Human Serum Albumin Nanoparticles for Use in Cancer Drug Delivery: Process Optimization and In Vitro Characterization

Amphiphilic Poly(ethylene glycol)-Cholesterol Conjugate: Stable Micellar Formulation for Efficient Loading and Effective Intracellular Delivery of Curcumin

A biodegradable and biocompatible micellar-based drug delivery system was developed using amphiphilic methoxy-poly(ethylene glycol)-cholesterol (C1) and poly(ethylene glycol)-S-S-cholesterol (C2) conjugates and applied to the tumoral release of the water-insoluble drug curcumin. These synthesized surfactants C1 and C2 were found to form stable micelles (CMC ∼ 6 μM) and an average hydrodynamic size of around 20-25 nm. The curcumin-encapsulated C1 micelle was formulated by a solvent evaporation method. A very high drug encapsulation efficiency (EE) of ∼88% and a drug loading (DL) capacity of ∼9% were determined for both the micelles. From the reduced rate of curcumin degradation and differential scanning calorimetry (DSC) analysis, the stability of the curcumin-loaded C1 micelle was found to be higher than that of the unloaded micelle, which confirmed a more compact structural arrangement in the presence of hydrophobic curcumin. A pH-sensitive release of curcumin (faster release with decrease in pH) was observed for the curcumin-loaded C1 micelle, attributed to the diffusion and relaxation/erosion of micellar aggregates. To achieve reduction environment-sensitive drug release, a disulfide (S-S) chemical linkage-incorporated mPEG-cholesterol conjugate (C2) was synthesized, which was found to show glutathione-responsive faster release of curcumin. The in vitro experiments carried out in SCC9 oral cancer cell lines showed that the blank C1 and C2 micelles were noncytotoxic at lower concentrations (<50 μM), while curcumin-loaded C1 and C2 micelles inhibited the proliferation and promoted the apoptosis. An increased in vitro cytotoxicity was observed for curcumin-loaded micelles compared to that of curcumin itself, demonstrating a better cell penetration efficacy of the micelle. These results were further supplemented by the in vivo anticancer analysis of the curcumin-loaded C1 and C2 micellar formulations using the mice xenograft model. Notably, curcumin-loaded C2 micelles showed a significantly stronger apoptotic effect in xenograft mice compared to curcumin-loaded C1 micelles, indicating the GSH environment-sensitive drug release and improved bioavailability. In conclusion, the mPEG-cholesterol C1 and C2 micellar system with the advantages of small size, high encapsulation efficiency, high drug loading, simple preparing technique, biocompatibility, and good in vitro and in vivo performance may have the potential to be used as a drug carrier for sustained and stimuli-responsive release of the hydrophobic drug curcumin.

The Neoteric Paradigm of Biomolecule-Functionalized Albumin-Based Targeted Cancer Therapeutics

Albumin is a nature-derived, versatile protein carrier, that has been explored extensively by researchers for anticancer drug delivery due to its role in enhancing drug stability, solubility, circulation time, targeting capabilities, and overall therapeutic efficacy. Albumin nanoparticles possess inherent biocompatibility, biodegradability, and passive tumor-targeting ability due to the enhanced permeability and retention effect. However, non-specific accumulation of cytotoxic agents in healthy tissues remains a challenge. In this paper, the functionalization of albumin nanoparticles using various biomolecules including antibodies, nucleic acids, proteins and peptides, vitamins, chondroitin sulfate, hyaluronic acid, and lactobionic acid have been discussed which enables specific recognition and binding to cancer cells. Furthermore, we highlight the supremacy of such a targeted approach in tumor-specific drug delivery, minimization of off-target effects, potential improvement in therapeutic efficacy, cellular internalization, reduced side effects, and better clinical outcomes. This review centers on how they have revolutionized the field of biomedical research and tuned into an excellent targeted approach. In conclusion, this review highlights in detail the role of albumin as a nanocarrier for tumor-targeted delivery using biomolecules as ligands.

89Zr-Labeled DFO@Durvalumab-HSA nanoparticles: In vitro potential for triple-negative breast cancer

This study presents the development and evaluation of a DFO@mAb-NP (DFO@Durvalumab-HSA-DTX nanoparticle) nanoplatform for imaging in triple-negative breast cancer (TNBC). The nanoplatform demonstrated significant changes postconjugation with DFO, evidenced by increased particle size from 178.1 ± 5 nm to 311 ± 26 nm and zeta potential alteration from -31.9 ± 3 mV to -40.5 ± 0.8 mV. Fourier-transform infrared spectroscopy and ultraviolet spectral analyses confirmed successful DFO conjugation, with notable shifts in peak wavelengths. High labeling efficiency was achieved with 89Zr, as indicated by thin layer radio chromatography and high-performance liquid radio chromatography results, with labeling efficiencies of 98 ± 2% for 89Zr-DFO@mAb and 96 ± 3% for 89Zr-DFO@mAb-NP. The nanoplatforms maintained stability over 24 h, showing less than 5% degradation. Lipophilicity assays revealed logP values of 0.5 ± 0.03 for 89Zr-DFO@mAb-NP and 0.98 ± 0.2 for 89Zr-DFO@mAb, indicating a higher lipophilic tendency in the radiolabeled Durvalumab. Cell uptake experiments showed an initial high uptake in MDA-MB-468 cells (45.1 ± 3.2%), which decreased over time, highlighting receptor-specific interactions. These comprehensive findings suggest the promising potential of the DFO@mAb-NP nanoplatform for targeted imaging in TNBC, with implications for improved diagnostic accuracy and treatment strategies.

Nano- and Micro-Platforms in Therapeutic Proteins Delivery for Cancer Therapy: Materials and Strategies

Proteins have emerged as promising therapeutics in oncology due to their great specificity. Many treatment strategies are developed based on protein biologics, such as immunotherapy, starvation therapy, and pro-apoptosis therapy, while some protein biologics have entered the clinics. However, clinical translation is severely impeded by instability, short circulation time, poor transmembrane transportation, and immunogenicity. Micro- and nano-particles-based drug delivery platforms are designed to solve those problems and enhance protein therapeutic efficacy. This review first summarizes the different types of therapeutic proteins in clinical and research stages, highlighting their administration limitations. Next, various types of micro- and nano-particles are described to demonstrate how they can overcome those limitations. The potential of micro- and nano-particles are then explored to enhance the therapeutic efficacy of proteins by combinational therapies. Finally, the challenges and future directions of protein biologics carriers are discussed for optimized protein delivery.

Bovine serum albumin-Camptothecin nanoparticles for RNAs packaging to improve the prognosis of Cancer

xRNAs have received a lot of attention for their potential in targeted therapy. This study aims to construct nanoparticles using bovine serum albumin (BSA) and Camptothecin to improve the bioavailability and targeting of drugs through RNA packaging, thereby improving the prognosis of cancer patients. The phacoemulsification method was used to synthesize BSA-CPT-NPs, and the single factor orthogonal design method was used to optimize the process. The cytotoxicity of nanoparticles to cancer cells and their effect on intracellular RNA expression were evaluated in vitro. The results showed that the formation of BSA-Camptothecin nanoparticles was uniform, and the drug loading and RNA encapsulation efficiency reached a high level. Cell experiments showed that the nanoparticle significantly inhibited the proliferation of cancer cells and enhanced the anti-tumor effect by regulating the expression of xRNAs. The study confirmed the potential of BSA-Camptothecin nanoparticles packaged by RNA to improve the efficiency and targeting of drug delivery, and future research will focus on further exploring its feasibility in clinical applications for cancer therapy.

