Novel ionically crosslinked casein nanoparticles for flutamide delivery: formulation, characterization, and in vivo pharmacokinetics

An Up-to-date Review on Protein-based Nanocarriers in the Management of Cancer

BACKGROUND

A big health issue facing the world's population is cancer. An alarming increase in cancer patients was anticipated by worldwide demographic statistics, which showed that the number of patients with different malignancies was rapidly increasing. By 2025, probably 420 million cases were projected to be achieved. The most common cancers diagnosed are breast, colorectal, prostate, and lung. Conventional treatments, such as surgery, chemotherapy, and radiation therapy, have been practiced.

OBJECTIVE

In recent years, the area of cancer therapy has changed dramatically with expanded studies on the molecular-level detection and treatment of cancer. Recent advances in cancer research have seen significant advances in therapies such as chemotherapy and immunotherapy, although both have limitations in effectiveness and toxicity.

METHODS

The development of nanotechnology for anticancer drug delivery has developed several potentials as nanocarriers, which may boost the pharmacokinetic and pharmacodynamic effects of the drug product and substantially reduce the side effects.

RESULTS

The advancement in non-viral to viral-based protein-based nanocarriers for treating cancer has earned further recognition in this respect. Many scientific breakthroughs have relied on protein-based nanocarriers, and proteins are essential organic macromolecules for life. It allows targeted delivery of passive or active tumors using non-viral-based protein-based nanocarriers to viral-based protein nanocarriers. When targeting cancer cells, both animal and plant proteins may be used in a formulation process to create self-assembled viruses and platforms that can successfully eradicate metastatic cancer cells.

CONCLUSION

This review, therefore, explores in depth the applications of non-viral to viral proteinbased noncarriers with a specific focus on intracellular drug delivery and anti-cancer drug targeting ability.

Casein-Based Nanoparticles: A Potential Tool for the Delivery of Daunorubicin in Acute Lymphocytic Leukemia

The aim of this study was to develop casein-based nanoscale carriers as a potential delivery system for daunorubicin, as a pH-responsive targeting tool for acute lymphocytic leukemia. A coacervation technique followed by nano spray-drying was used for the preparation of drug-loaded casein nanoparticles. Four batches of drug-loaded formulations were developed at varied drug-polymer ratios using a simple coacervation technique followed by spray-drying. They were further characterized using scanning electron microscopy, dynamic light scattering, FTIR spectroscopy, XRD diffractometry, and differential scanning calorimetry. Drug release was investigated in different media (pH 5 and 7.4). The cytotoxicity of the daunorubicin-loaded nanoparticles was compared to that of the pure drug. The influence of the polymer-to-drug ratio on the nanoparticles' properties such as their particle size, surface morphology, production yield, drug loading, entrapment efficiency, and drug release behavior was studied. Furthermore, the cytotoxicity of the drug-loaded nanoparticles was investigated confirming their potential as carriers for daunorubicin delivery.

A comparative evaluation of anti-tumor activity following oral and intravenous delivery of doxorubicin in a xenograft model of breast tumor

Purpose

Natural materials have been extensively studied for oral drug delivery due to their biodegradability and other unique properties. In the current research, we fabricated sodium caseinate nanomicelles (NaCNs) using casein as a natural polymer to develop a controlled-release oral delivery system that would improve the therapeutic potential of doxorubicin (DOX) and reduce its toxicity.

Methods

DOX-loaded NaCNs were synthesized and thoroughly characterized, then subjected to in vivo anti-tumor evaluation and bio-distribution analysis in a 4T1-induced breast cancer model.

Results

Our findings indicated that the tumor would shrink by eight-fold in the group orally treated with DOX-NaCNs when compared to free DOX. The tumor accumulated drug 1.27-fold more from the orally administered DOX-NaCNs compared to the intravenously administered DOX-NaCNs, 6.8-fold more compared to free DOX, and 8.34-times more compared to orally administered free DOX. In comparison, the orally administered DOX-NaCNs lead to a significant reduction in tumor size (5.66 ± 4.36 mm3) compared to intravenously administered DOX-NaCNs (10.29 ± 4.86 mm3) on day 17 of the experiment. NaCNs were well tolerated at a single dose of 2000 mg/kg in an acute oral toxicity study.

Conclusion

The enhanced anti-tumor effects of oral DOX-NaCNs might be related to the controlled release of DOX from the delivery system when compared to free DOX and the intravenous formulation of DOX-NaCNs. Moreover, NaCNs is recognized as a safe and non-toxic delivery system with excellent bio-distribution profile and high anti-tumor effects that has a potential for oral chemotherapy.

