Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Biocompatibility and Stability of Polysaccharide Polyelectrolyte Complexes Aimed at Respiratory Delivery.

ABSTRACT: Chitosan (CS) and chondroitin sulfate (CHS) are natural polymers with demonstrated applicability in drug delivery, while nanoparticles are one of the most explored carriers for transmucosal delivery of biopharmaceuticals. In this work we have prepared CS/CHS nanoparticles and associated for the first time the therapeutic protein insulin. Fluorescein isothiocyanate bovine serum albumin (FITC-BSA) was also used to enable comparison of behaviors regarding differences in molecular weight (5.7 kDa versus 67 kDa). Nanoparticles of approximately 200 nm and positive zeta potential around +20 mV were obtained. These parameters remained stable for up to 1 month at 4 °C. Proteins were associated with efficiencies of more than 50%. The release of FITC-BSA in PBS pH 7.4 was more sustained (50% in 24 h) than that of insulin (85% in 24 h). The biocompatibility of nanoparticles was tested in Calu-3 and A549 cells by means of three different assays. The metabolic assay MTT, the determination of lactate dehydrogenase release, and the quantification of the inflammatory response generated by cell exposure to nanoparticles have indicated an absence of overt toxicity. Overall, the results suggest good indications on the application of CS/CHS nanoparticles in respiratory transmucosal protein delivery, but the set of assays should be widened to clarify obtained results.

SUBMITTER: Rodrigues S

PROVIDER: S-EPMC5512620 | biostudies-other | 2015 Aug

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Similar Datasets

Preferential cellular uptake of amphiphilic macromolecule-lipid complexes with enhanced stability and biocompatibility.

Project description:Amphiphilic macromolecules (AM) were electrostatically complexed with a 1:1 ratio of 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) and 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) to form AM-lipid complexes with drug delivery applications. The complexes exist as AM-coated liposomes and their drug delivery properties can be tuned by altering the AM-lipid weight ratio. The complexation and tuning are achieved in a simple, efficient, and scalable manner. The gradual increase in lipid ratios concurrently increased the zeta potential of the complexes, which directly correlates to increased cell uptake of the complexes in vitro with preferential uptake noted in BT-20 carcinoma cells versus normal fibroblasts. Increasing AM content increased complex steric stability in the presence of serum proteins and reduced the inherent cytotoxicity towards fibroblasts in vitro. AM-lipid complexes solubilized paclitaxel and showed drug-mediated, dose-dependent cytotoxicity towards target BT-20 cells in vitro. AM-lipid complexes make good candidates as drug delivery systems due to their tunable zeta potential, steric stability, inherently low cytotoxicity, and ability to load and deliver insoluble chemotherapeutic agents. Significantly, their preferential uptake in a carcinoma cell line over normal cells in vitro demonstrates a unique, passive targeting approach to delivery anti-cancer therapeutics.

| S-EPMC3564574 | biostudies-literature

Patterned Microstructure Fabrication: Polyelectrolyte Complexes vs Polyelectrolyte Multilayers.

Project description:Polyelectrolyte complexes (PEC) are formed by mixing the solutions of oppositely charged polyelectrolytes, which were hitherto deemed "impossible" to process, since they are infusible and brittle when dry. Here, we describe the process of fabricating free-standing micro-patterned PEC films containing array of hollow or filled microchambers by one-step casting with small applied pressure and a PDMS mould. These structures are compared with polyelectrolyte multilayers (PEM) thin films having array of hollow microchambers produced from a layer-by-layer self-assembly of the same polyelectrolytes on the same PDMS moulds. PEM microchambers "cap" and "wall" thickness depend on the number of PEM bilayers, while the "cap" and "wall" of the PEC microchambers can be tuned by varying the applied pressure and the type of patterned mould. The proposed PEC production process omits layering approaches currently employed for PEMs, reducing the production time from ~2 days down to 2 hours. The error-free structured PEC area was found to be significantly larger compared to the currently-employed microcontact printing for PEMs. The sensitivity of PEC chambers towards aqueous environments was found to be higher compared to those composed of PEM.

| S-EPMC5103270 | biostudies-literature

Stability enhanced polyelectrolyte-coated gold nanorod-photosensitizer complexes for high/low power density photodynamic therapy.

Project description:Photodynamic therapy (PDT) is a promising treatment modality for cancer and other malignant diseases, however safety and efficacy improvements are required before it reaches its full potential and wider clinical use. Herein, we investigated a highly efficient and safe photodynamic therapy procedure by developing a high/low power density photodynamic therapy mode (high/low PDT mode) using methoxypoly(ethylene glycol) thiol (mPEG-SH) modified gold nanorod (GNR)-AlPcS4 photosensitizer complexes. mPEG-SH conjugated to the surface of simple polyelectrolyte-coated GNRs was verified using Fourier transform infrared spectroscopy; this improved stability, reduced cytotoxicity, and increased the encapsulation and loading efficiency of the nanoparticle dispersions. The GNR-photosensitizer complexes were exposed to the high/low PDT mode (high light dose = 80 mW/cm(2) for 0.5 min; low light dose = 25 mW/cm(2) for 1.5 min), and a high PDT efficacy leads to approximately 90% tumor cell killing. Due to synergistic plasmonic photothermal properties of the complexes, the high/low PDT mode demonstrated improved efficacy over using single wavelength continuous laser irradiation. Additionally, no significant loss in viability was observed in cells exposed to free AlPcS4 photosensitizer under the same irradiation conditions. Consequently, free AlPcS4 released from GNRs prior to cellular entry did not contribute to cytotoxicity of normal cells or impose limitations on the use of the high power density laser. This high/low PDT mode may effectively lead to a safer and more efficient photodynamic therapy for superficial tumors.

