Effective Drug Delivery Research Articles

Intelligent Drug Delivery: Pioneering Stimuli-Responsive Systems to Revolutionize Disease Management- An In-depth Exploration.

In recent years, there has been an escalating interest in stimuli-responsive drug delivery systems (SRDDS) due to their ability to revolutionize the delivery of therapeutics. SRDDSs offer a multitude of benefits in comparison to conventional drug delivery systems (DDS), including spatiotemporal control of drug release, targeted delivery, and improved therapeutic efficacy. The development of various classes of stimuli-responsive DDS, such as pH-responsive, temperature-responsive, photo-responsive, redox responsive systems, has been propelled by advances in materials science, nanotechnology, and biotechnology. These systems exploit specific environmental or physiological cues to trigger drug release in a precisely controlled manner, making them highly promising for the treatment of various diseases. In this review article, an in-depth exploration of the principles, mechanisms, and applications of SRDDS in the context of diverse pathologies such as cancer, arthritis, Alzheimer's disease, atherosclerosis and tissue engineering has been provided. Furthermore, this article delves into the discussion of recent patents, market overview and the progress of research in clinical trials. Overall, this article underscores the transformative potential of SRDDS in enabling personalized, precise, and effective drug delivery for the treatment of the above-mentioned diseases.

Gold nanoclusters encapsulated microneedle patches with antibacterial and self‐monitoring capacities for wound management

AbstractThe management of infected wounds is always of great significance and urgency in clinical and biomedical fields. Recent efforts in this area are focusing on the development of functional wound patches with effective antibacterial, drug delivery, and sensor properties. Here, we present novel hyaluronic acid (HA) microneedle patches with these features by encapsulating aminobenzeneboronic acid‐modified gold nanoclusters (A‐GNCs) for infected wound management. The A‐GNCs loaded microneedle patches were derived from negative‐mold replication and showed high mechanical strength to penetrate the skin. The release of the A‐GNCs was realized by the degradation of HA, and the self‐monitor of the released actives was based on the dynamic bright orange fluorescence emitted from A‐GNCs under ultraviolet radiation. As the A‐GNCs could destroy bacteria membranes, the microneedle patches were with excellent in vitro antibiosis ability. Based on these features, we have demonstrated the bacteria inhibition, residual drug self‐monitoring, and wound healing promotion abilities of the microneedle patches in Escherichia coli‐ or Staphylococcus aureus‐infected wound management. These results indicated the great potential of such A‐GNCs loaded microneedle patches for clinical applications.

P116 Gastro-resistant microparticles for the oral delivery of Phycocyanin in the Inflammatory Bowel Disease therapy

Abstract Background Inflammatory Bowel Disease (IBD) is a chronically relapsing inflammation of the gastrointestinal tract, with ambiguous etiology. Oral route is the most common and acceptable approach for drug administration in the IBD treatment. However, it remains a challenge to maintain the stability of the drugs during oral treatment, particularly in the gastric environment, due its harsh conditions. In this context, the antioxidant and antiinflagmmatory properties of various natural compounds, as Phycocyanin (PC), a water-soluble bioactive molecule found in algae, can be strongly affected by factors as pH and temperature, inducing PC degradation and attenuating the curative effects. In this work, we produced a gastro-resistant microparticles (MPs) as controlled release systems for PC, and we aimed to compare its efficacy with free PC effects, on rat model of IBD. Methods The novel pharmaceutical system (SPC) was produced by microencapsulation technique, the spray-drying technique, using soy proteins (SPs) as natural excipients, aiming to improve the stability of the active ingredient and to ensure a modified release profile of PC. Rats were divided into groups and colitis was induced by intracolonic instillation of Dinitrobenzene sulfonic acid (DNBS, 20 mg/rat). Effects of preventive oral treatment of free PC or SPC were investigated, bioavailability was assessed and then body weight loss, stool consistency, colon weight/length index, myeloperoxidase activity (MPO), macroscopic damage and disease activity index (DAI) were determined. Results The SPC microparticle systems showed enhanced bioavailability of Phycocyanin, resulting in increased blood concentrations. The SPC system achieved the maximum AUC value and a modified release profile, particularly for gastro-resistant types, with a delayed Tmax of 5 hours, indicating their potential as a gastro-resistant formulation. Both PC and SPC pretreatments significantly ameliorated the severity of DNBS-induced colitis, however SPC pretreatment demonstrated enhanced activity vs PC. SPC rats showed a reduction of DAI, body weight loss and diarrhea incidence >15%, compared to PC (P<0.05); the ability of preventing the DNBS-induced macroscopic colonic damage and the MPO increase in SPC group were significantly higher than PC group (P<0.05) and also a tendency to improvement of colon weight/length index was observed. Conclusion In conclusion, the results of our research demonstrated that gastro-resistant microparticles (SPC) exhibit significantly improved therapeutic efficacy compared to orally administered free PC and can be developed as an effective new oral drug delivery system with controlled release profile in the treatment of IBD.