Biomimetic nanoplatforms constructed from dialkylaminostyryl hetarene dyes and phospholipids exhibiting selective fluorescent response to specific proteins

The present work explores the specificity of supramolecular assemblies comprising dialkylaminostyrylhetarene dye molecules incorporated into phosphatidylcholine (PC) or phosphatidylserine (PS) aggregates. In PS-based assemblies, the dyes demonstrate a concentration-dependent fluorescent response, distinguishing anionic proteins such as bovine serum albumin (BSA) and pepsin from lysozyme (LYZ) in aqueous solutions. Conversely, no significant response is observed when the dyes are incorporated into the well-organized bilayers of neutral PC. The fluorescent response arises from the binding of dyes to proteins, leading to the detachment of dye molecules from the assemblies, rather than from the binding of proteins to the assemblies, although the latter process is facilitated by electrostatic attraction. Thus, both the poor ordering of PS molecules and the interfacial arrangement of the dyes are prerequisites for the fluorescent response of dye-PS aggregates. The structure of the dyes significantly impacts the spectral features of dye-PS and dye-protein assemblies. An optimal dye structure has been identified for the recognition of BSA, with a limit of detection (LOD) of 10.8 nM.

Aggregation of Albumins under Reductive Radical Stress

The reactions of radicals with human serum albumin (HSA) under reductive stress conditions were studied using pulse radiolysis and photochemical methods. It was proved that irradiation of HSA solutions under reductive stress conditions results in the formation of stable protein aggregates. HSA aggregates induced by ionizing radiation are characterized by unique emission, different from the UV emission of non-irradiated solutions. The comparison of transient absorption spectra and the reactivity of hydrated electrons (eaq-) with amino acids or HSA suggests that electron attachment to disulfide bonds is responsible for the transient spectrum recorded in the case of albumin solutions. The reactions of eaq- and CO2•- with HSA lead to the formation of the same products. Recombination of sulfur-centered radicals plays a crucial role in the generation of HSA nanoparticles, which are stabilized by intermolecular disulfide bonds. The process of creating disulfide bridges under the influence of ionizing radiation is a promising method for the synthesis of biocompatible protein nanostructures for medical applications. Our Raman spectroscopy studies indicate strong modification of disulfide bonds and confirm the aggregation of albumins as well. Low-temperature measurements indicate the possibility of electron tunneling through the HSA protein structure to specific CyS-SCy bridges. The current study showed that the efficiency of HSA aggregation depends on two main factors: dose rate (number of pulses per unit time in the case of pulse radiolysis) and the temperature of the irradiated solution.

Revolutionizing Alzheimer's treatment: Harnessing human serum albumin for targeted drug delivery and therapy advancements

Alzheimer's disease (AD) is a neurodegenerative disorder initiated by amyloid-beta (Aβ) accumulation, leading to impaired cognitive function. Several delivery approaches have been improved for AD management. Among them, human serum albumin (HSA) is broadly employed for drug delivery and targeting the Aβ in AD owing to its biocompatibility, Aβ inhibitory effect, and nanoform, which showed blood-brain barrier (BBB) crossing ability via glycoprotein 60 (gp60) receptor and secreted protein acidic and rich in cysteine (SPARC) protein to transfer the drug molecules in the brain. Thus far, there is no previous review focusing on HSA and its drug delivery system in AD. Hence, the reviewed article aimed to critically compile the HSA therapeutic as well as drug delivery role in AD management. It also delivers information on how HSA-incorporated nanoparticles with surfaced embedded ligands such as TAT, GM1, and so on, not only improve BBB permeability but also increase neuron cell targetability in AD brain. Additionally, Aβ and tau pathology, including various metabolic markers likely BACE1 and BACE2, etc., are discussed. Besides, the molecular interaction of HSA with Aβ and its distinctive forms are critically reviewed that HSA can segregate Zn(II) and Cu(II) metal ions from Aβ owing to high affinity. Furthermore, the BBB drug delivery challenges in AD are addressed. Finally, the clinical formulation of HSA for the management of AD is critically discussed on how the HSA inhibits Aβ oligomer and fibril, while glycated HSA participates in amyloid plaque formation, i.e., β-structure sheet formation. This review report provides theoretical background on HSA-based AD drug delivery and makes suggestions for future prospect-related work.

The multi-dimensional impact of captopril modification on human serum albumin

Captopril is a thiol drug, widely used for the management of hypertension and cardiovascular diseases. Reactive thiols are found to covalently modify the cysteines of plasma proteins and affect their structure and function. Human serum albumin (HSA) is prone to undergo modification by various low molecular weight compounds, including drugs. Cysteine34 (Cys34) in HSA has a free thiol group with antioxidant properties, considered to be the most redox-sensitive amino acid in plasma. Through mass-spectrometric analysis, we demonstrate for the first time that captopril forms a disulfide adduct at Cys34 residue and increases the protease susceptibility of HSA to trypsin. As evidenced by our biophysical and electron microscopy studies, HSA undergoes structural alteration, aggregation and morphological changes when treated with different captopril concentrations. Molecular dynamics studies further revealed the regions of secondary structural changes in HSA due to disulfide adduct formation by captopril at Cys34. It also elucidated the residues involved in the noncovalent interactions with captopril. It is envisaged that structural change in HSA may influence the efficacy of drug delivery as well as its own biological function. These findings may thus provide significant insights into the field of pharmacology intriguing further investigation into the effects of long-term captopril treatment.

Expanding Mn2+ loading capacity of BSA via mild non-thermal denaturing and cross-linking as a tool to maximize the relaxivity of water protons

Development of nanoparticles (NPs) serving as contrast enhancing agents in MRI requires a combination of high contrasting effect with the biosafety and hemocompatibility. This work demonstrates that bovine serum albumin (BSA) molecules bound to paramagnetic Mn2+ ions are promising building blocks of such NPs. The desolvation-induced denaturation of BSA bound with Mn2+ ions followed by the glutaraldehyde-facilitated cross-linking provides the uniform in size 102.0 ± 0.7 nm BSA-based nanoparticles (BSA-NPs) loaded with Mn2+ ions, which are manifested in aqueous solutions as negatively charged spheres with high colloid stability. The optimal loading of Mn2+ ions into BSA-NPs provides maximum values of longitudinal and transverse relaxivity at 98.9 and 133.6 mM-1 s-1, respectively, which are among the best known from the literature. The spin trap EPR method indicates that Mn2+ ions bound to BSA-NPs exhibit poor catalytic activity in the Fenton-like reaction. On the contrary, the presence of BSA-NPs has an antioxidant effect by preventing the accumulation of hydroxyl radicals produced by H2O2. The NPs exhibit remarkably low hemolytic activity and hemagglutination can be avoided at concentrations lower than 110 μM. Thus, BSA-NPs bound with Mn2+ ions are promising candidates for combining high contrast effect with biosafety and hemocompatibility.

