Hydrophilic Poly Ethylene Glycol Research Articles

Polyethylene glycol-decorated n-type conducting polymers with improved ion accessibility for high-performance organic electrochemical transistors.

High-performance n-type organic mixed ionic-electronic conductors (OMIECs) are essential for advancing complementary circuits based on organic electrochemical transistors (OECTs). Despite significant progress, current n-type OMIECs often exhibit lower transconductance and slower response times compared to their p-type counterparts, limiting the development of OECT-based complementary circuits. Optimizing the conjugated backbone and side chain structures of OMIECs is critical for enhancing both ion and electron transport efficiencies while maintaining a delicate balance between the two. In this study, hydrophilic polyethylene glycol (PEG) side chains were incorporated into the highly conductive n-type polymer poly(3,7-dihydrobenzo[1,2-b:4,5-b']difuran-2,6-dione) (PBFDO) backbone to achieve this goal. The incorporation of PEG chains improved ion accessibility, and by adjusting the PEG content, the electronic and ionic transport properties were fine-tuned, ultimately enhancing the performance of OECTs and related p-n complementary circuits. The n-type OECTs based on PBFDO-PEG50wt% demonstrated exceptional transfer characteristics, including a transient response time (τON) as low as 72 μs, a high geometry-normalized transconductance exceeding 400 S cm-1, and an impressive μC* value surpassing 720 F cm-1 V-1 s-1. Notably, the use of PBFDO-PEG50wt% in a complementary inverter resulted in a voltage gain of 20 V/V, more than five times higher than that achieved with unmodified PBFDO (<4 V/V). These findings highlight the importance of balancing electron and ion transport characteristics in OMIECs to achieve high performance in OECTs and their associated circuits, and they validate PEG decoration as an effective approach.

A chemically engineered water-soluble block copolymer for redox responsive SO2 release in antibacterial therapy.

Sulfur dioxide (SO2) has emerged as a promising gasotransmitter for various therapeutic applications, including antibacterial activities. However, the potential of polymeric SO2 donors for antimicrobial activities remains largely unexplored. Herein, we report a water-soluble, redox-responsive, SO2-releasing amphiphilic block copolymer poly(polyethylene glycol methyl ether methacrylate) (PPEGMA)-b-poly(2-((2,4-dinitrophenyl)sulfonamido)ethyl methacrylate (PM)) (BCPx) to investigate their antibacterial properties. BCPx contains hydrophilic polyethylene glycol (PEG) pendants and a hydrophobic SO2-releasing PM block, facilitating the formation of self-assembled nanoparticles (BCPxNp) in an aqueous medium, studied by critical aggregation concentration (CAC) measurements, dynamic light scattering (DLS), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). BCPxNp exhibits sustained SO2 release up to 12 h in the presence of glutathione (GSH), with a yield of 30-80% of theoretical SO2 release. In vitro antibacterial studies unveil the outstanding antibacterial activity of BCP3Np against Gram-positive bacteria Bacillus subtilis, as evidenced by FESEM and live/dead cell fluorescence assay. We further elucidate the antibacterial mechanism through reactive oxygen species (ROS) generation studies. Overall, the polymer exhibits excellent biocompatibility at effective antimicrobial concentrations and provides insights into the design of a new class of SO2-releasing polymeric antibacterial agents.

Effect of Hydrophilic Polymers on Solubility Properties of Ketoprofen - 2,5-Dihydroxybenzoic Acid Multicomponent Solids

