Pluronic F-68 and F-127 Based Nanomedicines for Advancing Combination Cancer Therapy

Controlled release of deferiprone using iron-responsive nanoparticles integrated with dissolving microneedle for novel alternative treatments of β-thalassemia major

Iron chelating agents (ICs) such as conventional deferiprone are often ineffective when exposed to normal conditions due to their uncontrolled release when treating iron overload in ß-thalassemia major (ß-TM) due to the effects of blood transfusion. Iron deficiency and gastrointestinal side effects are crucial problems that can occur. Therefore, DFP was prepared as nanoparticles (NPs) coated with an iron-responsive (IR) polymer with an average particle size of 354.70 ± 10 nm to control its release. To facilitate optimal delivery, NP-IR-DFP was integrated into a dissolving microneedle (DMN) fabricated with biodegradable and biocompatible poly(vinylpyrrolidone) and poly(vinyl alcohol) polymers. The results showed that the NP-IR-DMN provided excellent insertion and mechanical strength and dissolved quickly after application. In vitro and ex-vivo studies revealed the more controllable release of NP-IR-DFP after integration with the DMN (NP-IR-DMN) for up to 24 h. Most importantly, the developed formula was hemocompatible and did not irritate the skin or cause tissue damage. Furthermore, the in vivo pharmacokinetics were further investigated for 24 h, which revealed short concentration (Cmax of 0.07 ± 0.03 μg/mL) and t1/2 (3.66 ± 0.76 h) under normal conditions and long-term iron overload-modeling conditions with Cmax (2.90 ± 0.14 μg/mL) and t1/2 (10.13 ± 1.00 h). This approach can extend beyond oral delivery by controlling the release of DFP, which can only be released in conditions of iron overload, and has the potential to prevent iron deficiency and excess, thus increasing the efficacy of DFP in β-TM therapy.

Investigating the interactions between a poloxamer and TEMPO-oxidised cellulose nanocrystals

Cellulose nanocrystals (CNCs) have emerged as promising, sustainable materials, with applications in sensors, coatings, pharmaceuticals, and composites. Their modification with block copolymers such as PEO-PPO-PEO triblock copolymers of the Pluronic family has been attempted many times in the literature, with claims that such modification would happen by an anchor(PEO)-buoy(PPO)-anchor(PEO) mechanism. However, there is much disagreement in the literature on this. We herein physically adsorbed Pluronic F127, a nontoxic triblock copolymer poloxamer, comprising hydrophilic polyethylene oxide (PEO) and hydrophobic polypropylene oxide (PPO) blocks, onto the surface of TEMPO oxidised CNCs by simple mixing in an aqueous medium. The adsorption of F127 onto the surface of these CNCs was successful and persistent even after solubilisation. The thermal stability of modified TOCNCs increased (by ∼19 °C) compared to their neat and oxidised counterparts. F127-TOCNC suspensions exhibited comparable viscosity to their neat and oxidised counterparts without premature gelation of F127. NOESY NMR observations showed that PPO blocks are more proximal to the TOCNC than the PEO blocks. AFM and QCM-D analyses supported the formation of a rigid, thin layer of block copolymer surrounding the TOCNC. A degree of modification (7 %) was achieved, even after washing, proving that adsorption is persistent and mainly irreversible.

Construction of Chitosan Oligosaccharide-Coated Nanostructured Lipid Carriers for the Sustained Release of Strontium Ranelate

BACKGROUND

Strontium ranelate (SR) is an effective bone regeneration drug; however, its low bioavailability and strong hydrophilicity cause a strong cytotoxicity, venous thrombosis, and allergic reactions when administered in its free form. This study aims to enhance the SR bioavailability by utilizing nanostructured lipid carriers (NLC) as a drug delivery system (DDS).

METHODS

To improve the drug delivery efficiency and sustained release of the NLC, their surfaces were coated with chitosan oligosaccharide (COS), a natural polymer. The synthesis of COS-NLC was confirmed by measuring particle size and zeta potential, while surface morphology was evaluated using atomic force microscopy (AFM). SR loading efficiencies and release profiles were analyzed via reversed-phase high-performance liquid chromatography (RP-HPLC), and cytotoxicity was evaluated in mouse fibroblast L929 cells.

RESULTS

Particle characterization indicated that the COS coating slightly increased the particle size (i.e., from 128.99 ± 2.77 to 131.46 ± 2.13 nm) and zeta potential (i.e., from - 13.94 ± 0.49 to - 6.58 ± 0.32 mV) of the NLC. The COS-NLC exhibited a high SR-loading efficiency of ~ 86.31 ± 3.28%. An in vitro release test demonstrated an improved sustained release tendency of SR from the COS-NLC compared to that from the uncoated NLC. In cytotoxicity assays using L929 cells, the COS coating reduced the cytotoxicity of the formulated DDS, and the SR-COS-NLC exhibited a 1.4-fold higher cell regeneration effect than SR alone.

CONCLUSION

These findings suggest that the developed COS-NLC serve as an effective and biocompatible DDS platform for the delivery of poorly bioavailable drugs.

Nanoencapsulation of ascorbic acid loaded in pluronic® F127 coated by chitosan-alginate polyelectrolyte complex and application of a direct quantification method to enhance its accuracy

Ascorbic acid (AA) is an active ingredient in numerous food, pharmaceutical, and cosmetic products. Due to its high instability and reactivity, encapsulation is a strategy to enhance its bioavailability. However, encapsulating AA is challenging, and assessing its encapsulation efficiency (EE) also poses difficulties because the indirect method typically used is inappropriate for AA, as it does not consider AA's degradation kinetics. The composite nanoparticles (NPs) were prepared by using three biocompatible polymers - pluronic® F127 (PLX), alginate (ALG), and chitosan (CS). PLX micelles loaded with six distinct AA amounts (1 to 20 mg) were coated by CS-ALG polyelectrolyte complex (PEC). SEM images indicated that NPs have an almost spherical shape, while TEM images confirm the presence of PLX micelles within the NPs. The average particle size ranged from 291 to 399 nm, with a Zeta potential exceeding 34 mV and a polydispersity index of <0.32 for AA-loaded NPs formulations. Regarding the inconsistencies in AA quantification, we applied a colorimetric method for quantifying AA directly in the NPs and for accurately quantifying AA in release studies (pH 5.5 and 7.4). CS-ALG PEC NPs showed suitable properties for short-term topical treatments, delivering AA at a constant rate over time.

