Delivery Capability Research Articles

3D-Printed Hydrogel Scaffolds Loaded with Flavanone@ZIF-8 Nanoparticles for Promoting Bacteria-Infected Wound Healing

Bacterial-infected skin wounds caused by trauma remain a significant challenge in modern medicine. Clinically, there is a growing demand for wound dressings with exceptional antibacterial activity and robust regenerative properties. To address the need, this study proposes a novel multifunctional dressing designed to combine efficient gas exchange, effective microbial barriers, and precise drug delivery capabilities, thereby promoting cell proliferation and accelerating wound healing. This work reports the development of a 3D-printed hydrogel scaffold incorporating flavanone (FLA)-loaded ZIF-8 nanoparticles (FLA@ZIF-8 NPs) within a composite matrix of κ-carrageenan (KC) and konjac glucomannan (KGM). The scaffold forms a stable dual-network structure through the chelation of KC with potassium ions and intermolecular hydrogen bonding between KC and KGM. This dual-network structure not only enhances the mechanical stability of the scaffold but also improves its adaptability to complex wound environments. In mildly acidic wound conditions, FLA@ZIF-8 NPs release Zn2+ and flavanone in a controlled manner, providing sustained antibacterial effects and promoting wound healing. In vivo studies using a rat full-thickness infected wound model demonstrated that the FLA@ZIF-8/KC@KGM hydrogel scaffold significantly accelerated wound healing, showcasing its superior performance in the treatment of infected wounds.

Liposomal Drug Delivery System for the Management of Prostate Cancer: An Update

Abstract: Prostate cancer is a significant health concern affecting a large population of males worldwide. Liposomes, with their versatile properties and drug delivery capabilities, hold promise as a targeted and efficient delivery system for prostate cancer treatment. Various studies have explored different liposomal formulations loaded with anticancer agents to improve drug efficacy, reduce side effects, and enhance targeted delivery to prostate cancer cells. Future research in this area should focus on refining liposomal formulations to maximize drug encapsulation, stability, and specific targeting of prostate cancer cells. Understanding the tumor microenvironment and utilizing stimuli-responsive liposomes can further enhance drug release at the targeted site. Additionally, investigating the biodistribution and pharmacokinetics of liposomal drug delivery systems in vivo will provide valuable insights into their efficacy and potential for clinical translation. Overall, liposome-based drug delivery systems have the potential to revolutionize prostate cancer treatment, ultimately improving patient outcomes and quality of life. Further advancements and continued research in this field will contribute to the development of effective and personalized therapeutic strategies for prostate cancer patients.

Integrated Performance Assessment of Prefabricated Component Suppliers Based on a Hybrid Method Using Analytic Hierarchy Process–Entropy Weight and Cloud Model

Prefabricated construction has garnered widespread attention worldwide. As an important part in purchasing management, prefabricated component suppliers (PCSs) undertake the bulk of the work and responsibility in the supply chain from on-site to off-site. Therefore, it is crucial and necessary to establish a decision-making framework to comprehensively evaluate the performance of PCSs. This study proposed a set of performance indicators for PCSs, including component quality, cost, delivery capability, service level, enterprise development potential, and enterprise cooperation potential. A hybrid method was established to evaluate the integrated performance of PCSs based on Analytic Hierarchy Process (AHP)–entropy weight and cloud model. It integrated the AHP and entropy weight method to calculate indicator weights, while the cloud model was employed to transform qualitative characteristics into quantitative ones. To verify the feasibility of this method, an empirical study was subsequently conducted using a typical case from China. The obtained results demonstrate that the overall performance of Supplier A lies at the “good” level, with the similarity index between the comprehensive cloud model and the standard cloud model within the good range, at 0.4045. Among the six primary indicators, quality performance scored the highest at 0.65, meeting the “excellent” standard. It can be seen that the hybrid approach of AHP–entropy weight and cloud model accurately and effectively demonstrates the integrated performance of PCSs. The main aim of this study was to establish a comprehensive system and develop a novel approach for evaluating the performance of PCSs within a hesitant fuzzy environment. The findings of this study can provide guidelines for researchers and the public to evaluate PCS performance, contributing significantly to the fields of supply chain management and construction engineering. Moreover, it provided a practical tool for professionals in the industry to enhance the supplier selection processes.