Ketoprofen is a medicinal compound derivative of phenyl alkanoic acid that works as an anti-inflammatory, antipyretic, and analgesic. In the Biopharmaceutical Classification Systems, ketoprofen is a class II drug with high permeability but low solubility. Due to its low solubility, the absorption and bioavailability of ketoprofen are very limited, which can affect its therapeutic effectiveness. This study aimed to increase ketoprofen's solubility by forming multicomponent solids using 2,5-dihydroxybenzoic acid coformer with adding hydrophilic polymers ((hydroxypropyl)methylcellulose, polyvinylpyrrolidone K90, and polyethylene glycol 4000). The results showed that ketoprofen with 2,5-dihydroxybenzoic acid coformer prepared using the solvent evaporation method formed a eutectic mixture. Adding hydrophilic polymers to the ketoprofen - 2,5-dihydroxybenzoic acid multicomponent solid increased the crystallinity and decreased the melting point of the multicomponent solids. The multicomponent solids of ketoprofen - 2,5-dihydroxybenzoic acid with the addition of hydrophilic polymers had solubility and dissolution efficiency significantly higher (p&lt;0.05) than the ketoprofen - 2,5-dihydroxybenzoic acid multicomponent solids without hydrophilic polymers.

Development and Evaluation of Solid Dispersion-Based Sublingual Films of Nisoldipine.

Nisoldipine (NIS) is a calcium channel blocker that exhibits poor bioavailability (~5%) due to low aqueous solubility and presystemic metabolism in the gut wall. In this context, the present work aimed to develop NIS solid dispersion (NISSD)-based sublingual films using solvent casting technique to improve the dissolution. Phase solubility studies indicated that Soluplus® was the most effective carrier for improving the aqueous solubility of NIS. NISSDs were initially developed using the solvent evaporation method. Fourier transform infrared spectrometric studies were found to display the characteristic vibrational bands related to C=O stretching and N-H deformation in NISSDs, proving the chemical integrity of the drug in NISSDs. Subsequently, bioadhesive sublingual films of NISSDs were formulated using solvent casting method, using hydroxypropyl methyl cellulose (HPMC) E5, E15, and hydroxy ethyl cellulose (HEC EF) as hydrophilic polymers and polyethylene glycol 400 (PEG 400) as plasticizer. The incorporation of NISSDs was found to produce clear films that displayed uniform content. The sublingual film of NISSDs composed of HPMC E5 (2% w/v), was found to display the least thickness (0.29 ± 0.02 mm), the highest folding endurance (168.66 ± 4.50 times), and good bioadhesion strength (12.73 ± 0.503 g/cm2). This film was found to rapidly disintegrate (28.66 ± 3.05 sec) and display near-complete drug release (94.24 ± 1.22) in 30 min. Incorporating NISSDs into rapidly bioadhesive sublingual films considerably improves drug dissolution. Overall, these research outcomes underscored the potential of rapidly dissolving bioadhesive sublingual films to evade gut metabolism and resolve the bioavailability issues associated with oral administration of NIS.

Engineering antifouling membrane with surface segregation agents bearing crosslinked low surface energy segments

Low surface energy material has been considered as the promising material to solve membrane fouling owing to its superior fouling releasing ability, however, its low water wettability would result in decrease of water permeability, which limits its broad application in fabrication of high-performance membranes. Herein, we prepared the amphiphilic crosslinked surface segregation agents based on hydrophilic polyethylene glycol methyl acrylate (PEGMA) segments and crosslinked low surface energy poly(hexafluorobutyl methacrylate) (PHFBM) segments to fabricate antifouling membrane via nonsolvent induced phase separation. The surface segregation of the hydrophilic segments could drag the low surface energy segments onto membrane surface, meanwhile, the crosslinked structure of the low surface energy segment could influence the phase inversion to form a loose separation layer. As a result, amphiphilic membrane surface was constructed with hydrophilic microdomains and low surface energy microdomains as well as underwater superoleophobicity, and the flux of as-prepared membrane was increased slightly with the flux recovery ratio improved from 69.3 % to 92.8 % for separation of BSA solution. Meanwhile, after three cycles of filtration, the flux recovery ratio could maintain a high level. Our study may offer a new route to utilization of low surface energy materials for fabricating antifouling membranes.

