Combination of selol nanocapsules and magnetic hyperthermia hinders breast tumor growth in aged mice after a short-time treatment.

Short time treatment with reduced dosages of selol-loaded PLGA nanocapsules (NcSel) combined with magnetic hyperthermia (MHT) is evaluated in aged Erhlich tumor-bearing mice. Clinical, hematological, biochemical, genotoxic and histopathological parameters are assessed during 7 d treatment with NcSel and MHT, separately or combined. The time evolution of the tumor volume is successfully modeled using the logistic mathematical model. The combined therapy comprising NcSel and MHT is able to hinder primary tumor growth and a case of complete tumor remission is recorded. Moreover, no metastasis was diagnosed and the adverse effects are negligible. NcSel plus MHT may represent an effective and safe alternative to cancer control in aged patients. Future clinical trials are encouraged.

Comparison between direct use and PLGA nanocapsules containing drug of traditional Chinese medicine, Tiaojing Zhixue, in treatment of dysfunctional uterine bleeding.

Dysfunctional uterine bleeding is menstrual bleeding in abnormal volume, duration, or time, and it is a common problem in women. A wide range of drug therapies, with varying efficacy, is available for women with dysfunctional uterine bleeding. The use of herbal and traditional medicine is one of the ways to treat this disease, which has fewer side effects than chemical drugs. On the other hand, these medicines have less effect on treatment than chemical drugs. Therefore, increasing their effectiveness in the treatment of diseases has always been important. For this purpose, in this study, a comparison was done between direct use and PLGA nanocapsules containing Tiaojing Zhixue, in the treatment of dysfunctional uterine bleeding. First, PLGA nanocapsules containing Tiaojing Zhixue were synthesized by the electrospray technique. Then 80 women with dysfunctional uterine bleeding were treated with this medicine. These people were divided into two groups of 40 people. The first group was treated with 20mg of Tiaojing Zhixue and the other group was treated with PLGA nanocapsules containing Tiaojing Zhixue for eight months. The duration and frequency of bleeding from one month before the start of treatment and during the eight months after the start of treatment (second, fourth, and eighth month) were assessed in two groups. The two groups were homogeneous in terms of mean frequency of bleeding and mean duration of bleeding before starting treatment. The positive response in the PLGA nanocapsules treatment group (75%) was higher than the direct use drug treatment group (42.5%) (P < 0.01). The rate of side effects was the same in each group. Due to the effectiveness of PLGA nanocapsules in the treatment of dysfunctional uterine bleeding and the lack of side effects, it can be considered as an alternative medicine for the treatment of this disorder.

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.

Sustained release of epigallocatechin-3-gallate from chitosan-based scaffolds to promote osteogenesis of mesenchymal stem cell.

Epigallocatechin-3-gallate (EGCG) is a kind of flavonoids and has the ability to promote differentiation of mesenchymal stem cells (MSCs) into osteoblasts. However, the EGCG is easily metabolized by cells during cell culture, which reduces its bioavailability. Therefore, in this paper, EGCG-loaded chitosan nanoparticles (ECN) were fabricated and entrapped into chitosan/alginate (CS/Alg) scaffolds to form CS/Alg-ECN scaffolds for improving the bioavailability of EGCG. The human umbilical cord mesenchymal stem cells (HUMSCs) were cultured on CS/Alg-ECN scaffolds to induce osteogenic differentiation. The results indicated that the CS/Alg-ECN scaffolds continuously released EGCG for up to 16 days. Besides, these results suggested that CS/Alg-ECN scaffolds promoted osteoblast differentiation through activating Wnt/ß-catenin signaling pathway. Collectively, this study demonstrated that the entrapment ECN into CS/Alg scaffolds was a promising strategy for promoting osteogenesis of MSCs.

Chitosan based-nanoparticles and nanocapsules: Overview, physicochemical features, applications of a nanofibrous scaffold, and bioprinting.

