Engineered multifunctional biodegradable hybrid microparticles for paclitaxel delivery in cancer therapy

Biodegradable microspheres come into sight: A promising biomaterial for delivering drug to the posterior segment of the eyeball

Posterior segment disease acts as a major cause of irreversible visual impairments. Successful treatment of posterior segment disease requires the efficient delivery of therapeutic substances to the targeted lesion. However, the complex ocular architecture makes the bioavailability of topically applied drugs extremely low. Invasive delivery approaches like intravitreal injection may cause adverse complications. To enhance the efficiency, several biomedical engineering systems have been developed to increase the penetration efficiency and improve the bioavailability of drugs at the posterior segments. Advantageously, biodegradable microspheres are found to deliver the therapeutic agents in a controlled fashion. The microspheres prepared from novel biomaterials can realize the prolonged release at the posterior segment with minimum side effects. Moreover, it will be degraded automatically into products that are non-toxic to the human body without the necessity of secondary operation to remove the residual polymer matrix. Additionally, biodegradable microspheres have decent thermoplasticity, adjustable hydrophilicity, controlled crystallinity, and high tensile strength, which make them suitable for intraocular delivery. In this review, we introduce the latest advancements in microsphere production technology and elaborate on the biomaterials that are used to prepare microspheres. We discuss systematically the pharmacological characteristics of biodegradable microspheres and compare their potential advantages and limitations in the treatment of posterior segment diseases. These findings would enrich our knowledge of biodegradable microspheres and cast light into the discovery of effective biomaterials for ocular drug delivery.

Rosmarinic acid Ameliorates neuronal regeneration in the bridging silicone rubber conduits of the sciatic nerve in taxol-treated rats

Background and aim

Taxol modulates local inflammatory conditions in peripheral nerves, which may impair their regeneration and recovery when injured. This study aimed to determine the effects of rosmarinic acid (RA, a polyphenol constituent of many culinary herbs) on the regeneration of the sciatic nerves in the bridging conduits.

Experimental procedure

In the cell study, RA decreased nuclear factor (NF)-κB activity induced by taxol in a dose dependency. In the animal model, taxol-treated rats were divided into 3 groups (n = 10/group): taxol (2 mg/kg body weight for 4 times) and taxol + RA (3 times/week for 4 weeks at 20 and 40 mg/kg body weight) groups. Macrophage infiltration, calcitonin gene-related peptide (CGRP) expression levels, neuronal connectivity, animal behavior, and neuronal electrophysiology were evaluated.

Results and conclusion

At the end of 4 weeks, macrophage density, CGRP expression level, and axon number significantly increased in the RA group compared with the taxol group. The RA administration unaffected heat, cold plate licking latencies, and motor coordination. Moreover, the 40 mg/kg RA group had significantly larger nerve conduction velocity and less latency compared to the taxol group. This study suggested that RA could ameliorate local inflammatory conditions to augment the recovery of regenerating nerves by accelerating their regrowth and improving electrophysiological function in taxol-treated peripheral nerve injury repaired with the silicone rubber conduit.

Drug-loaded erythrocytes: Modern approaches for advanced drug delivery for clinical use

Scientific organizations worldwide are striving to create drug delivery systems that provide a high local concentration of a drug in pathological tissue without side effects on healthy organs in the body. Important physiological properties of red blood cells (RBCs), such as frequent renewal ability, good oxygen carrying ability, unique shape and membrane flexibility, allow them to be used as natural carriers of drugs in the body. Erythrocyte carriers derived from autologous blood are even more promising drug delivery systems due to their immunogenic compatibility, safety, natural uniqueness, simple preparation, biodegradability and convenience of use in clinical practice. This review is focused on the achievements in the clinical application of targeted drug delivery systems based on osmotic methods of loading RBCs, with an emphasis on advancements in their industrial production. This article describes the basic methods used for encapsulating drugs into erythrocytes, key strategic approaches to the clinical use of drug-loaded erythrocytes obtained by hypotonic hemolysis. Moreover, clinical trials of erythrocyte carriers for the targeted delivery are discussed. This article explores the recent advancements and engineering approaches employed in the encapsulation of erythrocytes through hypotonic hemolysis methods, as well as the most promising inventions in this field. There is currently a shortage of reviews focused on the automation of drug loading into RBCs; therefore, our work fills this gap. Finally, further prospects for the development of engineering and technological solutions for the automatic production of drug-loaded RBCs were studied. Automated devices have the potential to provide the widespread production of RBC-encapsulated therapeutic drugs and optimize the process of targeted drug delivery in the body. Furthermore, they can expedite the widespread introduction of this innovative treatment method into clinical practice, thereby significantly expanding the effectiveness of treatment in both surgery and all areas of medicine.

