HSA Nanoparticles Research Articles

A simple improved desolvation method for the rapid preparation of albumin nanoparticles

The current study tried to establish a simple and fast method for the preparation of BSA and HSA nanoparticles, based on an improved desolvation procedure under the aspect of a controllable particle size around 100nm for drug delivery applications. The Procedure used for the nanoparticles preparation was simplified by using a designed apparatus for controlling the addition of ethanol and it was used instead of conventional tubing pump which enabled the preparation of nanoparticles under defined conditions. By using EDC as cross-linker instead of glutharaldehyde, the time of nanoparticles preparation procedure was reduced to 3h. Several factors of the preparation process, such as the volume of the albumin solution, desolvating agent volume, the amount of cross-linker, the presence of salts and protein concentration were evaluated. Nanoparticles with smaller size were obtained under experimental conditions without the presence of salts or the use of buffers, 250mg of protein/4ml water, 5mg cross-linker, the addition of 4 and 8ml ethanol by using the designed apparatus to the HSA and BSA solution, respectively. By using this improved method, BSA and HSA nanoparticles of the size around 100nm and polydispersity below 0.2 were obtained.

Doxorubicin-loaded nanoparticles consisted of cationic- and mannose-modified-albumins for dual-targeting in brain tumors

Albumin nanoparticles have been increasingly viewed as an effective way of delivering chemotherapeutics to solid tumors. Here, we report the one-pot development of a unique prototype of doxorubicin-loaded nanoparticles (NPs) made of naïve albumin (HSA) plus cationic- (c-HSA) or mannose-modified-albumin (m-HSA), with the goal of traversing the blood–brain barrier and targeting brain tumors. c-HSA was synthesized by conjugating ethylenediamine to naïve HSA. Then, m-HSA was derivatized using mannopyranoside via a thiol-maleimide reaction. The c/m-HSA NPs were prepared using a mixture solution of c- and m-HSAs in deionized water and doxorubicin in ethanol/chloroform in the same pot using a high-pressure homogenizer. The c/m-HSA NPs were spherical and well-dispersed, with a particle size of 90.5±3.1nm and zeta-potential of −12.0±0.3mV at c- and m-HSA feed ratios of 5% and 10%, respectively. The c/m-HSA NPs displayed good stability over 3days based on particle size and a linear gradual doxorubicin release over 2days. Specifically, the inhibitory concentration (IC50; 0.5±0.02μg/ml) of c/m-HSA NPs was >2.2–15.6 fold lower than those of doxorubicin or the other HSA NPs. Moreover, among HSA NPs, c/m-HSA NPs exhibited the most prominent performances in transport across the bEnd.3 cell monolayer and uptake in bEnd.3 cells as well as U87MG glioblastoma cells and spheroids. Furthermore, c/m-HSA NPs were localized to a greater extent in brain glioma compared to naïve HSA NPs. Orthotopic glioma-bearing mice treated with c/m-HSA NPs displayed significantly smaller tumors than the mice treated with saline, doxorubicin or HSA NPs. This improved anti-glioma efficacy seemed to be due to the dual-enhanced system of dual cationic absorptive transcytosis and glucose-transport by the combined use of c- and m-HSAs. The c/m-HSA NPs have potential as a novel anti-brain cancer agent with good targetability.

Preparation of albumin based nanoparticles for delivery of fisetin and evaluation of its cytotoxic activity

Fisetin is a well known flavonoid that shows several properties such as antioxidant, antiviral and anticancer activities. Its use in the pharmaceutical field is limited due to its poor aqueous solubility which results in poor bioavailability and poor permeability. The aim of our present study is to prepare fisetin loaded human serum albumin nanoparticles to improve its bioavailability. The nanoparticles were prepared by a desolvation method and characterized by spectroscopic and microscopic techniques. The particles were smooth and spherical in nature with an average size of 220±8nm. The encapsulation efficiency was found to be 84%. The in vitro release profile showed a biphasic pattern and the release rate increases with increase in ionic strength of solution. We have also confirmed the antioxidant activity of the prepared nanoparticles by a DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. Further its anticancer activity was evaluated using MCF-7 breast cancer cell lines. Our findings suggest that fisetin loaded HSA nanoparticles could be used to transfer fisetin to target areas under specific conditions and thus may find use as a delivery vehicle for the flavonoid.

Preparation of imatinib base loaded human serum albumin for application in the treatment of glioblastoma

IMTb loaded HSA nanoparticles were prepared using a desolvation method at different pH and the encapsulation efficiency and drug loading capacity were tested.

