Pluronic Research Articles

Microporation-Mediated Transdermal Delivery of In Situ Gel Incorporating Etodolac-Loaded PLGA Nanoparticles for Management of Rheumatoid Arthritis.

Management of rheumatoid arthritis (RA) requires long-term administration of different medications since there has been no cure until now. Etodolac (ETD) is a nonsteroidal anti-inflammatory drug commonly used for RA management. However, its long-term administration resulted in severe side effects. This study aimed to develop a transdermal in situ gel incorporating ETD-loaded polymeric nanoparticles (NPs) to target the affected joints for long-term management of RA. Several PLGA NPs incorporating 1% ETD were prepared by nanoprecipitation and optimized according to the central composite design. The optimum NPs (F1) exhibited 96.19 ± 2.31% EE, 282.3 ± 0.62 nm PS, 0.383 ± 0.04 PDI, and -6.44 ± 1.69 ZP. A hyaluronate coating was applied to F1 (H-F1) to target activated macrophages at inflammation sites. H-F1 exhibited 287.4 ± 4.2 nm PS, 0.267 ± 0.02 PDI, and -23.7 ± 3.77 ZP. Pluronic F-127 in situ gel (H-F1G) showed complete gelation at 29 °C within 5 min. ETD permeation from H-F1G was sustained over 48 h when applied to microporated skin and exhibited significant enhancement of all permeation parameters. Topical application of H-F1G (equivalent to 8 mg ETD) to Wistarrat microporated skin every 48 h resulted in antirheumatic therapeutic efficacy comparable to commercial oral tablets (10 mg/kg/day).

PLGA-LEC/F127 hybrid nanoparticles loaded with curcumin and their modulatory effect on monocytes.

Aim: To investigate the effect of surfactant type on curcumin-loaded (CUR) PLGA nanoparticles (NPs) to modulate monocyte functions. Materials & methods: The nanoprecipitation method was used, and PLGA NPs were designed using PluronicF127 (F127) and/or lecithin (LEC) as surfactants. Results: The Z-average of the NPs was <200nm, they had a spherical shape, Derjaguin-Muller-Toporov modulus >0.128MPa, they were stable during storage at 4°C, ζ-potential ∼-40mV, polydispersity index <0.26 and % EE of CUR >94%. PLGA-LEC/F127NPs showed favorable physicochemical and nanomechanical properties. These NPs were bound and internalized mainly by monocytes, suppressed monocyte-induced reactive oxygen species production,and decreased the ability of monocytes to modulate T-cell proliferation. Conclusion: These results demonstrate the potential of these NPs for targeted therapy.

Pluronic F127 composite hydrogel for the repair of contraction suppressed full-thickness skin wounds in a rabbit model

Hydrogels are commonly used as carriers for cell delivery due to their similarities to the extracellular matrix. A contraction-suppressed full-thickness wound model was used to evaluate the therapeutic potential of Pluronic F127 (PF127) hydrogel loaded with adipose-derived stromal vascular fraction (AdSVF), mesenchymal stem cells (AdMSC), and conditioned media (AdMSC-CM) for the repair of wounds in a rabbit model. The experimental study was conducted on forty-eight healthy adult New Zealand white rabbits randomly divided into eight groups with six animals each and treated with AdSVF, AdMSC, and AdMSC-CM as an injectable or topical preparation. The healing potential of different adipose-derived cell-based and cell-free therapeutics was evaluated based on percentage wound healing, period of epithelialization, epidermal thickness, scar evaluation, histopathology analysis, histochemical evaluation, immunohistochemistry (collagen type I), and hydroxyproline assay by comparing with the positive and negative control. Collagen density analysis using different staining methods, immunohistochemistry, and hydroxyproline assay consistently showed that delivering AdMSC and AdMSC-CM in PF127 hydrogel enhanced epithelialization, collagen production, and organization, contributing to improved tissue strength and quality. Even though allogeneic AdSVF was found to promote wound healing in rabbits, it has a lower potential than AdMSC and AdMSC-CM. The wound healing potential of AdMSC and AdMSC-CM was enhanced when loaded in PF127 hydrogel and applied topically. Even though wounds treated with AdMSC outperformed AdMSC-CM, a significant difference in the healing quality was not observed in most instances, indicating almost similar therapeutic potential. The findings indicate that the wound healing potential of AdMSC and AdMSC-CM was enhanced when loaded in PF127 hydrogel and applied topically. These treatments promoted collagen production, tissue organization, and epidermal regeneration, ultimately improving overall healing outcomes.