Fabrication of biodegradable hollow microsphere composites made of polybutylene adipate co-terephthalate/polyvinylpyrrolidone for drug delivery and sustained release

Sustained drug release has attracted increasing interest in targeted drug therapy. However, existing methods of drug therapy suffer drug action time, large fluctuations in the effective concentration of the drug, and the risk of side effects. Here, a biodegradable composite of polybutylene adipate co-terephthalate/polyvinylpyrrolidone (PBAT/PVP) consisting of electrospun hollow microspheres as sustained-released drug carriers is presented. The as-prepared PBAT/PVP composites show faster degradation rate and drug (Erlotinib) release than that of PBAT. Furthermore, PBAT/PVP composites loaded with Erlotinib provide sustained release effect, thus achieving a better efficacy than that after the direct injection of erlotinib due to the fact that the composites allow a high drug concentration in the tumor for a longer period. Hence, this work provides a potential effective solution for clinical drug therapy and tissue engineering using drug microspheres with a sustained release.

Microparticles in the Development and Improvement of Pharmaceutical Formulations: An Analysis of In Vitro and In Vivo Studies

Microparticulate systems such as microparticles, microspheres, microcapsules or any particle in a micrometer scale (usually of 1–1000 µm) are widely used as drug delivery systems, because they offer higher therapeutic and diagnostic performance compared to conventional drug delivery forms. These systems can be manufactured with many raw materials, especially polymers, most of which have been effective in improving the physicochemical properties and biological activities of active compounds. This review will focus on the in vivo and in vitro application in the last decade (2012 to 2022) of different active pharmaceutical ingredients microencapsulated in polymeric or lipid matrices, the main formulation factors (excipients and techniques) and mostly their biological activities, with the aim of introducing and discussing the potential applicability of microparticulate systems in the pharmaceutical field.

Biocompatibility and Antibacterial Effect of Ginger Fraction Loaded PLGA Microspheres Fabricated by Coaxial Electrospray

Various poly(lactic-co-glycolic acid) (PLGA) microspheres loaded with the ginger fraction were fabricated by controlling the electrospray parameters and their biocompatibility and antibacterial activity were identified in this study. The morphology of the microspheres was observed using scanning electron microscopy. The core-shell structures of the microparticles and the presence of ginger fraction in the microspheres were confirmed by fluorescence analysis using a confocal laser scanning microscopy system. In addition, the biocompatibility and antibacterial activity of PLGA microspheres loaded with ginger fraction were evaluated through a cytotoxicity test using osteoblast MC3T3-E1 cells and an antibacterial test using Streptococcus mutans and Streptococcus sanguinis, respectively. The optimum PLGA microspheres loaded with ginger fraction were fabricated under electrospray operational conditions with 3% PLGA concentration in solution, an applied voltage of 15.5 kV, a flow rate of 15 µL/min in the shell nozzle, and 3 µL/min in the core nozzle. The effectual antibacterial effect and enhanced biocompatibility were identified when a 3% ginger fraction in PLGA microspheres was loaded.

Solvent-Free Fabrication of Biphasic Lipid-Based Microparticles with Tunable Structure