Tunable self-assembly of lipid-based block polymeric micelles with temperature-sensitive poly(vinylcaprolactam) shell for effective anticancer drug delivery

Lipids, as naturally occurring biomolecules have emerged as promising carriers for delivering various therapeutic agents. However, only a few attempts have been made in terms of their applications as amphiphilic block copolymers for anticancer drug delivery. In this work, a biocompatible micellar drug delivery system with fatty acid-based polymer core and temperature-sensitive shell was developed. A series of amphiphilic block copolymers poly(vinyl stearate)/poly(vinyl laurate)-b-poly(N-vinylcaprolactam) (PVS/PVL-b-PNVCL) were synthesized via microwave-assisted reversible addition-fragmentation chain transfer polymerization in a controlled fashion. By varying the fatty acid type and hydrophilic/hydrophobic block lengths, the self-assembly behaviour of the block copolymer micelles proved to be highly tunable in terms of their morphology and particle size. Nile Red and hydrophobic anticancer drug doxorubicin (DOX) were effectively incorporated into the micelles, demonstrating high drug loading capacity, good serum stability, and temperature-dependent drug release characteristics of the polymeric micelles. In vitro studies using cell models revealed that blank PVS -b-PNVCL micelles are biocompatible with different cell lines, while DOX-loaded micelles were internalized into and accumulated in the cells, showing a high cytotoxic effect against HeLa cells. These findings suggest an opportunity for the development of safe and efficient lipid-based micellar system for smart drug delivery and cancer treatments.

Temperature/redox dual-responsive self-assembled nanogels for targeting delivery of curcumol to enhance anti-tumor and anti-metastasis activities against breast cancer

Chemotherapy proves to be a successful method in treating primary breast cancer. Ironically, some commonly used chemotherapeutics may promote lung metastasis by increasing the activity of activating transcription factor 3 (ATF3). Thus, it is necessary to inhibit tumor metastasis while improving the anti-tumor effect of anti-cancer drugs. Herein, using curcumol (CUR) that possesses both anti-tumor and anti-metastasis activities as a model drug, we designed the nanogels based on temperature-responsive self-assembly and glutathione-triggered disassembly to address the abovementioned conflicts. Briefly, the copolymers (H-SS-P) were synthesized by coupling poly (N-isopropylacrylamide) onto hyaluronic acid (HA) via a disulfide bond-containing linker cystamine dihydrochloride. Copolymers could self-assemble into regular spherical nanogels at 37 °C with a 40-nm particle size for PNIPAAm's thermosensitivity. Hydrophobic CUR could be automatically entrapped into the core of nanogels. The H-SS-P@CUR nanogels could release drugs quickly upon exposure to the reductive tumor microenvironment. The superior efficacy of H-SS-P@CUR on inhibiting tumor growth was validated through assays both in vivo and in vitro. Moreover, nanogels may better down-regulate the expression of ATF3 protein by enhancing the cell uptake and tumor targeting of CUR, thereby significantly improving the anti-metastasis effect of CUR. This work not only proposed a novel strategy to simplify the preparation process of nanogels but also achieved effective drug delivery with enhanced anti-cancer and anti-metastasis effects.

Unveiling Spanlastics as a Novel Carrier for Drug Delivery: A Review.