Bioinspired synthesis of virus-like particle-templated thin silica-layered nanocages with enhanced biocompatibility and cellular uptake as drug delivery carriers

The bioinspired synthesis of virus-like silica nanoparticles in biomedical applications makes it possible to utilize the cellular delivery capabilities of viruses while minimizing the cytotoxicity of inorganic silica. In this study, we developed a diatom-inspired method for synthesizing silica-layered nanocages utilizing R5 peptide-functionalized virus-like particles (VLPs). R5 peptides were genetically inserted into the F-G loop of human papillomavirus 16 L1 proteins (HPV16 L1-R5). HPV16 L1-R5 was self-assembled into VLPs under an acidic pH similar to native ones and exhibited ∼65 % drug encapsulation efficiency. The HPV16 L1-R5 VLP@silica nanocages (SiNPs) were synthesized through diatom-inspired silicification of HPV16 L1-R5 VLPs via intermolecular interaction of the R5 peptide and polyol. HPV16L1-R5 VLP@SiNPs displayed uniform, monodisperse particles with approximately 10 nm silica layer compared to HPV16 L1-R5 VLPs. HPV16 L1-R5 VLP@SiNPs showed high biocompatibility at high concentrations, unlike commercial mesoporous SiNPs. Furthermore, the virus-like HPV16 L1-R5 VLP@SiNPs resulted in approximately 2.5-fold increased cellular uptake efficiency compared to commercial mesoporous SiNPs. These results suggest that the thin silica layer on HPV16 L1-R5 VLPs retains cellular delivery capacity while reducing cytotoxicity. Our strategy presents an innovative method for synthesizing virus-like nanoparticles in biomedical applications, enhancing cellular delivery capacity and biocompatibility.

Mediating Effect of Delivery Capability on Public-Private Partnership Financing Structure and Geothermal Energy Development Project Completion in Kenya

Investments in Geothermal Energy Development Projects (GEPs) are still considered high-risk and capital-intensive with unpredictable completion even amidst the adoption of Public Private Partnership (PPP) financing models particularly in sub-Saharan Africa (SSA). Numerous GEP completion bottlenecks affecting timely project completion have been documented lately; these challenges have caused delayed delivery of critical path milestones, project stalling, and even outright project failures. Recent empirical studies focused more on developed countries' longitudinal secondary databases covering the wider energy sector, with minimal attention paid to the situation of GEPs in developing countries. Anchored on the positivism and pragmatism foundations, this study examined the mediating influence of delivery capability on the relationship between PPP financing structure and the completion of GEPs in Kenya. Using a census survey design, data from 48 geothermal energy projects (private sector project managers and implementation team leaders from the public sector) and key informants was collected and analyzed using mixed methods. Data triangulation and diagnostic tests were performed. The results and findings revealed that while PPP financing structure alone explains 43.9% of the variance in project completion, the inclusion of delivery capability substantially increases the explained variance to 66.1%. A balanced PPP financing structure and delivery capability have statistically significant effects on project completion outcomes, with delivery capability (β = 0.579) having a stronger isolated effect than the PPP financing structure (β = 0.326). The reduction in the PPP financing structure coefficient from the first to the second model suggests that some of its effect is shared with or mediated by delivery capability. The study concluded that completing PPP-financed GEPs requires an integrated approach that considers both predictor variables: A balanced PPP financing structure comprising private equity, commercial and concessional loans, grants and government contributions; and strong delivery capability including geological, technological, PPP modelling and agile project management competencies. Geothermal sector-specific government support measures and industry recommendations are provided to enhance the completion of PPP-financed geothermal energy development projects mainly in the SSA region.

Outer Membrane Vesicle-Cancer Hybrid Membrane Coating Indocyanine Green Nanoparticles for Enhancing Photothermal Therapy Efficacy in Tumors.

