Characteristics of Artemether-Loaded Poly(lactic-co-glycolic) Acid Microparticles Fabricated by Coaxial Electrospray: Validation of Enhanced Encapsulation Efficiency and Bioavailability

Injectable controlled-release systems for the prevention and treatment of infectious diseases

Pharmaceutical drugs, including vaccines, pre- and post-exposure prophylactics, and chronic drug therapies, are crucial tools in the prevention and treatment of infectious diseases. These drugs have the ability to increase survival and improve patient quality of life; however, infectious diseases still accounted for more than 10.2 million deaths in 2019 before the COVID-19 pandemic. High mortality can be, in part, attributed to challenges in the availability of adequate drugs and vaccines, limited accessibility, poor drug bioavailability, the high cost of some treatments, and low patient adherence. A majority of these factors are logistical rather than technical challenges, providing an opportunity for existing drugs and vaccines to be improved through formulation. Injectable controlled-release drug delivery systems are one class of formulations that have the potential to overcome many of these limitations by releasing their contents in a sustained manner to reduce the need for frequent re-administration and improve clinical outcomes. This review provides an overview of injectable controlled drug delivery platforms, including microparticles, nanoparticles, and injectable gels, detailing recent developments using these systems for single-injection vaccination, long-acting prophylaxis, and sustained-release treatments for infectious disease.

Recent advances of electrospray technique for multiparticulate preparation: Drug delivery applications

The electrospray (ES) technique has proven to be an effective and a versatile approach for crafting drug delivery carriers with diverse dimensions, multiple layers, and varying morphologies. Achieving the desired particle properties necessitates careful optimization of various experimental parameters. This review delves into the most prevalent ES system configurations employed for this purpose, such as monoaxial, coaxial, triaxial, and multi-needle setups with solid or liquid collector. In addition, this work underscores the significance of ES in drug delivery carriers and its remarkable ability to encapsulate a wide spectrum of therapeutic agents, including drugs, nucleic acids, proteins, genes and cells. Depth examination of the critical parameters governing the ES process, including the choice of polymer, surface tension, voltage settings, needle size, flow rate, collector types, and the collector distance was conducted with highlighting on their implications on particle characteristics, encompassing morphology, size distribution, and drug encapsulation efficiency. These insights illuminate ES's adaptability in customizing drug delivery systems. To conclude, this review discusses ES process optimization strategies, advantages, limitations and future directions, providing valuable guidance for researchers and practitioners navigating the dynamic landscape of modern drug delivery systems.

Free-Boundary Microfluidic Platform for Advanced Materials Manufacturing and Applications

Microfluidics, with its remarkable capacity to manipulate fluids and droplets at the microscale, has emerged as a powerful platform in numerous fields. In contrast to conventional closed microchannel microfluidic systems, free-boundary microfluidic manufacturing (FBMM) processes continuous precursor fluids into jets or droplets in a relatively spacious environment. FBMM is highly regarded for its superior flexibility, stability, economy, usability, and versatility in the manufacturing of advanced materials and architectures. In this review, a comprehensive overview of recent advancements in FBMM is provided, encompassing technical principles, advanced material manufacturing, and their applications. FBMM is categorized based on the foundational mechanisms, primarily comprising hydrodynamics, interface effects, acoustics, and electrohydrodynamic. The processes and mechanisms of fluid manipulation are thoroughly discussed. Additionally, the manufacturing of advanced materials in various dimensions ranging from zero-dimensional to three-dimensional, as well as their diverse applications in material science, biomedical engineering, and engineering are presented. Finally, current progress is summarized and future challenges are prospected. Overall, this review highlights the significant potential of FBMM as a powerful tool for advanced materials manufacturing and its wide-ranging applications.

Evaluation of Pharmacokinetics, Biodistribution, and Antimalarial Efficacy of Artemether-Loaded Polymeric Nanorods

Artemether oily injection is recommended for the treatment of severe malaria by the intramuscular route. The major limitations of the artemisinin combination therapy are erratic absorption from the injection site and high dosing frequency due to a very short elimination half-life of the drug. Advanced drug delivery systems have shown significant improvement in the current malaria therapy; the desired drug concentration within infected erythrocytes is yet the major challenge. Recently, we have reported the fabrication of artemether-loaded polymeric nanorods for intravenous malaria therapy which was found to be biocompatible with THP-1 monocytes and rat erythrocytes. The objective of the present study was the evaluation of pharmacokinetics, biodistribution, and antimalarial efficacy of artemether-loaded polymeric nanorods. Scanning electron microscopy and confocal microscopy studies revealed that both nanospheres and nanorods were adsorbed onto the surface of rat erythrocytes after an incubation of 10 min. After intravenous administration to rats, artemether nanorods showed higher plasma concentration and lower elimination rate of artemether when compared with nanospheres. The biodistribution studies showed that, at 30 min, the liver concentration of DiR-loaded nanospheres was higher than that of DiR-loaded nanorods after intravenous administration to BALB/c mice. The in vitro schizont inhibition study showed that both nanorods and nanospheres exhibited concentration-dependent parasitic inhibition, wherein at lower concentrations (2 ppm), nanorods were more effective than nanospheres. However, at higher concentrations, nanospheres were found to be more effective. Nanorods showed higher chemosuppression on day 5 and day 7 than nanospheres and free artemether when studied with the Plasmodium berghei mouse model. Moreover, the survival rate of P. berghei infected mice was also found to be higher after treatment with artemether nanoformulations when compared with free artemether. In conclusion, polymeric nanorods could be a promising next-generation delivery system for the treatment of malaria.