KRASG12D-driven pentose phosphate pathway remodeling imparts a targetable vulnerability synergizing with MRTX1133 for durable remissions in PDAC

The KRASG12D inhibitor MRTX1133 shows the potential to revolutionize the treatment paradigm for pancreatic ductal adenocarcinoma (PDAC), yet presents challenges. Our findings indicate that KRASG12D remodels a pentose phosphate pathway (PPP)-dominant central carbon metabolism pattern, facilitating malignant progression and resistance to MRTX1133 in PDAC. Mechanistically, KRASG12D drives excessive degradation of p53 and glucose-6-phosphate dehydrogenase (G6PD)-mediated PPP reprogramming through retinoblastoma (Rb)/E2F1/p53 axis-regulated feedback loops that amplify ubiquitin-conjugating enzyme E2T (UBE2T) transcription. Genetic ablation or pharmacological inhibition of UBE2T significantly suppresses PDAC progression and potentiates MRTX1133 efficacy. Leveraging structure advantages of the UBE2T inhibitor pentagalloylglucose (PGG), we develop a self-assembling nano co-delivery system with F-127, PGG, and MRTX1133. This system enhances the efficacy of PGG and MRTX1133, achieving durable remissions (85% overall response rate) and long-term survival (100% progression-free survival) in patient-derived xenografts and spontaneous PDAC mice. This study reveals the role of KRASG12D-preferred PPP reprogramming in MRTX1133 resistance and proposes a potentially therapeutic strategy for KRASG12D-mutated PDAC.

Recent applications of stimulus-responsive smart hydrogels for osteoarthritis therapy

Osteoarthritis is one of the most common degenerative joint diseases, which seriously affects the life of middle-aged and elderly people. Traditional treatments such as surgical treatment and systemic medication, often do not achieve the expected or optimal results, which leads to severe trauma and a variety of side effects. Therefore, there is an urgent need to develop novel therapeutic options to overcome these problems. Hydrogels are widely used in biomedical tissue repairing as a platform for loading drugs, proteins and stem cells. In recent years, smart-responsive hydrogels have achieved excellent results as novel drug delivery systems in the treatment of osteoarthritis. This review focuses on the recent advances of endogenous stimuli (including enzymes, pH, reactive oxygen species and temperature, etc.) responsive hydrogels and exogenous stimuli (including light, shear, ultrasound and magnetism, etc.) responsive hydrogels in osteoarthritis treatment. Finally, the current limitations of application and future prospects of smart responsive hydrogels are summarized.

Microbial astaxanthin-encapsulated polymeric micelles from yeast Phaffia rhodozyma for personalized bioactive colored natural rubber latex bandages

This study explores the development of bioactive, colored natural rubber latex (NRL) bandages by incorporating astaxanthin (AXT), a carotenoid with potent antioxidant and anti-inflammatory properties. AXT is produced by the yeast Phaffia rhodozyma under various light conditions to improve AXT biosynthesis and encapsulated in polymeric micelles to enhance its solubility and stability. The encapsulated AXT is then integrated into NRL bandages, imparting a orange-red hue and potentially therapeutic benefits. Physicochemical characterizations, including UV-Vis spectroscopy and FTIR, reveal interactions between AXT and the micelle components. The bandages exhibit improved hydrophilicity and maintain their thermal stability post-AXT incorporation. Antioxidant capacity assessments show that the NRL bandages retain a significant portion of AXT's antioxidant properties, which can aid in wound healing. The release profile of AXT from the bandages demonstrates an initial burst followed by sustained release, indicating effective delivery of the carotenoid. This innovative approach combines aesthetic appeal with biomedical advantages, offering a personalized solution for wound care applications.

Development of Pluronic-Based Micelles from Palm Oil Bioactive Compounds Incorporated by a Dissolvable Microarray Patch to Enhance the Efficacy of Atopic Dermatitis Therapy

The high content of vitamin E, including tocopherols and tocotrienols (TCF-TTE), in palm oil (Elaeis guineensis) has made it a promising candidate for the alternative treatment of atopic dermatitis (AD). However, the limited solubility of TCF-TTE has restricted its therapeutic efficacy. In this study, pluronic-based micelles (MCs) encapsulating palm oil-derived TCF-TTE were formulated with dissolvable microarray patch-micelles (DMP-MC) using carboxymethyl cellulose (CMC) synthesized from empty fruit bunches of palm to optimize its delivery for AD. The MC was prepared using a direct dissolution method using Pluronic F68 and F127. The results showed that MC increased the solubility of TCF-TTE, which was further confirmed by an in vitro study where 90.23 ± 2.07% TCF and 4.56 ± 1.36% TTE were released compared to the unencapsulated TCF-TTE extract. Furthermore, CMC biopolymers and MC integrated into DMP-MC with polyvinylpyrrolidone (PVP) exhibited favorable physical properties, such as mechanical strength and penetration ability. DMP-MC also exhibited a better platform with lower permeation, indicating higher retention and increased localized effects on AD skin than cream-MC. Additionally, dermatokinetic profile parameters showed significant improvement. The mean residence time (MRT) parameter indicated that TCF-TTE was retained for longer times 19.28 ± 0.02 h and 20.68 ± 0.01 h. Moreover, an in vivo study revealed that DMP-MC could relieve AD symptoms more rapidly than oral doses and cream-MC, indicating that DMP-MC proved to be more efficient. Furthermore, DMP-MC showed no tissue destruction (granulation and fibrosis) in rats treated with DMP-MC on the seventh day. Therefore, this study successfully developed the MC formula in DMP-MC formulation using synthesized CMC, which could potentially improve AD's therapeutic efficacy.

Balancing sterilization and functional properties in Poloxamer 407 hydrogels: comparing heat and radiation techniques

Poloxamer 407, also known as Pluronic® F127, is gaining interest in the cosmetic, biomedical and pharmaceutical fields for its biocompatibility, safety and thermo-sensitive properties. Ensuring sterility is critical in clinical applications, and sterilization is often preferred over aseptic processing. However, sterilization can impact the functional properties of the hydrogel. In this study, we investigate the effects of steam heat (121°C, 20 min), dry heat (160°C, 1 h), gamma irradiation (25 kGy) and electron beam (e-beam) irradiation (15 and 25 kGy) on a 30% w/v Poloxamer 407 hydrogel formulation. Our analysis encompasses gelling properties, pH, Fourier-transform infrared spectroscopy, gel permeation chromatography, small-angle X-ray scattering, rheology, swelling, degradation by-products and lactate dehydrogenase release of the sterilized hydrogels, comparing them to a non-sterile counterpart. We demonstrated that heat sterilization alters the hydrogel's gelling and structural properties due to water evaporation and oxidation under harsh temperature conditions, especially when applying the dry heat method. Gamma irradiation proved unsuitable, resulting in an acidic and cytotoxic hydrogel due to oxidative degradation. In contrast, e-beam irradiation preserves the hydrogel's elasticity, gelling and structural properties while enhancing mechanical resilience and moderating swelling. Therefore, e-beam irradiation within the 15-25 kGy range appears to be the most suitable method for sterilizing a 30% w/v Poloxamer 407 hydrogel.