Recombinant scFv-Fc Anti-kallikrein 7 Antibody-Loaded Thermosensitive Hydrogels Against Skin Desquamation Disorders.

Human tissue kallikrein-related peptidase 7 (KLK7) is a serine protease implicated in the physiology of skin desquamation, and its uncontrolled activity can lead to chronic diseases such as psoriasis, atopic dermatitis, and Netherton syndrome. For this reason, kallikrein 7 has been identified as a potential therapeutic target. This work aimed to evaluate Pluronic (PL) hydrogels as topical carriers of four specific scFv-Fc antibodies to inhibit KLK7. The hydrogels comprised PL F127 (30% w/v) alone and a binary F127/P123 (28-2% w/v) system. Each formulation was loaded with 1 μg/mL of each antibody and characterized by physicochemical and pharmaceutical techniques, considering antibody-micelle interactions and hydrogel behavior as smart delivery systems. Results showed that the antibodies were successfully loaded into the PL-based systems, and the sol-gel transition temperature was shifted to high values after the P123 addition. The antibodies released from the gels preserved their rheological properties (G' > G'', 35- to 41-fold) and inhibitory activity against KLK7, even after 24 h. This work presented potential agents targeting KLK7 that may provide strategies for treating skin abnormalities.

Maximized nanojunctions in Pd/SnO2 nanoparticles for ultrasensitive and rapid H2 detection

H2 energy has gained massive attraction as a promising candidate for future energy sources. However, the explosive properties of H2 arouse significant safety concerns, emphasizing the need for the development of real-time H2 detection systems. This study presents the fabrication of an ultrasensitive and selective H2 gas sensor using Pd/SnO2 nanoparticles (NPs) synthesized through the utilization of Pluronic F-127. Pluronic F-127 improves the dispersion and regulates the particle size of Pd NPs. Pd/SnO2 NPs, which are comprised of numerous nanojunctions, exhibit H2 response of 27,190 and a response time of 3 s when exposed to 50 ppm of H2 at 100 °C. The practical applicability of Pd/SnO2 NPs was demonstrated by detecting H2 generated from water-splitting cells, exhibiting promising features for H2 energy industries. Overall, the synthetic method of this study proposes advanced strategies for development of sensing materials with maximized gas sensing performance.

Influence of structural organization on mucoadhesive properties of poloxamer-hyaluronic acid-based micelles and hydrogels: From molecular modelling to biointerfaces interactions

New pharmaceutical formulations have been proposed as strategies to improve transport and provide best conditions to control the drug release rate in specific biological environments, such as mucosa surfaces. Herein, formulations containing binary systems Poloxamer (PL) 407 15 % and PL 338 15 %, combined with hyaluronic acid, carrying the local anesthetic bupivacaine (BVC), were studied by molecular dynamics, while other structural parameters were determined by Dynamic Light Scattering for stablishing relationships with mucoadhesive properties and cytotoxicity evaluation. The binary system PL 407 15 %/PL 338 15 % exhibited a well-organized structural morphology, with more hydrated corona, and increased mucoadhesive properties over mucin layers. After hyaluronic acid (HA) incorporation, it was observed an increase on the force of detachment, possibly due to HA role as a linker among mucin layers independently of PL supramolecular structures. On the other hand, the addition of BVC or HA/BVC into the binary system decreased the force of detachment, as a response of augmented of compactness of these hydrogels caused by desolvation of PO core, showing the influence of all components and their chemical interactions into the structural organization and their biopharmaceutical performance relationships.

A biomimetic, triggered‐release micelle formulation of methotrexate and celastrol controls collagen‐induced arthritis in mice

