

Targeted MRI and chemotherapy of ovarian cancer with clinic available nano-drug based nanoprobe.

Cancer is the leading cause of death worldwide, and chemotherapy, as its main treatment, has side effects in clinical application due to lack of targeting selectivity to tumor tissues. Theranostic nanomaterials have shown wonderful functions for the diagnosis and therapy of disease benefitting from the controllability of nanomaterials. However, there is still little available for clinical transformation due to the uncertain biocompatibility. It is urgent to develop nanoprobes possessing bright transformation potentials. This study reports a facile biomineralization route to synthesize the theranostic nanoprobe using the clinic available nano-drug (trademark Abraxane). Further profiting from the binding ability of albumin to metal cations, we successfully prepared biocompatible nanoprobe, BSA-Gd2O3/PTX@Anti-HE4 mAb, for the targeted magnetic resonance imaging and chemotherapy of ovarian carcinoma. The obtained nanoprobe has the advantages of uniform particle size, good dispersibility and favorable stability. In vivo and in vitro experiment results showed that the nanoprobe can realize targeted magnetic resonance imaging and chemotherapy of ovarian carcinoma. Such a novel multifunctional nanoprobe based on clinic nano-drug might be promising for clinic transformation.

Preparation and Evaluation of Cabazitaxel-Loaded Bovine Serum Albumin Nanoparticles for Prostate Cancer.

PURPOSE: Cabazitaxel (CBZ) is a new taxane-based antitumor drug approved by the FDA for the treatment of prostate cancer, especially for patients with advanced prostate cancer for whom docetaxel is ineffective or causes aggravation. However, Tween 80 injection can cause serious allergic reactions, and CBZ itself has strong toxicity, adverse reactions, and poor tumor selectivity, which greatly limits its clinical applications. Therefore, the CBZ-loaded bovine serum albumin nanoparticles (CBZ-BSA-Gd-NPs) were developed to overcome the allergenic response of Tween 80 and realize the integration of diagnosis and treatment. METHODS: CBZ-BSA-Gd-NPs were prepared by the biomineralization method. The characterization, magnetic resonance imaging (MRI), safety, and antitumor activity of the nanoparticles were evaluated in vitro and in vivo. RESULTS: The prepared nanoparticles were uniform in size (166 nm), with good MRI performance and stability over 24 h. Compared with CBZ-Tween 80 injection, CBZ-BSA-Gd-NPs showed much lower hemolysis, similar tumor inhibition, and enhanced cellular uptake in vitro. The pharmacokinetic behavior of CBZ-BSA-Gd-NPs in rats showed that the retention time of the nanoparticles was prolonged, the clearance rate decreased, and the area under the drug-time curve increased. The distribution of CBZ-BSA-Gd-NPs in nude mice was characterized by UPLC-MS/MS and MRI, and the results showed that CBZ-BSA-Gd-NPs could effectively target tumor tissues with reduced distribution in the heart, liver, spleen, lungs, and kidneys compared with CBZ-Tween 80, which indicated that CBZ-BSA-Gd-NPs not only had a passive targeting effect on tumor tissue but also achieved the integration of diagnosis and treatment. In vivo, CBZ-BSA-Gd-NPs showed improved tumor inhibitory effect with a safer profile. CONCLUSION: In summary, CBZ-BSA-Gd-NPs can serve as an effective therapeutic drug carrier to deliver CBZ into prostate cancer, and realize the integration of diagnosis and therapy.

Characteristics, Cryoprotection Evaluation and In Vitro Release of BSA-Loaded Chitosan Nanoparticles.

Chitosan nanoparticles (CS-NPs) are under increasing investigation for the delivery of therapeutic proteins, such as vaccines, interferons, and biologics. A large number of studies have been taken on the characteristics of CS-NPs, and very few of these studies have focused on the microstructure of protein-loaded NPs. In this study, we prepared the CS-NPs by an ionic gelation method, and bovine serum albumin (BSA) was used as a model protein. Dynamic high pressure microfluidization (DHPM) was utilized to post-treat the nanoparticles so as to improve the uniformity, repeatability and controllability. The BSA-loaded NPs were then characterized for particle size, Zeta potential, morphology, encapsulation efficiency (EE), loading capacity (LC), and subsequent release kinetics. To improve the long-term stability of NPs, trehalose, glucose, sucrose, and mannitol were selected respectively to investigate the performance as a cryoprotectant. Furthermore, trehalose was used to obtain re-dispersible lyophilized NPs that can significantly reduce the dosage of cryoprotectants. Multiple spectroscopic techniques were used to characterize BSA-loaded NPs, in order to explain the release process of the NPs in vitro. The experimental results indicated that CS and Tripolyphosphate pentasodium (TPP) spontaneously formed the basic skeleton of the NPs through electrostatic interactions. BSA was incorporated in the basic skeleton, adsorbed on the surface of the NPs (some of which were inlaid on the NPs), without any change in structure and function. The release profiles of the NPs showed high consistency with the multispectral results.