Self-assembly of plasma protein through disulfide bond breaking and its use as a nanocarrier for lipophilic drugs

A disulfide bond breaking strategy used to fabricate HSA nanoparticles with dithiothreitol as the reducing agent is presented. The hydrophobic interaction is a dominating factor in the assembly process. These nanoparticles are suitable lipophilic drug delivery systems, which have significant tumor-targeting capabilities.

Paclitaxel loaded human serum albumin nanoparticles stabilized with intermolecular disulfide bonds

A self-cross-link strategy was adopted to form inter-protein disulfide crosslinks with albumin's own thiol groups. PTX was further entrapped non-covalently in the HSA matrix to form paclitaxel loaded HSA nanoparticles (PTX-HSA-NPs).

A Novel Self-Assembly Albumin Nanocarrier for Reducing Doxorubicin-Mediated Cardiotoxicity

Doxorubicin is an antitumor drug commonly used against a wide spectrum of tumors. However, the clinical application of DOX is restricted by its cardiotoxicity. To reduce the cardiotoxicity, we develop an albumin-based nanocarrier via a new molecular switch method for DOX delivery. Spherically shaped DOX-loaded HSA nanoparticles (NPs-DOX) are prepared with a drug-loading capacity and particle size of 4.3% and 120.1 ± 26 nm, respectively. In vivo studies demonstrate that NPs-DOX is able to preferentially accumulate in tumor and show great tumor inhibition on H22 hepatocellular-carcinoma-bearing mice. As for the toxicity, compared with free DOX, the maximum tolerated dose of NPs-DOX is increased from 10 to over 30 mg/kg, indicating the reduced systematic toxicity. More importantly, the cardiotoxicity induced by NPs-DOX is also significantly reduced because both left ventricular ejection fraction and left ventricular fractional shortening are almost not changed and other cardiotoxicity markers such as serum creatine kinase-MB, lactate dehydrogenase, superoxide dismutase, and malonaldehyde are kept constant. The reduced cardiotoxicity of NPs-DOX is also confirmed by nonhistological changes in the heart tissue. Therefore, such albumin-based nanocarrier can be one of the most promising strategies for the delivery of DOX.

Human serum albumin (HSA) nanoparticles stabilized with intermolecular disulfide bonds

We have presented a self-cross-link strategy to fabricate HSA nanoparticles using a desolvation method. The nanoparticles were stabilized by intermolecular disulfide bonds while still dissolvable in reducing media. The fabrication process does not involve any toxic chemicals and hence the nanoparticles may be useful as a drug carrier.

Trastuzumab decorated methotrexate–human serum albumin conjugated nanoparticles for targeted delivery to HER2 positive tumor cells

Targeted drug delivery systems could reduce the systemic toxicity of anticancer drugs following cancer chemotherapy. In this study we developed methotrexate–human serum albumin conjugated nanoparticles (MTX–HSA NPs) which were surface decorated using trastuzumab (TMAB) molecules. The size of TMAB–MTX–HSA NPs was between 123 and 346nm according to the amount of TMAB molecules conjugated on their surfaces. The cytotoxicity of TMAB–MTX–HSA NPs on HER2 positive cells after 24h was significantly higher than that for non-targeted MTX–HSA NPs and also free MTX. However when the number of attached TMAB molecules was very high, the cytotoxicity of TMAB–MTX–HSA NPs was similar to the cytotoxicity of non-targeted MTX–HSA NPs approximately. There were no significant differences between cytotoxicity of TMAB–MTX–HSA NPs and MTX–HSA NPs for HER2 negative cells after 24h. The results of flow cytometry analysis showed that the binding activity of TMAB molecules remained approximately unchanged after conjugation, if the number of the attached TMAB molecules on the surface of MTX–HSA NPs was not very high. Moreover, TMAB–MTX–HSA NPs showed higher uptake to HER2 positive cells compared to non-targeted MTX–HSA NPs when the optimized amount of TMAB was conjugated on the surface of NPs. In conclusion, conjugation of TMAB molecules on the MTX conjugated HSA nanoparticles is an appropriate method for active tumor targeting of MTX.