Curcumin, its derivatives, and their nanoformulations: Revolutionizing cancer treatment

Curcumin is a natural compound derived from turmeric and can target malignant tumor molecules involved in cancer propagation. It has potent antioxidant activity, but its effectiveness is limited due to poor absorption and rapid elimination from the body. Various curcumin derivatives have also shown anticancer potential in in-vitro and in-vivo models. Curcumin can target multiple signaling pathways involved in cancer development/progression or induce cancer cell death through apoptosis. In addition, curcumin and its derivatives could also enhance the effectiveness of conventional chemotherapy, radiation therapy and reduce their associated side effects. Lately, nanoparticle-based delivery systems are being developed/explored to overcome the challenges associated with curcumin's delivery, increasing its overall efficacy. The use of an imaging system to track these formulations could also give beneficial information about the bioavailability and distribution of the nano-curcumin complex. In conclusion, curcumin holds significant promise in the fight against cancer, especially in its nanoform, and could provide precise delivery to cancer cells without affecting normal healthy cells.

A Novel ANG-BSA/BCNU/ICG MNPs Integrated for Targeting Therapy of Glioblastoma

PURPOSE

Develop an albumin nanoparticle-based nanoprobe for targeted glioblastoma (GBM) diagnosis and treatment, utilizing Angopep-2 for low-density lipoprotein receptor-related protein (LRP) targeting.

METHODS

Combined albumin-coated superparamagnetic iron oxide (SPIO), Carmustine (BCNU), and indocyanine green (ICG). Assessed morphology, size, Zeta potential, fluorescence, and drug encapsulation. Conducted in vitro fluorescence/MRI imaging and cell viability assays, and in vivo nanoprobe accumulation evaluation in brain tumors.

RESULTS

ANG-BSA/BCNU/ICG MNPs exhibited superior targeting and cytotoxicity against GBM cells in vitro. In vivo, enhanced brain tumor accumulation during imaging was observed.

CONCLUSION

This targeted imaging and drug delivery system holds promise for efficient GBM therapy and intraoperative localization, addressing Blood-brain barrier (BBB) limitations with precise drug delivery and imaging capabilities.

Triglyceride-filled albumin-based nanocapsules: A promising new system to avoid discarding poorly water-soluble drug candidates

Even though current drug discovery provides a variety of potential drug candidates, many of those substances are difficult to formulate due to their poor water-solubility. To overcome this obstacle a technological formulation is crucial. Albumin-based nanocarriers are a possible intravenous delivery system which is already approved and commercially available. However, no universal carrier for poorly water-soluble substances is found yet. In the present study, new preparation processes for nanocapsules consisting of a medium-chain triglyceride (MCT) core and a human serum albumin (HSA) shell were developed. The nanocarrier system exhibits desirable physicochemical properties with a hydrodynamic diameter of 150 nm and a polydispersity index of 0.1. Furthermore, the nanocapsules were stable towards the addition of electrolytes and also in basic to neutral pH range. The nanocapsules were storage stable for at least 7 months at 4 °C and could also be lyophilized to reach an even longer shelf life of at least 21 months. In addition, the nanocapsule system showed no cytotoxicity in cell culture. The developed system represents a suitable carrier for a variety of different poorly water-soluble drug substances (e.g., fenofibrate, naproxen, indomethacin) showing a high potential for a universal formulation platform for further lipophilic active pharmaceutical ingredients (APIs).

Radiolabeled Human Serum Albumin Nanoparticles Co-Loaded with Methotrexate and Decorated with Trastuzumab for Breast Cancer Diagnosis

Breast cancer is a leading cause of cancer-related mortality among women worldwide, with millions of new cases diagnosed yearly. Addressing the burden of breast cancer mortality requires a comprehensive approach involving early detection, accurate diagnosis, effective treatment, and equitable access to healthcare services. In this direction, nano-radiopharmaceuticals have shown potential for enhancing breast cancer diagnosis by combining the benefits of nanoparticles and radiopharmaceutical agents. These nanoscale formulations can provide improved imaging capabilities, increased targeting specificity, and enhanced sensitivity for detecting breast cancer lesions. In this study, we developed and evaluated a novel nano-radio radiopharmaceutical, technetium-99m ([99mTc]Tc)-labeled trastuzumab (TRZ)-decorated methotrexate (MTX)-loaded human serum albumin (HSA) nanoparticles ([99mTc]-TRZ-MTX-HSA), for the diagnosis of breast cancer. In this context, HSA and MTX-HSA nanoparticles were prepared. Conjugation of MTX-HSA nanoparticles with TRZ was performed using adsorption and covalent bonding methods. The prepared formulations were evaluated for particle size, PDI value, zeta (ζ) potential, scanning electron microscopy analysis, encapsulation efficiency, and loading capacity and cytotoxicity on MCF-7, 4T1, and MCF-10A cells. Finally, the nanoparticles were radiolabeled with [99mTc]Tc using the direct radiolabeling method, and cellular uptake was performed with the nano-radiopharmaceutical. The results showed the formation of spherical nanoparticles, with a particle size of 224.1 ± 2.46 nm, a PDI value of 0.09 ± 0.07, and a ζ potential value of -16.4 ± 0.53 mV. The encapsulation efficiency of MTX was found to be 32.46 ± 1.12%, and the amount of TRZ was 80.26 ± 1.96%. The labeling with [99mTc]Tc showed a high labeling efficiency (>99%). The cytotoxicity studies showed no effect, and the cellular uptake studies showed 97.54 ± 2.16% uptake in MCF-7 cells at the 120th min and were found to have a 3-fold higher uptake in cancer cells than in healthy cells. In conclusion, [99mTc]Tc-TRZ-MTX-HSA nanoparticles are promising for diagnosing breast cancer and evaluating the response to treatment in breast cancer patients.

Nanostructured proteins for delivering drugs to diseased tissues

During the last few years, nanostructures based on proteins have been playing a vital role in revolutionizing the nanomedicine era. Since protein nanoparticles are smaller and have a greater surface area, they retain a better capacity to interact with other molecules, resulting in carrying payloads efficiently to diseased tissues. Besides having attractive biocompatibility and biodegradability, protein nanoparticles can also be modified on their surfaces. For the fabrication of these nanostructures, there are several processes involved, including emulsification, desolvation, a combination of complex coacervation and electrospray. This can be achieved by using different proteins such as albumin, gelatin, elastin, gliadin, collagen, legumin and zein, as well as a combination of these proteins. It is possible to functionalize protein nanoparticles by altering their internal and external interfaces so that they can encapsulate drugs, release them in a controlled manner, disassemble them systematically and target tumors. This review highlights the physicochemical properties and engineering of several proteins to nano-dimensions used to deliver drugs to diseased tissues.