Innovative colloidal preparations that can alter the pharmacological properties of drugs have been made possible by the advancement of nanotechnology. Recent advances in the sciences of the nanoscale have led to the creation of new methods for treating illnesses. Developments in nanotechnology may lessen the side effects of medicine by using effective and regulated drug delivery methods. A promising drug delivery vehicle is spanlastics, an elastic nanovesicle that can transport a variety of drug compounds. Spanlastics have expanded the growing interest in many types of administrative pathways. Using this special type of vesicular carriers, medications intended for topical, nasal, ocular, and trans-ungual treatments are delivered to specific areas. Their elastic and malleable structure allows them to fit into skin pores, making them ideal for transdermal distribution. Spanlastic is composed of non-ionic surfactants or combinations of surfactants. Numerous studies have demonstrated how spanlastics significantly improve, drug bioavailability, therapeutic effectiveness, and reduce medication toxicity. The several vesicular systems, composition and structure of spanlastics, benefits of spanlastics over alternative drug delivery methods, and the process of drug penetration via skin are all summarized in this paper. Additionally, it provides an overview of the many medications that may be treated using spanlastic vesicles. The primary benefits of these formulations were associated with their surface properties, as a variety of proteins might be linked to the look. For instance, procedure assessment and gold nanoparticles were employed as biomarkers for different biomolecules, which included tumor label detection. Anticipate further advancements in the customization and combining of spanlastic vesicles with appropriate zeta potential to transport therapeutic compounds to specific areas for enhanced disease treatment.

An Oral Nanomedicine Elicits In Situ Vaccination Effect against Colorectal Cancer.

Oral administration is the most preferred approach for treating colon diseases, and in situ vaccination has emerged as a promising cancer therapeutic strategy. However, the lack of effective drug delivery platforms hampered the application of in situ vaccination strategy in oral treatment of colorectal cancer (CRC). Here, we construct an oral core-shell nanomedicine by preparing a silk fibroin-based dual sonosensitizer (chlorin e6, Ce6)- and immunoadjuvant (imiquimod, R837)-loaded nanoparticle as the core, with its surface coated with plant-extracted lipids and pluronic F127 (p127). The resultant nanomedicines (Ce6/R837@Lp127NPs) maintain stability during their passage through the gastrointestinal tract and exert improved locomotor activities under ultrasound irradiation, achieving efficient colonic mucus infiltration and specific tumor penetration. Thereafter, Ce6/R837@Lp127NPs induce immunogenic death of colorectal tumor cells by sonodynamic treatment, and the generated neoantigens in the presence of R837 serve as a potent in situ vaccine. By integrating with immune checkpoint blockades, the combined treatment modality inhibits orthotopic tumors, eradicates distant tumors, and modulates intestinal microbiota. As the first oral in situ vaccination, this work spotlights a robust oral nanoplatform for producing a personalized vaccine against CRC.

The Potential of Quality Target Product Profile in the Optimization of Nanoemulsions

Abstract: The application of Quality Target Product Profile (QTPP) in optimizing nanoemulsion (NEM) shows immense potential in advancing pharmaceutical formulation design for effective drug delivery. By aligning QTPP with nanoemulsion attributes, this approach offers a pathway to tailored formulations that meet specific therapeutic objectives and responses. Incorporating QTPP facilitates informed choices in formulating design, covering pivotal factors like stability, drug re-lease kinetics, bioavailability, and precise targeting. Moreover, this review extensively explores the real-world application of QTPP-guided tactics in refining nanoemulsion optimization. It high-lights their pivotal role in anticipating and regulating in vivo responses, encompassing vital as-pects like pharmacokinetics and pharmacodynamics. By conducting thorough examinations of case studies and research outcomes, this article clarifies the effectiveness of aligning QTPP crite-ria with NEM characteristics. This approach fosters the creation of customized formulations pre-cisely suited to achieve distinct therapeutic objectives. This review amalgamates contemporary insights into harnessing QTPP for nanoemulsion optimization, illuminating its capacity to stream-line formulation design, amplify treatment effectiveness by desiring drug release, and catalyze transformative shifts in pharmaceutical research.