AbstractRheumatoid arthritis (RA) is a systemic autoimmune disease that leads to the destruction of articular cartilage and bone. RA is characterized by immune cell infiltration and abnormal proliferation of synoviocytes in the joints. Herein, we developed a biomimetic formulation via co‐loading the anti‐inflammatory agent Celastrol (Cel) along with the stabilizer Vitamin K (VK) in antirheumatic methotrexate (MTX)‐conjugated Pluronic F127 (F127) micelles. Micelles were then coated with B cell derived membrane, yielding MTX loaded Cel Micelle (CeViM)‐micelle@B, which were investigated for RA treatment. VK, used at levels well within safety margins, was identified as a carrier compound that could stabilize Cel within micelles, increasing the encapsulation efficiency of Cel. In addition, MTX, a front‐line RA therapeutic, was chemically grafted to F127 via a responsive linker sensitive to the chemically reducing environments. As such, CeViM‐micelle@B released pristine MTX in response to the intracellular reducing environments, which combined with Cel to suppress pro‐inflammatory responses. B cell membrane coating enhanced accumulation of CeViM‐micelle@B in joints, leading to a 75% decrease of inflammatory cytokine secretion in vitro, and significantly ameliorated cartilage and bone structures in the collagen‐induced arthritis murine model. Taken together, this biomimetic nanoparticle holds potential as a next‐generation targeted RA treatment.

Effects of Functional Biomaterials on the Attributes of Orally Disintegrating Tablets Loaded with Furosemide Nanoparticles: In Vitro and In Vivo Evaluations.

Furosemide (FUR) is a diuretic used to relieve edema, congestive heart failure, cirrhosis, end-stage renal disease, and hypertension. FUR is a class IV according to the Biopharmaceutics Classification System. It is practically insoluble in water. This study aimed to optimize and formulate porous orally disintegrating tablets (ODTs) prepared by sublimation and loaded with FUR nanoparticles prepared by using a planetary ball mill. Different functional biomaterials called stabilizers were used to stabilize the nanoparticle formula. Pluronic F-127 was the optimum stabilizer in terms of particle size (354.07 ± 6.44), zeta potential (-25.3 ± 5.65), and dissolution efficiency (56.34%). The impact of the stabilizer concentration was studied as well, and a concentration of 3% showed the smallest particle size (354.07 ± 6.44), best zeta potential value (-25.3 ± 5.65), and percentage of dissolution rate (56.34%). A FUR-loaded nanoparticle formula was successfully prepared. The nanoparticle formula was stabilized by using 3% pluronic F-127, and 3% was chosen for further study of the incorporation into oral disintegration tablets prepared by the sublimation technique. The impact of the matrix sublimating agent and superdisintegrant on the ODTs' attributes (in vitro disintegration, wetting time, and in vitro dissolution efficiency) was studied using 32 full factorial designs. In vivo, the diuretic activity was tested for the optimized FUR ODTs by calculating the Lipschitz value using rats as an animal model. The stability of the ODTs loaded with FUR nanoparticles was assessed under accelerated conditions for 6 months. Finally, the ODT formula loaded with FUR NPs showed a rapid onset of action that was significantly faster than untreated drugs. Nanonization and ODT formulation enhances the dissolution rate and bioavailability of FUR. Many factors can be controlled to achieve optimization results, including the formulation and process parameters.

Imbalanced spectral data analysis using data augmentation based on the generative adversarial network

Spectroscopic techniques generate one-dimensional spectra with distinct peaks and specific widths in the frequency domain. These features act as unique identities for material characteristics. Deep neural networks (DNNs) has recently been considered a powerful tool for automatically categorizing experimental spectra data by supervised classification to evaluate material characteristics. However, most existing work assumes balanced spectral data among various classes in the training data, contrary to actual experiments, where the spectral data is usually imbalanced. The imbalanced training data deteriorates the supervised classification performance, hindering understanding of the phase behavior, specifically, sol-gel transition (gelation) of soft materials and glycomaterials. To address this issue, this paper applies a novel data augmentation method based on a generative adversarial network (GAN) proposed by the authors in their prior work. To demonstrate the effectiveness of the proposed method, the actual imbalanced spectral data from Pluronic F-127 hydrogel and Alpha-Cyclodextrin hydrogel are used to classify the phases of data. Specifically, our approach improves 8.8%, 6.4%, and 6.2% of the performance of the existing data augmentation methods regarding the classifier’s F-score, Precision, and Recall on average, respectively. Specifically, our method consists of three DNNs: the generator, discriminator, and classifier. The method generates samples that are not only authentic but emphasize the differentiation between material characteristics to provide balanced training data, improving the classification results. Based on these validated results, we expect the method’s broader applications in addressing imbalanced measurement data across diverse domains in materials science and chemical engineering.

Interfacial Behavior of Biodegradable Poly(lactic-co-glycolic acid)-Pluronic F127 Nanoparticles and Its Impact on Pickering Emulsion Stability.