An analytical review of the therapeutic application of recent trends in MIL-based delivery systems in cancer therapy

MILs (Materials Institute Lavoisier), as nanocarriers based on metal-organic frameworks (MOFs), are one of the most advanced drug delivery vehicles that are now a major part of cancer treatment research. This review article highlights the key features and components of MIL nanocarriers for the development and improvement of these nanocarriers for drug delivery. Surface coatings are one of the key components of MIL nanocarriers, which play the role of stabilizing the nanocarrier, pH-dependent drug release, increasing the half-life of the drug, and targeting the carrier. MIL nanocarriers have been synthesized mainly by thermal and hydrothermal methods due to their single-step nature and the ability to produce individual crystals with tunable sizes. According to the data available in the literature, MIL-53 and MIL-101 are the best MILs for drug delivery. These MILs have a high ability to release drugs under acidic conditions, indicating their high efficiency compared to other MILs. In addition to drugs, these nanocarriers can also carry fluorescent, photothermal, and photodynamic agents. These agents allow the MIL nanocarriers to benefit from the therapeutic potential of photothermal and photodynamic agents in addition to the therapeutic capacity of the drug. Furthermore, the fluorescent active ingredient gives these nanocarriers a further tracking capability in addition to the inherent tracking capability of MRI. Therefore, MIL nanocarriers as theranostic carriers have the potential to revolutionize both drug delivery and imaging.

Peptide-Based Prodrug Approaches for Cancer Nanomedicine

Peptide-based prodrugs, such as peptide-drug conjugates (PDCs), are currently being developed for cancer therapy. PDCs are considered single-component nanomedicines with various functionalities. The peptide moieties provide stability to the PDCs, which self-assemble into nanostructures in an aqueous medium. Several PDCs based on peptide moieties have been developed for targeted cancer therapy, prevention of multidrug resistance (MDR), and theranostic applications. Based on this information, next-level strategies have been developed to deliver therapeutics and diagnostics to tumor tissues. The induction of apoptosis-targeted therapy is a conceptual approach that has evolved. In this context, smart PDCs have been designed and explored to overcome tumor heterogeneity. This review highlights strategies for the targeted delivery of small molecules and theranostic applications. Moreover, a conceptual approach to induce apoptosis-targeted therapy was exploited through the delivery of smart PDC nanomedicines and their composites.

Folic Acid-Targeted Mixed Pluronic Micelles for Delivery of Triptolide

The present study aimed to explore an ideal delivery system for triptolide (TPL) by utilizing the thin-film hydration method to prepare drug-loaded, folate-modified mixed pluronic micelles (FA-F-127/F-68-TPL). Scanning electron microscopy and atomic force microscopy showed that the drug-loaded micelles had a spherical shape with a small particle size, with an average of 30.7 nm. Cell viability experiments showed that FA-F-127/F-68-TPL significantly reduced HepG2 cell viability, exhibiting strong cytotoxicity. Its cytotoxicity was markedly enhanced compared with bare TPL. Nile red (Nr) was used as a model drug to prepare FA-F-127/F-68-Nr to further validate its tumor-targeting and cellular uptake capability. After coincubation with HepG2 cells, a multifunctional microplate reader showed that intracellular fluorescence intensity significantly increased, indicating that FA-F-127/F-68-Nr could more effectively enter the cells. A nude mouse model of subcutaneous hepatocellular carcinoma was constructed. Following tail vein injection of FA-F-127/F-68-Nr, the fluorescence imaging system showed that FA-F127/F-68-Nr could significantly target tumor tissue, and even if entering the small-sized tumor was challenging, it could be excreted through urine. Nude mice with subcutaneous hepatocellular carcinoma were treated with tail vein injections of FA-F-127/F-68-TPL (45 µg/kg) every other day for 21 days. The results showed that the growth of the transplanted tumors was significantly slowed, with no significant difference compared with bare TPL. In summary, the FA-F-127/F-68-TPL exhibits the advantages of low cost, excellent biological properties, active/passive targeting capabilities, notable cytotoxicity against liver cancer cells, and significant inhibition of transplanted hepatocellular carcinoma growth. Significantly, the FA-F-127/F-68-TPL, despite challenges in targeting tumors with an insignificant EPR effect, can be efficiently excreted via the kidneys, thereby preventing the release of the drug during prolonged circulation and potential damage to normal tissues. Therefore, FA-F-127/F-68-TPL represents a promising antitumor drug delivery system.

Multi-physics numerical simulation study on thermo-sensitive gel delivery for a local post-tumor surgery treatment

Numerous studies in the literature have proposed the use of thermo-responsive hydrogels for filling cavities after tumor resection. However, optimizing the injection process is challenging due to the complex interplay of various multi-physics phenomena, such as the coupling of flow and heat transfer, multi-phase interactions, and phase-change dynamics. Therefore, gaining a fundamental understanding of these processes is crucial. In this study, we introduce a thermo-sensitive hydrogel formulated with poloxamer 407 and Gellan gum as a promising filling agent, offering an ideal phase-transition temperature along with suitable elastic and viscous modulus properties. We performed multi-physics simulations to predict the flow and temperature distributions during hydrogel injection. The results suggested that the hydrogel should be kept at 4 °C and injected within 90 s to avoid reaching the transition temperature. Cavity filling simulations indicated a symmetric distribution of the hydrogel, with minimal influence from the syringe's position. The temperature gradient at the cavity edge delays gelation during injection, which is essential to guarantee its administration as a liquid. The hydrogel's viscosity follows a sigmoidal function relative to temperature, taking five minutes to reach its maximum value. In summary, the multi-physics simulations carried out in this study confirm the potential of thermo-responsive hydrogels for use in post-tumor surgery treatment and define the conditions for a proper administration. Furthermore, the proposed model can be widely applied to other thermo-responsive hydrogels or under different conditions.

Temperature Sensitive Pluronic F127‐Based Gels Incorporating Natural Therapeutic Agents

Pluronic F127 copolymer is used as the main component to design injectable gels for therapeutic applications. Xanthan gum is added as an excipient to improve gel properties under physiological conditions. A polyphenol bioactive compound, curcumin, is selected as therapeutic agent with beneficial effects on metabolism and many diseases. The encapsulation efficiency and stability of formulations are investigated in an aqueous environment and in acetic acid solutions. The interactions between the hydrophobic polyphenol and the polymer matrix are investigated through rheology, DLS, and FTIR spectroscopy. The viscoelasticity of gels, correlated with the network structure, is influenced by xanthan gum or acetic acid addition. FTIR analysis of curcumin incorporated into the gel provides the evidence for interaction of the phenyl rings of both keto‐enol and di‐keto tautomers with the polymeric matrix. The spherical curcumin‐encapsulated micelles provided antioxidant properties. The kinetics of curcumin release from the Pluronic F127‐based gels suggests anomalous transport phenomena controlled by diffusion through the network and hydrodynamic effects. Both gel and lyophilized form of micellar encapsulated curcumin composites exhibited good stability for long‐term storage under ambient conditions.