Novel chitosan and N-isopropylacrylamide-grafted-dextran-based microformulations as effective oral drug delivery system

Novel chitosan and N-isopropylacrylamide-grafted-dextran-based microformulations as effective oral drug delivery system

Nanoparticle-integrated dissolving microneedles for the co-delivery of R848/aPD-1 to synergistically reverse the immunosuppressive microenvironment of triple-negative breast cancer

Nowadays, effective immunotherapy against triple-negative breast cancer (TNBC) remains challenging due to the immunosuppressive tumor microenvironment. Immune checkpoint inhibitor is mostly employed to restore the activity of tumor-specific immune cells, which however brings little therapeutic outcome owing to the limited number of tumor-infiltrating CD8+ T cells and the inefficient delivery of immune drugs to the tumor tissue. Aiming to solve these problems, we herein constructed a tailor-made dissolving microneedle co-encapsulating the TLR7/8 agonist R848 and the immune checkpoint inhibitor aPD-1, termed αNP-RNP@DMN, and fabricated it as a transdermal drug delivery system. This well-designed microneedle patch, endowed with efficient tumor drug delivery ability, was able to mature tumor-infiltrating dendritic cells (TIDCs) and further promote the infiltration of CD8+ T cells into the tumor tissue with the aid of R848. Moreover, the introduction of aPD-1 blocked the programmed cell death protein 1/programmed cell death ligand 1(PD-1/PD-L1) immune checkpoints, synergistically reversing the immunosuppressive microenvironment of TNBC. In vivo therapeutic results demonstrated that αNP-RNP@DMN not only significantly prolonged the survival time of 4T1 tumor-bearing mice, but also inhibited tumor recurrence and lung metastasis after surgery, implying the great potential of this effective drug delivery system for enhanced immunotherapy of superficial tumors. Statement of significanceThe limited number of tumor-infiltrating CD8+ T cells and the inefficient delivery of immune drugs to the tumor tissue hinder the effective immunotherapy of triple-negative breast cancer (TNBC). Herein, a dissolving microneedle co-encapsulating TLR7/8 agonist R848 and immune checkpoint inhibitor aPD-1 was developed and fabricated as a transdermal drug delivery system. This tailor-made microneedle patch not only promoted drug accumulation in tumor sites in a safe and painless manner, but also lifted the immune-suppressive state of tumor-infiltrating dendritic cells (TIDCs). The activated TIDCs further enhanced T-cell infiltration into the tumor tissue, thus successfully boosting the therapeutic efficacy of aPD-1. This study demonstrated that this well-designed microneedle patch could be served as an effective drug delivery system for enhanced immunotherapy of TNBC.

In Vitro and In Vivo Evaluation of the Pathology and Safety Aspects of Three- and Four-Way Junction RNA Nanoparticles.

RNA therapeutics has advanced into the third milestone in pharmaceutical drug development, following chemical and protein therapeutics. RNA itself can serve as therapeutics, carriers, regulators, or substrates in drug development. Due to RNA's motile, dynamic, and deformable properties, RNA nanoparticles have demonstrated spontaneous targeting and accumulation in cancer vasculature and fast excretion through the kidney glomerulus to urine to prevent possible interactions with healthy organs. Furthermore, the negatively charged phosphate backbone of RNA results in general repulsion from negatively charged lipid cell membranes for further avoidance of vital organs. Thus, RNA nanoparticles can spontaneously enrich tumor vasculature and efficiently enter tumor cells via specific targeting, while those not entering the tumor tissue will clear from the body quickly. These favorable parameters have led to the expectation that RNA has low or little toxicity. RNA nanoparticles have been well characterized for their anticancer efficacy; however, little detail on RNA nanoparticle pathology and safety is known. Here, we report the in vitro and in vivo assessment of the pathology and safety aspects of different RNA nanoparticles including RNA three-way junction (3WJ) harboring 2'-F modified pyrimidine, folic acid, and Survivin siRNA, as well as the RNA four-way junction (4WJ) harboring 2'-F modified pyrimidine and 24 copies of SN38. Both animal models and patient serum were investigated. In vitro studies include hemolysis, platelet aggregation, complement activation, plasma coagulation, and interferon induction. In vivo studies include hematoxylin and eosin (H&E) staining, hematological and biochemical analysis as the serum profiling, and animal organ weight study. No significant toxicity, side effect, or immune responses were detected during the extensive safety evaluations of RNA nanoparticles. These results further complement previous cancer inhibition studies and demonstrate RNA nanoparticles as an effective and safe drug delivery vehicle for future clinical translations.

