Construction of a highly efficient adsorbent for one-step purification of recombinant proteins: Functionalized cellulose-based monolith fabricated via phase separation method.

Currently, purification step in the recombinant protein manufacture is still a great challenge and its cost far outweighs those of the upstream process. In this study, a functionalized cellulose-based monolith was constructed as an efficient affinity adsorbent for one-step purification of recombinant proteins. Firstly, the fundamental cellulose monolith (CE monolith) was fabricated based on thermally induced phase separation, followed by being modified with nitrilotriacetic acid anhydride through esterification to give NCE monolith. After chelating with Ni2+, the affinity adsorbent NCE-Ni2+ monolith was obtained, which was demonstrated to possess a hierarchically porous morphology with a relatively high surface area, porosity and compressive strength. The adsorption behavior of NCE-Ni2+ monolith towards ß2-microglobulin with 6 N-terminus His-tag (His-ß2M) was evaluated through batch and fixed-bed column experiments. The results revealed that NCE-Ni2+ monolith exhibited a relatively fast His-ß2M adsorption rate with a maximum adsorption capacity of 329.2 mg/g. The fixed-bed column adsorption implied that NCE-Ni2+ monolith showed high efficiency for His-ß2M adsorption. Finally, NCE-Ni2+ monolith was demonstrated to have an excellent His-ß2M purification ability from E. coli lysate with exceptional reusability. Therefore, the resultant NCE-Ni2+ monolith had large potential to be used as an efficient adsorbent for recombinant protein purification in practical applications.

Tumor Microenvironment-Responsive Magnetic Nanofluid for Enhanced Tumor MRI and Tumor multi-treatments.

We prepared a tumor microenvironment-responsive magnetic nanofluid (MNF) for improving tumor targeting, imaging and treatment simultaneously. For this purpose, we synthesized sulfonamide-based amphiphilic copolymers with a suitable pKa at 7.0; then, we utilized them to prepare the tumor microenvironment-responsive MNF by self-assembly of the sulfonamide-based amphiphilic copolymers and hydrophobic monodispersed Fe3O4 nanoparticles at approximately 8 nm. After a series of characterizations, the MNF showed excellent application potential due to the fact of its high stability under physiological conditions and its hypersensitivity toward tumor stroma by forming aggregations within neutral or weak acidic environments. Due to the fact of its tumor microenvironment-responsiveness, the MNF showed great potential for accumulation in tumors, which could enhance MNF-mediated magnetic resonance imaging (MRI), magnetic hyperthermia (MH) and Fenton reaction (FR) in tumor. Moreover, in vitro cell experiment did not only show high biocompatibility of tumor microenvironment-responsive MNF in physiological environment, but also exhibit high efficacy on inhibiting cell proliferation by MH-dependent chemodynamic therapy (CDT), because CDT was triggered and promoted efficiently by MH with increasing strength of alternating magnetic field. Although the current research is limited to in vitro study, these positive results still suggest the great potential of the MNF on effective targeting, diagnosis, and therapy of tumor.

Enhanced tumor penetration for efficient chemotherapy by a magnetothermally sensitive micelle combined with magnetic targeting and magnetic hyperthermia.

The high accumulation and poor penetration of nanocarriers in tumor is a contradiction of nanomedicine, which reduces the efficacy of chemotherapy. Due to the positive effect of hyperthermia on in vivo drug diffusion, we designed a magnetothermally sensitive micelle (MTM) by integrating magnetic targeting (MT), magnetic hyperthermia (MH), and magnetothermally responsive drug release to facilitate simultaneous drug accumulation and penetration in tumor. Accordingly, we synthesized a cyanine7-modified thermosensitive polymer with phase transition at 42.3°C, and utilized it to prepare drug-loaded MTMs by encapsulating superparamagnetic MnFe2O4 nanoparticles and doxorubicin (DOX). The obtained DOX-MTM had not only high contents of DOX (9.1%) and MnFe2O4 (38.7%), but also some advantages such as superparamagnetism, high saturation magnetization, excellent magnetocaloric effect, and magnetothermal-dependent drug release. Therefore, DOX-MTM improved in vitro DOX cytotoxicity by enhancing DOX endocytosis under the assistance of MH. Furthermore, MT and MH enhanced in vivo DOX-MTM accumulation and DOX penetration in tumor, respectively, substantially inhibiting tumor growth (84%) with excellent biosafety. These results indicate the development of an optimized drug delivery system with MH and MH-dependent drug release, introducing a feasible strategy to enhance the application of nanomedicines in tumor chemotherapy.

Dual-modified albumin-polymer nanocomplexes with enhanced in vivo stability for hepatocellular carcinoma therapy.