Biodegradable nanoparticle-based emulsions exhibit immense potential in various applications, particularly in the pharmaceutical, cosmetic, and food industries. This study delves into the intricate interfacial behavior of Pluronic F127 modified poly(lactic-co-glycolic acid) (PLGA-F127) nanoparticles, a crucial determinant of their ability to stabilize Pickering emulsions. Employing a combination of Langmuir balance, surface tension, and diffusion coefficient measurements, we investigate the interfacial dynamics of PLGA-F127 nanoparticles under varying temperature and ionic strength conditions. Theoretical calculations are employed to elucidate the underlying mechanisms governing these phenomena. Our findings reveal a profound influence of temperature-dependent Pluronic layer behavior and electrostatic and steric interactions on the interfacial dynamics. Nonlinear changes in surface tension are observed, reflecting the interplay of these factors. Particle aggregation is found to be prevalent at elevated temperatures and ionic strengths, compromising the stability and emulsification efficiency of the formed emulsions. This work provides insights into the rational design of stable and efficient biodegradable nanoparticle-based Pickering emulsions, broadening their potential applications in various fields.

Role of Unimers to Polymersomes Transition in Pluronic Blends for Controlled and Designated Drug Conveyance.

This study investigates the nanoscale self-assembly from mixtures of two symmetrical poly(ethylene oxide)-poly(propylene oxide)-pol(ethylene oxide) (PEO-PPO-PEO) block copolymers (BCPs) with different lengths of PEO blocks and similar PPO blocks. The blended BCPs (commercially known as Pluronic F88 and L81, with 80 and 10% PEO, respectively) exhibited rich phase behavior in an aqueous solution. The relative viscosity (ηrel) indicated significant variations in the flow behavior, ranging from fluidic to viscous, thereby suggesting a possible micellar growth or morphological transition. The tensiometric experiments provided insight into the intermolecular hydrophobic interactions at the liquid-air interface favoring the surface activity of mixed-system micellization. Dynamic light scattering (DLS) and small-angle neutron scattering (SANS) revealed the varied structural morphologies of these core-shell mixed micelles and polymersomes formed under different conditions. At a concentration of ≤5% w/v, Pluronic F88 exists as molecularly dissolved unimers or Gaussian chains. However, the addition of the very hydrophobic Pluronic L81, even at a much lower (<0.2%) concentration, induced micellization and promoted micellar growth/transition. These results were further substantiated through molecular dynamics (MD) simulations, employing a readily transferable coarse-grained (CG) molecular model grounded in the MARTINI force field with density and solvent-accessible surface area (SASA) profiles. These findings proved that F88 underwent micellar growth/transition in the presence of L81. Furthermore, the potential use of these Pluronic mixed micelles as nanocarriers for the anticancer drug quercetin (QCT) was explored. The spectral analysis provided insight into the enhanced solubility of QCT through the assessment of the standard free energy of solubilization (ΔG°), drug-loading efficiency (DL%), encapsulation efficiency (EE%), and partition coefficient (P). A detailed optimization of the drug release kinetics was presented by employing various kinetic models. The [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] MTT assay, a frequently used technique for assessing cytotoxicity in anticancer research, was used to gauge the effectiveness of these QCT-loaded mixed nanoaggregates.

The artificial intelligence and design of experiment assisted in the development of progesterone-loaded solid-lipid nanoparticles for transdermal drug delivery

The application of Artificial Intelligence (AI) has the potential to revolutionize the formulation development of nanomedicine. This study investigated the physicochemical characteristics of progesterone-loaded solid-lipid nanoparticles (PG-SLNs) produced through an emulsification–ultrasonication process, with a focus on demonstrating the efficacy of this controlled preparation method via the Design of Experiments (DoE) and Artificial Neural Networks (ANN). Critical quality factors, including stearic acid, medium chain triglycerides (MCT), Pluronic F-127, and the amount of propylene glycol (PG), were explored using DoE to streamline experimental setups. The concentration of stearic acid was identified as a crucial factor influencing PG-SLN physicochemical properties, impacting particle size (PS), polydispersity index (PDI), zeta potential (ZP), and %drug loading (%DL). Optimal conditions for PS, PDI, ZP, and %DL were identified. DoE revealed acceptable values across multiple runs, and the ANN model demonstrates high prediction accuracy, surpassing Response Surface Methodology (RSM). The selected PG-SLN formulation was tested for transdermal drug delivery, showing improved permeation compared to PG suspension. Loading with limonene further enhances transdermal drug delivery, attributed to limonene’s role as a penetration enhancer. Moreover, the selected PG-SLN formulation was found to be safe and non-toxic to neuronal cells. The combination of DoE and ANN was proposed to enhance predictive ability. This research highlights the potential of PG-SLNs in transdermal drug delivery, emphasizing the role of limonene as a safe and effective enhancer. The study contributes to the growing interest in applying AI tools in pharmaceutical and biomedical fields for improved predictive modeling.