Engineering biomolecular systems: Controlling the self-assembly of gelatin to form ultra-small bioactive nanomaterials

The size of nanocarriers determines the biological property of the materials, especially as it relates to intratumoral distribution. Previous research has shown that sizes of 10–50 nm penetrate deep inside the tumor, resulting in better efficacy. On the other hand, studies have shown that gelatin exhibits excellent biological properties, including compatibility, degradability, and toxicity. Therefore, FDA approved gelatin as a safe material to use as an excipient in injectables. The bottleneck is the nonexistence of smaller-sized gelatin nanoparticles (GNPs) to realize the full potential of these biomaterials. Yet, GNPs with sizes of less than 50 nm have not been reported; the synthetic strategy reported in the literature uses “uncontrolled crosslinking coupled with nanoprecipitation”, resulting in larger particle size. We have developed a new method to self-assemble gelatin strands by using an anionic, phosphate-based crosslinker and controlled precipitation. The method we developed produced ultra-small gelatin nanoparticles (G^X) of size 10 nm with a high degree of reproducibility, and it was characterized using dynamic light scattering (DLS), Energy-dispersive X-ray spectroscopy (EDS), High-resolution transmission, and scanning electron microscopy (HR-TEM/STEM). We also explored G^X as a bioactive platform to encapsulate imaging and therapy agents within the cavity. Interestingly, we were able to encapsulate 2 nm size gold nanoparticles within the void of G^X. The versatile nature of the G^X particles was further demonstrated by surface functionalizing with larger size gelatin nanoparticles to form core-satellite nanocomposites. Additionally, we studied the tumor penetrability of dye-tagged 10, 50, and 200 nm gelatin nanoparticles. The study showed that smaller size gelatin nanoparticles penetrate deeper tumor regions than larger particles. In general, G^X was efficient in penetrating the inner region of the spheroids. The results demonstrate the potential capabilities of ultra-small G^X nanoparticles for multi-staged payload delivery, diagnostics, and cancer therapy.

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Synthesized 10 nm-size gelatin nanoparticles (G^X) using controlled self-assembly process.

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G^X was used as a platform to encapsulate imaging and therapeutic agents. In addition, smaller size gold nanoparticles also were encapsulated.

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The surface of G^X was used to attach with gold or larger size gelatin nanoparticles.

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Using tumor spheroids, we demonstrated that G^X show enhanced enhancedtumor penetrability.

Casein Microgels as Benzydamine Hydrochloride Carriers for Prolonged Release

This research aims to investigate the properties of nano- and micro-sized casein hydrogels crosslinked by sodium tripolyphosphate as drug delivery systems. Benzydamine hydrochloride was chosen as a model hydrophilic drug. The gels were synthesized by varying different parameters: casein concentration, casein/crosslinking ratio, and addition of ethanol as a co-solvent. The electrostatic attractive interactions between the casein and the sodium tripolyphosphate were confirmed by FTIR spectroscopy. The particle sizes was determined by dynamic light scattering and varied in the range between several hundred nanometers and several microns. The yield of the gelation process was high for all investigated samples and varied between 55.3% and 78.3%. The encapsulation efficiency of the particles was strongly influenced by the casein concentration and casein/crosslinker ratio and its values were between 4.6% and 22.4%. The release study confirmed that casein particles are useful as benzydamine carriers and ensured prolonged release over 72 h.

Nano Milk Protein-Mucilage Complexes: Characterization and Anticancer Effect

The anticancer activity of natural compounds has recently attracted multidisciplinary research. In this study, the complexation of milk proteins (MP) with Isabgol husk mucilage (IHM) and Ziziphus spina-christi mucilage (NabM) was investigated. In this context, the physicochemical properties of milk protein mucilage complexes (MPMC) including pH, Carr's index, water solubility, and water absorption indices were measured, and the flow behavior was studied. In addition, the amino acid profile, protein digestibility, and phenolic and flavonoids content of MPMC were explored, and the microstructure of the complexes was visualized using transmission electron microscopy. The antioxidant and anticancer potencies of MPMC against two cancerous cell lines, human liver cancer HEPG-2 and breast cancer MCF-7, in comparison with two normal cell lines, namely, Bj-1 and MCF-12F, were tested using neutral red uptake assay. The results revealed that MPMC had scavenging activity against DPPH, ABTS, and HS radicals. Moreover, MPMC has the potential to prevent DNA damage induced by oxidative stress in Type-Fenton's reaction. The results of the neutral red assay showed significant growth inhibition of both HEPG-2, MCF-7, whereas no significant cytotoxic effect was detected against Bj-1 and MCF-12F. RT-qPCR results indicated MPMC stimulated apoptosis as revealed by the upregulation of the pro-apoptosis gene markers Casepase-3, p53, Bax. Meanwhile, the anti-apoptosis Bcl-2 gene was downregulated. However, no significant difference was observed in normal cell lines treated with MPMC. In conclusion, MPMC can be considered as a promising anticancer entity that can be used in the development of novel cancer therapeutics with comparable activity and minimal side effects compared to conventional cancer chemotherapies.

Cholesterol-Based Nanovesicles Enhance the In Vitro Cytotoxicity, Ex Vivo Intestinal Absorption, and In Vivo Bioavailability of Flutamide