Dopamine-Conjugated Bovine Serum Albumin Nanoparticles Containing pH-Responsive Catechol-V(III) Coordination for In Vitro and In Vivo Drug Delivery

V(III) instead of commonly used Fe(III) provided a rich tris-catechol-metal coordination at pH 7.4, which is important for slow drug release at physiological pH. Bovine serum albumin (BSA) functionalized with catechol-containing dopamine (D) and cross-linked using tris-catechol-V(III) coordination yielded pH-responsive compact D-BSA NPs (253 nm). However, conversion to bis- and/or mono-catechol-V(III) complexes in an acidic medium resulted in degradation of NPs and rapid release of doxorubicin (DOX). It was shown that D-BSA NPs entered cancerous MCF-7 cells (66%) more efficiently than non-cancerous HEK293T (33%) in 3 h. Also, DOX-loaded NPs reduced cell viability of MCF-7 by 75% and induced apoptosis in a majority of cells after 24 h. Biodegradability and lack of hemolytic activity were shown in vitro, whereas a lack of toxicity was shown in histological sections of zebrafish. Furthermore, 30% of circulating tumor cells in vasculature in 24 h were killed by DOX-loaded NPs shown with the zebrafish CTC xenograft model.

Integrating Artificial Intelligence with Quality by Design in the Formulation of Lecithin/Chitosan Nanoparticles of a Poorly Water-Soluble Drug

The aim of the current study is to explore the potential of artificial intelligence (AI) when integrated with Quality by Design (QbD) approach in the formulation of a poorly water-soluble drug, for its potential use in carcinoma. Silymarin is used as a model drug for its potential effectiveness in liver cancer. A detailed QbD approach was applied. The effect of the critical process parameters was studied on each of the particle size, size distribution, and entrapment efficiency. Response surface designs were applied in the screening and optimization of lecithin/chitosan nanoparticles, to obtain an optimized formula. The release rate was tested, where artificial neural network models were used to predict the % release of the drug from the optimized formula at different time intervals. The optimized formula was tested for its cytotoxicity. A design space was established, with an optimized formula having a molar ratio of 18.33:1 lecithin:chitosan and 38.35 mg silymarin. This resulted in nanoparticles with a size of 161 nm, a polydispersity index of 0.2, and an entrapment efficiency of 97%. The optimized formula showed a zeta potential of +38 mV, with well-developed spherical particles. AI successfully showed high prediction ability of the drug's release rate. The optimized formula showed an enhancement in the cytotoxic effect of silymarin with a decreased IC50 compared to standard silymarin. Lecithin/chitosan nanoparticles were successfully formulated, with deep process and product understanding. Several tools were used as AI which could shift pharmaceutical formulations from experience-dependent studies to data-driven methodologies in the future.

Therapeutic applications of nanobiotechnology

Nanobiotechnology, as a novel and more specialized branch of science, has provided a number of nanostructures such as nanoparticles, by utilizing the methods, techniques, and protocols of other branches of science. Due to the unique features and physiobiological characteristics, these nanostructures or nanocarriers have provided vast methods and therapeutic techniques, against microbial infections and cancers and for tissue regeneration, tissue engineering, and immunotherapies, and for gene therapies, through drug delivery systems. However, reduced carrying capacity, abrupt and non-targeted delivery, and solubility of therapeutic agents, can affect the therapeutic applications of these biotechnological products. In this article, we explored and discussed the prominent nanobiotechnological methods and products such as nanocarriers, highlighted the features and challenges associated with these products, and attempted to conclude if available nanostructures offer any scope of improvement or enhancement. We aimed to identify and emphasize the nanobiotechnological methods and products, with greater prospect and capacity for therapeutic improvements and enhancements. We found that novel nanocarriers and nanostructures, such as nanocomposites, micelles, hydrogels, microneedles, and artificial cells, can address the associated challenges and inherited drawbacks, with help of conjugations, sustained and stimuli-responsive release, ligand binding, and targeted delivery. We recommend that nanobiotechnology, despite having few challenges and drawbacks, offers immense opportunities that can be harnessed in delivering quality therapeutics with precision and prediction. We also recommend that, by exploring the branched domains more rigorously, bottlenecks and obstacles can also be addressed and resolved in return.

Influence of Ionizing Radiation on Spontaneously Formed Aggregates in Proteins or Enzymes Solutions

We have shown that many proteins and enzymes (ovalbumin, β-lactoglobulin, lysozyme, insulin, histone, papain) undergo concentration-dependent reversible aggregation as a result of the interaction of the studied biomolecules. Moreover, irradiation of those protein or enzyme solutions under oxidative stress conditions results in the formation of stable soluble protein aggregates. We assume that protein dimers are mainly formed. A pulse radiolysis study has been made to investigate the early stages of protein oxidation by N3• or ^•OH radicals. Reactions of the N3• radical with the studied proteins lead to the generation of aggregates stabilized by covalent bonds between tyrosine residues. The high reactivity of the ^•OH with amino acids contained within proteins is responsible for the formation of various covalent bonds (including C-C or C-O-C) between adjacent protein molecules. In the analysis of the formation of protein aggregates, intramolecular electron transfer from the tyrosine moiety to Trp^• radical should be taken into account. Steady-state spectroscopic measurements with a detection of emission and absorbance, together with measurements of the dynamic scattering of laser light, made it possible to characterize the obtained aggregates. The identification of protein nanostructures generated by ionizing radiation using spectroscopic methods is difficult due to the spontaneous formation of protein aggregates before irradiation. The commonly used fluorescence detection of dityrosyl cross-linking (DT) as a marker of protein modification under the influence of ionizing radiation requires modification in the case of the tested objects. A precise photochemical lifetime measurement of the excited states of radiation-generated aggregates is useful in characterizing their structure. Resonance light scattering (RLS) has proven to be an extremely sensitive and useful technique to detect protein aggregates.

Explanation of inconsistencies in the determination of human serum albumin thermal stability

Thermal denaturation of human serum albumin has been the subject of many studies in recent decades, but the results of these studies are often conflicting and inconclusive. To clarify this, we combined different spectroscopic and calorimetric techniques and performed an in-depth analysis of the structural changes that occur during the thermal unfolding of different conformational forms of human serum albumin. Our results showed that the inconsistency of the results in the literature is related to the different quality of samples in different batches, methodological approaches and experimental conditions used in the studies. We confirmed that the presence of fatty acids (FAs) causes a more complex process of the thermal denaturation of human serum albumin. While the unfolding pathway of human serum albumin without FAs can be described by a two-step model, consisting of subsequent reversible and irreversible transitions, the thermal denaturation of human serum albumin with FAs appears to be a three-step process, consisting of a reversible step followed by two consecutive irreversible transitions.

Cisplatin and Albumin-Based Gold-Cisplatin Nanoparticles Enhance Ablative Radiation Therapy-Induced Antitumor Immunity in Local and Distant Tumor Microenvironment

PURPOSE

Ablative radiation therapy (RT) is an important strategy to eliminate primary tumor and can potentially induce the abscopal effect. Human serum albumin nanoparticle (NP) was used for controlled release of cisplatin to decrease cisplatin's systemic toxicity, and gold (Au) was added to increase RT-induced immunogenic cell death and potentiate the abscopal antitumor immunity.

METHODS AND MATERIALS

The designed albumin-based cisplatin-conjugated AuNPs were administered concurrently with ablative RT. C57BL/6 mice implanted with syngeneic murine Lewis lung carcinoma or murine MB49 tumor models were treated with ablative RT (12 Gy per fraction for 2 fractions, total 24 Gy), cisplatin, or Au-cisplatin NPs.