Recent advancements in the synthesis, properties, and applications of chitosan as the second after cellulose available biopolymer in nature were discussed in this review. A general overview of processing and production procedures from A to Z was highlighted. Chitosan exists in three polymorphic forms which differ in degree of crystallinity (α, ß, and γ). Thus, the degree of deacetylation, crystallinity, surface area, and molecular mass significantly affect most applications. Otherwise, the synthesis of chitosan nanofibers is suffering from many drawbacks that were recently treated by co-electrospun with other polymers such as polyvinyl alcohol (PVA), polyethylene oxide (PEO), and polycaprolactone (PCL). Ultimately, this review focuses on the area of new trend utilization of chitosan nanoparticles as nanospheres and nanocapsules, in cartilage and bone regenerative medicine. Owing to its biocompatibility, bioavailability, biodegradability, and costless synthesis, chitosan is a promising biopolymeric structure for water remediation, drug delivery, antimicrobials, and tissue engineering.

Reprogramming bacterial protein organelles as a nanoreactor for hydrogen production.

Compartmentalization is a ubiquitous building principle in cells, which permits segregation of biological elements and reactions. The carboxysome is a specialized bacterial organelle that encapsulates enzymes into a virus-like protein shell and plays essential roles in photosynthetic carbon fixation. The naturally designed architecture, semi-permeability, and catalytic improvement of carboxysomes have inspired rational design and engineering of new nanomaterials to incorporate desired enzymes into the protein shell for enhanced catalytic performance. Here, we build large, intact carboxysome shells (over 90 nm in diameter) in the industrial microorganism Escherichia coli by expressing a set of carboxysome protein-encoding genes. We develop strategies for enzyme activation, shell self-assembly, and cargo encapsulation to construct a robust nanoreactor that incorporates catalytically active [FeFe]-hydrogenases and functional partners within the empty shell for the production of hydrogen. We show that shell encapsulation and the internal microenvironment of the new catalyst facilitate hydrogen production of the encapsulated oxygen-sensitive hydrogenases. The study provides insights into the assembly and formation of carboxysomes and paves the way for engineering carboxysome shell-based nanoreactors to recruit specific enzymes for diverse catalytic reactions.

A multiple drug loaded, functionalized pH-sensitive nanocarrier as therapeutic and epigenetic modulator for osteosarcoma.

Osteosarcoma is a malignant condition affecting adolescents and children more than adults. Nanobiomedicine has opened up several avenues which have increased therapeutic efficiencies than the conventional treatment for the same. In the current study, a novel organic nanoparticle was devised conjugated with bisphosphonate zoledronic acid which has an affinity for bone tissues. Moreover, the nanoparticle was loaded with multiple anti-cancer drugs like gemcitabine and epirubicin. The nanoparticles were characterized by microscopic analysis, entrapment and loading efficiencies, bone affinity studies, in-vitro release studies, cytotoxicity studies and finally in-vivo tumor regression studies. Bone affinity studies depicted a high affinity of zoledronic acid towards bone powder. The nanoparticle exhibited a nanosize dimension, high entrapment and loading efficiencies with uniform symmetry devoid of agglomeration. The in-vitro release experiments showed a measured release of drugs over a longer time without any hint of burst release. However, the release was comparatively for a longer duration in acidic pH and normal physiological pH which may be excellent for therapeutic efficiency. The cytotoxicity studies revealed enhanced cytotoxic effect for MG-63 cell lines in comparison of free drug or single drug combinations. Nonetheless, they proved to be cytocompatible with primary bone cells. Additionally, cellular uptake of nanoparticle was appreciably improved. Significant tumor (250%) regression was seen upon treatment with multiple drug loaded zoledronic acid conjugated nanoparticle, along with epigenetic changes affecting microRNA expressions. The increased cytotoxicity and increased cellular uptake may be of greater advantage in systemic osteosarcoma therapy. Combining all results, our study demonstrated substantial potential towards management of osteosarcoma.

Antitumoral Drug: Loaded Hybrid Nanocapsules Based on Chitosan with Potential Effects in Breast Cancer Therapy.

Cancer remains one of the world's most devastating diseases and is responsible for more than 20% of all deaths. It is defined as uncontrolled proliferation of cells and spreads rapidly to healthy tissue. Controlled drug delivery systems offers great opportunities for the development of new non-invasive strategies for the treatment of cancers. The main advantage of these systems is their capacity to accumulate in tumors via enhanced permeability and retention effects. In the present study, an innovative hybrid drug delivery system based on nanocapsules obtained from the interfacial condensation between chitosan and poly(N-vinyl pyrrolidone-alt-itaconic anhydride) and containing both magnetic nanoparticles and an antitumoral drug was developed in order to improve the efficiency of the antitumoral treatment. Using dynamic light scattering, it was observed that the mean diameter of these hybrid nanocapsules was in the range of 43 to 142 nm. SEM confirmed their nanometric size and their well-defined spherical shape. These nanocapsules allowed the encapsulation of an increased amount of 5-fluorouracil and provided controlled drug release. In vitro studies have revealed that these drug-loaded hybrid nanocapsules were able to induce a cytostatic effect on breast carcinoma MCF-7 cell lines (Human Caucasian breast adenocarcinoma - HTB-22) comparable to that of the free drug.