Critical adverse effects and frequent administration, three times per day, limit the use of flutamide (FLT) as a chemotherapeutic agent in the treatment of prostate cancer. Therefore, our research aimed to develop new cholesterol-based nanovesicles for delivering FLT to malignant cells in an endeavor to maximize its therapeutic efficacy and minimize undesired adverse effects. Draper–Lin small composite design was used to optimize the critical quality attributes of FLT-loaded niosomes and ensure the desired product quality. The influence of the selected four independent variables on mean particle size (Y₁), zeta potential (Y₂), drug entrapment efficiency (Y₃), and the cumulative drug release after 24 h (Y₄) was examined. The optimized nanovesicles were assessed for their in vitro cytotoxicity, ex-vivo absorption via freshly excised rabbit intestine as well as in vivo pharmacokinetics on male rats. TEM confirmed nanovescicles’ spherical shape with bilayer structure. Values of dependent variables were 748.6 nm, −48.60 mV, 72.8% and 72.2% for Y₁, Y₂, Y₃ and Y₄, respectively. The optimized FLT-loaded niosomes exerted high cytotoxic efficacy against human prostate cancer cell line (PC-3) with an IC₅₀ value of 0.64 ± 0.04 µg/mL whilst, it was 1.88 ± 0.16 µg/mL for free FLT. Moreover, the IC₅₀ values on breast cancer cell line (MCF-7) were 0.27 ± 0.07 µg/mL and 4.07 ± 0.74 µg/mL for FLT-loaded niosomes and free FLT, respectively. The permeation of the optimized FLT-loaded niosomes through the rabbit intestine showed an enhancement ratio of about 1.5 times that of the free FLT suspension. In vivo pharmacokinetic study displayed an improvement in oral bioavailability of the optimized niosomal formulation with AUC and C_max values of 741.583 ± 33.557 μg/mL × min and 6.950 ± 0.45 μg/mL compared to 364.536 ± 45.215 μg/mL × min and 2.650 ± 0.55 μg/mL for the oral FLT suspension. With these promising findings, we conclude that encapsulation of FLT in cholesterol-loaded nanovesicles enhanced its anticancer activity and oral bioavailability which endorse its use in the management of prostate cancer.

Alginate-based microparticles structured with different biopolymers and enriched with a phenolic-rich olive leaves extract: A physico-chemical characterization

Encapsulation of olive leaves extracts (OLE), rich of healthy components like Oleuropein, Hydroxytyrosol and Verbascoside, represents a new challenge to improve stability and nutritional value of food as well as a way to recover value added compounds from by-products, contributing to a more sustainable food system. In this context, OLE-loaded microbeads of Na alginate alone or in combination with Pectin, Na Caseinate or Whey protein isolates, were produced by emulsification internal ionotropic gelation. Encapsulation efficiency of the main phenolic compounds (Oleuropein, Hydroxytyrosol, Verbascoside) was carried out along with microparticles morphological characterization by scanning electron microscopy (SEM), thermal properties by differential scanning calorimetry (DSC) and color. Encapsulation efficiency resulted higher for Alginate/Pectin, whilst Alginate/Caseinate was the less performing system, probably due to the lower interaction with polyphenols. SEM revealed collapsed structures and continuous smooth surfaces for Alginate and Alginate/Pectin microbeads while more regular structures and porous surfaces were observed for Alginate/Caseinate and Alginate/Whey proteins. Higher hue angle and lower chroma values were observed for all the beads with respect to the pure extract, indicating a reduction of the yellow/brown color. DSC highlighted higher thermal stability for the microbeads in comparison to the original ingredients, showing also new thermal transitions related to bonds formation between polymers and OLE.

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Verbascoside showed higher encapsulation efficiency compared to Oleuropein.

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Alginate/Pectin was the most efficient system for encapsulation purposes.

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Microstructural traits were linked to the encapsulation efficiency.

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Thermal analysis revealed increased thermal stability of encapsulated polyphenols.

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Encapsulation allowed a mitigation of the color properties of the olive leaf extract.

Utilization of diverse protein sources for the development of protein-based nanostructures as bioactive carrier systems: A review of recent research findings (2010-2021)

Consumer awareness of the relationship between health and nutrition has caused a substantial increase in the demand for nutraceuticals and functional foods containing bioactive compounds (BACs) with potential health benefits. However, the direct incorporation of many BACs into commercial food and beverage products is challenging because of their poor matrix compatibility, chemical instability, low bioavailability, or adverse impact on food quality. Advanced encapsulation technologies are therefore being employed to overcome these problems. In this article, we focus on the utilization of plant and animal derived proteins to fabricate micro and nano-particles that can be used for the oral delivery of BACs such as omega-3 oils, vitamins and nutraceuticals. This review comprehensively discusses different methods being implemented for fabrications of protein-based delivery vehicles, types of proteins used, and their compatibility for the purpose. Finally, some of the challenges and limitations of different protein matrices for encapsulation of BACs are deliberated upon. Various approaches have been developed for the fabrication of protein-based microparticles and nanoparticles, including injection-gelation, controlled denaturation, and antisolvent precipitation methods. These methods can be used to construct particle-based delivery systems with different compositions, sizes, surface hydrophobicity, and electrical characteristics, thereby enabling them to be used in a wide range of applications.

pH-driven entrapment of enrofloxacin in casein-based nanoparticles for the enhancement of oral bioavailability