Lipid-based biphasic microparticles are generally produced by long and complex techniques based on double emulsions. In this study, spray congealing was used as a solvent-free fabrication method with improved processability to transform water-in-oil non-aqueous emulsions into spherical solid lipid-based particles with a biphasic structure (b-MPs). Emulsions were prepared by melt emulsification using different compositions of lipids (Dynasan^®118 and Compritol^®888 ATO), surfactants (Cetylstearyl alcohol and Span^®60) and hydrophilic carriers (PEGs, Gelucire^®48/16 and Poloxamer 188). First, pseudo-ternary phase diagrams were constructed to identify the area corresponding to each emulsion type (coarse emulsion or microemulsion). The hydrophobicity of the lipid mostly affected the interfacial tension, and thus the microstructure of the emulsion. Emulsions were then processed by spray congealing and the obtained b-MPs were characterized in terms of thermal and chemical properties (by DSC and FT-IR), external and internal morphology (by SEM, CLSM and Raman mapping). Solid free-flowing spherical particles (main size range 200–355 µm) with different architectures were successfully produced: microemulsions led to the formation of particles with a homogeneous internal structure, while coarse emulsions generated “multicores-shell” particles consisting of variable size hydrophilic cores evenly distributed within the crystalline lipid phase. Depending on their composition and structure, b-MPs could achieve various release profiles, representing a more versatile system than microparticles based on a single lipid phase. The formulation and technological strategy proposed, provides a feasible and cost-effective way of fabricating b-MPs with tunable internal structure and release behavior.

PLGA Core-Shell Nano/Microparticle Delivery System for Biomedical Application

Core-shell particles are very well known for their unique features. Their distinctive inner core and outer shell structure allowed promising biomedical applications at both nanometer and micrometer scales. The primary role of core-shell particles is to deliver the loaded drugs as they are capable of sequence-controlled release and provide protection of drugs. Among other biomedical polymers, poly (lactic-co-glycolic acid) (PLGA), a food and drug administration (FDA)-approved polymer, has been recognized for the vehicle material. This review introduces PLGA core-shell nano/microparticles and summarizes various drug-delivery systems based on these particles for cancer therapy and tissue regeneration. Tissue regeneration mainly includes bone, cartilage, and periodontal regeneration.

Folate-conjugated hydrophobicity modified glycol chitosan nanoparticles for targeted delivery of methotrexate in rheumatoid arthritis

BACKGROUND

Targeted delivery to the Rheumatoid arthritis (RA) which is characterized by destruction and degeneration of bones due to chronic inflammation is of great need. RA being a chronic autoimmune disorder might result in severe disability and morbidity. A targeted delivery system is designed to deliver methotrexate (MTX) for RA.

METHODS

Here, we synthesized folic acid (FA) conjugated hydrophobically modified glycol chitosan (GC) self-assembled nanoparticles (FA-GC-SA) for the targeted delivery of MTX to RA. The FA conjugation and hydrophobic modification of GC by stearic acid (SA) was confirmed by Fourier-transform infrared spectroscopy (FTIR). The FA-GC-SA was exploited for developing targeted nanoparticles encapsulating MTX by the ionic gelation method. The particles were characterized and evaluated for their targeting potential in in vitro cell culture studies. Further their in vivo efficacy in arthritis induced rats using collagen was also evaluated.

RESULTS

FTIR confirms the successful modification of GC-SA and FA-GC-SA. The FA-GC-SA-MTX of size 153 ± 9 nm were prepared with high encapsulation efficiency of MTX. The FA-GC-SA-MTX size was further confirmed by transmission electron microscopy (TEM). In vitro cell studies revealed the superior efficacy of FA-GC-SA-MTX in cell cytotoxicity. Also, significantly higher cellular uptake of FA functionalized FA-GC-SA-MTX was observed in comparison to non-functionalized GC-SA-MTX attributed to folate receptors (FRs) mediated endocytosis. In vivo results confirms the potential of FA-GC-SA-MTX which reduces reduces the pro-inflammatory cytokines, paw thickness, and arthritis score in collagen induced rats.

CONCLUSION

The results shows that FRs targeted FA-GC-SA-MTX has superior efficacy in the treatment of RA.

Anti-inflammatory cytokine IL10 loaded cRGD liposomes for the targeted treatment of atherosclerosis

AIM

Atherosclerosis (AS) is one of the main causes of cardiovascular disease which might lead to myocardial infarction or stroke and further leads to fatality.

METHOD

In this study, we have designed an anti-inflammatory cytokine interleukin-10 (IL10) delivery system to effectively alleviate the inflammation of atherosclerosis plaque. The targeted delivery of IL10 to the atherosclerotic plaques was achieved by cRGD conjugated liposomes (IL10-cRGD-Lip).