Cord Blood Platelet Lysate-Loaded Thermo-Sensitive Hydrogels for Potential Treatment of Chronic Skin Wounds

BACKGROUND/OBJECTIVES

Chronic skin wounds (CSWs) are a worldwide healthcare problem with relevant impacts on both patients and healthcare systems. In this context, innovative treatments are needed to improve tissue repair and patient recovery and quality of life. Cord blood platelet lysate (CB-PL) holds great promise in CSW treatment thanks to its high growth factors and signal molecule content. In this work, thermo-sensitive hydrogels based on an amphiphilic poly(ether urethane) (PEU) were developed as CB-PL carriers for CSW treatment.

METHODS

A Poloxamer 407®-based PEU was solubilized in aqueous medium (10 and 15% w/v) and added with CB-PL at a final concentration of 20% v/v. Hydrogels were characterized for their gelation potential, rheological properties, and swelling/dissolution behavior in a watery environment. CB-PL release was also tested, and the bioactivity of released CB-PL was evaluated through cell viability, proliferation, and migration assays.

RESULTS

PEU aqueous solutions with concentrations in the range 10-15% w/v exhibited quick (within a few minutes) sol-to-gel transition at around 30-37 °C and rheological properties modulated by the PEU concentration. Moreover, CB-PL loading within the gels did not affect the overall gel properties. Stability in aqueous media was dependent on the PEU concentration, and payload release was completed between 7 and 14 days depending on the polymer content. The CB-PL-loaded hydrogels also showed biocompatibility and released CB-PL induced keratinocyte migration and proliferation, with scratch wound recovery similar to the positive control (i.e., CB-PL alone).

CONCLUSIONS

The developed hydrogels represent promising tools for CSW treatment, with tunable gelation properties and residence time and the ability to encapsulate and deliver active biomolecules with sustained and controlled kinetics.

Impact of Pluronic F-127 on the Stability of Quercetin-Loaded Liposomes: Insights from DSC Preformulation Studies

The aim of the present study is to evaluate the stability of DMPC:Pluronic F-127 and DPPC:Pluronic F-127 liposomes, both with and without incorporated quercetin. Quercetin belongs to the class of flavonoids and has shown antioxidant, antiviral, anti-inflammatory, anti-cancer, and antimicrobial activities. Dynamic light scattering, electrophoretic light scattering, and differential scanning calorimetry (DSC) were utilized to investigate the cooperative behavior between liposomal components and its effect on stability. All formulations were stored at 4 °C and 25 °C and studied over 42 days. Furthermore, the interaction of the final formulations with serum proteins was assessed to evaluate the potential of Pluronic F-127 as a stabilizer in these liposomal nanosystems. This study highlights the impact of DSC in preformulation evaluations by correlating thermal behavior with quercetin incorporation and variations in size and the polydispersity index. According to the results, quercetin increased the fluidity and stability of liposomal nanosystems, while Pluronic F-127 was not sufficient for effective steric stabilization. Additionally, DSC thermograms revealed the integration of Pluronic F-127 into lipid membranes and showed phase separation in the DMPC nanosystem. In conclusion, the results indicate that the DPPC:Pluronic F-127:quercetin nanosystem exhibited the desired physicochemical and thermotropic properties for the effective delivery of quercetin for pharmaceutical purposes.

Hyaluronic acid methacrylate/Pluronic F127 hydrogel enhanced with spermidine-modified mesoporous polydopamine nanoparticles for efficient synergistic periodontitis treatment

Bacterial infection, reactive oxygen species (ROS) accumulation, and persistent inflammation pose significant challenges in the treatment of periodontitis. However, the current single-modal strategy makes achieving the best treatment effect difficult. Herein, we developed a double-network hydrogel composed of Pluronic F127 (PF-127) and hyaluronic acid methacrylate (HAMA) loaded with spermidine-modified mesoporous polydopamine nanoparticles (M@S NPs). The PF-127/HAMA/M@S (PH/M@S) hydrogel was injectable and exhibited thermosensitivity and photocrosslinking capabilities, which enable it to adapt to the irregular shape of periodontal pockets. In vitro, the PH/M@S displayed multiple therapeutic effects, such as photothermal antibacterial activity, a high ROS scavenging capacity, and anti-inflammatory effects, which are beneficial for the multimodal treatment of periodontitis. The underlying anti-inflammatory mechanism of this hydrogel involves suppression of the extracellular regulated protein kinase 1/2 and nuclear factor kappa-B signalling pathways. Furthermore, in lipopolysaccharide-stimulated macrophage conditioned media, the PH/M@S effectively restored the osteogenic differentiation potential. In a rat model of periodontitis, the PH/M@S effectively reduced the bacterial load, relieved local inflammation and inhibited alveolar bone resorption. Collectively, these findings highlight the versatile functions of the PH/M@S, including photothermal antibacterial activity, ROS scavenging, and anti-inflammatory effects, indicating that this hydrogel is a promising multifunctional filling material for the treatment of periodontitis.

Tumor cell loaded thermosensitive hydrogel for photodynamic therapy associated tumor antigens release

BACKGROUND

Immunotherapy is a powerful strategy for treating cancer and can be used to inhibit the post-surgical relapse of tumors.

METHODS

To achieve this, a Cell@hydrogel was developed as a template using a mixture of CT26 tumor cells and Pluronic® F-127/gelatin.

RESULTS

The proposed mixture has a solution-to-gelation functionality and vice versa. The morphology of the Cell@hydrogel was characterized by scanning electron microscopy and confocal microscopy. For photodynamic immunotherapy, the Cell@hydrogel was functionalized with Cy7 (Cy7-Cell@hydrogel) to quantify reactive oxygen species in CT26 tumor cells. Gel electrophoresis and membrane integrity tests were performed to determine the efficiency of the Cy7-Cell@hydrogel following photodynamic therapy.

CONCLUSIONS

This protocol provides an alternative approach that mechanistically inhibits the post-surgical relapse of solid tumors based on immunotherapy.

Self-assembly of Pluronics: A critical review and relevant applications

Pluronics, alias poloxamers, are synthetic amphiphilic copolymers owning a triblock structure with a central hydrophobic poly(propylene oxide) (PPO) segment linked to two lateral hydrophilic poly(ethylene oxide) (PEO) chains. Commercially, Pluronics exist in numerous types according to the length of PPO and PEO chains, exhibiting different behavior and phase diagrams in solution. Concentrated aqueous solutions of Pluronics form thermoreversible gel-like systems. Properties, such as versatility, biocompatibility, nontoxicity, thermosensitivity and self-assembling behavior, make them extremely attractive for numerous applications. This review paper provides an overview on Pluronics, with a focus on their properties and phase behaviors, and on the effect of the presence of salts and additives. Different strategies to endow Pluronics with improved and extra properties, such as their chemical modification and mixed micelles, are briefly illustrated. Furthermore, a synopsis of useful experimental methodologies for understanding the flow properties of Pluronic-based systems is presented, providing a practical guide to their experimental characterization. Eventually, significant advances of Pluronic-based materials are briefly reviewed to elucidate their role in diverse applications, ranging from drug delivery and tissue engineering to bioprinting, cell cultures, personal care industry, conductive hydrogels, and electrocatalytic science. The current article is a critical review of Pluronic block copolymers, not intended as just inert materials but also as systems with functional properties able to revolutionize the paradigm of many technological fields.