Cell membrane-coated nanomaterials are increasingly recognized as effective in cancer treatment due to their unique benefits. This study introduces a novel hybrid membrane coating nanoparticle, termed cancer cell membrane (CCM)-outer membrane vesicle (OMV)@Lip-indocyanine green (ICG), which combines CCMs with bacterial OMV to encapsulate ICG-loaded liposomes. Comprehensive analyses were conducted to assess its physical and chemical properties as well as its functionality. Demonstrating targeted delivery capabilities and good biocompatibility, CCM-OMV@Lip-ICG nanoparticles showed promising photothermal and immunotherapeutic effects in tumor models. By inducing hyperthermia-induced tumor therapy and bolstering antitumor immunity, CCM-OMV@Lip-ICG nanoparticles exhibit a synergistic therapeutic effect, providing a new perspective for the management of cancer.

Design and Synthesis of Triazine-Based Hydrogel for Combined Targeted Doxorubicin Delivery and PI3K Inhibition.

Melanoma, an aggressive skin cancer originating from melanocytes, presents substantial challenges due to its high metastatic potential and resistance to conventional therapies. Hydrogels, three-dimensional networks of hydrophilic polymers with high water-retention capacities, offer significant promise for controlled drug delivery applications. In this study, we report the synthesis and characterization of hydrogelators based on the triazine molecular scaffold, which self-assemble into fibrous networks conducive to hydrogel formation. Rheological analysis confirmed their hydrogelation properties, while microscopic techniques including FE-SEM and FEG-TEM provided insights into their morphological networks. The drug delivery capability of these hydrogelators was evaluated using doxorubicin, a widely employed anticancer agent, demonstrating enhanced biocompatibility and reduced side effects compared to free doxorubicin. Additionally, the hydrogelators exhibited inhibitory activity against phosphoinositide 3-kinase (PI3K), a key enzyme frequently mutated in cancer, and also involved in melanoma progression. The dual functionality of this delivery system - controlled drug release and PI3K inhibition - highlights the potential of triazine-based hydrogelators as innovative therapeutic platforms for melanoma treatment.

High-throughput screening-based design of multifunctional natural polyphenol nano-vesicles to accelerate diabetic wound healing

Oxidative stress is a major pathological factor that impedes the diabetic wound healing process. Procyanidins (PC) form nanoparticle-vesicles (PPNs) through hydrogen bonding and exhibit good drug delivery capability; however, their application in diabetic wounds is unsatisfactory. To meet the antioxidant needs for treating, high-throughput screening in the natural product library (NPL) under in vitro oxidative stress conditions was conducted to enhance the antioxidant activity of PPNs. HUVECs treated with tert-Butyl Hydroperoxide (TBHP) were established as screening model in vitro. Baicalein (BAI) was identified from over 600 products in the library as the most effective one to combat oxidative stress. Further study showed that PC and BAI may react in equal proportions to synthesize new vesicles, named BAI-PC Polyphenolic nanovesicles (BPPNs), which possess reactive oxygen species (ROS) responsive and antioxidant effects. Network pharmacology indicated that in diabetic wounds, the target genes of PC are mainly enriched in the vascular endothelial growth factor (VEGF)-related pathways, while BAI primarily regulates tyrosine phosphorylation. The complementarity between the two has been validated in both in vitro and in vivo experiments. In summary, the antioxidant drug BAI, identified through high-throughput screening of NPL, could optimize the biological function of PPNs; the newly-synthesized BPPNs may accelerate diabetic wound healing through dual mechanisms of promoting angiogenesis and combating oxidative stress.Graphical abstract

Poly(2-hydroxyethyl methacrylate-co-methacrylated hyaluronan-β-cyclodextrin) hydrogel: A potential contact lens material with high hydrophilicity, good mechanical properties and sustained drug delivery