RESULTS

Combining ablative RT with cisplatin or Au-cisplatin NPs both destroyed the primary tumor effectively and elicited immunogenic cell death accompanied by release of danger-associated molecular patterns. This enhanced recruitment of effector tumor-infiltrating immune cells, including natural killer T cells and CD8+ T cells, and elicited an increased percentage of professional antigen-presenting CD11c+ dendritic cells. Transient weight loss, accompanying hepatotoxicity, nephrotoxicity, and hematopoietic suppression, was observed as a systemic adverse event in the cisplatin but not the Au-cisplatin NPs group. Cisplatin and Au-cisplatin NPs both showed equivalent ability to reduce metastatic potential when combined with ablative RT, confirmed by suppressed unirradiated flank tumor growth and decreased metastatic lung tumor burden, which translated to improved survival. Mobilization and abundance of effector tumor-infiltrating immune cells including CD8+ T cells and dendritic cells were observed in the distant lung tumor microenvironment after ablative RT with cisplatin or Au-cisplatin NPs, demonstrating increased antitumor immunotherapeutic activity as an abscopal effect.

CONCLUSIONS

Compared with cisplatin, the albumin-based Au-cisplatin NPs exhibited equivalent but no superior antitumor immunotherapeutic activity while reducing systemic adverse events and can be safely administered concurrently with ablative RT. Alternative NP formulations may be designed to further improve anticancer outcomes.

Photodynamic therapy: Innovative approaches for antibacterial and anticancer treatments

Photodynamic therapy is an alternative treatment mainly for cancer but also for bacterial infections. This treatment dates back to 1900 when a German medical school graduate Oscar Raab found a photodynamic effect while doing research for his doctoral dissertation with Professor Hermann von Tappeiner. Unexpectedly, Raab revealed that the toxicity of acridine on paramecium depends on the intensity of light in his laboratory. Photodynamic therapy is therefore based on the administration of a photosensitizer with subsequent light irradiation within the absorption maxima of this substance followed by reactive oxygen species formation and finally cell death. Although this treatment is not a novelty, there is an endeavor for various modifications to the therapy. For example, selectivity and efficiency of the photosensitizer, as well as irradiation with various types of light sources are still being modified to improve final results of the photodynamic therapy. The main aim of this review is to summarize anticancer and antibacterial modifications, namely various compounds, approaches, and techniques, to enhance the effectiveness of photodynamic therapy.

Effect of folate-targeted Erlotinib loaded human serum albumin nanoparticles on tumor size and survival rate in a rat model of glioblastoma

The aim of this study was to prepare folate-targeted Erlotinib loaded human serum albumin nanoparticles (FA-ERL-HSA NPs) and investigate in vitro cytotoxic and apoptotic effects using cell lines (U87MG and C6 cells) and an in vivo rat bearing C6 glioma model. The mean size of the FA-ERL-HSA NPs prepared using a desolvation method was 135 nm. In vitro MTT assays demonstrated that FA-ERL-HSA NPs had an IC₅₀ value of 52.18 μg/mL and 17.53 μg/mL compared to free ERL which had an IC₅₀ value of 119.8 μg/mL and 103.2 μg/mL for U87MG and C6 cells for 72 h, respectively. Flow cytometry results showed the apoptosis rate with FA-ERL-HSA NPs (100 μg/mL, 72 h) was higher compared to free ERL for both U87MG and C6 cells. Experiments using a rat glioblastoma model via TUNEL assay indicated that the apoptosis index of FA-ERL-HSA NPs was 48 % compared to 21 % for free ERL and the tumor size effectively decreased after a daily injection of 220 μg (2.5 mg/kg) from 87.45 mm³ (19th day) to 1.28 mm³ (60th day). The median survival rate of the rats increased after treatment to >100 days which was greater than controls.

Recent Patents and Potential Applications of Homogenisation Techniques in Drug Delivery Systems

BACKGROUND

The term homogenise means "to force or provide coalesce". Homogenisation is a process to attain homogenous particle size. The objective of the homogenisation process is to use fluid force to split the fragments or tiny particles contained in the fluids into very small dimensions and form a sustainable dispersion suitable for further production.

METHODS

The databases were collected through Scopus, google patent, science web, google scholar, PubMed on the concept of homogenisation. The data obtained were systematically investigated.

RESULTS

The present study focus on the use of the homogenisation in drug delivery system. The aim of homogenisation process is to achieve the particle size in micro-and nano- range as it affects the different parameters in the formulation and biopharmaceutical profile of the drug. The particle size reduction plays a key role in influencing drug dissolution and absorption. The reduced particle size enhances the stability and therapeutic efficacy of the drug. Homogenization technology ensures to achieve effective, clinically efficient and targeted drug delivery with the minimal side effect.

CONCLUSION

Homogenization technology has been shown to be an efficient and easy method of size reduction to increase solubility and bioavailability, stability of drug carriers. This article gives an overview of the process attributes affecting the homogenization process, the patenting of homogeniser types, design, the geometry of valves and nozzles and its role in drug delivery.

Risk-Assessment-Based Optimization Favours the Development of Albumin Nanoparticles with Proper Characteristics Prior to Drug Loading

Albumin nanocarrier research and development is a challenging area in the field of personalized medicine and in providing advanced therapeutic solutions. Albumin as a biocompatible, nonimmunogenic, and non-toxic protein carrier that can be exploited to conjugate drugs with poor bioavailability to improve on this feature. With many different perspectives and desired target profiles, a systematic structural approach must be used in nanoparticle development. The extended Research and Development (R&D) Quality by Design thinking and methodology proved to be useful in case of specific nanoparticle development processes before. However, the coacervation method is the most frequently applied preparation method for HSA nanoparticles; there is a lack of existing research work which has directly determined the influence of process parameters, control strategy, or design space. With a quality-management-driven strategy, a knowledge space was developed for these versatile nanoparticles and an initial risk assessment was conducted on the quality-affecting factors regarding the coacervation method, followed by an optimization process via Plackett–Burman and Box–Behnken experimental design. As a result of screening the effect of process variables on the fabrication of HSA nanoparticles, an optimized colloidal drug delivery system was engineered with desired nanoparticulate properties.

Nanocarriers as a Delivery Platform for Anticancer Treatment: Biological Limits and Perspectives in B-Cell Malignancies

Nanoparticle-based therapies have been proposed in oncology research using various delivery methods to increase selectivity toward tumor tissues. Enhanced drug delivery through nanoparticle-based therapies could improve anti-tumor efficacy and also prevent drug resistance. However, there are still problems to overcome, such as the main biological interactions of nanocarriers. Among the various nanostructures for drug delivery, drug delivery based on polymeric nanoparticles has numerous advantages for controlling the release of biological factors, such as the ability to add a selective targeting mechanism, controlled release, protection of administered drugs, and prolonging the circulation time in the body. In addition, the functionalization of nanoparticles helps to achieve the best possible outcome. One of the most promising applications for nanoparticle-based drug delivery is in the field of onco-hematology, where there are many already approved targeted therapies, such as immunotherapies with monoclonal antibodies targeting specific tumor-associated antigens; however, several patients have experienced relapsed or refractory disease. This review describes the major nanocarriers proposed as new treatments for hematologic cancer, describing the main biological interactions of these nanocarriers and the related limitations of their use as drug delivery strategies.