The in vivo antitumor activity of LHRH targeted methotrexate–human serum albumin nanoparticles in 4T1 tumor-bearing Balb/c mice

The use of targeted drug delivery systems is a growing trend in cancer treatment to decrease the adverse effect of anti-cancer drugs. In this study, we sought to conjugate methotrexate–human serum albumin nanoparticles (MTX–HSA NPs) with luteinizing-hormone releasing hormone (LHRH). The LHRH was intended to target LHRH receptors overexpressed on the several types of tumors. The expression of LHRH receptors on the 4T1 breast cancer cells was confirmed by FITC conjugated LHRH receptor antibody using fluorescence microscopy. Female Balb/c mice bearing 4T1 breast cancer tumor were treated with a single i.v. injection of free MTX, non-targeted MTX–HSA NPs and LHRH targeted MTX–HSA NPs. LHRH targeted MTX–HSA nanoparticles showed stronger anti-tumor activity in vivo. By 7 days after treatment, average tumor volume in the LHRH targeted MTX–HSA NPs treated group decreased to 8.67% of the initial tumor volume when the number of attached LHRH molecules on MTX–HSA NPs was the highest, while the average tumor volume in non-targeted MTX–HSA NPs treated mice grew rapidly and reached 250.7% of the initial tumor volume 7 days after the treatment. LHRH targeted MTX–HSA NPs could significantly extend the survival time of tumor bearing mice compared with the non-targeted MTX–HSA NPs and free MTX formulations.

Novel photosensitizer-protein nanoparticles for Photodynamic therapy: Photophysical characterization and in vitro investigations

In this work two types of pheophorbide-HSA (Pheo-HSA) nanoparticles, PHSA40 and PHSA100, were prepared and their photophysical and photosensitizing properties were investigated. Due to intramolecular interactions the singlet oxygen quantum yield of PHSA40 and PHSA100 is very low (less than 0.1). Intracellular uptake and phototoxicity of pheophorbide a as well as of the Pheo-HSA nanoparticles were studied in Jurkat cells. The HSA nanoparticles do not influence the amount of dye accumulation in cells. After 24 h incubation, PHSA40 and PHSA100 showed a higher phototoxicity than Pheo. The reason for this behavior is an efficient nanoparticle decomposition in the cellular lysosomes. The process of drug release during incubation of cells with Pheo-HSA nanoparticles was illustrated by fluorescence lifetime imaging (FLIM) and confocal laser scanning microscopy (CLSM). The final phototoxicity of Pheo-HSA is at the same scale as induced by free Pheo. The drug release ability of HSA nanoparticles shows the possibility to use such formulations as drug carriers in PDT treatment. Therefore, this work constructs a standard for further investigation and optimization of photosensitizer-HSA drug carrier system.

Effect of trastuzumab-modified antisense oligonucleotide-loaded human serum albumin nanoparticles prepared by heat denaturation

Nanoparticles represent a promising tool for targeted drug delivery to tumour cells and are able to protect drugs against degradation. In our present study we developed targeted nanoparticles loaded with antisense oligonucleotides (ASOs) against Plk1 (polo-like kinase 1) prepared by heat denaturation instead of using glutaraldehyde. Glutaraldehyde can lead to an inactivation of ASOs through chemical crosslinking and is a toxic entity. We examined the ideal preparation conditions and characterised the resulting particles in terms of physico-chemical properties, ASO recovery after enzymatic degradation and stability. Stable monodisperse nanoparticles with an ASO recovery of more than 80% could be prepared at a temperature of 105 °C for 10 min. Furthermore we performed quantitative real-time PCR and Western blot to detect an ASO-mediated effect on Plk1 in BT-474 cells. We observed a significant reduction of Plk1 mRNA and protein expression. Thus, this is the first report of ASO-loaded HSA nanoparticles prepared by heat denaturation, where an impact on gene expression could be observed. The data provide the basis for the further development of carrier systems for ASOs to reduce off-target effects evoked by systemically administered ASOs and to achieve a better penetration into primary and metastatic target cells.

Preparation and characterisation of rose Bengal-loaded surface-modified albumin nanoparticles

Surface-modified albumin nanoparticles were prepared from two poly(ethylene glycol)–human serum albumin conjugates: poly(thioetheramido acid)–poly(ethylene glycol) copolymer-grafted HSA (HSA–PTAAC–PEG) and methoxy poly(ethylene glycol)-grafted HSA (HSA–mPEG). Rose bengal (RB) was used as a model drug for encapsulation into the nanoparticles either during the particle production or by adsorption post particle preparation. The drug incorporation and release was affected by the different production methods and the different polymer compositions. When RB was loaded in HSA and HSA/HSA–PTAAC–PEG nanoparticles, up to 5% (w/w) drug content was achieved. The drug loading in HSA–mPEG nanoparticles was much lower and the results from the microcalorimetry study indicated that the low loading efficiency was due to less drug–protein binding sites available in the HSA–mPEG molecule as compared to the HSA molecule. The release of RB from the albumin nanoparticles was very slow in PBS and dramatically accelerated in the presence of trypsin. Compared with unmodified nanoparticles, the slower release of RB from the surface-modified HSA nanoparticles in the presence of the enzyme suggested that the existence of a steric hydrophilic barrier on the surface of the nanoparticles made digestion of the nanoparticles more difficult.