A novel poly(2-hydroxyethyl methacrylate-co-methacrylated hyaluronan-β-cyclodextrin) [p(HEMA-co-mHA-β-CD)] hydrogel was developed as a potential contact lens for ophthalmic disease. The hydrogel was synthesized from the copolymerization of 2-hydroxyethyl methacrylate (HEMA) monomer and mHA-β-CD as a hydrophilic macromolecular crosslinker. By adjusting the methacrylate substitution degree in hyaluronan (20–29 %) and the mHA-β-CD content (5–11 %), transparent p(HEMA-co-mHA-β-CD) hydrogels were achieved. p(HEMA-co-m20HA-β-CD) hydrogels exhibited an enhanced tensile modulus (from 0.35 to 0.88 MPa) with a decreased elongation at break (from 255 % to 108 %), meanwhile they showed increased hydrophilicity with a decreased water contact angle (from 83.4° to 48.6°) and an increased equilibrium water content (from 38.2 % to 46.4 %). Increasing the mHA-β-CD content resulted in a higher encapsulation and cumulative release of hydrophilic levofloxacin hydrochloride or hydrophobic puerarin, due to the improved hydrophilicity and the formation of β-CD/drug inclusion complexes. Compared with pHEMA hydrogel, p(HEMA-co-m20HA-β-CD) hydrogels better inhibited the deposition of lysozyme and bovine serum albumin, and the bacterial adhesion against S. aureus and E. coli. The hydrogels were stable at physiological conditions and non-toxic to immortalized human keratinocytes. With good mechanical properties, tear protein deposition resistance, antibacterial activity, and sustained drug delivery capabilities, p(HEMA-co-m20HA-β-CD) hydrogels were identified as a promising contact lens material for eye diseases.

Chitosan based injectable cryospheres as a potential biopolymeric carrier for drug delivery systems: Characterization, biocompatibility and drug release

Three-dimensional scaffolds with the right design to support cell metabolism and the right physico-chemical, mechanical, and biological qualities have become more interesting for tissue engineering because of the complexity and diversity of the tissues involved. Moreover, three-dimensional scaffolds with tuneable drug delivery capabilities have drawn more attention in the field of soft tissue engineering. In this research, chitosan-based microspheres (called cryospheres) were fabricated in spherical shapes micron-sized with highly interconnected porous structures as a result of combining emulsification and cryogelation methods. The characterization of cryospheres was evaluated using morphological, physicochemical, and biological analyses. According to the results of the in vitro and in vivo biocompatibility investigation, the microspheres had no toxic effects on cell survival, and they even enhanced cell viability at the implantation site when compared to the control group. After the cryospheres were characterized, research was done on drug loading, drug release, and release processes using two distinct dyes (Nile Red: NR and Rhodamine-B: RB) in simulated body fluids (simulated intestinal, stomach, and tear fluids). The results showed that the maximum drug loading capacities for RB and NR were 89.32 ± 1.57 % and 61.51 ± 0.70 %, respectively. This study contributed to the development of minimally invasive biomaterials that have the potential to provide both drug release and tissue formation/regeneration at damaged implantation sites by carrying not only drugs but also active substances such as hormones/growth factors that will trigger new tissue formation.

EFFECT OF PUBLIC PRIVATE PARTNERSHIP FINANCING STRUCTURE ON COMPLETION OF GEOTHERMAL ENERGY DEVELOPMENT PROJECTS IN KENYA

Objective: To determine the effect of Public Private Partnership (PPP) financing structure on the completion of geothermal energy development projects in Kenya. Theoretical Framework: The study used agency and public choice theories to analyze the dynamics between PPP financing structure and completion of geothermal energy development projects. Methodology: A cross-sectional census survey in Kenya surveyed 48 geothermal energy development projects, collecting quantitative data through structured questionnaires and qualitative insights from industry regulators, financiers, and practitioners. A combination of descriptive, correlation, and linear regression statistical models were applied. Multiple diagnostics tests and data triangulation were performed. Results and Discussion: The study results provide strong statistical evidence depicting a positive relationship between PPP financing structure and the completion of geothermal energy development projects in Kenya. The findings suggest that as the level of PPP involvement increases, so does the likelihood of faster project completion. The study also reveals that a balanced PPP financing structure has a substantial effect on the completion of geothermal energy development projects. The analysis demonstrates that a hybrid PPP financing structure comprising recommended proportions of private and government equity, commercial and concessional loans, hybrid finance, and grants significantly affects project completion outcomes. Research Implications: The study emphasizes the significance of a structured PPP financing model, comprising private and government equity, concessional and commercial loans, hybrid finance, and mixed grants, in mitigating inherent PPP risks for enhanced project completion outcomes. In addition, effective government support measures and robust delivery capability of developers jointly influence the two variables in a significant manner. Originality/Value: This study uniquely analyzes the influence of PPP financing structure on the completion of geothermal energy development projects in Kenya, integrating quantitative and qualitative data for a comprehensive perspective, thus offering essential insights for stakeholders.