Encapsulation for Cancer Therapy.

The current rapid advancement of numerous nanotechnology tools is being employed in treatment of many terminal diseases such as cancer. Nanocapsules (NCs) containing an anti-cancer drug offer a very promising alternative to conventional treatments, mostly due to their targeted delivery and precise action, and thereby they can be used in distinct applications: as biosensors or in medical imaging, allowing for cancer detection as well as agents/carriers in targeted drug delivery. The possibility of using different systems-inorganic nanoparticles, dendrimers, proteins, polymeric micelles, liposomes, carbon nanotubes (CNTs), quantum dots (QDs), biopolymeric nanoparticles and their combinations-offers multiple benefits to early cancer detection as well as controlled drug delivery to specific locations. This review focused on the key and recent progress in the encapsulation of anticancer drugs that include methods of preparation, drug loading and drug release mechanism on the presented nanosystems. Furthermore, the future directions in applications of various nanoparticles are highlighted.

Morphological Transformation between Orthogonal Dynamic Covalent Self-Assembly of Imine-Boroxine Hybrid Polymer Nanocapsules and Thin Films via Linker Exchange.

Orthogonal dynamic covalent self-assembly is used as a facile method for constructing polymer hollow nanocapsules (NCs) and thin films. The bifunctional precursor 4-formylphenylboronic acid is symmetrically installed with a boronic acid group for the boroxine linkage, and an aldehyde group for the Schiff base reaction which can react with twofold symmetry linkers ethylenediamine and para phenylenediamine to attain polymer NCs and nanosheets. Owing to the reversibility of the imine linkages, the mutual morphological transformation between polymer NCs and thin films via an amine-imine-exchange strategy is successfully achieved. Multiple reversible covalent bonds allow the control the release of the load in polymer NCs using different techniques. This may be useful for designing stimulus-responsive smart materials.

Dutasteride nanocapsules for hair follicle targeting: Effect of chitosan-coating and physical stimulus.

In general, nanometer-sized drug delivery systems have a natural tendency for accommodation in the follicular cavities, which makes them advantageous in the treatment of conditions affecting these structures. Still, follicular targeting enhancement can improve therapy outcomes. Here, we compare two strategies to further promote dutasteride follicular-targeted delivery: the chemical modulation of nanosystem surface properties by coating with the natural polymer chitosan, and the application of a massage. For this, poly-(ɛ-caprolactone)-lipid-core nanocapsules (NC) containing dutasteride were developed and had their permeation profile compared to chitosan-coated nanocapsules (NC-CS). Nanocapsules showed high drug encapsulation efficiency (>94%), and stability for up to 90 days of storage. As expected, chitosan coating increased the size and zeta potential, from 199.0 ± 0.5 nm (PdI of 0.12) and - 13.6 ± 0.6 mV to 224.9 ± 3.4 nm (PdI 0.23) and + 40.2 ± 0.8 mV, respectively. Both coated and non-coated nanoparticles targeted the hair follicles compared to a drug solution. Enhanced hair follicles targeting was observed after the massage procedure, with 5 and 2-fold increases relative to NC and NC-CS, respectively. In conclusion, this work demonstrates dutasteride nanocapsules can target the follicular casts, and a simple physical stimulation can enhance 5-times the drug amount accumulated.

Electrosprayed whey protein-based nanocapsules for ß-carotene encapsulation.

In this work an electrohydrodynamic process (electrospray) was used to produce ß-carotene loaded nanocapsules based on whey protein isolate (WPI). WPI solutions were prepared in aqueous solutions with different concentrations of ethanol (5, 10 and 15%) which were used for ß-carotene solubilization. Different electrospray conditions were tested and the morphology and molecular organization of the nanocapsules were studied on dried and hydrated state. The size of the dried nanocapsules ranged between 227 and 283 nm. After hydration, there was a significant increase in the mean size of the nanocapsules, being the sizes higher for nanocapsules produced with increasing concentrations of ethanol. Results, obtained from the reactivity of free sulfhydryl groups and fluorescence analysis, showed that the increase of ethanol concentration had a destabilizing effect on the protein unfolding. Electrosprayed WPI-based nanocapsules can be used for the encapsulation of ß-carotene answering the industrial demand for novel encapsulation technologies to protect sensitive bioactive compounds.