RESULTS

The IL10-cRGD-Lip of size 179.4 ± 10.91 nm having PDI 0.14 ± 0.04 with a surface charge of +18.34 ± 1.36 mV was prepared. The in-vitro analysis clearly suggests that IL10-cRGD-Lip sustains the release of IL10 and could significantly reduce ROS and NO. The immuno-staining results revealed that IL-1β and TNF-α were down-regulated after the treatment with IL10-cRGD-Lip in Lipopolysaccharide (LPS) stimulated RAW 264.7 cells.

CONCLUSION

the in-vitro results clearly suggest that anti-inflammatory cytokine IL10 could be used for the cure of inflammatory maladies including atherosclerosis.

Intranasal delivery of Paclitaxel encapsulated nanoparticles for brain injury due to Glioblastoma

Brain injury is a common cause for physical and emotional effects to the large number of populations. Moreover, glioblastoma is the tumor in brain with no possible treatment leading to death. The blood-brain barrier's makes the treatment more difficult by preventing the drugs to reach central nervous system. Paclitaxel (PTX) encapsulated Poly (lactic-co-glycolic acid) (PLGA) nanoparticles (NPs), PTX-PLGA-NPs were developed using emulsification method. The PTX-PLGA-NPs were characterized using Malvern Zetasizer and Scanning Electron Microscopy and were evaluated for their cytotoxicity in U87MG cells. PTX-PLGA-NPs were prepared using single emulsion method having size of 154 ± 22.19 nm with zeta potential of -23.7 mV. The PTX-PLGA-NPs were spherical in shape and have dose dependent cytotoxicity on U87MG cells. The PTX was released from the particles with initial burst release followed by sustained release pattern. The biodistribution was studied in mice with glioblastoma model using ¹²⁵I radiolabeled PTX-PLGA-NPs and anti-glioblastoma was studied with PTX-PLGA-NPs. The biodistribution studies revealed PTX-PLGA-NPs after intranasal administration resulted in higher in vivo uptake with high anti-glioblastoma efficacy. The results suggest that PTX-PLGA-NPs administered through intranasal route have potential in the treatment of glioblastoma.

Brinzolamide loaded core-shell nanoparticles for enhanced coronial penetration in the treatment of glaucoma

A neurodegenerative disorder, glaucoma is a leading cause of blindness in the world. The conventional treatment strategies do not allow the significant penetration of the drug in the cornea. Therefore, we prepare a brinzolamide (Brz) loaded core-shell nanoparticles (NPs) to enhance the coronial penetration of the drug and thus treating the glaucoma. The shell of the NPs was composed of phosphatidylserine (PS; 1,2-diacyl-sn-glycero-3-phospho-L-serine), whereas the core of the NPs contains the Brz encapsulated in brinzolamide–phosphatidylserine–polymer poly-(DL-lactic acid-co-glycolic acid)–phosphatidylserine (Brz-PS-PLGA). The synthesis of Brz-PS-PLGA was achieved by using a coaxial electrospray process (CEP), which allows the preparation of the particles in a single step. The size of Brz-PS-PLGA with PS shell and brinzolamide–poly (lactic-co-glycolic) acid (Brz-PLGA) without shell was 571 ± 27.02 nm and 456 ± 19.17 nm, respectively. The charges on the surface of Brz-PS-PLGA and Brz-PLGA were (-) 27.45 ± 2.98 mV and (-) 19.47 ± 2.83 mV. The transmission electron microscopy images clearly reveal the PS shell as a light black layer over the dark black PLGA core. The CEP allows the high encapsulation of Brz in Brz-PS-PLGA where percentage of entrapment efficiency for Brz-PS-PLGA was 88.13 ± 6.43%. The release study conducted in a simulated tear fluid revealed the sustained release patterns of Brz from Brz-PS-PLGA and these were nontoxic to the cells as revealed by the cytotoxicity studies. Further, the Brz-PS-PLGA enhanced the coronial penetration of Brz and was capable of significantly reducing the intraocular pressure (IOP) after administration to the rabbit eye in comparison to the Brz-PLGA and free Brz. The results clearly suggest that the PS coating significantly enhances the capability of the particles in reducing IOP.