High permeability PEG/MXene@MOF membrane with stable interlayer spacing and efficient fouling resistance for continuous oily wastewater purification

Unstable interlayer spacing of lamellar membranes would be rapidly compressed and narrowed under normal high flowrates and concentration polarization effect contributes to reduced permeation and fouling resistance. Herein, a large permeability PEG/MXene@MOF membrane with stable interlayer spacing and superior antifouling property was created via facile interface self-assembly strategy. Metal-organic framework (MOF, UiO-66-NH2) nanoparticles as supports constructed an intercalation-induced structure with hierarchical Ti3C2Tx (MXene) nanosheets, which effectively regulated the interlayer spacing and improved permeability. Hydrophilic polyethylene glycol (PEG) further enhanced the stability of intercalation structure via hydrogen bonding, so that the PEG/MXene@MOF membrane demonstrated excellent swelling resistance with an average layer spacing expansion of only 0.05 nm even after immersion in water for 8 days. Moreover, MOF particles increased the lamellar roughness and interlayer water retention capacity, resulting in the PEG/MXene@MOF membrane with remarkable separation selectivity and powerful fouling resistance (UWOCA >156°, UWOSA <5.5°). Regarding the purification of oil-in-water emulsions stabilized by surfactants, the PEG/MXene@MOF membrane exhibited extremely stable high permeability (1246 ± 12 L m−2 h−1 bar−1) and excellent efficiency (>99.7 %), even during continuous separation of high-viscosity crude oil emulsions for 60 min. In addition, the PEG/MXene@MOF membrane also exhibited superior chemical durability and mechanical robustness in strong-corrosiveness and high-salty environments (72 h), ultrasonic treatments (120 min), bending experiments (100 times) and abrasion tests (20 times). Therefore, this work provided a promising strategy to construct highly permeable membrane with stable interlayer spacing and efficient fouling resistance for practical oily wastewater purification.

Remodeling of Mitochondrial Metabolism by a Mitochondria-Targeted RNAi Nanoplatform for Effective Cancer Therapy.

Emerging evidence has demonstrated the significant contribution of mitochondrial metabolism dysfunction to promote cancer development and progression. Aberrant expression of mitochondrial genome (mtDNA)-encoded proteins widely involves mitochondrial metabolism dysfunction, and targeted regulation of their expression can be an effective strategy for cancer therapy, which however is challenged due to the protection by the mitochondrial double membrane. Herein, a mitochondria-targeted RNAi nanoparticle (NP) platform for effective regulation of mitochondrial metabolism and breast cancer (BCa) therapy is developed. This nanoplatform is composed of a hydrophilic polyethylene glycol (PEG) shell, a hydrophobic poly(2-(diisopropylamino)ethyl methacrylate) (PDPA) core, and charged-mediated complexes of mitochondria-targeting and membrane-penetrating peptide amphiphile (MMPA) and small interfering RNA (siRNA) embedded in the core. After tumor accumulation and internalization by tumor cells, these NPs can respond to the endosomal pH to expose the MMPA/siRNA complexes, which can specifically transport siRNA into the mitochondria to down-regulate mtDNA-encoded protein expression (e.g., ATP6 and CYB). More importantly, because ATP6 down-regulation can suppress ATP production and enhance reactive oxygen species (ROS) generation to induce mitochondrial damage and mtDNA leakage into tumor tissues, the NPs can combinatorially inhibit tumor growth via suppressing ATP production and repolarizing tumor-associated macrophages (TAMs) into tumor-inhibiting M1-like macrophages by mtDNA.