Biological response and cytotoxicity induced by lipid nanocapsules.

BACKGROUND: Lipid nanocapsules (LNCs) are promising vehicles for drug delivery. However, since not much was known about cellular toxicity of these nanoparticles in themselves, we have here investigated the mechanisms involved in LNC-induced intoxication of the three breast cancer cell lines MCF-7, MDA-MD-231 and MDA-MB-468. The LNCs used were made of Labrafac™ Lipophile WL1349, Lipoid® S75 and Solutol® HS15. RESULTS: High resolution SIM microscopy showed that the DiD-labeled LNCs ended up in lysosomes close to the membrane. Empty LNCs, i.e. without encapsulated drug, induced not only increased lysosomal pH, but also acidification of the cytosol and a rapid inhibition of protein synthesis. The cytotoxicity of the LNCs were measured for up to 72 h of incubation using the MTT assay and ATP measurements in all three cell lines, and revealed that MDA-MB-468 was the most sensitive cell line and MCF-7 the least sensitive cell line to these LNCs. The LNCs induced generation of reactive free oxygen species and lipid peroxidation. Experiments with knock-down of kinases in the near-haploid cell line HAP1 indicated that the kinase HRI is essential for the observed phosphorylation of eIF2α. Nrf2 and ATF4 seem to play a protective role against the LNCs in MDA-MB-231 cells, as knock-down of these factors sensitizes the cells to the LNCs. This is in contrast to MCF-7 cells where the knock-down of these factors had a minor effect on the toxicity of the LNCs. Inhibitors of ferroptosis provided a large protection against LNC toxicity in MDA-MB-231 cells, but not in MCF-7 cells. CONCLUSIONS: High doses of LNCs showed a different degree of toxicity on the three cell lines studied, i.e. MCF-7, MDA-MD-231 and MDA-MB-468 and affected signaling factors and the cell fate differently in these cell lines.

Preparation and Characterization of Simvastatin Nanocapsules: Encapsulation of Hydrophobic Drugs in Calcium Alginate.

During past few years, development of methods for physical encapsulation of drugs in biocompatible materials in mild conditions for poorly water-soluble hydrophobic drugs which are sensitive to hydrolytic conditions is of high interest in biomedical and pharmaceutical industries. The encapsulation can improve the drug solubility while decreases its side effects besides controlling its pharmacokinetic profile which results in the overall improvement of the therapeutic efficacy. In the current paper, we provide a detailed protocol for encapsulation of poorly water-soluble hydrophobic drugs which is a development of the previously developed protocol of nanocapsule formation by complex formation on the interface of emulsion droplets. The newly developed protocol is based on nanocapsule formation by complex formation on the interface of emulsion droplets except using no organic solvent for potential targeted drug delivery to glioblastoma cells. Simvastatin as a model of hydrophobic drugs of high hydrolytic sensitivity was encapsulated in calcium alginate hydrogel as a biocompatible matrix using the developed protocol. Simvastatin belongs to a group of mevalonate cascade inhibitors (statins) which have recently been considered as a possible new approach in cancer treatment especially glioblastoma. As a cholesterol biosynthesis inhibitor, it is very important to deliver statins only to target cells and not intact cells using targeted drug delivery strategies to avoid dysregulation of cholesterol biosynthesis in normal tissue. To prepare the statin drug nanocarrier's, the drug was first dissolved in polysorbate 20 nonionic surfactant solution, and then peptide modified calcium alginate was deposited on the micelles interface at neutral pH and 30 °C. The prepared nanocapsules were spherical in shape and very small in size (i.e., 17 ± 5 nm). The drug content of the nanocapsules was 117.3 mg g-1 and the drug loading efficiency for a 5-mg initial amount of the drug was 23.5% ± 3.1%.

Construction of a Macrophage-Targeting Bio-nanocapsule-Based Nanocarrier.