High-throughput synthesis and optimization of ionizable lipids through A3 coupling for efficient mRNA delivery

BackgroundThe efficacy of mRNA-based vaccines and therapies relies on lipid nanoparticles (LNPs) as carriers to deliver mRNA into cells. The chemical structure of ionizable lipids (ILs) within LNPs is crucial in determining their delivery efficiency.ResultsIn this study, we synthesized 623 alkyne-bearing ionizable lipids using the A3 coupling reaction and assessed their effectiveness in mRNA delivery. ILs with specific structural features—18-carbon alkyl chains, a cis-double bond, and ethanolamine head groups—demonstrated superior mRNA delivery capabilities. Variations in saturation, double bond placement, and chain length correlated with decreased efficacy. Alkynes positioned adjacent to nitrogen atoms in ILs reduced the acid dissociation constant (pKa) of LNPs, thereby hindering mRNA delivery efficiency. Conversion of alkynes to alkanes significantly enhanced mRNA delivery of ILs both in vitro and in vivo. Moreover, combining optimized ILs with cKK-E12 yields synergistic LNPs that showed markedly augmented mRNA expression levels in vivo.ConclusionsOverall, our study provides insights into the structure–function relationships of ILs, providing a foundation for the rational design of ILs to enhance the efficacy of LNPs in mRNA delivery.Graphical

Surface Coating of ZIF-8 Nanoparticles with Polyacrylic Acid: A Facile Approach to Enhance Chemical Stability for Biomedical Applications.

Nanoparticles of zeolitic imidazole framework-8 (ZIF-8 NPs), which are the subclass of metal-organic frameworks consisting of Zn ion and 2-methylimidazole, have been identified as promising drug carriers since their large microporous structure is suited for encapsulating hydrophobic drug molecules. However, one of the limitations of ZIF-8 NPs is their low stability in physiological solutions, especially in the presence of water and phosphate anions. These molecules can interact with the coordinatively unsaturated Zn sites at the external surface to induce the degradation of ZIF-8 NPs. In this study, herein a facile approach is reported to enhance the chemical stability of ZIF-8 NPs by surface coating with polyacrylic acid (PAA). The PAA-coated ZIF-8 (PAA-ZIF-8) NPs are prepared by mixing ZIF-8 NPs and PAA in water. PAA coating inhibits the degradation of ZIF-8 NPs in water as well as phosphate-buffered saline over 6 days, which seems to be due to the coordination of carboxyl groups of PAA to the reactive Zn sites. Furthermore, the PAA-ZIF-8 NPs loaded with the anticancer drug doxorubicin (Dox) show cytotoxicity in human colon cancer cells. These results clearly show the feasibility of the PAA coating approach to improve the chemical stability of ZIF-8 NPs without impairing their drug delivery capability.

Development and Evaluation of a Novel Biodegradable Poly(amidoamine) with Bis(guanidinium) and Benzene Ring Structures for Enhanced Gene Delivery

Cationic polymer carriers have shown promise in non-viral gene delivery but face challenges such as low transfection efficiency and high toxicity. To address these issues, we synthesized a novel biodegradable poly(amidoamine) (PAA) cationic polymer, 4-(4-biguanide benzoylamino)butylamine-N,N’-bis(acryloyl)cystamine (PDAB-CBA). This polymer incorporates bis(guanidinium) groups and a hydrophobic benzene ring to enhance membrane affinity and hydrophobic interactions, respectively, thereby improving gene delivery performance. The inclusion of disulfide bonds in the polymer’s backbone imparts reductive response properties, allowing for degradation into small molecular weight fragments within cellular environments and reducing cytotoxicity. Our studies demonstrated that PDAB-CBA formed stable, uniform nanoparticles with plasmid DNA (pDNA), achieving an encapsulation efficiency of approximately 85% at a 6:1 weight ratio. The polyplexes had the average particle size of around 100 nm and the zeta potential between 25-35 mV, ensuring effective cellular uptake. PDAB-CBA/pDNA polyplexes exhibited higher transfection efficiency, with relative light units (RLU) greater than 1 × 105 at weight ratios of 6:1 to 24:1, compared to PEI/pDNA. Furthermore, PDAB-CBA demonstrated low cytotoxicity, maintaining cell viability above 80% at weight ratios below 24:1, and effectively protected genes against DNaseI degradation and heparin replacement. The primary endocytosis pathway for these polyplexes was clathrin-mediated endocytosis. Overall, PDAB-CBA exhibited superior gene delivery capabilities and a favorable safety profile, providing a new strategy for the design of efficient and low-toxicity gene delivery vectors.