Enrofloxacin (ENR), a broad-spectrum antibacterial drug, has extremely poor water solubility contributing to low bioavailability, which prevents drug formulation design and limits its wide application in livestock farming and aquaculture. Compared to conventional formulations of ENR, casein (Cas)-based drug delivery system has been reported to have significant advantages in the improvement of solubility and bioavailability of drugs. In this paper, we report the preparation process of ENR-loaded Cas nanoparticles (ENR-Cas) using magnetic agitation without any organic agent and the optimization of the formulation. Transmission electron microscopy (TEM), dynamic light scattering (DLS), differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), and Fourier transform infrared spectroscopy (FTIR) were all adopted to characterize the ENR-Cas. Results showed that the obtained ENR-Cas were approximately spherical with a particle size of 171.6 ± 13.8 nm with a polydispersity index of 0.322 ± 0.053. In vitro release behavior of ENR-Cas showed a sustained release profile. Additionally, in vivo study in rats displayed that the mean plasma concentration of ENR after oral administration of ENR-Cas was significantly higher than that treated with ENR suspension. The mean residence time (MRT0-24) of ENR was enhanced by Cas nanoparticles from 9.287 ± 0.524 to 11.372 ± 1.139 hr in comparison with ENR suspension. Accordingly, the area under the curve (AUC0-24) of ENR-Cas was 80.521 ± 6.624 μg·hr/ml, 3.8-fold higher than that of ENR suspension (20.850 ± 1.715 μg·hr/ml). Therefore, it can be concluded that ENR-Cas enhanced the absorption, prolonged the retention time, and improved oral bioavailability of ENR. Taken the good oral safety of Cas into consideration, ENR-Cas should be a more promising oral preparation of ENR for clinical application.

Interventional NIR Fluorescence Imaging of Cancer: Review on Next Generation of Dye-Loaded Protein-Based Nanoparticles for Real-Time Feedback During Cancer Surgery

The use of fluorescence imaging technique for visualization, resection and treatment of cancerous tissue, attained plenty of interest once the promise of whole body and deep tissue near-infrared (NIR) imaging emerged. Why is NIR so desired? Contrast agents with optical properties in the NIR spectral range offer an upgrade for the diagnosis and treatment of cancer, by dint of the deep tissue penetration of light in the NIR region of the electromagnetic spectrum, also known as the optical window in biological tissue. Thus, the development of a new generation of NIR emitting and absorbing contrast agents able to overcome the shortcomings of the basic free dye administration is absolutely essential. Several examples of nanoparticles (NPs) have been successfully implemented as carriers for NIR dye molecules to the tumour site owing to their prolonged blood circulation time and enhanced accumulation within the tumour, as well as their increased fluorescence signal relative to free fluorophore emission and active targeting of cancerous cells. Due to their versatile structure, good biocompatibility and capability to efficiently load dyes and bioconjugate with diverse cancer-targeting ligands, the research area of developing protein-based NPs encapsulated or conjugated with NIR dyes is highly promising but still in its infancy. The current review aims to provide an up-to-date overview on the biocompatibility, specific targeting and versatility offered by protein-based NPs loaded with different classes of NIR dyes as next-generation fluorescent agents. Moreover, this study brings to light the newest and most relevant advances involving the state-of-the-art NIR fluorescent agents for the real-time interventional NIR fluorescence imaging of cancer in clinical trials.

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.

Optimization and Formulation of Nanostructured and Self-Assembled Caseinate Micelles for Enhanced Cytotoxic Effects of Paclitaxel on Breast Cancer Cells

BACKGROUND

Paclitaxel (PTX) is a widely used anti-cancer drug for treating various types of solid malignant tumors including breast, ovarian and lung cancers. However, PTX has a low therapeutic response and is linked with acquired resistance, as well as a high incidence of adverse events, such as allergic reactions, neurotoxicity and myelosuppression. The situation is compounded when its complex chemical structure contributes towards hydrophobicity, shortening its circulation time in blood, causing off-target effects and limiting its therapeutic activity against cancer cells. Formulating a smart nano-carrier may overcome the solubility and toxicity issues of the drug and enable its more selective delivery to the cancerous cells. Among the nano-carriers, natural polymers are of great importance due to their excellent biodegradability, non-toxicity and good accessibility. The aim of the present research is to develop self-assembled sodium caseinate nanomicelles (NaCNs) with PTX loaded into the hydrophobic core of NaCNs for effective uptake of the drug in cancer cells and its subsequent intracellular release.

METHODS

The PTX-loaded micelle was characterized with high-performance liquid chromatography (HPLC), Fourier Transform Infrared Spectra (FTIR), High Resolution-Transmission Electron Microscope (HR-TEM), Field Emission Scanning Electron Microscope (FESEM) and Energy Dispersive X-Ray (EDX). Following treatment with PTX-loaded NaCNs, cell viability, cellular uptake and morphological changes were analyzed using MCF-7 and MDA-MB 231 human breast cancer cell lines.

RESULTS

We found that PTX-loaded NaCNs efficiently released PTX in an acidic tumor environment, while showing an enhanced cytotoxicity, cellular uptake and in-vivo anti-tumor efficacy in a mouse model of breast cancer when compared to free drug and blank micelles. Additionally, the nanomicelles also presented improved colloidal stability for three months at 4 °C and -20 °C and when placed at a temperature of 37 °C.

CONCLUSIONS

We conclude that the newly developed NaCNs is a promising carrier of PTX to enhance tumor accumulation of the drug while addressing its toxicity issues as well.

Formulation and In Vitro Evaluation of Casein Nanoparticles as Carrier for Celecoxib

Purpose: The objective of this work was to formulate casein (CAS) nanocarriers for the dissolution enhancement of poorly water soluble drug celecoxib (CLXB).