The evaluation of anticancer activity by synthesizing 5FU loaded albumin nanoparticles by exposure to UV light

In this study, as a new synthesis method, UV light was employed as a type of cross-linking agent to control drug storage and to produce nanoparticles of different sizes and to stabilize the nanoparticles for the first time. We showed that the exposure time of the 5FU albumin solution to UV light produces differences in the size and characterization of the nanoparticles and also produces different cytotoxic effects on MCF-7 breast cancer cells. While the 5FU-A1 nanoparticles we synthesized with 1 h UV storage were approximately 43 nm, the 5FU-A2 nanoparticles we synthesized with UV storage for 3 h increased to an average of 300 nm. 5FU-A1 (IC₅₀ value: 2.5 μg/mL) was approximately 16 times more cytotoxic than free 5FU (IC₅₀ value 39.39 μg/mL) on MCF-7 cancer cells. Moreover, when normal HUVEC cells are treated with 5FU-A1 at a concentration of 2.5 μg/mL, more than 80% of these normal cells remain viable. In addition, we examined the rate of early-to-late apoptosis and necrosis in MCF-7 cancer cells using the Annexin V/PI flow cytometry assay. According to our results, 5FU-A1 promoted the apoptosis pathway. Finally, we examined P-gp activity with MDR1/ABCB1 antibody by flow cytometry and Rhodamine123 with fluorescent dye.

Nanomaterial Probes for Nuclear Imaging

Nuclear imaging is a powerful non-invasive imaging technique that is rapidly developing in medical theranostics. Nuclear imaging requires radiolabeling isotopes for non-invasive imaging through the radioactive decay emission of the radionuclide. Nuclear imaging probes, commonly known as radiotracers, are radioisotope-labeled small molecules. Nanomaterials have shown potential as nuclear imaging probes for theranostic applications. By modifying the surface of nanomaterials, multifunctional radio-labeled nanomaterials can be obtained for in vivo biodistribution and targeting in initial animal imaging studies. Various surface modification strategies have been developed, and targeting moieties have been attached to the nanomaterials to render biocompatibility and enable specific targeting. Through integration of complementary imaging probes to a single nanoparticulate, multimodal molecular imaging can be performed as images with high sensitivity, resolution, and specificity. In this review, nanomaterial nuclear imaging probes including inorganic nanomaterials such as quantum dots (QDs), organic nanomaterials such as liposomes, and exosomes are summarized. These new developments in nanomaterials are expected to introduce a paradigm shift in nuclear imaging, thereby creating new opportunities for theranostic medical imaging tools.

Design of Targeted Flurbiprofen Biomimetic Nanoparticles for Management of Arthritis: In Vitro and In Vivo Appraisal

Flurbiprofen (FLUR) is a potent non-steroidal anti-inflammatory drug used for the management of arthritis. Unfortunately, its therapeutic effect is limited by its rapid clearance from the joints following intra-articular injection. To improve its therapeutic efficacy, hyaluronic acid-coated bovine serum albumin nanoparticles (HA-BSA NPs) were formulated and loaded with FLUR to achieve active drug targeting. NPs were prepared by a modified nano-emulsification technique and their HA coating was proven via turbidimetric assay. Physicochemical characterization of the selected HA-BSA NPs revealed entrapment efficiency of 90.12 ± 1.06%, particle size of 257.12 ± 2.54 nm, PDI of 0.25 ± 0.01, and zeta potential of -48 ± 3 mv. The selected formulation showed in-vitro extended-release profile up to 6 days. In-vivo studies on adjuvant-induced arthritis rat model exhibited a significant reduction in joint swelling after intra-articular administration of FLUR-loaded HA-BSA NPs. Additionally, there was a significant reduction in CRP level in blood as well as TNF-α, and IL-6 levels in serum and joint tissues. Immunohistochemical study indicated a significant decrease in iNOS level in joint tissues. Histopathological analysis confirmed the safety of FLUR-loaded HA-BSA NPs. Thus, our results reveal that FLUR loaded HA-BSA NPs have a promising therapeutic effect in the management of arthritis.

Optimization and Development of Selective Histone Deacetylase Inhibitor (MPT0B291)-Loaded Albumin Nanoparticles for Anticancer Therapy

Histone deacetylase (HDAC) inhibitors have emerged as a new class of antitumor agent for various types of tumors. MPT0B291, a novel selective inhibitor of HDAC6, demonstrated significant antiproliferative activity in various human cancer cell types. However, MPT0B291 has very low water solubility, which limits its clinical use for cancer therapy. In the current study, MPT0B291 was encapsulated in human serum albumin (HSA), and its anticancer activities were investigated. Nanoparticles (NPs) were prepared using two-stage emulsification resulting in 100~200-nm NPs with a fine size distribution (polydispersity index of <0.3). The in vitro drug release profiles of MPT0B291-loaded HSA NPs presented sustained-release properties. The cytotoxic effect on MIA PaCa-2 human pancreatic carcinoma cells was found to be similar to MPT0B291-loaded HSA NPs and the free-drug group. The albumin-based formulation provided a higher maximum tolerated dose than that of a drug solution with reduced toxicity toward normal cells. Furthermore, in vivo pharmacokinetic studies demonstrated an effective increase (5~8-fold) in the bioavailability of NPs containing MPT0B291 loaded in HSA compared to the free-drug solution with an extended circulation time (t_1/2) leading to significantly enhanced efficacy of anticancer treatment.

Synthesis and characterization of peptide conjugated human serum albumin nanoparticles for targeted cardiac uptake and drug delivery

Congestive heart failure, a prominent cardiovascular disease results primarily from myocardial infarction or ischemia. Milrinone (MRN), a widely used clinical drug for heart failure, improves myocardial contractility and cardiac function through its inotropic and vasodilatory effects. However, lacking target specificity, it exhibits low bioavailability and lower body retention time. Therefore, in this study, angiotensin II (AT1) peptide conjugated human serum albumin nanoparticles (AT1-HSA-MRN-NPs) have been synthesized for targeted delivery of MRN to the myocardium, overexpressing AT1 receptors under heart failure. The NPs were surface functionalized through a covalent conjugation reaction between HSA and AT1. Nanoparticle size was 215.2±4.7 nm and zeta potential -28.8±2.7 mV and cumulative release of MRN was ~72% over 24 hrs. The intracellular uptake of nanoparticles and cell viability was studied in H9c2 cells treated with AT1-MRN-HSA-NPs vs the control non-targeted drug, MRN Lactate under normal, hypoxic and hypertrophic conditions. The uptake of AT1-HSA-MRN-NPs in H9c2 cells was significantly higher as compared to non-targeted nanoparticles, and the viability of H9c2 cells treated with AT1-MRN-HSA-NPs vs MRN Lactate was 73.4±1.4% vs 44.9±1.4%, respectively. Therefore, AT1-HSA-MRN-NPs are safe for in vivo use and exhibit superior targeting and drug delivery characteristics for treatment of heart failure.