An Article on Curcumin Loaded Transferosomes as A Novel Drug Delivery System

Curcumin is a natural compound found in turmeric and has shown potential in treating a variety of diseases due to its anti-inflammatory and antioxidant properties. However, curcumin has low bioavailability and poor solubility in water, which limits its therapeutic efficacy. Transferosomes are specialized lipid vesicles that can encapsulate drugs and other bioactive molecules, allowing them to be delivered to specific target tissues. Curcumin, a natural compound found in turmeric, has been the subject of intense study due to its potential health benefits, including anti-inflammatory and antioxidant properties. Transferosomes are lipid-based nanoparticles that can encapsulate hydrophobic compounds like curcumin and improve their delivery to target tissues. They can also enhance the absorption of drugs through the skin or mucous membranes. Several studies have investigated the potential of curcumin loaded transferosomes in various applications, such as wound healing, cancer treatment, and anti-inflammatory therapy. These studies have shown promising results, indicating that transferosomes could be an effective drug delivery system for curcumin. However, more research is needed to optimize the formulation and improve the stability and shelf-life curcumin-loaded transferosomes. Additionally, the safety and toxicity of these nanoparticles need to be thoroughly evaluated before they can be used in clinical application. In our study we have observed drug content 4.47mg/ml and EE% was found to be 94.8%, the percentage of drug release of curcumin transferosomes was observed as 30.8%at time period of 4hr.

Systemic Treatment with Fas-Blocking Peptide Attenuates Apoptosis in Brain Ischemia.

Apoptosis plays a crucial role in neuronal injury, with substantial evidence implicating Fas-mediated cell death as a key factor in ischemic strokes. To address this, inhibition of Fas-signaling has emerged as a promising strategy in preventing neuronal cell death and alleviating brain ischemia. However, the challenge of overcoming the blood-brain barrier (BBB) hampers the effective delivery of therapeutic drugs to the central nervous system (CNS). In this study, we employed a 30 amino acid-long leptin peptide to facilitate BBB penetration. By conjugating the leptin peptide with a Fas-blocking peptide (FBP) using polyethylene glycol (PEG), we achieved specific accumulation in the Fas-expressing infarction region of the brain following systemic administration. Notably, administration in leptin receptor-deficient db/db mice demonstrated that leptin facilitated the delivery of FBP peptide. We found that the systemic administration of leptin-PEG-FBP effectively inhibited Fas-mediated apoptosis in the ischemic region, resulting in a significant reduction of neuronal cell death, decreased infarct volumes, and accelerated recovery. Importantly, neither leptin nor PEG-FBP influenced apoptotic signaling in brain ischemia. Here, we demonstrate that the systemic delivery of leptin-PEG-FBP presents a promising and viable strategy for treating cerebral ischemic stroke. Our approach not only highlights the therapeutic potential but also emphasizes the importance of overcoming BBB challenges to advance treatments for neurological disorders.

Degradation and Erosion of Metal-Organic Frameworks: Comparative Study of a NanoMIL-100 Drug Delivery System.

To make a drug work better, the active substance can be incorporated into a vehicle for optimal protection and control of the drug delivery time and space. For making the drug carrier, the porous metal-organic framework (MOF) can offer high drug-loading capacity and various designs for effective drug delivery performance, biocompatibility, and biodegradability. Nevertheless, its degradation process is complex and not easily predictable, and the toxicity concern related to the MOF degradation products remains a challenge for their clinical translation. Here, we describe an in-depth molecular and nanoscale degradation mechanism of aluminum- and iron-based nanoMIL-100 materials exposed to phosphate-buffered saline. Using a combination of analytical tools, including X-ray photoelectron spectroscopy, nuclear magnetic resonance spectroscopy, small-angle X-ray scattering, and electron microscopy, we demonstrate qualitatively and quantitatively the formation of a new coordination bond between metal(III) and phosphate, trimesate release, and correlation between these two processes. Moreover, the extent of material erosion, i.e., bulk or surface erosion, was examined from the transformation of nanoparticles' surface, morphology, and interaction with water. Similar analyses show the impact of drug loading and surface coating on nanoMIL-100 degradation and drug release as a function of the metal-ligand binding strength. Our results indicate how the chemistry of nanoMIL-100(Al) and nanoMIL-100(Fe) drug carriers affects their degradation behaviors in a simulated physiological medium. This difference in behavior between the two nanoMIL-100s enables us to better correlate the nanoscale and atomic-scale mechanisms of the observed phenomena, thus validating the presented multiscale approach.