Structured micro/nano materials synthesized via electrospray: a review

The development of synthetic methods for micro/nano materials with precisely controlled structures, morphologies, and local compositions is of great importance for the advancement of modern nanotechnology. The electrospray method is a "platform" approach for the preparation of a broad range of micro-/nanostructures; electrospray is simple and scalable. This review summarizes recent research on the micro-/nanostructures prepared via the electrospray route. These include spherical structures (e.g. simple, porous, Janus, and core-shell particles), non-spherical structures (e.g. red blood cell-like and spindle-like particles, multi-compartment microrods, 2D holey nanosheets, and nanopyramids), and assembled structures. The experimental details, underlying physical/chemical principles, and key benefits of these structures are comprehensively discussed. The effects and importance of nozzle design, properties of feeding solutions (e.g. concentration of solute, polymer additives, solvent/nonsolvent combinations), working environment (e.g. temperature and humidity), and types of collection media are highlighted.

Selective separation and inexpensive purification of paclitaxel based on molecularly imprinted polymers modified with ternary deep eutectic solvents

Paclitaxel (PTX) is a powerful anticancer natural product, with its separation and purification having been widely studied. In this work, new molecular imprinted polymers (MIPs) using deep eutectic solvents (DESs) with different molar ratios were prepared as functional monomers. These were then used as adsorbents in solid phase extraction (SPE) for the separation of PTX from its structural analogs. The polymers were characterized by energy disperive X-rays (EDX), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and fourier transform infrared spectroscopy (FT-IR). The results suggested that the formative regular DES-MIPs had an even pore-size distribution and a large specific surface area. The dynamic adsorption and static adsorption showed that the DES-MIPs had excellent adsorption performance, with a maximum adsorption capacity and optimum adsorption time of 87.08 mg/g and 180 min, respectively. The selective adsorption experiments showed that the material had outstanding selectivity, and the maximum selectivity factor was 6.20. For stability, after six consecutive adsorption and desorption cycles, the DES-MIPs maintained the perfect stability and reusability. Furthermore, the fabricated SPE column was successfully utilized for extracting and eluting PTX. This study provides a reliable protocol for the separation and purification PTX from its structural analogs and the DES-MIPs materials have excellent potential application value in pharmaceutical industry.

Rhein laden pH-responsive polymeric nanoparticles for treatment of osteoarthritis

Osteoarthritis (OA) is a condition associated with severe inflammation, cartilage destruction and degeneration of joints. Rhein (Rh) is an effective anti-inflammatory drug with proven efficacy in in-vitro and in-vivo models. pH sensitive Rh and NH₄HCO₃ laden poly (lactic-co-glycolic acid (PLGA) nanoparticles (NPs) (Rh-PLGA-NPs@NH₄) are developed for an effective treatment of OA. The Rh-PLGA-NPs@NH₄ are prepared along with Rh-PLGA-NPs as a control by double emulsion method. Rh-PLGA-NPs@NH₄ was characterized for their size, shape, morphology and encapsulation efficiency (EE). The effect of pH on release of Rh from Rh-PLGA-NPs@NH₄ was studied at different pH. Further, the cytotoxicity effect of Rh-PLGA-NPs@NH₄ on THP-1 cells were evaluated. Anti-inflammatory efficacy was evaluated on LPS stimulated THP-1 cells and the release of pro-inflammatory cytokines was evaluated and compared with control. The size of Rh-PLGA-NPs@NH₄ and Rh-PLGA-NPs was found to be 190.7 ± 1.2 nm and 134.6 ± 2.4 nm respectively with poly dispersity (PDI) 0.14 and 0.15. The zeta potential of Rh-PLGA-NPs@NH₄ was found to be -22 ± 1.12 mV. Rh-PLGA-NPs@NH₄ were uniform, smooth and spherical shape as confirmed using electron microscopy analysis. Rh-PLGA-NPs@NH₄ release the Rh more effectively in the low pH of synovial fluid environment (SFE). Rh-PLGA-NPs@NH₄ also significantly affect inflammatory cytokines TNF-α and IL-1β and reduced their release in LPS stimulated THP-1 cells. Reactive oxygen species (ROS), a mediator responsible for the cartilage collapse was also found to be reduced. Results proposes that Rh-PLGA-NPs could provide therapeutic solution to those patients who suffer from chronic joint ailments by reducing the progression of OA.