An autocatalytic multicomponent DNAzyme nanomachine for tumor-specific photothermal therapy sensitization in pancreatic cancer

Multicomponent deoxyribozymes (MNAzymes) have great potential in gene therapy, but their ability to recognize disease tissue and further achieve synergistic gene regulation has rarely been studied. Herein, Arginylglycylaspartic acid (RGD)-modified Distearyl acylphosphatidyl ethanolamine (DSPE)-polyethylene glycol (PEG) (DSPE-PEG-RGD) micelle is prepared with a DSPE hydrophobic core to load the photothermal therapy (PTT) dye IR780 and the calcium efflux pump inhibitor curcumin. Then, the MNAzyme is distributed into the hydrophilic PEG layer and sealed with calcium phosphate through biomineralization. Moreover, RGD is attached to the outer tail of PEG for tumor targeting. The constructed nanomachine can release MNAzyme and the cofactor Ca2+ under acidic conditions and self-assemble into an active mode to cleave heat shock protein (HSP) mRNA by consuming the oncogene miRNA-21. Silencing miRNA-21 enhances the expression of the tumor suppressor gene PTEN, leading to PTT sensitization. Meanwhile, curcumin maintains high intracellular Ca2+ to further suppress HSP-chaperone ATP by disrupting mitochondrial Ca2+ homeostasis. Therefore, pancreatic cancer is triple-sensitized to IR780-mediated PTT. The in vitro and in vivo results show that the MNAzyme-based nanomachine can strongly regulate HSP and PTEN expression and lead to significant pancreatic tumor inhibition under laser irradiation.

Designing functionalized polymers through post-polymerization modification of side chain leucine-based polymer

The opportunity to modify the chemical functionality of the incorporated amino acid moiety in side chain amino acid-based polymers provides access to tailor their optical, mechanical, and biological properties. Methacrylate monomers from C-terminus modified amino acids and their subsequent polymerization leads to the formation of polymethacrylate polymers with pendant amine (-NH2) groups. To this end, the post-polymerization reactions on the amine groups offer a facile route to prepare functionalized side chain amino acid-based polymeric materials. Herein, we synthesized side chain L-leucine pendant homopolymer using reversible addition-fragmentation chain transfer (RAFT) polymerization of Boc-L-leucine methacryloyloxyethyl ester (Boc-leu-HEMA) and subsequently the Boc group is deprotected to prepare P(H3N+-leu-HEMA). Post-polymerization modifications on the pendant amine groups were performed to incorporate fluorescent probe, propargyl group, methacrylic moiety, hydrophobic fatty acid, anionic pendant, and hydrophilic polyethylene glycol (PEG) units; which demonstrates an efficient platform to build a library of functionalized polymers from a single polymeric backbone. We have studied the solvatochromic behavior of fluorescence probe bearing polymers using fluorescence spectroscopy. The ability of the pendent methacrylic unit containing polymers to undergo crosslinking and the mechanical properties of the synthesized gel are investigated by the rheological study.

Dynamic migration mechanism of borneol synergistic polyethylene glycol for the construction of silicon-acrylate antifouling coating

Silicone-based coatings are vulnerable to marine fouling organisms in static environments, which seriously hampers its practical application. Here, an amphiphilic acrylate polymer is designed by hydrophilic polyethylene glycol and antibacterial borneol, which is introduced into polydimethylsiloxane (PDMS) by covalent linking to prepare antifouling coatings. XPS and CA tests prove that amphiphilic acrylate polymer can migrate to coating surface in the marine environment to maximize antifouling properties. Mytilus edulis foot protein adhesion test find it can weaken interface force between Mefp-3 and surface. Laboratory antifouling performance evaluations confirm that the coatings are effective against the adhesion of bacteria (86.72 % reduction for E. coli), diatoms (87.76 % reduction for Nitzschia closterium). The good antifouling properties of coatings are ascribed to the synergistic effect among unique bicyclic monoterpene structure of natural non-toxic borneol and amphiphilic acrylate polymer on surface of coatings. Moreover, the coating is less harmful to the marine ecological balance than traditional coatings containing toxic biocides due to the introduction of natural non-toxic borneol. This work contributes new insights in the exploration of environmentally friendly coating with excellent static antifouling performance.

Anti-HER2 Super Stealth Immunoliposomes for Targeted-Chemotherapy.