Methods: The CLXB loaded CAS nanocarriers viz., nanoparticles, reassembled CAS micelles and nanocapsules were prepared using sodium caseinate (SOD-CAS) as a carrier to enhance the solubility of CLXB. The prepared formulations were characterized for particle size, polydispersity index, zeta potential, percentage entrapment efficiency, and surface morphology for the selection of best formulation. Fourier transform infrared spectroscopy, differential scanning calorimetry and X-ray powder diffraction study was used to for the confirmation of encapsulation of CLXB. Further,in vitro drug dissolution, ex-vivo permeation studies on chicken ileum and stability studies were carried out.

Results: The CLXB loaded casein nanoparticles (CNP) (batch A2) showed a particle size diameter 216.1 nm, polydispersity index 0.422 with percentage entrapment efficiency of 90.71% and zeta potential of -24.6 mV. Scanning electron microscopy of suspension confirmed globular shape of CNP. Thein vitro release data of optimized batch followed non Fickian diffusion mechanism. The ex vivo permeation studies on chicken ileum of CLXB loaded CNP showed permeation through mucous membrane as compared to pure CLXB. The apparent permeability of best selected freeze dried CLXB loaded CNP (batch A2) was higher and gradually increased from 0.90 mg/cm² after 10 min to a maximum of 1.95 mg/cm² over the subsequent 90 min. A higher permeation was recorded at each time point than that of the pure CLXB.

Conclusion: The study explored the potential of CAS as a carrier for solubility enhancement of poorly water soluble drugs.

Emergence in protein derived nanomedicine as anticancer therapeutics: More than a tour de force

Cancer has thwarted as a major health problem affecting the global population. With an alarming increase in the patient population suffering from diverse varieties of cancers, the global demographic data predicts sharp escalation in the number of cancer patients. This can be expected to reach 420 million cases by 2025. Among the diverse types of cancers, the most frequently diagnosed cancers are the breast, colorectal, prostate and lung cancer. From years, conventional treatment approaches like surgery, chemotherapy and radiation therapy have been practiced. In the past few years, increasing research on molecular level diagnosis and treatment of cancers have significantly changed the realm of cancer treatment. Lately, uses of advanced chemotherapy and immunotherapy like treatments have gained significant progress in the cancer therapy, but these approaches have several limitations on their safety and toxicity. This has generated lot of momentum for the evolution of new drug delivery approaches for the effective delivery of anticancer therapeutics, which may improve the pharmacokinetic and pharmacodynamic effect of the drugs along with significant reduction in the side effects. In this regard, the protein-based nano-medicines have gained wider attention in the management of cancer. Proteins are organic macromolecules essential, for life and have quite well explored in developing the nano-carriers. Furthermore, it provides passive or active tumour cell targeted delivery, by using protein based nanovesicles or virus like structures, antibody drug conjugates, viral particles, etc. Moreover, by utilizing various formulation strategies, both the animal and plant derived proteins can be converted to produce self-assembled virus like nano-metric structures with high efficiency in targeting the metastatic cancer cells. Therefore, the present review extensively discusses the applications of protein-based nano-medicine with special emphasis on intracellular delivery/drug targeting ability for anticancer drugs.

Recent trends in protein and peptide-based biomaterials for advanced drug delivery

Engineering protein and peptide-based materials for drug delivery applications has gained momentum due to their biochemical and biophysical properties over synthetic materials, including biocompatibility, ease of synthesis and purification, tunability, scalability, and lack of toxicity. These biomolecules have been used to develop a host of drug delivery platforms, such as peptide- and protein-drug conjugates, injectable particles, and drug depots to deliver small molecule drugs, therapeutic proteins, and nucleic acids. In this review, we discuss progress in engineering the architecture and biological functions of peptide-based biomaterials -naturally derived, chemically synthesized and recombinant- with a focus on the molecular features that modulate their structure-function relationships for drug delivery.

Magnetic Nanoclusters Coated with Albumin, Casein, and Gelatin: Size Tuning, Relaxivity, Stability, Protein Corona, and Application in Nuclear Magnetic Resonance Immunoassay

The surface functionalization of magnetic nanoparticles improves their physicochemical properties and applicability in biomedicine. Natural polymers, including proteins, are prospective coatings capable of increasing the stability, biocompatibility, and transverse relaxivity (r2) of magnetic nanoparticles. In this work, we functionalized the nanoclusters of carbon-coated iron nanoparticles with four proteins: bovine serum albumin, casein, and gelatins A and B, and we conducted a comprehensive comparative study of their properties essential to applications in biosensing. First, we examined the influence of environmental parameters on the size of prepared nanoclusters and synthesized protein-coated nanoclusters with a tunable size. Second, we showed that protein coating does not significantly influence the r2 relaxivity of clustered nanoparticles; however, the uniform distribution of individual nanoparticles inside the protein coating facilitates increased relaxivity. Third, we demonstrated the applicability of the obtained nanoclusters in biosensing by the development of a nuclear-magnetic-resonance-based immunoassay for the quantification of antibodies against tetanus toxoid. Fourth, the protein coronas of nanoclusters were studied using SDS-PAGE and Bradford protein assay. Finally, we compared the colloidal stability at various pH values and ionic strengths and in relevant complex media (i.e., blood serum, plasma, milk, juice, beer, and red wine), as well as the heat stability, resistance to proteolytic digestion, and shelf-life of protein-coated nanoclusters.