Etoposide (ETO) is a semi-synthetic derivative of podophyllotoxin with a definite antitumour effect, but its use is hampered by poor solubility and numerous side-effects. In this work, we developed a hyaluronic acid and ethylenediamine dual-modified albumin-polymer nanocomplex for tumour targeted delivery of ETO. The ETO loaded dual-modified albumin-polymer nanocomplexes (E-HEAP NCs) was composed of a hyaluronic acid decorated cationic albumin shell and a stable poly (butyl cyanoacrylate) core. E-HEAP NCs exhibited a high encapsulation efficiency, great stability in vivo. Furthermore, blank HEAP NCs carrier showed excellent biocompatibility in vitro cell cytotoxicity assay. While, E-HEAP NCs represented superior inhibitory effect on HepG2 cells than free ETO. Additionally, E-HEAP NCs exhibited an excellent tumour-targeting effect, due to the enhanced targeting efficacy of hyaluronic acid and albumin-mediated transcytosis. Moreover, E-HEAP NCs displayed an enhanced antitumour effect and extended the survival period in tumour bearing mice. In summary, the developed novel protein-polymer nanocomplex can potentially serve as a drug delivery system for improved cancer therapy.

Development, Optimization, and Evaluation In Vitro/In Vivo of Oral Liquid System for Synchronized Sustained Release of Levodopa/Benserazide.

To enhance efficiency, convenience, and safety of Parkinson's disease (PD) treatment for geriatric patients, an advanced suspension of Levodopa/Benserazide hydrochloride (LD/BH) has been prepared by cation-exchange resin and used to synchronize sustained release of LD and BH by optimizing coating parameters and prescription. For the purpose, LD and BH were immobilized on the surface of cation-exchange resin, respectively. Based on HPLC results, the cation-exchange resin showed high loading capacity. The studies on drug loading mechanism indicated that both drugs were immobilized by electrostatic interaction rather than physical adsorption. After PEG modification, pretreated drug-resin complexes were coated by emulsion-solvent evaporation method. In order to control drug release in a sustained manner, coating parameters of drug-resin microcapsules were optimized respectively by single-factor analysis. Further, coating prescription of the microcapsules was optimized to synchronize sustained release of LD and BH in vitro by orthogonal design. Utilizing optimal LD-resin microcapsules and BH-resin microcapsules, LD/BH suspension, containing both of them, was prepared by an optimal formulation and characterized by accelerated test and pharmacokinetic study in vivo. The accelerated test confirmed high stability of LD/BH suspension. According to pharmacokinetic results in vivo, in contrast with LD/BH commercial tablets, LD/BH suspensions did not only synchronize sustained release of both drugs but also show good bioequivalence. As LD/BH sustained release suspension can synchronize sustained release of multiple active ingredients by oral administration, the suspension presents promising oral dosage forms for geriatric patients with PD. An advanced Levodopa/Benserazide hydrochloride (LD/BH) suspension, prepared by cation-exchange resin and optimized microencapsulation, synchronizes sustained releases of LD and BH in vivo to benefit Parkinson's disease treatment for geriatric patients.

Ratiometric co-encapsulation and co-delivery of doxorubicin and paclitaxel by tumor-targeted lipodisks for combination therapy of breast cancer.

Combination therapy is a promising treatment for certain advanced drug-resistant cancers. Although effective inhibition of various tumor cells was reported in vitro, combination treatment requires improvement in vivo due to uncontrolled ratiometric delivery. In this study, a tumor-targeting lipodisk nanoparticle formulation was developed for ratiometric loading and the transportation of two hydrophobic model drugs, doxorubicin (DOX) and paclitaxel (PTX), in one single platform. Furthermore, a slightly acidic pH-sensitive peptide (SAPSP) incorporated into lipodisks effectively enhanced the tumor-targeting and cell internalization. The obtained co-loaded lipodisks were approximately 30 nm with a pH-sensitive property. The ratiometric co-delivery of two drugs via lipodisks was confirmed in both the drug-resistant MCF-7/ADR cell line and its parental MCF-7 cell line in vitro, as well as in a tumor-bearing mouse model in vivo compared with a cocktail solution of free drugs. Co-loaded lipodisks exerted improved cytotoxicity to tumor cells in culture, particularly to drug-resistant tumor cells at synergistic drug ratios. In an in vivo xenograft mouse model, the anti-tumor ability of co-loaded lipodisks was evidenced by the remarkable inhibitory effect on tumor growth of either MCF-7 or MCF-7/ADR tumors, which may be attributed to the increased and ratiometric accumulation of both drugs in the tumor tissues. Therefore, tumor-specific lipodisks were crucial for the combination treatment of DOX and PTX to completely exert a synergistic anti-cancer effect. It is concluded that for co-loaded lipodisks, cytotoxicity data in vitro could be used to predict their inhibitory activity in vivo, potentially enhancing the clinical outcome of synergistic therapy.

Tumor-specific delivery of doxorubicin through conjugation of pH-responsive peptide for overcoming drug resistance in cancer.