The regulatory mechanisms of cerium oxide nanoparticles in oxidative stress and emerging applications in refractory wound care.

Cerium oxide nanoparticles (CeNPs) have emerged as a potent therapeutic agent in the realm of wound healing, attributing their efficacy predominantly to their exceptional antioxidant properties. Mimicking the activity of endogenous antioxidant enzymes, CeNPs alleviate oxidative stress and curtail the generation of inflammatory mediators, thus expediting the wound healing process. Their application spans various disease models, showcasing therapeutic potential in treating inflammatory responses and infections, particularly in oxidative stress-induced chronic wounds such as diabetic ulcers, radiation-induced skin injuries, and psoriasis. Despite the promising advancements in laboratory studies, the clinical translation of CeNPs is challenged by several factors, including biocompatibility, toxicity, effective drug delivery, and the development of multifunctional compounds. Addressing these challenges necessitates advancements in CeNP synthesis and functionalization, novel nano delivery systems, and comprehensive bio effectiveness and safety evaluations. This paper reviews the progress of CeNPs in wound healing, highlighting their mechanisms, applications, challenges, and future perspectives in clinical therapeutics.

Penetration enhancers strengthen tough hydrogel bioadhesion and modulate locoregional drug delivery.

The human body possesses natural barriers, such as skin and mucosa, which limit the effective delivery of therapeutics and integration of medical devices to target tissues. Various strategies have been deployed to breach these barriers mechanically, chemically, or electronically. The development of various penetration enhancers (PEs) offers a promising solution due to their ability to increase tissue permeability using readily available reagents. However, existing PE-mediated delivery methods often rely on weak gel or liquid drug formulations, which are not ideal for sustained local delivery. Hydrogel adhesives that can seamlessly interface biological tissues with controlled drug delivery could potentially resolve these issues. Here, we demonstrate that tough adhesion between drug-laden hydrogels and biological tissue (e.g. skin and tumours) can lead to effective local delivery of drugs deep into targeted tissues by leveraging the enhanced tissue penetration mediated by PEs. The drug release profile of the hydrogel adhesives can be fine-tuned by further engineering the nanocomposite hydrogel matrix to elute chemotherapeutics from 2 weeks to 2 months. Using a 3D tumour spheroid model, we demonstrated that PEs increased the cancer-killing effectiveness of doxorubicin by facilitating its delivery into tumour microtissues. Therefore, the proposed tough bioadhesion and drug delivery strategy modulated by PEs holds promise as a platform technique to develop next-generation wearable and implantable devices for cancer management and regenerative medicine.

Nanotechnology-based delivery of therapeutics through the intranasal pathway and the blood-brain barrier for Alzheimer's disease treatment.

Background: drugs for Alzheimer's disease (AD) fail to exhibit efficacy in clinical trials for a number of reasons, a major one being blood-brain barrier (BBB) permeability. Meanwhile, the increasing incidence of this disease emphasizes the need for effective therapeutics. Herein, we discuss novel nanoplatform technologies developed for the effective delivery of AD drugs by traversing the BBB. Main text: the interfacial and surface chemistry of nanomaterials is utilized in several industries, including pharmaceutical, and has drawn considerable attention in the field of nanotechnology. Various reports have suggested the potential of nanotechnology for AD treatment, describing unique drug carriers that improve drug stability and solubility while maintaining therapeutic dosages. These nanotechnologies are harnessed for the transport of drugs across the BBB, with or without surface modifications. We also discuss the transfer of drugs via the nose-to-brain pathway, as intranasal delivery enables direct drug distribution in the brain. In addition, nanomaterial modifications that prolong drug delivery and improve safety following intranasal administration are addressed. Conclusion: although several studies have yielded promising results, limited efforts have been undertaken to translate research findings into clinical contexts. Nevertheless, nanomaterials hold considerable potential for the development of novel effective therapeutic solutions against AD.

Exosomes encapsulated in hydrogels for effective central nervous system drug delivery.