The construction protocol of bio-nanocapsule (BNC)-based nanocarriers, named GL-BNC and GL-virosome, for targeted drug delivery to macrophages is described here. First, genes encoding the Streptococcus sp. protein G-derived C2 domain (binds to IgG Fc) and Finegoldia magna protein L-derived B1 domain (binds to Igκ light chain) are prepared by PCR amplification. Subsequently, the genes encoding hepatic cell-specific binding domain of hepatitis B virus envelope L protein are replaced by these PCR products. The expression plasmid for this fused gene (encoding GL-fused L protein) can be used to transform Saccharomyces cerevisiae AH22R- cells. To obtain GL-BNC, the transformed yeast cells are disrupted with glass beads, treated with heat, and then subjected to IgG affinity column chromatography followed by size exclusion column chromatography. In addition, GL-BNCs can be fused with liposomes to form GL-virosome. The targeted delivery of GL-BNC and GL-virosome to macrophages can be confirmed by in vitro phagocytosis assays using the murine macrophage cell line RAW264.7.

Fast Biofilm Penetration and Anti-PAO1 Activity of Nebulized Azithromycin in Nanoarchaeosomes.

Azithromycin (AZ) is a broad-spectrum antibiotic with anti-inflammatory and antiquorum sensing activity against biofilm forming bacteria such as Pseudomonas aeruginosa. AZ administered by oral or parenteral routes, however, neither efficiently accesses nor remains in therapeutic doses inside pulmonary biofilm depths. Instead, inhaled nanocarriers loaded with AZ may revert the problem of low accessibility and permanence of AZ into biofilms, enhancing its antimicrobial activity. The first inhalable nanovesicle formulation of AZ, nanoarchaeosome-AZ (nanoARC-AZ), is here presented. NanoARC prepared with total polar archaeolipids (TPAs), rich in 2,3-di-O-phytanyl-sn-glycero-1-phospho-(3'-sn-glycerol-1'-methylphosphate) (PGP-Me) from Halorubrum tebenquichense archaebacteria, consisted of ∼180 nm-diameter nanovesicles, loaded with 0.28 w/w AZ/TPA. NanoARC-AZ displayed lower minimal inhibitory concentration and minimal bactericidal concentration, higher preformed biofilm disruptive, and anti-PAO1 activity in biofilms than AZ. NanoARC penetrated and disrupted the structure of the PAO1 biofilm within only 1 h. Two milliliters of 15 µg/mL AZ nanoARC-AZ nebulized for 5 min rendered AZ doses compatible with in vitro antibacterial activity. The strong association between AZ and the nanoARC bilayer, combined with electrostatic attraction and trapping into perpendicular methyl groups of archaeolipids, as determined by Laurdan fluorescence anisotropy, generalized polarization, and small-angle X-ray scattering, was critical to stabilize during storage and endure shear forces of nebulization. NanoARC-AZ was noncytotoxic on A549 cells and human THP-1-derived macrophages, deserving further preclinical exploration as enhancers of AZ anti-PAO1 activity.

Design of polymeric nanocapsules to improve their lympho-targeting capacity.

Aim: To design lympho-targeted nanocarriers with the capacity to enhance the activity of associated drugs/antigens whose target is within the lymphatic system. Materials & methods: Inulin (INU)-based nanocapsules (NCs), negatively charged and positively charged chitosan NCs were prepared by the solvent displacement techniques. The NCs were produced in two sizes: small (70 nm) and medium (170-250 nm). Results:In vitro results indicated that small NCs interacted more efficiently with dendritic cells than the larger ones. The study of the NCs biodistribution in mice, using 3D reconstruction of the popliteal lymph node, showed that small INU NCs have the greatest access and uniform accumulation in different subsets of resident immune cells. Conclusion: Small and negatively charged INU NCs have a potential as lympho-targeted antigen/drug nanocarriers.

Fabricating ß-cyclodextrin based pH-responsive nanotheranostics as a programmable polymeric nanocapsule for simultaneous diagnosis and therapy.