Emulsion and miniemulsion techniques in preparation of polymer nanoparticles with versatile characteristics

In recent years, polymer nanoparticles (PNPs) have found their ways into numerous applications extending from electronics to photonics, conducting materials to sensors and medicine to biotechnology. Physical properties and surface morphology of PNPs are the most important parameters that significantly affect on their exploitations and can be controlled through the synthesis process. Emulsion and miniemulsion techniques are among the most efficient and wide-spread methods for preparation of PNPs. The objective of this review is to present and highlight the recent developments in the advanced PNPs with specific properties that are produced through emulsion and miniemulsion processes.

Using a Microfluidics System to Reproducibly Synthesize Protein Nanoparticles: Factors Contributing to Size, Homogeneity, and Stability

The synthesis of Zein nanoparticles (NPs) using conventional methods, such as emulsion solvent diffusion and emulsion solvent evaporation, is often unreliable in replicating particle size and polydispersity between batch-to-batch syntheses. We have systematically examined the parameters for reproducibly synthesizing Zein NPs using a Y-junction microfluidics chip with staggered herringbone micromixers. Our results indicate that the total flow rate of the fluidics system, relative flow rate of the aqueous and organic phase, concentration of the base material and solvent, and properties of the solvent influence the polydispersity and size of the NPs. Trends such as increasing the total flow rate and relative flow rate lead to a decrease in Zein NP size, while increasing the ethanol and Zein concentration lead to an increase in Zein NP size. The solvent property that was found to impact the size of the Zein NPs formed the most was their hydropathy. Solvents that had a hydropathy index most similar to that of Zein formed the smallest Zein NPs. Synthesis consistency was confirmed within and between sample batches. Stabilizing agents, such as sodium caseinate, Tween 80, and Pluronic F-68, were incorporated using the microfluidics system, necessary for in vitro and in vivo use, into Zein-based NPs.

Protein/ Hormone Based Nanoparticles as Carriers for Drugs Targeting Protein-Protein Interactions

BACKGROUND

In this review, protein-protein interactions (PPIs) were defined, and their behaviors in normal in disease conditions are discussed. Their status at nuclear, molecular and cellular level was underscored, as for their interference in many diseases. Finally, the use of protein nanoscale structures as possible carriers for drugs targeting PPIs was highlighted.

OBJECTIVE

The objective of this review is to suggest a novel approach for targeting PPIs. By using protein nanospheres and nanocapsules, a promising field of study can be emerged.

METHODS

To solidify this argument, PPIs and their biological significance was discussed, same as their role in hormone signaling.

RESULTS

We shed the light on the drugs that targets PPI and we suggested the use of nanovectors to encapsulate these drugs to possibly achieve better results.

CONCLUSION

Protein based nanoparticles, due to their advantages, can be suitable carriers for drugs targeting PPIs. This can open a new opportunity in the emerging field of multifunctional therapeutics.

Elaboration of polymersomes versus conventional liposomes for improving oral bioavailability of the anticancer flutamide

Aim: Flutamide is an outstanding anticancer drug with poor oral bioavailability. This is the first work to investigate the potential of polymersomes versus conventional liposomes to improve flutamide bioavailability. Materials & methods: Polymersomes were prepared by solvent-switching technique and successfully optimized with excellent nanometric size (143 nm) and ζ-potential (-33.4 mV). Physicochemical characterization, stability in gastrointestinal tract and in vivo oral pharmacokinetics in male Sprague–Dawely rats were performed. Results: A significantly higher stability in simulated intestinal fluid was demonstrated by polymersomes compared with liposomes. Great improvement in flutamide oral bioavailability in polymersomes compared with both liposomes and drug suspension was obtained. Conclusion: Polymersomes are promising nanoplatforms to overcome stability problems of liposomes and to improve flutamide oral bioavailability.

Dual-targeted casein micelles as green nanomedicine for synergistic phytotherapy of hepatocellular carcinoma

In recent years, green nanomedicines have made transformative difference in cancer therapy researches. Herein, we propose dual-functionalized spray-dried casein micelles (CAS-MCs) for combined delivery of two phytochemicals; berberine (BRB) and diosmin (DSN) as targeted therapy of hepatocellular carcinoma (HCC). The nanomicelles enabled parenteral delivery of the poorly soluble DSN via its encapsulation within their hydrophobic core. Moreover, sustained release of the water soluble BRB was attained by hydrophobic ion pairing with sodium deoxycholate followed by genipin crosslinking of CAS-MCs. Dual-active targeting of MCs, via conjugating both lactobionic acid (LA) and folic acid (FA), resulted in superior cytotoxicity and higher cellular uptake against HepG2 cells compared to single-targeted and non-targeted CAS-MCs. The dual-targeted DSN/BRB-loaded CAS-MCs demonstrated superior in vivo anti-tumor efficacy in HCC bearing mice as revealed by down regulation of cell necrosis markers (NF-κB and TNF-α), inflammatory marker COX2, inhibition of angiogenesis and induction of apoptosis. Histopathological analysis and immunohistochemical Ki67 staining confirmed the superiority of the dual-targeted micelles. Ex-vivo imaging showed preferential liver-specific accumulation of dual-targeted CAS-MCs. Overall, this approach combined the benefits of traditional herbal medicine with nanotechnology via LA/FA-CAS-MCs loaded with BRB and DSN as a promising nanoplatform for targeted HCC therapy.