The targeted delivery of pharmacologically active molecules, metabolites, and growth factors to the brain parenchyma has become one of the major challenges following the onset of neurodegeneration and pathological conditions. The therapeutic effect of active biomolecules is significantly impaired after systemic administration in the central nervous system (CNS) because of the blood-brain barrier (BBB). Therefore, the development of novel therapeutic approaches capable of overcoming these limitations is under discussion. Exosomes (Exo) are nano-sized vesicles of endosomal origin that have a high distribution rate in biofluids. Recent advances have introduced Exo as naturally suitable bio-shuttles for the delivery of neurotrophic factors to the brain parenchyma. In recent years, many researchers have attempted to regulate the delivery of Exo to target sites while reducing their removal from circulation. The encapsulation of Exo in natural and synthetic hydrogels offers a valuable strategy to address the limitations of Exo, maintaining their integrity and controlling their release at a desired site. Herein, we highlight the current and novel approaches related to the application of hydrogels for the encapsulation of Exo in the field of CNS tissue engineering.

A co-assembly process for high strength and injectable dual network gels with sustained doxorubicin release performance.

Adopting a non-covalent co-assembly strategy shows great potential in loading drugs efficiently and safely in drug delivery systems. However, finding an efficient method for developing high strength gels with thixotropic characteristics is still challenging. In this work, by hybridizing the low molecular weight gelator fluorenylmethyloxycarbonyl-phenylalanine (Fmoc-F) (first single network, 1st SN) and alginate (second single network, 2nd SN) into a dual network (DN) gel, gels with high strength as well as thixotropy were prepared efficiently. The DN gels showed high strength (103 Pa in SN gels and 105 Pa in DN gels) and thixotropic characteristics (yield strain <25%; recovery ratio >85% within 100 seconds). The application performance was verified by loading doxorubicin (DOX), showing better encapsulation capacity (77.06% in 1st SN, 59.11% in 2nd SN and 96.71% in DN) and sustained release performance (lasting one week under physiological conditions) than single network gels. Experimental and DFT results allowed the elaboration of the specific non-covalent co-assembly mechanism for DN gel formation and DOX loading. The DN gels were formed by co-assembly driven by H-bond and π-π stacking interactions and then strengthened by Ca2+-coupling. Most DOX molecules co-assembled with Fmoc-F and alginate through π-π stacking and H-bond interactions (DOX-I), with a few free DOX molecules (DOX-II) left. Proven by the release dynamics test, DOX was released through a diffusion-erosion process, in an order of DOX-I first and then DOX-II. This work suggests that non-covalent co-assembly is a useful technique for effective material strengthening and drug delivery.

Quantification of rifampicin loaded into inhaled polymeric nanoparticles by reversed phase high-performance liquid chromatography in pulmonary nonphagocytic cellular uptake.

Rifampicin is an antibiotic effective against both Gram-negative and Gram-positive bacteria and is commonly used as a first-line treatment for tuberculosis caused by Mycobacterium tuberculosis. In this study, a reversed-phase high-performance liquid chromatography method was developed and validated to assess rifampicin, either free or combined with ascorbic acid, loaded into chitosan/Tween 80-coated alginate nanoparticles. The method utilized a reversed-phase C18 Restek column with specific chromatographic conditions: a mobile phase of 60 : 40 ratios of methanol/buffer phosphate (pH 7.0), at a flow rate of 0.8 mL min-1, and an injection volume of 15 μL. rifampicin and the internal standard (rifamycin) had retention times of 4.0 and 2.5 min, respectively, and were detected at 334 nm. The method demonstrated the stability of stored samples after freezing-thawing cycles and specificity for rifampicin, even in the presence of degradation products from stress conditions. The high-performance liquid chromatography method was found to be specific, precise, robust, and sensitive. Results indicated that rifampicin accumulation and uptake kinetics varied based on cell type, formulation (free or loaded in nanoparticles), rifampicin concentration, and incubation time. Confocal fluorescence microscopy images supported these findings, showing isothiocyanate fluorescein nanoparticles distribution in different intracellular regions depending on the cell type used. The societal impact of this research lies in its potential to advance the treatment of respiratory infectious diseases, such as tuberculosis, through the development of more effective and specific drug delivery methods. By optimizing the way drugs, particularly rifampicin in this case, interact with lung cells, we aim to achieve greater treatment efficacy and alleviate the overall burden of disease. Furthermore, our study offers novel insights into the intracellular behavior of rifampin from polymeric nanoparticles, paving the way for personalized medicine approaches in the treatment of respiratory infections. This dual focus on social impact and innovation underscores our commitment to improving global health outcomes and addressing pressing public health challenges.