Pristine Cu-MOF Induces Mitotic Catastrophe and Alterations of Gene Expression and Cytoskeleton in Ovarian Cancer Cells

Metals-organic frameworks (MOFs) have been widely explored in biomedicine, mostly in drug delivery, biosensing, and bioimaging due to their large surface area, tunable porosity, readily chemical functionalization, and good biocompatibility. However, the underlining cellular mechanisms controlling the process for MOF cytotoxicity remains almost completely unknown. Here, we demonstrate that pristine Cu-MOF without any loaded drug selectively inhibited ovarian cancer mainly through promoting tubulin polymerization and destroying the cell actin cytoskeleton (F-actin) to trigger the mitotic catastrophe, accompanying by conventional programmed cell death. To our knowledge, this is the first report claiming that mitotic catastrophe may be an explaining mechanism of MOF cytotoxicity. Cu-MOF with an intrinsic protease-like activity also hydrolyzed cellular cytoskeleton proteins (F-actin). The RNA sequencing data indicated the differential expressional mRNA of cell proliferation and actin cytoskeleton (ACTA2, ACTN3, FSCN2, and SCIN) and mitotic spindles (PLK1 and TPX2) related genes. We found that Cu-MOF as a promising candidate in the disruption of cellular cytoskeleton and the change of the gene expression could be actin altering and antimitotic agents against cancer cells, allowing for fundamental biological and biophysical studies of MOFs.

Integrin αvβ3 Receptor Overexpressing on Tumor-Targeted Positive MRI-Guided Chemotherapy

Multifunctional nanomaterials with targeted imaging and chemotherapy have high demand with great challenge. Herein, we rationally aimed to design multifunctional drug delivery systems by RGD-modified chitosan (CH)-coated nanoneedles (NDs) of gadolinium arsenate (RGD-CH-Gd-AsNDs). These NDs have multifunctionality for imaging and targeted therapy. NDs on intravenous administration demonstrated significant accumulation of As ions/species in tumor tissues, which was monitored by the change in T₁-weighted magnetic resonance (MR) imaging. Moreover, NDs were well opsonized in cells with high specificity, subsequently inducing apoptosis to the HepG2 cells. Consequent to this, the in vivo results demonstrated biosafety, enhanced tumor targeting, and tumor regression in a subcutaneously transplanted xenograft model in nude mice. These RGD-CH-Gd-AsNDs have great potential, and we anticipate that they could serve as a novel platform for real-time T₁-weighted MR diagnosis and chemotherapy.

Pharmacokinetic Profile and Anti-Adhesive Effect of Oxaliplatin-PLGA Microparticle-Loaded Hydrogels in Rats for Colorectal Cancer Treatment

Colorectal cancer (CRC) is one of the most malignant and fatal cancers worldwide. Although cytoreductive surgery combined with chemotherapy is considered a promising therapy, peritoneal adhesion causes further complications after surgery. In this study, oxaliplatin-loaded Poly-(d,l-lactide-co-glycolide) (PLGA) microparticles were prepared using a double emulsion method and loaded into hyaluronic acid (HA)- and carboxymethyl cellulose sodium (CMCNa)-based cross-linked (HC) hydrogels. From characterization and evaluation study PLGA microparticles showed smaller particle size with higher entrapment efficiency, approximately 1100.4 ± 257.7 nm and 77.9 ± 2.8%, respectively. In addition, microparticle-loaded hydrogels showed more sustained drug release compared to the unloaded microparticles. Moreover, in an in vivo pharmacokinetic study after intraperitoneal administration in rats, a significant improvement in the bioavailability and the mean residence time of the microparticle-loaded hydrogels was observed. In HC21 hydrogels, AUC0-48h, Cmax, and Tmax were 16012.12 ± 188.75 ng·h/mL, 528.75 ± 144.50 ng/mL, and 1.5 h, respectively. Furthermore, experimental observation revealed that the hydrogel samples effectively protected injured tissues from peritoneal adhesion. Therefore, the results of the current pharmacokinetic study together with our previous report of the in vivo anti-adhesion efficacy of HC hydrogels demonstrated that the PLGA microparticle-loaded hydrogels offer novel therapeutic strategy for CRC treatment.