Alginate-caseinate composites: Molecular interactions and characterization of cross-linked beads for the delivery of anticandidals

Polysaccharide-protein composites offer potential utility for the delivery of drugs. The objectives of this work were to investigate the molecular interactions between sodium alginate (SA) and sodium caseinate (SC) in dispersions and films and to characterize calcium alginate (CA) beads mixed with SC for the delivery of fluconazole (FZ) and clotrimazole (CZ). The results demonstrated that SA could interact with SC, which caused a viscosity synergism in the dispersions. Hydrogen bonding between the carboxyl or hydroxyl groups of SA and the amide groups of SC led to the formation of soluble complexes that could reinforce the CA beads prepared by calcium cross-linking. The SC-CA beads provided higher drug entrapment efficiency, lower water uptake and erosion, and slower drug release than for the CA beads. The loaded FZ was an amorphous form, but CZ crystals were embedded in the bead matrix due to the low water solubility of this drug. However, SC micellization could enhance the water solubility and efficacy of CZ against Candida albicans. This finding indicates that SA can interact with SC via hydrogen bonding to form complexes and that the anticandidal-loaded SC-CA beads can be used as drug delivery systems and drug reservoirs in tablets for oral candidiasis.

Crosslinked casein-based micelles as a dually responsive drug delivery system

Crosslinked casein micelles with a dual pH and protease drug triggered release can be applied as a promising hydrophobic drug carrier material.

Smart Carriers and Nanohealers: A Nanomedical Insight on Natural Polymers

Biodegradable polymers are popularly being used in an increasing number of fields in the past few decades. The popularity and favorability of these materials are due to their remarkable properties, enabling a wide range of applications and market requirements to be met. Polymer biodegradable systems are a promising arena of research for targeted and site-specific controlled drug delivery, for developing artificial limbs, 3D porous scaffolds for cellular regeneration or tissue engineering and biosensing applications. Several natural polymers have been identified, blended, functionalized and applied for designing nanoscaffolds and drug carriers as a prerequisite for enumerable bionano technological applications. Apart from these, natural polymers have been well studied and are widely used in material science and industrial fields. The present review explains the prominent features of commonly used natural polymers (polysaccharides and proteins) in various nanomedical applications and reveals the current status of the polymer research in bionanotechnology and science sectors.

Protein-lipid nanohybrids as emerging platforms for drug and gene delivery: Challenges and outcomes

Nanoparticulate drug delivery systems have been long used to deliver a vast range of drugs and bioactives owing to their ability to demonstrate novel physical, chemical, and/or biological properties. An exponential growth has spurred in research and development of these nanocarriers which led to the evolution of a great number of diverse nanosystems including liposomes, nanoemulsions, solid lipid nanoparticles (SLNs), micelles, dendrimers, polymeric nanoparticles (NPs), metallic NPs, and carbon nanotubes. Among them, lipid-based nanocarriers have made the largest progress whether commercially or under development. Despite this progress, these lipid-based nanocarriers suffer from several limitations that led to the development of many protein-coated lipid nanocarriers. To less extent, protein-based nanocarriers suffer from limitations that led to the fabrication of some lipid bilayer enveloping protein nanocarriers. This review discusses in-depth some limitations associated with the lipid-based or protein-based nanocarriers and the fruitful outcomes brought by protein-lipid hybridization. Also discussed are the various hybridization techniques utilized to formulate these protein-lipid nanohybrids and the mechanisms involved in the drug loading process.

Protein-based nanoparticles: From preparation to encapsulation of active molecules

Nowadays, nanotechnology has become very integrated in the domain of pharmaceutical sciences since nanoparticle dispersions show various advantages as drug carriers. Among nanoparticles, the protein-based ones are of paramount importance. In fact, protein nanoparticles show many advantages over other types of nanoparticles, they are often non-toxic and biodegradable. In this review, the most common preparation methods of protein nanoparticles were targeted. In addition, the factors affecting their dispersions and the concepts of drug loading and drug release are also highlighted. It was obvious that each method can be optimized for a given protein. This issue was discussed in depth in the light of the current state of art, and supported by evidences for each method from the literature. In addition, it was concluded that the processing parameters strongly affect the properties of nanoparticles dispersion.

The role of surface charge in the desolvation process of gelatin: implications in nanoparticle synthesis and modulation of drug release

The process of moving hydrophobic amino acids into the core of a protein by desolvation is important in protein folding. However, a rapid and forced desolvation can lead to precipitation of proteins. Desolvation of proteins under controlled conditions generates nanoparticles – homogeneous aggregates with a narrow size distribution. The protein nanoparticles, under physiological conditions, undergo surface erosion due to the action of proteases, releasing the entrapped drug/gene. The packing density of protein nanoparticles significantly influences the release kinetics. We have investigated the desolvation process of gelatin, exploring the role of pH and desolvating agent in nanoparticle synthesis. Our results show that the desolvation process, initiated by the addition of acetone, follows distinct pathways for gelatin incubated at different pH values and results in the generation of nanoparticles with varying matrix densities. The nanoparticles synthesized with varying matrix densities show variations in drug loading and protease-dependent extra- and intracellular drug release. These results will be useful in fine-tuning the synthesis of nanoparticles with desirable drug release profiles.