Synthesis of F127-GA@ZnO nanogel as a cisplatin drug delivery pH-sensitive system

In this study, a novel drug delivery system based on zinc oxide nanoparticles (ZnO NPs) was developed for the enhanced delivery of cisplatin (CPT) to improve cancer treatment. The ZnO NPs were synthesized from guava leaf extract and then surface-functionalized with gallic acid (GA) to improve their biocompatibility and drug loading capacity. Pluronic F127, a biocompatible polymer, was then conjugated to the GA-modified ZnO NPs to further enhance their stability and cellular uptake. The resulting NPs were characterized by various techniques, including FT-IR, UV-Vis, SEM, TEM, 1H NMR, and DLS. The drug loading and release profiles of CPT from the NPs were investigated, showing high CPT loading capacity and pH-dependent release behavior. The in vitro cytotoxicity of the NPs was evaluated against various cancer cell lines, demonstrating enhanced cytotoxicity compared to free CPT. Overall, this study highlights the potential of GA and Pluronic-modified ZnO NPs as a promising drug delivery system for enhanced CPT delivery and improved cancer therapy.

Inhibition of Food Spoilage Fungi, Botrytis cinerea and Rhizopus sp., by Nanoparticles Loaded with Baccharis dracunculifolia Essential Oil and Nerolidol

This study investigates the antifungal potential of encapsulated essential oil (EO) from Baccharis dracunculifolia and nerolidol (NE) within Pluronic® F-127 nanoparticles (NPs). The EO, containing nerolidol, β-caryophyllene, and α-pinene as major bioactive compounds, exhibited superior antifungal activity compared to NE. The NP-EO formulations demonstrated high efficacy against Botrytis cinerea, with inhibition rates ranging from 29.73% to 87.60% and moderate efficacy against Rhizopus sp., with inhibition rates from 11.81% to 32.73%. In comparison, NP-NE showed lower antifungal activity. Both formulations effectively inhibited spore germination, with NP-EO showing greater inhibition compared to NP-NE. The encapsulation efficiency was significantly higher for NP-EO (80.1%) as compared to NP-NE (51.1%), attributed to the complex composition of EO facilitating better encapsulation and retention. Stability studies indicated that both NP formulations were stable at 25 °C for at least 15 days and exhibited changes in particle size and the formation of smaller particle populations at other temperatures (4 °C and 37 °C). Hemolytic activity was low across all NPs, suggesting their safety for food applications. The findings underscore the efficacy and applicability of EO-encapsulated NPs in extending food shelf life and maintaining product quality. The controlled and prolonged release of active compounds, coupled with their antifungal activity and safety, suggests that these NPs represent a promising and innovative approach for food preservation and active packaging development.

Formulation of Thermo-Sensitive In Situ Gels Loaded with Dual Spectrum Antibiotics of Azithromycin and Ofloxacin

In situ gels have been developed as an innovative strategy to prolong corneal residence time and enhance drug absorption compared to traditional eye drops. Our study aimed to formulate an ophthalmic in situ gel with a combination of two thermosensitive poloxamers, P407 and P188, in an optimal ratio not only to increase the time of action but also to increase the solubility of selected antibiotics for the treatment of ophthalmic infections. Two BSC II class substances, Azithromycin and Ofloxacin, with different mechanisms of action, have been incorporated into the in situ gel system after determining their solubility. The antibiotics-loaded in situ gel formulation was evaluated for its clarity, pH, rheological properties, and gel characteristics of gelling time, temperature, and capacity. The formulation demonstrated satisfactory clarity, appropriate pH, effective gelation properties in simulated tear fluid, and suitable rheological characteristics. In addition, APIs release insight has been studied through a dissolution test, and the effectivity against sensitive and resistant bacterial strains has been proved through the antimicrobial study. Therefore, our in situ gel system based on thermosensitive poloxamers, with two hydrophobic antibiotics, AZM and OFX, can be considered a valuable approach for ophthalmic drug delivery with an enhancement of the antibiotics bioavailability through increasing the contact time with the ocular surface and enhancing patient compliance.

Development of Transdermal Formulation Integrating Polymer-Based Solid Microneedles and Thermoresponsive Gel Fucoidan for Antiaging: Proof of Concept Study

Skin can be damaged by intense and prolonged exposure to ultraviolet (UV) radiation. Photoaging and acute damage from sun exposure result in collagen degradation and enzymatic activity decline in the skin. Fucoidan (FUC) exhibits potential antiaging properties, including collagen synthesis promotion and enzyme activity inhibition. However, FUC's limited ability to penetrate the skin layers due to its large molecular weight makes it a challenge for topical application. In this study, we successfully developed a new approach by integrating thermoresponsive gel (TRG) containing FUC with solid microneedles (SMNs) as a delivery system. TRG is formulated using a combination of Pluronic F127 (PF127) and Pluronic F68 (PF68) polymers, while SMNs are made from a mixture of poly(vinyl alcohol) (PVA) and poly(vinylpyrrolidone) (PVP) polymers with a variety of cross-linkers. Based on the results of ex vivo testing, it was shown that more than 80% of FUC can be delivered using the optimized formula. Furthermore, the results of the in vitro blood hemolytic test showed that TRG-FUC-SMNs were relatively biocompatible. In vivo antiaging activity tests using a rat model exposed to UV for 14 days showed that histological assessment, skin elasticity measurement, wrinkle evaluation, and skin moisture content had no significant differences (p < 0.05) compared to the positive control group. In contrast, a significant difference (p < 0.05) was observed when comparing the TRG-FUC-SMNs group with the group that received only TRG-FUC without pretreatment and negative controls. These findings suggest that FUC has potential to be delivered using the TRG system in combination with SMNs to harness its antiaging properties.

Liposomal Drug Delivery against Helicobacter pylori Using Furazolidone and N-Acetyl Cysteine in Augmented Therapy

Helicobacter pylori (H. pylori) infection is a significant global health concern, affecting approximately 50% of the world's population and leading to gastric ulcers, gastritis, and gastric cancer. The increase in antibiotic resistance has compromised the efficacy of existing therapeutic regimens, necessitating novel approaches for effective eradication. This study aimed to develop a targeted liposomal drug delivery system incorporating furazolidone and N-acetylcysteine (NAC) to enhance mucopenetration and improve Helicobacter pylori eradication. Liposomes were formulated with furazolidone, NAC, and Pluronic F-127 using a modified reverse-phase evaporation technique. The formulations were categorized based on charge as neutral, negative, and positive and tested for mucopenetration using a modified silicon tube method with coumarin-6 as a fluorescent marker. The encapsulation efficiency and particle size were analyzed using HPLC and an Izon q-nano particle size analyzer. The results indicated that charged liposomes showed a higher encapsulation efficiency than neutral liposomes with Pluronic F-127. Notably, combining furazolidone with 1% NAC achieved complete eradication of H. pylori in 2.5 h, compared to six hours without NAC. The findings of this study suggest that incorporating NAC and Pluronic F-127 into liposomal formulations significantly enhances mucopenetration and antimicrobial efficacy.