Oral colon-targeting core-shell microparticles loading curcumin for enhanced ulcerative colitis alleviating efficacy

Background

The oral colon-targeting drug delivery vehicle is vital for the efficient application of curcumin (Cur) in ulcerative colitis (UC) treatment because of its lipophilicity and instability in the gastrointestinal tract.

Methods

The core–shell microparticle (MP) system composed of eco-friendly materials, zein and shellac, was fabricated using a coaxial electrospray technique. In this manner, Cur was loaded in the zein core, with shellac shell coating on it. The colon-targeting efficiency and accumulation capacity of shellac@Cur/zein MPs were evaluated using a fluorescence imaging test. The treatment effects of free Cur, Cur/zein MPs, and shellac@Cur/zein MPs in acute experimental colitis were compared.

Results

With the process parameters optimized, shellac@Cur/zein MPs were facilely fabricated with a stable cone-jet mode, exhibiting standard spherical shape, uniform size distribution (2.84 ± 0.15 µm), and high encapsulation efficiency (95.97% ± 3.51%). Particularly, with the protection of shellac@zein MPs, Cur exhibited sustained drug release in the simulated gastrointestinal tract. Additionally, the in vivo fluorescence imaging test indicated that the cargo loaded in shellac@zein MPs improves the colon-targeting efficiency and accumulation capacity at the colonitis site. More importantly, compared with either free Cur or Cur/zein MPs, the continuous oral administration of shellac@Cur/zein MPs for a week could efficiently inhibit inflammation in acute experimental colitis.

Conclusion

The shellac@Cur/zein MPs would act as an effective oral drug delivery system for UC management.

Low-Intensity Focused Ultrasound-Augmented Multifunctional Nanoparticles for Integrating Ultrasound Imaging and Synergistic Therapy of Metastatic Breast Cancer

The metastasis of breast cancer is believed to have a negative effect on its prognosis. Benefiting from the remarkable deep-penetrating and noninvasive characteristics, sonodynamic therapy (SDT) demonstrates a whole series of potential leading to cancer treatment. To relieve the limitation of monotherapy, a multifunctional nanoplatform has been explored to realize the synergistic treatment efficiency. Herein, we establish a novel multifunctional nano-system which encapsulates chlorin e6 (Ce6, for SDT), perfluoropentane (PFP, for ultrasound imaging), and docetaxel (DTX, for chemotherapy) in a well-designed PLGA core-shell structure. The synergistic Ce6/PFP/DTX/PLGA nanoparticles (CPDP NPs) featured with excellent biocompatibility and stability primarily enable its further application. Upon low-intensity focused ultrasound (LIFU) irradiation, the enhanced ultrasound imaging could be revealed both in vitro and in vivo. More importantly, combined with LIFU, the nanoparticles exhibit intriguing antitumor capability through Ce6-induced cytotoxic reactive oxygen species as well as DTX releasing to generate a concerted therapeutic efficiency. Furthermore, this treating strategy actives a strong anti-metastasis capability by which lung metastatic nodules have been significantly reduced. The results indicate that the SDT-oriented nanoplatform combined with chemotherapy could be provided as a promising approach in elevating effective synergistic therapy and suppressing lung metastasis of breast cancer.

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.

Recent Progresses in Cancer Nanotherapeutics Design Using Artemisinins as Free Radical Precursors

Artemisinin and its derivatives (ARTs) are sort of important antimalarials, which exhibit a wide range of biological activities including anticancer effect. To solve the issues regarding poor solubility and limited bioavailability of ARTs, nanoformulation of ARTs has thus emerged as a promising strategy for cancer treatment. A common consideration on nanoARTs design lies on ARTs' delivery and controlled release, where ARTs are commonly regarded as hydrophobic drugs. Based on the mechanism that ARTs' activation relies on ferrous ions (Fe2+) or Fe2+-bonded complexes, new designs to enhance ARTs' activation have thus attracted great interests for advanced cancer nanotherapy. Among these developments, the design of a nanoparticle that can accelerate ARTs' activation has become the major consideration, where ARTs have been regarded as radical precursors. This review mainly focused on the most recent developments of ARTs nanotherapeutics on the basis of advanced drug activation. The basic principles in those designs will be summarized, and a few excellent cases will be also discussed in detail.

Fabrication of Polymeric Microparticles by Electrospray: The Impact of Experimental Parameters

Microparticles (MPs) with controlled morphologies and sizes have been investigated by several researchers due to their importance in pharmaceutical, ceramic, cosmetic, and food industries to just name a few. In particular, the electrospray (ES) technique has been shown to be a viable alternative for the development of single particles with different dimensions, multiple layers, and varied morphologies. In order to adjust these properties, it is necessary to optimize different experimental parameters, such as polymer solvent, voltage, flow rate (FR), type of collectors, and distance between the collector and needle tip, which will all be highlighted in this review. Moreover, the influence and contributions of each of these parameters on the design and fabrication of polymeric MPs are described. In addition, the most common configurations of ES systems for this purpose are discussed, for instance, the main configuration of an ES system with monoaxial, coaxial, triaxial, and multi-capillary delivery. Finally, the main types of collectors employed, types of synthesized MPs and their applications specifically in the pharmaceutical and biomedical fields will be emphasized. To date, ES is a promising and versatile technology with numerous excellent applications in the pharmaceutical and biomaterials field and such MPs generated should be employed for the improved treatment of cancer, healing of bone, and other persistent medical problems.