Piperine for treating breast cancer: A review of molecular mechanisms, combination with anticancer drugs, and nanosystems

Piperine (PIP) is an alkaloid found primarily in Piper longum, and this natural compound has been shown to exert effects on proliferation and survival against various types of cancer. In particular, PIP has potent inhibitory effects on breast cancer (BC), the most prevalent type of cancer in women worldwide. PIP targets numerous signaling pathways associated with the therapy of BC cells through the following mechanisms: (a) induction of arrest of the cell cycle and apoptosis; (b) alteration of the signaling protein expression; (c) reduction in transcription factors; and (d) inhibition of tumor growth. BC cells have the ability to resist conventional drugs, so one of the strategies is the combination of PIP with other phytochemicals such as paclitaxel, thymoquinone, hesperidin, bee venom, tamoxifen, mitoxantrone, piperlongumin, and curcumin. Nanotechnology-based drug encapsulation systems are currently used to enhance the release of PIP. This includes polymer nanoparticles, carbon nanotubes, and liposomes. In the present review, the chemistry and bioavailability of PIP, its molecular targets in BC, and nanotechnological strategies are discussed. Future research directions are also discussed to further understand this promising natural product.

Albumin Nanoparticle Formulation for Heart-Targeted Drug Delivery: In Vivo Assessment of Congestive Heart Failure

Congestive heart failure is a fatal cardiovascular disease resulting in tissue necrosis and loss of cardiac contractile function. Inotropic drugs such as milrinone are commonly used to improve the myocardial contractility and heart function. However, milrinone is associated with severe side effects and lower circulation time. In this article, a novel protein nanoparticle formulation for heart-targeted delivery of milrinone has been designed and tested. The formulation was prepared using albumin protein conjugated with the targeting ligand, angiotensin II peptide to form nanoparticles following the ethanol desolvation method. The formulation was characterized for size, charge, and morphology and tested in a rat model of congestive heart failure to study pharmacokinetics, biodistribution, and efficacy. The overall cardiac output parameters were evaluated comparing the formulation with the control non-targeted drug, milrinone lactate. This formulation exhibited improved pharmacokinetics with a mean retention time of 123.7 min, half-life of 101.3 min, and clearance rate of 0.24 L/(kg*h). The targeted formulation also significantly improved ejection fraction and fractional shortening parameters thus improving cardiac function. This study demonstrates a new approach in delivering inotropic drugs such as milrinone for superior treatment of congestive heart failure.

Functionalized Particles Designed for Targeted Delivery

Pure bioactive compounds alone can only be exceptionally administered in medical treatment. Usually, drugs are produced as various forms of active compounds and auxiliary substances, combinations assuring the desired healing functions. One of the important drug forms is represented by a combination of active substances and particle-shaped polymer in the nano- or micrometer size range. The review describes recent progress in this field balanced with basic information. After a brief introduction, the paper presents a concise overview of polymers used as components of nano- and microparticle drug carriers. Thereafter, progress in direct synthesis of polymer particles with functional groups is discussed. A section is devoted to formation of particles by self-assembly of homo- and copolymer-bearing functional groups. Special attention is focused on modification of the primary functional groups introduced during particle preparation, including introduction of ligands promoting anchorage of particles onto the chosen living cell types by interactions with specific receptors present in cell membranes. Particular attention is focused on progress in methods suitable for preparation of particles loaded with bioactive substances. The review ends with a brief discussion of the still not answered questions and unsolved problems.

Cross-linked Histone as a Nanocarrier for Gut Delivery of Hydrophobic Cargos

Delivering hydrophobic molecules through the intestine can be challenging due to limited cargo solubility and the harsh biochemical environment of the stomach. Here, we show that a protein-based nanocarrier system based on the abundant protein histone and the natural cross-linker genipin can deliver hydrophobic cargos, such as dyes and therapeutic molecules, through the gastrointestinal tract. Using hydrophobic near-infrared dyes as model cargos, a panel of potential protein carriers was screened, and histone was identified as the one with the best loading capability. The resulting nanoparticles had a positive ζ potential and were mucoadhesive. Cross-linking of the amine-rich nanocarrier with genipin was particularly effective relative to other proteins and increased the stability of the system during incubation with pepsin. Cross-linking was required for successful delivery of a hydrophobic dye to the colon of mice after oral gavage. To assess the platform for therapeutic delivery, another hydrophobic model compound, curcumin, was delivered using cross-linked histone nanoparticles in a murine colitis model and significantly alleviated the disease. Taken together, these results demonstrate that histone is a cationic, mucoadhesive, and cross-linkable protein nanocarrier that can be considered for oral delivery.

Recent Advances in Curcumin Treated Non-Small Cell Lung Cancers: An Impetus of Pleiotropic Traits and Nanocarrier Aided Delive ry

Characterized by the abysmal 18% five year survival chances, non-small cell lung cancers (NSCLCs) claim more than half of their sufferers within the first year of being diagnosed. Advances in biomedical engineering and molecular characterization have reduced the NSCLC diagnosis via timid screening of altered gene expressions and impaired cellular responses. While targeted chemotherapy remains a major option for NSCLCs complications, delayed diagnosis, and concurrent multi-drug resistance remain potent hurdles in regaining normalcy, ultimately resulting in relapse. Curcumin administration presents a benign resolve herein, via simultaneous interception of distinctly expressed pathological markers through its pleiotropic attributes and enhanced tumor cell internalization of chemotherapeutic drugs. Studies on NSCLC cell lines and related xenograft models have revealed a consistent decline in tumor progression owing to enhanced chemotherapeutics cellular internalization via co-delivery with curcumin. This presents an optimum readiness for screening the corresponding effectiveness in clinical subjects. Curcumin is delivered to NSCLC cells either (i) alone, (ii) in stoichiometrically optimal combination with chemotherapeutic drugs, (iii) through nanocarriers, and (iv) nanocarrier co-delivered curcumin and chemotherapeutic drugs. Nanocarriers protect the encapsulated drug from accidental and non-specific spillage. A unanimous trait of all nanocarriers is their moderate drug-interactions, whereby native structural expressions are not tampered. With such insights, this article focuses on the implicit NSCLC curative mechanisms viz-a-viz, free curcumin, nanocarrier delivered curcumin, curcumin + chemotherapeutic drug and nanocarrier assisted curcumin + chemotherapeutic drug delivery.

Towards a microfluidics platform for the continuous manufacture of organic and inorganic nanoparticles

In the last decade, microfluidics has opened new avenues for the synthesis of nanomaterials. However, the adoption of this production technique has been limited to a few high-value, low-production-volume organic nanoparticles. While there are several technical factors that can be attributed to this slow adoption, an important aspect to consider is the lack of a unified platform capable of producing a wide range of nanomaterials. In this work, we highlight a micro-mixing platform that can manufacture both organic and in-organic nanoparticles over a wide size range (nm-μm). We show that the platform can predictably and reproducibly create size and shape-controlled formulations with high homogeneity through input flow parameters. We further explore parallelization of this platform and discuss key technical constraints for high-volume production. We believe that the platform presented in this work can accelerate the adoption of nanomaterials relevant to a range of industries that encompass pharmaceutics, diagnostics, and cosmeceuticals.