Liposomes play an important role in the field of drug delivery by virtue of their biocompatibility and versatility as carriers. Stealth liposomes, obtained by surface decoration with hydrophilic polyethylene glycol (PEG) molecules, represent an important turning point in liposome technology, leading to significant improvements in the pharmacokinetic profile compared to naked liposomes. Nevertheless, the generation of effective targeted liposomes-a central issue for cancer therapy-has faced several difficulties and clinical phase failures. Active targeting remains a challenge for liposomes. In this direction, a new Super Stealth Immunoliposomes (SSIL2) composed of a PEG-bi-phospholipids derivative is designed that stabilizes the polymer shielding over the liposomes. Furthermore, its counterpart, conjugated to the fragment antigen-binding of trastuzumab (Fab'TRZ -PEG-bi-phospholipids), is firmly anchored on the liposomes surface and correctly orients outward the targeting moiety. Throughout this study, the performances of SSIL2 are evaluated and compared to classic stealth liposomes and stealth immunoliposomes in vitro in a panel of cell lines and in vivo studies in zebrafish larvae and rodent models. Overall, SSIL2 shows superior in vitro and in vivo outcomes, both in terms of safety and anticancer efficacy, thus representing a step forward in targeted cancer therapy, and valuable for future development.

Exploring the Impact of Head Group Modifications on the Anticancer Activities of Fatty-Acid-like Platinum(IV) Prodrugs: A Structure-Activity Relationship Study.

We conducted the first comprehensive investigation on the impact of head group modifications on the anticancer activities of fatty-acid-like Pt(IV) prodrugs (FALPs), which are a class of platinum-based metallodrugs that target mitochondria. We created a small library of FALPs (1-9) with diverse head group modifications. The outcomes of our study demonstrate that hydrophilic modifications exclusively enhance the potency of these metallodrugs, whereas hydrophobic modifications significantly decrease their cytotoxicity. To further understand this interesting structure-activity relationship, we chose two representative FALPs (compounds 2 and 7) as model compounds: one (2) with a hydrophilic polyethylene glycol (PEG) head group, and the other (7) with a hydrophobic hydrocarbon modification of the same molecular weight. Using these FALPs, we conducted a targeted investigation on the mechanism of action. Our study revealed that compound 2, with hydrophilic modifications, exhibited remarkable penetration into cancer cells and mitochondria, leading to subsequent mitochondrial and DNA damage, and effectively eradicating cancer cells. In contrast, compound 7, with hydrophobic modifications, displayed a significantly lower uptake and weaker cellular responses. The collective results present a different perspective, indicating that increased hydrophobicity may not necessarily enhance cellular uptake as is conventionally believed. These findings provide valuable new insights into the fundamental principles of developing metallodrugs.

Synthesis, characterization, and potential application of polyurethane foam as an effective alternative for dental aspiration substrate in liquid absorption/retention and mechanical properties

AbstractTooth extraction will leave a wound that may cause blood leakage, and the application of liquid‐absorbing hemostatic cotton pressed on the wound can play the effect of pressure to halt bleeding. Unfortunately, the loose structure of the dental absorbent hemostatic cotton causes local slag to fall. Cotton fiber will impede wound heading and possibly drop into the throat and esophagus, thus impacting the life and health of the patient. Therefore, it is of great significance to prepare a material with toughness and high liquid absorption. The polyurethane foams (PUFs) with different chain extension coefficients synthesized from polyether polyol and diphenylmethane diisocyanate (MDI) with water as the blowing agent have excellent toughness and liquid‐absorbing properties with potential applications. The hydrophilic polyethylene glycol (PEG) is introduced into the polyurethane chain segment to form a synergistic effect with the three‐dimensional foam network structure to absorb more wound exudate. The hydrophobic PUFs can be applied to wounds with less exudate and the hydrophilic PUFs can be applied to chronic wounds with more exudate. The porous structure gives the PUF a strong loading capacity and promotes the wound‐healing effect. The PUFs exhibit good liquid absorption/retention performance in both 0.9 wt% NaCl solution and DI water, especially PUF‐1.10 has an ultimate DI water absorbency of nearly 840%. According to the performance, comparison of the current market commonly used dental absorbent hemostatic cotton; PUF‐1.10 is considered a promising candidate for replacing traditional dental commercial absorbent hemostatic slag‐fall cotton in liquid absorption/retention and mechanical properties.