| S-EPMC4577028 | biostudies-literature

PEO-b-PPO star-shaped polymers enhance the structural stability of electrostatically coupled liposome/polyelectrolyte complexes.

Project description:We propose a strategy to counteract the salt-driven disassembly of multiliposomal complexes made by electrostatic co-assembly of anionic small unilamellar liposomes and cationic star-shaped polyelectrolytes (made of quaternized poly(dimethylaminoethyl methacrylate) (qPDMAEMA100)3.1). The combined action of (qPDMAEMA100)3.1 and a nonionic star-shaped polymer (PEO12-b-PPO45)4, which comprises diblock copolymer arms uniting a poly(ethylene oxide) PEO inner block and a poly(propylene oxide) PPO terminal block, leads to a stabilization of these complexes against disintegration in saline solutions. Hereby, the anchoring of the PPO terminal blocks to the lipid bilayer and the bridging between several liposomes are at the origin of the promoted structural stability. Two-focus fluorescence correlation spectroscopy verifies the formation of multiliposomal complexes with (PEO12-b-PPO45)4. The polyelectrolyte and the amphiphilic polymer work synergistically, as the joint action still assures some membrane integrity, which is not seen for the mere (PEO12-b-PPO45)4-liposome interaction alone.

| S-EPMC6336312 | biostudies-literature

Development of Polyelectrolyte Complexes for the Delivery of Peptide-Based Subunit Vaccines against Group A Streptococcus.

Project description:Peptide subunit vaccines hold great potential compared to traditional vaccines. However, peptides alone are poorly immunogenic. Therefore, it is of great importance that a vaccine delivery platform and/or adjuvant that enhances the immunogenicity of peptide antigens is developed. Here, we report the development of two different systems for the delivery of lipopeptide subunit vaccine (LCP-1) against group A streptococcus: polymer-coated liposomes and polyelectrolyte complexes (PECs). First, LCP-1-loaded and alginate/trimethyl chitosan (TMC)-coated liposomes (Lip-1) and LCP-1/alginate/TMC PECs (PEC-1) were examined for their ability to trigger required immune responses in outbred Swiss mice; PEC-1 induced stronger humoral immune responses than Lip-1. To further assess the adjuvanting effect of anionic polymers in PECs, a series of PECs (PEC-1 to PEC-5) were prepared by mixing LCP-1 with different anionic polymers, namely alginate, chondroitin sulfate, dextran, hyaluronic acid, and heparin, then coated with TMC. All produced PECs had similar particle sizes (around 200 nm) and surface charges (around + 30 mV). Notably, PEC-5, which contained heparin, induced higher antigen-specific systemic IgG and mucosal IgA titers than all other PECs. PEC systems, especially when containing heparin and TMC, could function as a promising platform for peptide-based subunit vaccine delivery for intranasal administration.

| S-EPMC7712447 | biostudies-literature

Saloplastic Macroporous Polyelectrolyte Complexes: Cartilage Mimics.

Project description:Complexes of sodium poly(4-styrenesulfonate) (NaPSS) and poly(diallyldimethylammonium chloride) (PDADMAC) were formed on mixing equimolar solutions in high salt concentration. Under ultracentrifugal fields, the complex precipitates were transformed into compact polyelectrolyte complexes (CoPECs), which showed extensive porosity. The mechanical properties of CoPECS make them attractive for bioimplants and tissue engineering applications. Free NaPSS chains in the closed pores of CoPECs create excess osmotic pressure, which controls the pore size and contributes to the mechanical resistance of the material. The mechanical properties of CoPECs, modulated by the ionic strength of the doping medium, were studied by uniaxial tensile testing and the stress-strain data were fit to a three-element Maxwell model which revealed at least two regimes of stress relaxation.

| S-EPMC2994323 | biostudies-literature

Polyelectrolyte-Coated Gold Nanoparticles: The Effect of Salt and Polyelectrolyte Concentration on Colloidal Stability.