INFLUENCE OF CAPABILITIES FOR RESOURCE MOBILIZATION ON THE PERFORMANCE OF THE LOCAL AUTHORITIES IN ZAMBIA

This study examined the influence of resource mobilization capabilities on the performance of local authorities in Zambia, addressing a decade-long performance challenge despite various government interventions. Using a correlational research design with a sample of 736 employees from 116 local authorities, the study tested the hypothesis that there is no statistically significant influence of resource mobilization capabilities on the financial performance of local authorities. Data collected through a structured questionnaire and analyzed using multiple linear regression revealed a significant positive relationship between capabilities for resource mobilization and local authorities' performance (B = 0.272, t = 6.516, p < .001), with the model explaining 63.7% of the performance variance. While local authorities demonstrated strengths in developing annual work plans, they struggled to provide all required public services. The study concludes that resource mobilization capabilities significantly influence local authorities' performance in Zambia and recommends enhancing resource mobilization strategies, improving service delivery capabilities, promoting knowledge sharing among local authorities, investing in technology-enabled systems for revenue collection and management, and implementing standardized performance management practices to address the identified performance gaps and improve overall public service delivery.<p> </p><p><strong> Article visualizations:</strong></p><p><img src="/-counters-/soc/0745/a.php" alt="Hit counter" /></p>

Exploring the Interaction of Lipid Bilayers with Curcumin-Laponite Nanoparticles: Implications for Drug Delivery and Therapeutic Applications.

Curcumin, the active compound in turmeric, is renowned for its anti-inflammatory, antioxidant, and antimicrobial properties, making it beneficial for treating conditions like arthritis, neurodegenerative diseases, and various cancers. Despite its promising therapeutic potential, curcumin's poor bioavailability-due to its rapid metabolism and low solubility-limits its clinical efficacy. To address this, recent research has focused on enhancing curcumin delivery using nanoparticles, liposomes, and novel nanomaterials. Among these, laponite, a synthetic nanoclay, has shown promise in improving curcumin delivery due to its unique properties, including large surface area, dual charge, and stability in solution. This study explores the use of curcumin-laponite nanoparticles as carrier vehicles for controlled delivery to in vitro model membranes. Utilizing advanced techniques such as neutron reflectometry, atomic force microscopy, quartz crystal microbalance with dissipation, and infrared spectroscopy, the interaction between curcumin-laponite nanoparticles and solid-supported lipid bilayers is monitored, revealing enhanced stability and controlled release of curcumin across the membrane. These findings pave the way for the development of curcumin-based therapies targeting cardiovascular, neurological, and oncological diseases, leveraging the synergistic effects of curcumin's biological activity and laponite's delivery capabilities.

Antioxidant hydrogels for the treatment of osteoarthritis: mechanisms and recent advances.

Articular cartilage has limited self-healing ability, resulting in injuries often evolving into osteoarthritis (OA), which poses a significant challenge in the medical field. Although some treatments exist to reduce pain and damage, there is a lack of effective means to promote cartilage regeneration. Reactive Oxygen Species (ROS) have been found to increase significantly in the OA micro-environment. They play a key role in biological systems by participating in cell signaling and maintaining cellular homeostasis. Abnormal ROS expression, caused by internal and external stimuli and tissue damage, leads to elevated levels of oxidative stress, inflammatory responses, cell damage, and impaired tissue repair. To prevent excessive ROS accumulation at injury sites, biological materials can be engineered to respond to the damaged microenvironment, release active components in an orderly manner, regulate ROS levels, reduce oxidative stress, and promote tissue regeneration. Hydrogels have garnered significant attention due to their excellent biocompatibility, tunable physicochemical properties, and drug delivery capabilities. Numerous antioxidant hydrogels have been developed and proven effective in alleviating oxidative stress. This paper discusses a comprehensive treatment strategy that combines antioxidant hydrogels with existing treatments for OA and explores the potential applications of antioxidant hydrogels in cartilage tissue engineering.