Fisetin-loaded pluronic-based nanogel: Radiation synthesis for alleviating neurocognitive impairments in a rat model of alzheimer's disease via modulation of the apoptotic cascade

Alzheimer's disease (AD) is a neurodegenerative disorder marked by cognitive impairment and memory loss. In this study, AD was experimentally induced in rats using aluminum chloride (AlCl3) and D-galactose (D-gal). Fisetin (Fis), a natural compound with antioxidant and anti-inflammatory properties, has potential for neurodegeneration management, but its low bioavailability limits clinical applications. To address this, we synthesized and characterized Pluronic-2-Acrylamido-2-methylpropane sulfonic acid (PLUR-PAMPS) nanogels using gamma radiation and successfully loaded Fis onto them (Fis-PLUR-PAMPS). The optimal formulation exhibited minimal particle size, a highly acceptable polydispersity index, and the highest zeta-potential, enhancing stability and solubilization efficiency. Our goal was to improve Fis's bioavailability and assess its efficacy against AlCl3/D-gal-induced AD. Male albino Wistar rats were pre-treated orally with Fis (40 mg/kg) or Fis-PLUR-PAMPS for seven days, followed by a seven-day intraperitoneal injection of AlCl3 and D-gal. Behavioral assessments, histopathological analysis, and biochemical evaluation of markers related to AD pathology were conducted. Results demonstrated that Fis-PLUR-PAMPS effectively mitigated cognitive impairments and neurodegenerative signs induced by AlCl3/D-gal. These findings suggest that Fis-PLUR-PAMPS nanogels enhance Fis's bioavailability and therapeutic efficacy, offering a promising approach for AD management.

Protein-free media for cardiac differentiation of hPSCs in 2000 mL suspension culture

BACKGROUND

Commonly used media for the differentiation of human pluripotent stem cells into cardiomyocytes (hPSC-CMs) contain high concentrations of proteins, in particular albumin, which is prone to quality variations and presents a substantial cost factor, hampering the clinical translation of in vitro-generated cardiomyocytes for heart repair. To overcome these limitations, we have developed chemically defined, entirely protein-free media based on RPMI, supplemented with L-ascorbic acid 2-phosphate (AA-2P) and either the non-ionic surfactant Pluronic F-68 or a specific polyvinyl alcohol (PVA).

METHODS AND RESULTS

Both media compositions enable the efficient, directed differentiation of embryonic and induced hPSCs, matching the cell yields and cardiomyocyte purity ranging from 85 to 99% achieved with the widely used protein-based CDM3 medium. The protein-free differentiation approach was readily up-scaled to a 2000 mL process scale in a fully controlled stirred tank bioreactor in suspension culture, producing > 1.3 × 109 cardiomyocytes in a single process run. Transcriptome analysis, flow cytometry, electrophysiology, and contractile force measurements revealed that the mass-produced cardiomyocytes differentiated in protein-free medium exhibit the expected ventricular-like properties equivalent to the well-established characteristics of CDM3-control cells.

CONCLUSIONS

This study promotes the robustness and upscaling of the cardiomyogenic differentiation process, substantially reduces media costs, and provides an important step toward the clinical translation of hPSC-CMs for heart regeneration.

Novel Ultrasound-Responsive Amyloid Formulation

Amyloid aggregates have attracted significant interest in regard to diverse biomedical applications, particularly in the field of drug delivery. Here, we report novel amyloid aggregates based on a 12-amino-acid peptide from the amyloidogenic region of the receptor-interacting kinase 3 (RIP3) protein and a thermoresponsive triblock copolymer, namely, Pluronic F127 (RIP3/F127). Physicochemical characterization was performed to determine the aggregation size, morphology, and stimuli-responsive properties. The potential of the aggregates as a drug depot was assessed in lung cancer cells, using Doxorubicin (Dox) as a model drug. The results show that RIP3 and RIP3/F127 exhibit amyloidogenic properties. Further, the RIP3/F127 amyloids exhibited significant ultrasound-responsive properties compared to amyloid aggregates without Pluronic F127. Moreover, the RIP3/F127/Dox amyloid formulations that were subjected to ultrasound treatment exhibited greater toxicity to lung cancer cells compared to that of Dox alone at equal concentrations. Overall, the results from this proof-of-concept study show that amyloidogenic peptide aggregates with stimuli-responsive properties can be utilized as efficient drug delivery depots.

Bridging the gap between in vitro and in vivo models: a way forward to clinical translation of mitochondrial transplantation in acute disease states

Mitochondrial transplantation and transfer are being explored as therapeutic options in acute and chronic diseases to restore cellular function in injured tissues. To limit potential immune responses and rejection of donor mitochondria, current clinical applications have focused on delivery of autologous mitochondria. We recently convened a Mitochondrial Transplant Convergent Working Group (CWG), to explore three key issues that limit clinical translation: (1) storage of mitochondria, (2) biomaterials to enhance mitochondrial uptake, and (3) dynamic models to mimic the complex recipient tissue environment. In this review, we present a summary of CWG conclusions related to these three issues and provide an overview of pre-clinical studies aimed at building a more robust toolkit for translational trials.

ECM-mimetic, NSAIDs loaded thermo-responsive, immunomodulatory hydrogel for rheumatoid arthritis treatment

BACKGROUND

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease, and it leads to irreversible inflammation in intra-articular joints. Current treatment approaches for RA include non-steroidal anti-inflammatory drugs (NSAIDs), disease-modifying anti-rheumatic drugs (DMARDs), corticosteroids, and biological agents. To overcome the drug-associated toxicity of conventional therapy and transdermal tissue barrier, an injectable NSAID-loaded hydrogel system was developed and explored its efficacy.

RESULTS

The surface morphology and porosity of the hydrogels indicate that they mimic the natural ECM, which is greatly beneficial for tissue healing. Further, NSAIDs, i.e., diclofenac sodium, were loaded into the hydrogel, and the in vitro drug release pattern was found to be burst release for 24 h and subsequently sustainable release of 50% drug up to 10 days. The DPPH assay revealed that the hydrogels have good radical scavenging activity. The biocompatibility study carried out by MTT assay proved good biocompatibility and anti-inflammatory activity of the hydrogels was carried out by gene expression study in RAW 264.7 cells, which indicate the downregulation of several key inflammatory genes such as COX-2, TNF-α & 18s.

CONCLUSION

In summary, the proposed ECM-mimetic, thermo-sensitive in situ hydrogels may be utilized for intra-articular inflammation modulation and can be beneficial by reducing the frequency of medication and providing optimum lubrication at intra-articular joints.