High-efficiency triplet-triplet annihilation upconversion microemulsion with facile preparation and decent air tolerance.

Current research of triplet-triplet annihilation upconversion (TTA-UC) faces difficulty such as overuse of organic solvents and quenching of excited triplet sensitizers by molecular oxygen. Herein, we propose an efficient and facile preparation strategy of TTA-UC microemulsion to overcome these issues. With simple device and short preparation process, air-stable TTA-UC with a high upconversion efficiency of 16.52% was achieved in microemulsion coassembled from TritonX114, tetrahydrofuran and upconverting chromophores (platinum octaethyl-porphyrin and 9,10-diphenylanthracene). This is comparable to the highest UC efficiency ever reported for TTA-UC microemulsion systems. The excellent UC performance of TX114-THF could be attributed to two perspectives. Firstly, small-size micelle accommodated chromophores up to high concentrations in organic phase, which promoted efficient molecular collision. Additionally, high absorbance at 532nm ensured full use of excitation light, getting more long wavelength photons involved in the TTA-UC process. Moreover, air-stable TTA-UC also performed well in microemulsion with various surfactants, including nonionic surfactants (Tween 20, Tween 80, Triton X-110, Triton X-114), ionic surfactants (sodium dodecyl sulfate, cetyltrimethyl ammonium bromide) and block copolymers (pluronic F127, pluronic P123), through three conjectural assembly models according to the structural characteristics of surfactant molecules (concentrated, uncompacted and scattered). These discoveries could provide estimable reference for selection of surfactants in relevant fields of TTA-UC.

Enhancing solubility and oral bioavailability of rosuvastatin through interpenetrating polymer network (IPN) nanogels: Fabrication, characterization, and in-vivo efficacy assessment

Rosuvastatin (RST) exhibits low aqueous solubility, presenting a challenge for its effective oral administration. The objective of this study is to improve the solubility of RST through the creation and assessment of interpenetrating polymer network (IPN) nanogels. The nanogels were produced via a free radical polymerization method, where hydrophilic polymers β-cyclodextrin (β-CD) and Poloxamer-407 (P407) were combined with the monomer 2-acrylamido-2-methylpropane sulfonic acid (AMPS). Comprehensive characterization of the nanogels included drug loading efficiency, solubility studies, zeta sizer measurements, sol-gel analysis, Fourier-transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), swelling studies, and in-vitro release analysis. Oral toxicity experiments were performed to verify the safety of the β-CD/Poloxamer-407-co-poly (AMPS) IPN nanogels when taken by mouth. The scanning electron microscopy (SEM) investigation unveiled a network structure characterised by porosity and sponginess. The thermal stability and complex synthesis of the nanogel components were validated by the FTIR, TGA, and DSC spectra. X-ray diffraction (XRD) analysis indicated a reduction in the crystallinity of RST within the nanogel matrices. The optimized nanogels formulation demonstrated a particle size of 185.71 ± 1.03 nm. Comparative studies with a reference product highlighted significant enhancements in drug solubility and release characteristics attributed to the fabricated nanogels. Toxicity assessments confirmed the non-toxic nature of the nanogels, supporting their biocompatibility. In-vivo studies using hyperlipidemic animal models validated the anti-hyperlipidemic efficacy of the developed nanogels. The nanogels' biocompatibility, high solubilization capacity, improved dissolution profile, rapid production process, and superior physicochemical properties underscore their potential as an effective oral delivery system for lipophilic drugs.

Design of Carboxymethylcellulose/Poloxamer-Based Bioformulation Embedding Trichoderma afroharzianum for Agricultural Applications.