Project description:Gold nanoparticles are widely used in biomedical applications. Their ease of surface modification, biocompatibility and the presence of surface plasmons makes them ideal tools for a variety of investigations. Polyelectrolyte-coated gold nanoparticles are employed in areas such as imaging, drug delivery and gene therapy; however, it is not well understood how different factors such as the polyelectrolyte and salt concentration affect the coating on the nanoparticles and hence their performance. Here, these parameters were systematically varied and their effect on the stability of the colloidal nanoparticle suspension was monitored. An increase in the polyelectrolyte concentration from 0 to 30 mg/mL led to a red shift of the surface plasmon peak and an increase in the zeta potential. Concentrations between 5 mg/mL and 30 mg/mL resulted in the most stable systems, with 1 mg/mL being the most unstable. Stable nanoparticle suspensions were formed in salt concentrations below 50 mM, while higher concentrations caused colloidal instability and irreversible aggregation.

| S-EPMC6402027 | biostudies-literature

Engineering Peptide-Based Polyelectrolyte Complexes with Increased Hydrophobicity.

Project description:Polyelectrolyte complexation is a versatile platform for the design of self-assembled materials. Here we use rational design to create ionic hydrophobically-patterned peptides that allow us to precisely explore the role of hydrophobicity on electrostatic self-assembly. Polycations and polyanions were designed and synthesized with an alternating sequence of d- and l-chiral patterns of lysine or glutamic acid with either glycine, alanine or leucine due to their increasing hydrophobicity index, respectively. Two motifs were considered for the oppositely charged patterned peptides; one with equal residues of charged and uncharged amino acids and the other with increased charge density. Mass spectroscopy, circular dichroism, H- and F-NMR spectroscopy were used to characterize the polypeptides. Polyelectrolyte complexes (PECs) formed using the sequences were characterized using turbidity measurements, optical microscopy and infrared spectroscopy. Our results show that the critical salt concentration, a key measure of PEC stability, increased with both increasing charge density as well as hydrophobicity. Furthermore, by increasing the hydrophobicity, the amount of PEC formed increased with temperature, contrary to purely ionic PECs. Lastly, we assessed the encapsulation behavior of these materials using a hydrophobic dye. Concluding that encapsulation efficiency increased with hydrophobic content of the complexes providing insight for future work on the application of these materials for drug delivery.

| S-EPMC6429441 | biostudies-literature

Compact polyelectrolyte complexes: "saloplastic" candidates for biomaterials.

Project description:Precipitates of polyelectrolyte complexes were transformed into rugged shapes suitable for bioimplants by ultracentrifugation in the presence of high salt concentration. Salt ions dope the complex, creating a softer material with viscous fluid-like properties. Complexes that were compacted under the centrifugal field (CoPECs) were made from poly(diallyldimethyl ammonium), PDADMA, as polycation, and poly(styrene sulfonate), PSS, or poly(methacrylic acid), PMAA, as polyanion. Dynamic mechanical testing revealed a rubbery plateau at lower frequencies for PSS/PDADMA with moduli that decreased with increasing salt concentration, as internal ion pair cross-links were broken. CoPECs had significantly lower modulii compared to similar polyelectrolyte complexes prepared by the "multilayering" method. The difference in mechanical properties was ascribed to higher water content (located in micropores) for the former and, more importantly, to their nonstoichiometric polymer composition. The modulus of PMAA/PDADMA CoPECs, under physiological conditions, demonstrated dynamic mechanical properties that were close to those of the nucleus pulposus in an intervertebral disk.

| S-EPMC2774624 | biostudies-other

Biocompatibility Studies of Gadolinium Complexes with Iminodiacetic Acid Derivatives.

Project description:Apart from using as radiopharmaceuticals, iminodiacetic acid derivatives, after complexation with gadolinium, have been also tested as MRI CAs (magnetic resonance imaging contrast agents) since they show high affinity to hepatocytes and therefore provide high-resolution MRI of the liver. The purpose of this study was to evaluate the biocompatibility of four gadolinium complexes with iminodiacetic acid (IDA) derivatives differing in substituent in aromatic ring by estimating their influence on plasma hemostasis, integrity of erythrocyte membrane, and toxicity towards human umbilical vein endothelial cells (HUVECs). The influence of gadolinium-based CAs on plasma hemostasis was evaluated by measuring PT (prothrombin time), APTT (activated partial tromboplastin time), and TT (thrombin time). The effects of tested compounds on RBCs (Red Blood Cells) were assessed using hemolysis assay and microscopy studies. The influence of gadolinium complexes on the barrier properties of HUVECs was assessed by means of real-time method based on the measurements of the impedance changes of the cells. Gadolinium complexes did not affect significantly PT and TT. APTT measurements revealed significant prolongation in the presence of all tested gadolinium complexes at the concentration higher than 0.5 ?mol/mL. Hemolysis assay showed that compounds with alkyl substituents in benzene ring without halogen atom (1-3) do not exert unfavorable effect on the integrity of erythrocyte membrane over the entire concentration range. All gadolinium complexes at 1.0 ?mol/mL contribute to the decrease in HUVEC viability and integrity. To conclude, the study describes biocompatibility studies of gadolinium-based CAs, provides additional insight into their potential toxicity associated with systemic administration, and underscores the necessity for further research.

| S-EPMC6469645 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data