Phyto-cosmeceutical gel containing curcumin and quercetin loaded mixed micelles for improved anti-oxidant and photoprotective activity

Ultra Violet radiations induced skin damage and associated skin disorders are a widespread concern. The consequences of sun exposure include a plethora of dermal conditions like aging, solar urticaria, albinism and cancer. Sunscreens provide effective protection to skin from these damages. Besides FDA approved physical and chemical UV filters, phytoconstituents with their multi functionalities are emerging as frontrunners in Therapy of skin disorders. Objective of this study was to develop novel phyto-dermal gel (PDG) with dual action of sun protection and antioxidant potential using polymeric mixed micelles (PMMs) are nanocarriers. PMMs of Pluronic F127 and Pluronic F68 loaded with curcumin and quercetin were optimized by 32 factorial designs. Responses studied were vesicle size, SPF, entrapment efficiency of curcumin and quercetin and antioxidant activity. Droplet size ranged from 300 to 500 nm with PDI in between 0.248 and 0.584. Combination of curcumin and quercetin showed enhanced sun protection and antioxidant activity. Pluronics played a significant positive role in various parameters. In present studies vesicle size of factorial batches was found to be between 387 and 527 nm, and SPF was found to be between 18.86 and 28.32. Transmission electron microscopy revealed spherical morphology of micelles. Optimized micelles were incorporated into Carbopol 940. Optimized PDG was evaluated for pH, drug content, spreadability, rheology, syneresis, ex vivo permeation, and skin retention. Hysteresis loop in the rheogram suggested thixotropy of PDG. Syneresis for gels from day 0-30 days was found to be between 0% and 12.46% w/w. SPF of optimized PDG was 27±0.5. Optimized PDG showed no signs of erythema and edema on Wistar rats. PMMs thus effectively enhanced antioxidant and skin protective effect of curcumin and quercetin.

Investigation of morphology and structure of drug-loaded PLA-b-PEO-b-PLA polymeric micelle: A dissipative particle dynamics simulations study

The dissipative particle dynamics (DPD) simulation was used to study the morphologies and structures of the paclitaxel-loaded PLA-b-PEO-b-PLA polymeric micelle. We focused on the influences of PLA block length, PLA-b-PEO-b-PLA copolymer concentration, paclitaxel drug content on morphologies and structures of the micelle. Our simulations show that: (i) with the PLA block length increase, the self-assemble structure of PLA-b-PEO-b-PLA copolymers with paclitaxel vary between onion-like structure (core-middle layer-shell) to spherical core-shell structure. The PEO shell thins and the size of the PLA core increases. The onionlike structures are comprised of the PEO hydrophilic core, the PLA hydrophobic middle layer, and the PEO hydrophilic shell, the distribution of the paclitaxel drug predominantly occurs within the hydrophobic intermediate layer; (ii) The system forms a spherical core-shell structure when a small amount of the drug is added, and within a certain range, the size of the spherical structure increases as the drug amount increases. When the drug contents (volume fraction) cdrug = 10%, it can be observed that the PLA4-b-PEO19-b-PLA4 spherical structures connect to form rod-shaped structures. With the length of PLA block NPLA = 8, as the paclitaxel drug concentrations cdrug = 4%, PEO has been insufficient to completely encapsulate the PLA and paclitaxel drug beads. To enhance drug loading capacity while maintaining stability of the system in aqueous solution, the optimal composition for loading paclitaxel is PLA4-b-PEO19-b-PLA4; the drug content is not higher than 4%; (iii) The paclitaxel-loaded PLA4-b-PEO19-b-PLA4 micelle undergo the transition from onionlike (core-middle layer-shell) to spherical (core-shell) to rod-shaped and lamellar structure as the PLA4-b-PEO19-b-PLA4 copolymer concentration increases from ccp = 10% to 40%.

Surface charge-dependent cytokine production using near-infrared emitting silicon quantum dots

Toll-like receptor 9 (TLR-9) is a protein that helps our immune system identify specific DNA types. Upon detection, CpG oligodeoxynucleotides signal the immune system to generate cytokines, essential proteins that contribute to the body's defence against infectious diseases. Native phosphodiester type B CpG ODNs induce only Interleukin-6 with no effect on interferon-α. We prepared silicon quantum dots containing different surface charges, such as positive, negative, and neutral, using amine, acrylate-modified Plouronic F-127, and Plouronic F-127. Then, class B CpG ODNs are loaded on the surface of the prepared SiQDs. The uptake of ODNs varies based on the surface charge; positively charged SiQDs demonstrate higher adsorption compared to SiQDs with negative and neutral surface charges. The level of cytokine production in peripheral blood mononuclear cells was found to be associated with the surface charge of SiQDs prior to the binding of the CpG ODNs. Significantly higher levels of IL-6 and IFN-α induction were observed compared to neutral and negatively charged SiQDs loaded with CpG ODNs. This observation strongly supports the notion that the surface charge of SiQDs effectively regulates cytokine induction.

Dual ligand-targeted Pluronic P123 polymeric micelles enhance the therapeutic effect of breast cancer with bone metastases

Bone metastasis secondary to breast cancer negatively impacts patient quality of life and survival. The treatment of bone metastases is challenging since many anticancer drugs are not effectively delivered to the bone to exert a therapeutic effect. To improve the treatment efficacy, we developed Pluronic P123 (P123)-based polymeric micelles dually decorated with alendronate (ALN) and cancer-specific phage protein DMPGTVLP (DP-8) for targeted drug delivery to breast cancer bone metastases. Doxorubicin (DOX) was selected as the anticancer drug and was encapsulated into the hydrophobic core of the micelles with a high drug loading capacity (3.44%). The DOX-loaded polymeric micelles were spherical, 123 nm in diameter on average, and exhibited a narrow size distribution. The in vitro experiments demonstrated that a pH decrease from 7.4 to 5.0 markedly accelerated DOX release. The micelles were well internalized by cultured breast cancer cells and the cell death rate of micelle-treated breast cancer cells was increased compared to that of free DOX-treated cells. Rapid binding of the micelles to hydroxyapatite (HA) microparticles indicated their high affinity for bone. P123-ALN/DP-8@DOX inhibited tumor growth and reduced bone resorption in a 3D cancer bone metastasis model. In vivo experiments using a breast cancer bone metastasis nude model demonstrated increased accumulation of the micelles in the tumor region and considerable antitumor activity with no organ-specific histological damage and minimal systemic toxicity. In conclusion, our study provided strong evidence that these pH-sensitive dual ligand-targeted polymeric micelles may be a successful treatment strategy for breast cancer bone metastasis.