Microbial biological control agents are believed to be a potential alternative to classical fertilizers to increase the sustainability of agriculture. In this work, the formulation of Trichoderma afroharzianum T22 (T22) spores with carboxymethyl cellulose (CMC) and Pluronic F-127 (PF-127) solutions was investigated. Rheological and microscopical analysis were performed on T22-based systems at three different CMC/PF-127 concentrations, showing that polymer aggregates tend to surround T22 spores, without viscosity, and the viscoelastic properties of the formulations were affected. Contact angle measurements showed the ability of PF-127 to increase the wettability of the systems, and the effect of the formulations on the viability of the spores was evaluated. The viability of the spores was higher over 21 days in all the formulations, compared to the control in water, at 4 and 25 °C. Finally, the effectiveness of the formulations on sweet basil was estimated by greenhouse tests. The results revealed a beneficial effect of the CMC/PF-127 mixture, but none on the formulation with T22. The data show the potential of CMC/PF-127 mixtures for the future design of microorganism-based formulations.

Formulation and evaluation of Dorzolamide hydrochloride microsponges loaded in situ gel for ocular administration

Due to the unique structure of the eye, which inhibits the entry of drug molecules into the desired site, the ophthalmic delivery of the drug has been one of the most challenging tasks for a pharmaceutical scientist. For this reason, in this investigation a novel microsponge for an anti-glaucoma drug, Dorzolamide hydrochloride, was formulated as in situ gel for ocular administration with an aim to improve its therapeutic efficacy and reduce the systemic adverse effects. The microsponges were prepared by the quasi emulsion solvent diffusion method and was incorporated into 20% pluronic F-127 which led to consistent in situ gel at 35°C. They were evaluated for physicochemical properties like pH, gelling capacity, gelation time, rheological properties and release profile and ocular irritancy test. The prepared Dorzolamide hydrochloride microsponges showed high entrapment efficiency of 85% and mean particle size of 2 μm with polydispersity index (PDI) of 0.77 which are ideal for ocular delivery. These microsponges is formulated into in situ gel which showed higher therapeutic efficacy compared to free drug in gel. It was found to be non-irritant to the rabbit’s eye. These results confirms that Dorzolamide hydrochloride microsponges in situ gels have promising features, benefits and advantages for a novel ophthalmic drug delivery to treat glaucoma.

Cellulose- and Saccharide-Based Orally Dispersible Thin Films Transform the Solid States and Dissolution Characteristics of Poorly Soluble Curcumin.

This study aimed at developing and optimizing the orally dispersible thin film (ODTF) containing a plant-derived drug-curcumin (CUR). CUR belongs to a biopharmaceutical classification system (BCS) class IV compound that requires improving its water solubility and tissue permeability preceding formulation. An ODTF was applied to produce a solid dispersion matrix for CUR to resolve such solubility and permeability problems. The film-forming polymers used in the study were cellulose-based (hydroxypropyl methylcellulose/HPMC and carboxymethylcellulose/CMC) and saccharide-based maltodextrin (MDX). Poloxamer (POL) was also employed as surfactant and solubilizer. The solvent casting technique was applied to produce the films. The ethanolic solution of CUR was mixed with an aqueous solution of POLs and then incorporated into different film-forming polymers prior to casting. The processing of the CUR with POL solution was intended to aid in the even dispersion of the drug in the polymeric matrices and enhance the wettability of the films. The physical state and properties of the films were characterized in terms of their morphology, crystallinity of the drug, and phase miscibility of the mixtures. The dissolution profile of the films was also evaluated in terms of dissolution rate and dissolution efficiency. The obtained ODTF products were smooth and flat-surfaced. Physical characterization also indicated that the CUR was homogeneously dispersed in the ODTFs and no longer existed as crystalline material as revealed by X-ray diffraction (XRD). The CUR was also not phase-separated from the films as disclosed by differential scanning calorimetry (DSC). Such dispersion was achieved through the solubilizing effect of POLs and compact polymeric film matrices that prevented the CUR from recrystallization. Furthermore, the ODTFs also improved the dissolution of CUR by 3.2-fold higher than the raw CUR. Overall, cellulose-based films had favorable physical properties compared with saccharide-based films.