The major obstacles opposed to doxorubicin (Dox) based chemotherapy are the induction of drug resistance, together with non-specific toxicities for healthy cells. In this study, we prepared a peptide-Dox conjugate aimed at offering Dox molecules a tumor-specific functionality and improving the therapeutic effects of Dox against resistant tumor cells. A slightly acidic pH-sensitive peptide (SAPSP) with high selectivity for cancer cells was attached to Dox to obtain SAPSP-Dox prodrug. The structures and properties of this prodrug were characterized, confirming several merits, including desirable pH-sensitive property, good serum stability and favorable release behavior. Cellular uptake studies demonstrated that SAPSP-Dox was preferably accumulated in cancer cells (Dox-sensitive MCF-7 and Dox-resistant MCF-7/ADR), followed by displaying 26-fold less toxic toward noncancerous MCF-10A cells than free Dox do. The conjugated peptides enabled Dox to escape the efflux effect of P-glycoprotein mediated pump via endocytotic pathway, giving rise to remarkable cytotoxicity and apoptotic effect on MCF-7/ADR cells. Moreover, the superior inhibition efficacy of SAPSP-Dox in vivo was more evident in the both drug-sensitive and drug-resistant xenograft tumor animal models, which enabled Dox to primarily accumulated in tumor. The conjugates also demonstrated a longer half-life in plasma and a lower side effect, for example, reduced cardiac toxicity. Evidence of this study suggests that SAPSP-Dox has the potential to be a potent prodrug for treating drug resistant cancers.

A hierarchically porous cellulose monolith: A template-free fabricated, morphology-tunable, and easily functionalizable platform.

Recently, monoliths with continuous porous structure have received much attention for high-performance separation/adsorption matrix in biomedical and environmental fields. This study proposes a novel route to prepare cellulose monoliths with hierarchically porous structure by selecting cellulose acetate (CA) as the starting material. Thermally induced phase separation of CA solution using a mixed solvent affords a CA monolith, which is converted into the cellulose monolith by alkaline hydrolysis. Scanning electron microscopy images of the CA and cellulose monoliths reveal a continuous macropore with rough surface, and nitrogen adsorption/desorption analysis indicates the formation of a mesoporous structure. The macroporous structure could be controlled by changing the fabrication parameters. A series of reactive groups are introduced by chemical modifications on the surface of the cellulose monolith. The facile and diverse modifiability combined with its hydrophilic property make the hierarchically porous cellulose monolith a potential platform for use in separation, purification and bio-related applications.

Targeted Biomimetic Nanoparticles for Synergistic Combination Chemotherapy of Paclitaxel and Doxorubicin.

Codelivery of multiple chemotherapeutics has become a versatile strategy in recent cancer treatment, but the antagonistic behavior of combined drugs limited their application. We developed a recombinant high-density lipoprotein (rHDL) nanoparticle for the precise coencapsulation and codelivery of two established drugs and hypothesized that they could act synergistically to improve anticancer efficacy. The coloaded rHDL was formulated by passively incorporating hydrophobic paclitaxel (PTX), and subsequently remotely loading hydrophilic doxorubicin (Dox) into the same nanoparticles. The resultant rHDL system restored targeted delivery function toward cancer cells via scavenger receptor class B (SR-BI), as confirmed by in vitro confocal imaging and flow cytometry. These coloaded rHDL nanoparticles were remarkably effective in increasing the ratiometric accumulation of drugs in cancer cells and enhancing antitumor response at synergistic drug ratios. In particular, they exhibited more efficacious anticancer effects in an in vitro cytotoxicity evaluation and in a xenograft tumor model of hepatoma compared with free drug cocktail solutions. These results confirm that the coloaded rHDL nanoparticles are promising candidates for the synergistic delivery of drugs with diverse physicochemical properties in cancer treatment integrating efficiency and safety considerations.

Data in support of preparation and functionalization of a clickable polycarbonate monolith.

This data article provides supplementary figures to the research article entitled, "Phase separation approach to a reactive polycarbonate monolith for "click" modifications" (Xin et al., Polymer, 2015, doi:10.1016/j.polymer.2015.04.008). Here, the nitrogen adsorption/desorption isotherms of the prepared porous polycarbonate monolith are shown to classify its inner structure and calculate the specific surface area. The monoliths were modified by using the thiol-ene click chemistry and the olefin metathesis, which was examined by contact angle measurements, FT-IR, solid state 13C NMR spectroscopy as well as thermogravimetric analysis.

Facile fabrication of mesoporous poly(ethylene-co-vinyl alcohol)/chitosan blend monoliths.

Poly(ethylene-co-vinyl alcohol) (EVOH)/chitosan blend monoliths were fabricated by thermally-induced phase separation method. Chitosan was successfully incorporated into the polymeric monolith by selecting EVOH as the main component of the monolith. SEM images exhibit that the chitosan was located on the inner surface of the monolith. Fourier-transform infrared analysis and elemental analysis indicate the successful blend of EVOH and chitosan. BET results show that the blend monoliths had high specific surface area and uniform mesopore structure. Good adsorption ability toward various heavy metal ions was found in the blend monoliths due to the large chelation capacity of chitosan. The blend monoliths have potential application for waste water purification or bio-related applications.