BACKGROUND: Fabrication of a smart drug delivery system that could dramatically increase the efficiency of chemotherapeutic drugs and reduce the side effects is still a challenge for pharmaceutical researchers. By the emergence of nanotechnology, a huge window was opened towards this goal, and a wide type of nanocarriers were introduced for delivering the chemotherapeutic to the cancer cells, among them are cyclodextrins with the ability to host different types of hydrophobic bioactive molecules through inclusion complexation process. AIM: The aim of this study is to design and fabricate a pH-responsive theranostic nanocapsule based on cyclodextrin supramolecular nano-structure. MATERIALS AND METHODS: This nanostructure contains iron oxide nanoparticles in the core surrounded with three polymeric layers including polymeric ß-cyclodextrin, polyacrylic acid conjugated to sulfadiazine, and polyethylenimine functionalized with ß-cyclodextrin. Sulfadiazine is a pH-responsive hydrophobic component capable of making inclusion complex with ß-cyclodextrin available in the first and third layers. Doxorubicin, as an anti-cancer drug model, was chosen and the drug loading and release pattern were determined at normal and acidic pH. Moreover, the biocompatibility of the nanocapsule (with/without drug component) was examined using different techniques such as MTT assay, complement activation, coagulation assay, and hemolysis. RESULTS: The results revealed the successful preparation of a spherical nanocapsule with mean size 43±1.5 nm and negatively charge of -43 mV that show 160% loading efficacy. Moreover, the nanocapsule has an on/off switching release pattern in response to pH that leads to drug released in low acidic pH. The results of the biocompatibility tests indicated that this nano drug delivery system had no effect on blood and immune components while it could affect cancer cells even at very low concentrations (0.3 µg mL-1). CONCLUSION: The obtained results suggest that this is a "switchable" theranostic nanocapsule with potential application as an ideal delivery system for simultaneous cancer diagnosis and therapy.

Cold-Responsive Nanocapsules Enable the Sole-Cryoprotectant-Trehalose Cryopreservation of ß Cell-Laden Hydrogels for Diabetes Treatment.

Islet transplantation has been one promising strategy in diabetes treatment, which can maintain patient's insulin level long-term and avoid periodical insulin injections. However, donor shortage and temporal mismatch between donors and recipients has limited its widespread use. Therefore, searching for islet substitutes and developing efficient cryopreservation technology (providing potential islet bank for transplantation on demand) is in great need. Herein, a novel cryopreservation method is developed for islet ß cells by combining microfluidic encapsulation and cold-responsive nanocapsules (CR-NCs). The cryopreserved cell-laden hydrogels (calcium alginate hydrogel, CAH) can be transplanted for diabetes treatment. During the freezing process, trehalose is released inside ß cells through the CR-NCs and serves as the sole cryoprotectant (CPA). Additionally, CAH helps cells to survive the freeze-thaw process and provide cells with a natural immune barrier in vivo. Different from traditional cryopreservation methods, this method combining the CR-NCs and hydrogel encapsulation replaces the toxic CPAs with natural trehalose. Great preservation results are obtained and transplantation experiments of diabetic rats further prove the excellent glucose regulation ability of such ß cell-laden hydrogels post cryopreservation. This novel cryopreservation method helps to establish a reliable and ready-to-use bank of biological samples for transplantation therapy and other biomedical applications.

Preparation and Characterization of Nanoliposomes for the Entrapment of Bioactive Hydrophilic Globular Proteins.

Liposome nanocapsules have been applied for many purposes in the pharmaceutical, cosmetic, and food industries. Attributes of liposomes include their biocompatibility, biodegradability, non-immunogenicity, non-toxicity, and ability to entrap both hydrophilic and hydrophobic compounds. The classical hydration of thin lipid films in an organic solvent is applied herein as a technique to encapsulate tarin, a plant lectin, in nanoliposomes. Nanoliposome size, stability, entrapment efficiency, and morphological characterization are described in detail. The nanoliposomes are prepared using 1,2-dioleoyl-sn-glycerol-3-phosphoethanolamine (DOPE), 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino(polyethylene glycol)-2000] (ammonium salt; DSPE-MPEG 2000), and cholesterylhemisuccinate (CHEMS) as the main constituents. Lipids are first dissolved in chloroform to obtain a thin lipid film that is subsequently rehydrated in ammonium sulfate solution containing the protein to be entrapped and incubated overnight. Then, sonication and extrusion techniques are applied to generate nanosized unilamellar vesicles. The size and polydispersity index of the nanovesicles are determined by dynamic light scattering, while nanovesicle morphology is assessed by scanning electron microscopy. Entrapment efficiency is determined by the ratio of the amount of unencapsulated protein to original amount of initially loaded protein. Homogeneous liposomes are obtained with an average size of 155 nm and polydispersity index value of 0.168. A high entrapment efficiency of 83% is achieved.