Development of novel 3D printable inks for protein delivery

The application of 3D printing technology in the delivery of macromolecules, such as proteins and enzymes, is limited by the lack of suitable inks. In this study, we report the development of novel inks for 3D printing of constructs containing proteins while maintaining the activity of the proteins during and after printing. Different ink formulations containing Pluronic F-127 (20–35 %, w/v), trehalose (2–10 %, w/v) or mannitol, poly (ethylene glycol) diacrylate (PEGDA) (0 or 10 %, w/w), and diphenyl(2,4,6-trimethylbenzoyl) phosphine oxide (TPO, 0 or 0.2 mg/mL) were prepared for 3D-microextrusion printing. The F2 formulation that contained β-galactosidase (β-gal) as a model enzyme, Pluronic F-127 (30 %), and trehalose (10 %) demonstrated the desired viscosity, printability, and dose flexibility. The shear-thinning property of the F2 formulation enabled the printing of β-gal containing constructs with a good peak force during extrusion. After 3D printing, the enzymatic activity of the β-gal in the constructs was maintained for an extended period, depending on the construct design and storage conditions. For instance, there was a 50 % reduction in β-gal activity in the two-layer constructs, but only a 20 % reduction in the four-layer construct (i.e., 54.5 ± 1.2 % and 82.7 ± 9.9 %, respectively), after 4 days of storage. The β-gal activity in constructs printed from the F2 formulation was maintained for up to 20 days when stored in sealed bags at room temperatures (21 ± 2 °C), but not when stored unsealed in the same conditions (e.g., ∼60 % activity loss within 7 days). The β-gal from constructs printed from F2 started to release within 5 min and reached 100 % after 20 min. With the design flexibility offered by the 3D printing, the β-gal release from the constructs was delayed to 3 h by printing a backing layer of β-gal-free F5 ink on the constructs printed from the F2 ink. Finally, ovalbumin as an alternative protein was also incorporated in similar ink compositions. Ovalbumin exhibited a release profile like that of the β-gal, and the release can also be modified with different shape design and/or ink composition. In conclusion, ink formulations that possess desirable properties for 3D printing of protein-containing constructs while maintaining the protein activity during and after printing were developed.

Advanced surface passivation for high-sensitivity studies of biomolecular condensates

Biomolecular condensates are cellular compartments that concentrate biomolecules without an encapsulating membrane. In recent years, significant advances have been made in the understanding of condensates through biochemical reconstitution and microscopic detection of these structures. Quantitative visualization and biochemical assays of biomolecular condensates rely on surface passivation to minimize background and artifacts due to condensate adhesion. However, the challenge of undesired interactions between condensates and glass surfaces, which can alter material properties and impair observational accuracy, remains a critical hurdle. Here, we introduce an efficient, broadly applicable, and simple passivation method employing self-assembly of the surfactant Pluronic F127 (PF127). The method greatly reduces nonspecific binding across a range of condensates systems for both phase-separated droplets and biomolecules in dilute phase. Additionally, by integrating PF127 passivation with the Biotin-NeutrAvidin system, we achieve controlled multipoint attachment of condensates to surfaces. This not only preserves condensate properties but also facilitates long-time fluorescence recovery after photobleaching imaging and high-precision single-molecule analyses. Using this method, we have explored the dynamics of polySIM molecules within polySUMO/polySIM condensates at the single-molecule level. Our observations suggest a potential heterogeneity in the distribution of available polySIM-binding sites within the condensates.

Fluorescence based dopamine detection

Dopamine is an important hormone and neurotransmitter, and its levels in human fluids can indicate stress, depression, and various mental disorders. Food products, as well as medications, affect its level in the human body greatly. Therefore, dopamine monitoring is crucial, and necessary for improving the quality of life. The priority is to search for simple and environmentally friendly sensor systems for the in vitro detection of dopamine, enabling mass utilization.In this study, we explored the use of o-phthalaldehyde (OPA) as an indicator for the detection of dopamine, with fluorescence in the visible range (λex/λem = 390/455 nm), while direct dopamine fluorescence measurement was in the UV range (λex/λem = 280/320 nm). The longer excitation/emission wavelengths of dopamine-OPA complex, as well as lower detection limits, are useful for developing a simple detection method using LEDs. Three types of poloxamers were tested as additives to improve the fluorescence signal from the reaction between dopamine and OPA. Pluronic F127 led to a 16-fold increase in the fluorescence. Utilizing 4% Pluronic F127 with OPA at pH 7 resulted in a linear response within concentration ranges of dopamine (0.5–3 µM), achieving a limit of detection of 0.015 µM. In contrast, a direct detection of dopamine within the same range exhibited a detection limit of 0.13 µM.