Application of nanoliposome as contrast agents for magnetic resonance imaging technique

AbstractLiposomes, nano‐sized vesicles primarily comprising phospholipids and cholesterol, have emerged as pivotal tools in medical imaging, notably in magnetic resonance imaging (MRI), due to their biocompatibility and ability to encapsulate diverse molecules. Tailorable properties like size, surface charge, and encapsulation capacity make liposomes ideal for targeted delivery of imaging agents and drugs to specific tissues, improving pharmacokinetics. As MRI contrast agent (CA) carriers, liposomes encapsulate gadolinium, mitigating toxicity and boosting relaxivity and circulation times. Functionalization with targeting ligands and stimuli‐responsive designs enhances their controlled release and targeted delivery capabilities, crucial for cancer imaging and therapy. Benefits include reduced toxicity, prolonged circulation, targeted delivery, enhanced bioavailability, and potential for multimodal imaging. Challenges remain, such as stability, clearance, and manufacturing intricacies, requiring further research. Nonetheless, liposomal MRI CAs hold promise for enhancing diagnostic precision and therapeutic effectiveness in oncology and neurology, offering a robust pathway for future biomedical advancements. Addressing existing limitations could unlock their full potential in improving patient care and outcomes.

Preparation and characterization of high-methoxyl pectin/glycerides emulsion for pH-responsive, targeting, and sustained release of fat-soluble substances

In this study, a pH-responsive emulsion system was prepared, combining high-methoxyl pectin (HMP) with camellia oil glycerides (CG). The emulsion was characterized as O/W type, with HMP serving as the wall material and CG as the oil phase. The physicochemical properties, pH responsiveness, digestion stability, and encapsulated delivery capabilities of the HMP-CG emulsion were investigated. The emulsion showed an average droplet size of 480.47 ± 76.19 nm, possessing a negative charge and a pronounced core-shell structure. HMP package CG enhanced hydrophilic ability and enabled targeted release within the small intestine through the structural changes of HMP. The presence of HMP and CG increased droplet dispersion and target digestibility of the emulsion system, leading to sustainable small intestine-specific release. Overall, HMP-CG emulsion system, composed of natural materials, exhibited the ability to achieve targeted and controllable release via pH-responsive mechanisms, offering an alternative for developing gel materials incorporating fat-soluble substances.

Bacterial ghosts engineered with lipidated antigens as an adjuvant-free vaccine for Chlamydia abortus

Bacterial ghosts (BGs) provide novel vaccine delivery platforms because of their inherent adjuvant properties and efficient antigen delivery capabilities. However, effective engineering strategies are required to modify them for different antigens. In this study, the Escherichia coli (E. coli) ghost was modified by using a lpp’-ompA chimera, a widely used bacterial surface display vector, with a protective antigen macrophage infectivity potentiator (MIP) of Chlamydia abortus (C. abortus), and its protective effect was evaluated in a mouse model. The MIP fusion protein accumulated at 1.2% of the ghost total protein mass and a significant portion of the protein was modified into lipoproteins upon translocation to the BG surface. Lipidated MIP-modified recombinant E. coli ghosts (rECG-lpp’-MIP) effectively promoted antigen-presenting cells (APCs) uptake of antigens and stimulated APCs activation in vivo and in vitro. Immunization with rECG-lpp’-MIP and no adjuvant induced intense specific humoral responses as well as Th1-biased cellular immune responses, which significantly improved the efficiency of C. abortus infection clearance in mice and reduced pathological damage to the uterus. In summary, this study demonstrates that recombinant E. coli ghosts modified with lipidated antigens could help to develop an effective C. abortus vaccine and aid in the development of a universal adjuvant-free vaccine platform.