Preparation Optimization of Bovine Serum Albumin Nanoparticles and Its Application for siRNA Delivery

BACKGROUND

siRNA brings hope for cancer therapy. However, there are many obstacles for application of siRNA in clinical. Because of the excellent biocompatibility, non-toxicity and non-immunogenicity of bovine serum albumin (BSA), BSA-based nanoparticles have been widely designed as a drug carrier system.

METHODS

The optimal formula for BSA NPs preparation was investigated by central composite design response surface methodology (CCD-RSM), BSA-based survivin-siRNA delivery system (BSA NPs/siRNA) was characterized by dynamic light scattering, atomic force microscope, transmission electron microscope and Bradford method. The in vitro anti-tumor effect and mechanism of BSA NPs were investigated by confocal microscopic imaging, MTT assay, RT-qPCR and ELISA analysis. Moreover, the anti-tumor effect, distribution and biosafety of BSA NPs were studied in vivo.

RESULTS

The optimal formula for BSA NPs was settled to be 20 mg/mL for BSA concentration, 9 for pH value, 136% for crosslinking degree and 1.6 mL/min for speed of ethanol addition. BSA NPs/siRNA could remain stable at 4°C for 4 weeks and protect siRNA from degradation by RNase A. Besides, BSA NPs/siRNA could maintain a sustained release of siRNA and promote the uptake of siRNA significantly. The survivin-mRNA level and the survivin-protein level were decreased by 55% ± 1.6% and 54% ± 1.6% separately. The in vivo tumor inhibition results suggested that the tumor inhibition rate of BSA NPs/siRNA-treated group was 54% ± 12% and was similar with that of DOX-treated group (57% ± 9.2%, P > 0.05). The biosafety results confirmed that BSA NPs/siRNA could not induce significant damages to the main organs and blood in vivo.

CONCLUSION

These results demonstrated that CCD-RSM was an effective tool for preparation analysis, and the BSA NPs/siRNA was a promising system for siRNA-based gene therapy.

Applications of serum albumins in delivery systems: Differences in interfacial behaviour and interacting abilities with polysaccharides

One of the major applications of Serum Albumins is their use as delivery systems for lipophilic compounds in biomedicine. Their biomedical application is based on the similarity with Human Serum Albumin (HSA), as a fully biocompatible protein. In general, Bovine Serum Albumin (BSA) is treated as comparable to its human homologue and used as a model protein for fundamental studies since it is available in high amounts and well understood. This protein can act as a carrier for lipophilic compounds or as protective shell in an emulsion-based vehicle. Polysaccharides are generally included in these formulations in order to increase the stability and/or applicability of the carrier. In this review, the main biomedical applications of Albumins as drug delivery systems are first presented. Secondly, the differences between BSA and HSA are highlighted, exploring the similarities and differences between these proteins and their interaction with polysaccharides, both in solution and adsorbed at interfaces. Finally, the use of Albumins as emulsifiers for emulsion-based delivery systems, concretely as Liquid Lipid Nanocapsules (LLNs), is revised and discussed in terms of the differences encountered in the molecular structure and in the interfacial properties. The specific case of Hyaluronic Acid is considered as a promising additive with important applications in biomedicine. The literature works are thoroughly discussed highlighting similarities and differences between BSA and HSA and their interaction with polysaccharides encountered at different structural levels, hence providing routes to control the optimal design of delivery systems.

Measuring the concentration of protein nanoparticles synthesized by desolvation method: Comparison of Bradford assay, BCA assay, hydrolysis/UV spectroscopy and gravimetric analysis

The desolvation technique is one of the most popular methods for preparing protein nanoparticles for medicine, biotechnology, and food applications. We fabricated 11 batches of BSA nanoparticles and 2 batches of gelatin nanoparticles by desolvation method. BSA nanoparticles from 2 batches were cross-linked by heating at +70 °C for 2 h; other nanoparticles were stabilized by glutaraldehyde. We compared several analytical approaches to measuring their concentration: gravimetric analysis, bicinchoninic acid assay, Bradford assay, and alkaline hydrolysis combined with UV spectroscopy. We revealed that the cross-linking degree and method of cross-linking affect both Bradford and BCA assay. Direct measurement of protein concentration in the suspension of purified nanoparticles by dye-binding assays can lead to significant (up to 50-60%) underestimation of nanoparticle concentration. Quantification of non-desolvated protein (indirect method) is affected by the presence of small nanoparticles in supernatants and can be inaccurate when the yield of desolvation is low. The reaction of cross-linker with protein changes UV absorbance of the latter. Therefore pure protein solution is an inappropriate calibrator when applying UV spectroscopy for the determination of nanoparticle concentration. Our recommendation is to determine the concentration of protein nanoparticles by at least two different methods, including gravimetric analysis.

TAT-modified serum albumin nanoparticles for sustained-release of tetramethylpyrazine and improved targeting to spinal cord injury

BACKGROUND

Spinal Cord injury (SCI) is a kind of severe traumatic disease. The inflammatory response is a significant feature after SCI. Tetramethylpyrazine (TMP), a perennial herb of umbelliferae, is an alkaloid extracted from ligustici. TMP can inhibit the production of nitric oxide and reduce the inflammatory response in peripheral tissues. It can be seen that the therapeutic effect of TMP on SCI is worthy of affirmation. TMP has defects such as short half-life and poor water-solubility. In addition, the commonly used dosage forms of TMP include tablets, dropping pills, injections, etc., and its tissue and organ targeting is still a difficult problem to solve. To improve the solubility and targeting of TMP, here, we developed a nanotechnology-based drug delivery system, TMP-loaded nanoparticles modified with HIV trans-activator of transcription (TAT-TMP-NPs).

RESULTS

The nanoparticles prepared in this study has integrated structure. The hemolysis rate of each group is less than 5%, indicating that the target drug delivery system has good safety. The results of in vivo pharmacokinetic studies show that TAT-TMP-NPs improves the bioavailability of TMP. The quantitative results of drug distribution in vivo show that TAT-TMP-NPs is more distributed in spinal cord tissue and had higher tissue targeting ability compared with other treatment groups.

CONCLUSIONS

The target drug delivery system can overcome the defect of low solubility of TMP, achieve the targeting ability, and show the further clinical application prospect.

Analysis on the interaction and binding properties of daphnoretin and human serum albumin in the presence of cisplatin: multi-spectroscopic methods and docking simulation

The interaction between anticancer drugs and HSA may have a significant impact on the pharmacology and efficacy of drugs. Drugs change the binding properties of HSA by regulating the quenching mechanism, binding mode and binding affinity. In this study, the interactions of cisplatin (cDDP), HSA, and daphnoretin were elucidated by multi-spectroscopic analyses and docking simulation. Fluorescence quenching showed that cDDP could not change the static quenching mechanism of HSA-daphnoretin, but could enhance their binding affinity. Site competition experiments revealed that daphnoretin and cDDP both bound to site I, which was consistent with the results of molecular docking. Thermodynamic date indicated that cDDP and daphnoretin formed a more stable complex with HSA via hydrophobic, van der Waals interaction and hydrogen bond. Three-dimensional fluorescence and circular dichroism spectra showed that cDDP changed the conformation and micro-environment of HSA induced by daphnoretin. This work could provide valuable information for the binding properties and interaction among cDDP, daphnoretin and HSA, and put forward the possibility of using HSA as a multidrug carrier.