Strategies to address key challenges of metallacycle/metallacage-based supramolecular coordination complexes in biomedical applications

Owing to their capacity for dynamically linking two or more functional molecules, supramolecular coordination complexes (SCCs), exemplified by two-dimensional (2D) metallacycles and three-dimensional (3D) metallacages, have gained increasing significance in biomedical applications. However, their inherent hydrophobicity and self-assembly driven by heavy metal ions present common challenges in their applications. These challenges can be overcome by enhancing the aqueous solubility and in vivo circulation stability of SCCs, alongside minimizing their side effects during treatment. Addressing these challenges is crucial for advancing the fundamental research of SCCs and their subsequent clinical translation. In this review, drawing on extensive contemporary research, we offer a thorough and systematic analysis of the strategies employed by SCCs to surmount these prevalent yet pivotal obstacles. Additionally, we explore further potential challenges and prospects for the broader application of SCCs in the biomedical field.

Digital Light Processing 4D Printing of Poloxamer Micelles for Facile Fabrication of Multifunctional Biocompatible Hydrogels as Tailored Wearable Sensors

The lack of both digital light processing (DLP) compatible and biocompatible photopolymers, along with inappropriate material properties required for wearable sensor applications, substantially hinders the employment of DLP 3D printing in the fabrication of multifunctional hydrogels. Herein, we discovered and implemented a photoreactive poloxamer derivative, Pluronic F-127 diacrylate, which overcomes these limitations and is optimized to achieve DLP 3D printed micelle-based hydrogels with high structural complexity, resolution, and precision. In addition, the dehydrated hydrogels exhibit a shape-memory effect and are conformally attached to the geometry of the detection point after rehydration, which implies the 4D printing characteristic of the fabrication process and is beneficial for the storage and application of the device. The excellent cytocompatibility and in vivo biocompatibility further strengthen the potential application of the poloxamer micelle-based hydrogels as a platform for multifunctional wearable systems. After processing them with a lithium chloride (LiCl) solution, multifunctional conductive ionic hydrogels with antifreezing and antiswelling properties along with good transparency and water retention are easily prepared. As capacitive flexible sensors, the DLP 3D printed micelle-based hydrogel devices exhibit excellent sensitivity, cycling stability, and durability in detecting multimodal deformations. Moreover, the DLP 3D printed conductive hydrogels are successfully applied as real-time human motion and tactile sensors with satisfactory sensing performances even in a -20 °C low-temperature environment.

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.

Combating multidrug resistance of breast cancer with ginsenoside Rh2-irrigated nano-in-thermogel

The emergence of multidrug resistance (MDR) is the leading cause of mortality in patients with breast cancer. Overexpressed P-glycoprotein (P-gp) that can pump out chemotherapeutics from multidrug-resistant cancer cells is the main cause of chemotherapy failure. P-gp inhibitors are hence increasingly used to sensitize chemotherapy to breast cancer with MDR by reducing the efflux of drugs. However, representative P-gp inhibitors usually have severe side effects and the effect of their release behavior on chemotherapy are neglected in current studies. We constructed a nano-in-thermogel delivery system with the sequential release of ginsenoside Rh2 (GRh2) and a chemotherapeutic drug in the tumor microenvironment as a drug compounding "reservoir" to combat MDR in breast cancer. Briefly, paclitaxel (PTX) and GRh2 were encapsulated in solid lipid nanoparticles (SLNs) and dispersed in a poloxamer-based thermogel (SLNs-Gel). GRh2 was used as an innovative and safe P-gp inhibitor to lower P-gp expression and cellular adenosine triphosphate context, thereby sensitizing PTX-resistant breast cancer cells (MCF-7/PTX) to PTX. Pharmacodynamic and in vivo safety studies confirmed that intratumoral injection of SLNs-Gel significantly suppressed the proliferation of PTX-resistant breast cancer and alleviated the PTX-induced hematotoxicity. The GRh2-irrigated nano-in-thermogel delivery system shows great potential in combating multidrug-resistant cancer.

Gemcitabine-Vitamin E Prodrug-Loaded Micelles for Pancreatic Cancer Therapy

Pancreatic cancer (PC) is an aggressive cancer subtype presenting unmet clinical challenges. Conventional chemotherapy, which includes antimetabolite gemcitabine (GEM), is seriously undermined by a short half-life, its lack of targeting ability, and systemic toxicity. GEM incorporation in self-assembled nanosystems is still underexplored due to GEM's hydrophilicity which hinders efficient encapsulation. We hypothesized that vitamin E succinate-GEM prodrug (VES-GEM conjugate) combines hydrophobicity and multifunctionalities that can facilitate the development of Pluronic® F68 and Pluronic® F127 micelle-based nanocarriers, improving the therapeutic potential of GEM. Pluronic® F68/VES-GEM and Pluronic® F127/VES-GEM micelles covering a wide range of molar ratios were prepared by solvent evaporation applying different purification methods, and characterized regarding size, charge, polydispersity index, morphology, and encapsulation. Moreover, the effect of sonication and ultrasonication and the influence of a co-surfactant were explored together with drug release, stability, blood compatibility, efficacy against tumour cells, and cell uptake. The VES-GEM conjugate-loaded micelles showed acceptable size and high encapsulation efficiency (>95%) following an excipient reduction rationale. Pluronic® F127/VES-GEM micelles evidenced a superior VES-GEM release profile (cumulative release > 50%, pH = 7.4), stability, cell growth inhibition (<50% cell viability for 100 µM VES-GEM), blood compatibility, and extensive cell internalization, and therefore represent a promising approach to leveraging the efficacy and safety of GEM for PC-targeted therapies.

Study of the effect of active pharmaceutical ingredients of various classes of BCS on the parameters of thermosensitive systems based on poloxamers

Introduction

The development of thermosensitive in situ systems has become widespread and prospective due to the optimal parameters of the phase transition - in the temperature range from room to physiological. Those properties can provide thermosensitive polymers, for example, poloxamers - as the most common.It is worth noting that the addition of active pharmaceutical ingredients (APIs) changes the parameters of in situ systems, but no systematic study of the effect of APIs has been conducted. The aim of this work was to develop a systematic approach to studying the effect of APIs on the in situ rheological properties of poloxamer compositions.

Materials and methods

The biopharmaceutical classification system (BCS) was chosen as the basis. Accordingly, the following APIs were selected for the experiment: BCS class I - lidocaine hydrochloride and ketorolac tromethamine, class II - ibuprofen and diclofenac, class III - pyridoxine hydrochloride and ribavirin, class IV - furosemide and abiraterone. To create thermoreversible compositions, previously studied for stability combinations of poloxamer 407, poloxamer 188 and PEG 1500 were used.At the stage of preparation of experimental samples formulations with APIs of classes II and IV of BCS were excluded, since the solubilizing ability of poloxamers is not enough to obtain stable combined complexes.

Results

In the course of the work, the following results were obtained: BCS class I APIs significantly reduced the phase transition temperature of the matrix of poloxamers 407 and 188, while the addition of PEG 1500 eliminated the effect of APIs on gels; BCS class III APIs practically did not affect the rheological properties of the studied combinations; the phase transition temperature of the gel based on poloxamer 407 did not change with the addition of Class I and Class III APIs.Nevertheless, the obtained results made it possible to reveal the regular behavior of in situ complexes of poloxamer matrices depending on the class of BCS of the API. Further research is required.