Overcoming T. gondii infection and intracellular protein nanocapsules as biomaterials for ultrasonically controlled drug release

One of the pivotal matters of concern in intracellular drug delivery is the preparation of biomaterials containing drugs that are compatible with the host target.

In silico-in vitro-in vivo studies of experimentally designed carvedilol loaded silk fibroin-casein nanoparticles using physiological based pharmacokinetic model

The study aimed to design and develop carvedilol loaded silk fibroin-casein nanoparticles using 3² full factorial design. Silk fibroin and casein concentration were selected as the independent variables and their effect were observed on dependent variables: particle size, polydispersity index, encapsulation efficiency, drug release, and dissolution efficiency. The developed optimized formulation was characterized using fourier transform infrared spectroscopy, differential scanning calorimetry, and Powder X-ray diffraction. Surface morphology of optimized formulation using scanning electron microscopy, transmission electron microscopy, and atomic force microscopy revealed spherical nature of particles without any evidence of aggregation. The optimized formulation showed a 2.04-fold increase in C_max, and 6.87-fold increase in bioavailability as compared to aqueous suspension. The formulation showed sustained release as confirmed by increases in mean residence time. The in vivo in silico simulation using physiologically based pharmacokinetics (PBPK) model and population simulation (100 subjects) revealed a reasonable degree of superimposition of simulated and observed pharmacokinetic parameters based on overall fold error (≤2.0). The enhanced bioavailability with sustained effect demonstrates potential of silk fibroin as an alternative carrier for drug delivery and presents Gastoplus™ as efficient tool for in vivo in silico simulations.

Preparation of Fucoxanthin-Loaded Nanoparticles Composed of Casein and Chitosan with Improved Fucoxanthin Bioavailability

To facilitate the utilization of fucoxanthin (FX), a valuable marine carotenoid, in the food industry, FX-loaded casein nanoparticles (FX-CN) and chitosan-coated FX-CN (FX-CS-CN) were developed using the FX-enriched fraction from Phaeodactylum tricornutum. Two nanoscale particles (237 ± 13 nm for FX-CN and 277 ± 26 nm for FX-CN-CN) with spherical and smooth surfaces showed over 71% encapsulation efficiency and polydispersity index (PDI) value of 0.31-0.39 in water. Owing to the chitosan coating, FX-CS-CN showed a positive zeta potential (24.00 mV), whereas that of FX-CN was negative (-12.87 mV). In vitro simulated digestion demonstrated better FX bioaccessibility from the nanoparticles versus P. tricornutum powder (Pt-powder) and from FX-CN versus FX-CS-CN. However, in C57BL/6 mice, fucoxanthinol absorption to the blood circulation was two times higher for FX-CS-CN versus FX-CN, possibly due to increased retention or adsorption to mucin by the cationic biopolymer in the chitosan-coated particles. These results demonstrate that FX-CS-CN can enable the application of FX, with improved bioavailability and water dispersibility, in the food industry.

HPLC Methods for Quantitation of Exemestane-Luteolin and Exemestane-Resveratrol Mixtures in Nanoformulations

Two HPLC-DAD assays for the simultaneous quantitation of exemestane (EXE) and resveratrol (RES)-Mix 1-and EXE and luteolin (LUT)-Mix 2-in novel breast cancer therapy nanoformulations were developed. Calibration curves 15-30 µg/mL and samples were injected through an Inertsil ODS-3 (250 × 4.6 mm, 5 µm) column. The gradient elution for Mix 1 was methanol : 0.05% (v/v) acetic acid in water (60 : 40 to 80 : 20, linear over 2 min), and for Mix 2, it was methanol : water (60 : 40 for 4 min, then ramped linearly to 90 : 10, over 12 min) pumped at 1.5 mL/min for 4 min, then 1 mL/min till the end of run. EXE, RES, LUT and flutamide (internal standard (IS)) were measured at 246, 307, 350 and 300 nm, respectively. For Mix 1, RES, EXE and IS eluted at 3.5, 6.8 and 7.4 min, respectively, while for Mix 2, LUT, EXE and IS eluted at 7.5, 11.4 and 12.7 min, respectively. The mean r(2) for the standard curves was ≥0.99, and percentage coefficient of variation and % error of the mean were <2. Both assays successfully quantitated Mix 1 and Mix 2 in their nanoformulations. The two developed assays were sensitive and selective for the analysis of EXE-LUT and EXE-RES mixtures in nanoformulations according to International Conference on Harmonization guidelines.

A sight on protein-based nanoparticles as drug/gene delivery systems

Polymeric nanomaterials have extensively been applied for the preparation of targeted and controlled release drug/gene delivery systems. However, problems involved in the formulation of synthetic polymers such as using of the toxic solvents and surfactants have limited their desirable applications. In this regard, natural biomolecules including proteins and polysaccharide are suitable alternatives due to their safety. According to literature, protein-based nanoparticles possess many advantages for drug and gene delivery such as biocompatibility, biodegradability and ability to functionalize with targeting ligands. This review provides a general sight on the application of biodegradable protein-based nanoparticles in drug/gene delivery based on their origins. Their unique physicochemical properties that help them to be formulated as pharmaceutical carriers are also discussed.