Mitochondria-targeted nanoparticles overcome chemoresistance via downregulating BACH1/CD47 axis in ovarian carcinoma

The platinum-based chemotherapy is a routine strategy for the treatment of ovarian cancer, while it is prone to chemoresistance in clinical, which hinders the treatment. Therefore, it is urgently needed to elucidate the underlying mechanism of drug resistance and form the appropriate strategy. The sequencing results showed that cisplatin (DDP) resistant ovarian cancer overexpressed BTB and CNC homology 1 (BACH1), and up-regulated the “don't eat me” signal CD47. We identified that hemin, a BACH1 inhibitor, could effectively down-regulate BACH1 and simultaneously inhibit CD47. Moreover, hemin has a synergistic effect with DDP. We designed a pH-responsive nanoparticle (H/D@FA–CaP–NPs) in which folic acid (FA) ensured targeting of ovarian cancer cells, while hemin inhibited BACH1 as well as down-regulated CD47, achieving the promotion of apoptosis of tumor cells and inducing phagocytosis of tumors by macrophages. Moreover, hemin has a synergistic effect with DDP to promote apoptosis of tumor cells. Structurally, hemin and DDP was encapsulated within hydrophobic 1,2-distearoyl-sn‑glycero-3-phospho-ethanolamine (DSPE) to form a tight core, and hydrophilic polyethylene glycol 2000 (PEG2000) and calcium phosphate (CaP) formed the outside shell, and FA was modified on the surface of nanoparticles. In terms of function, (a) FA enhanced the active targeting of nanoparticles to tumors; (b) NPs targeted mitochondria to induce reactive oxygen species (ROS) production; (c) hemin encapsulated in nanoparticles could specifically target BACH1, thereby down regulating CD47; (d) hemin had a synergistic effect with DDP, thus augmenting the chemotherapy. Altogether, mitochondria-targeted nanoparticles H/D@FA–CaP–NPs promoted tumor apoptosis and mobilized phagocytosis to treat tumor, providing a novel scheme for clinical treatment of cisplatin-resistant ovarian carcinoma.

Green Synthesis and the Evaluation of a Functional Amphiphilic Block Copolymer as a Micellar Curcumin Delivery System.

Polymer micelles represent one of the most attractive drug delivery systems due to their design flexibility based on a variety of macromolecular synthetic methods. The environmentally safe chemistry in which the use or generation of hazardous materials is minimized has an increasing impact on polymer-based drug delivery nanosystems. In this work, a solvent-free green synthetic procedure was applied for the preparation of an amphiphilic diblock copolymer consisting of biodegradable hydrophobic poly(acetylene-functional carbonate) and biocompatible hydrophilic polyethylene glycol (PEG) blocks. The cyclic functional carbonate monomer 5-methyl-5-propargyloxycarbonyl-1,3-dioxane-2-one (MPC) was polymerized in bulk using methoxy PEG-5K as a macroinitiator by applying the metal-free organocatalyzed controlled ring-opening polymerization at a relatively low temperature of 60 °C. The functional amphiphilic block copolymer self-associated in aqueous media into stable micelles with an average diameter of 44 nm. The copolymer micelles were physico-chemically characterized and loaded with the plant-derived anticancer drug curcumin. Preliminary in vitro evaluations indicate that the functional copolymer micelles are non-toxic and promising candidates for further investigation as nanocarriers for biomedical applications.

NIR-Triggered On-Demand Nitric Oxide Release for Enhanced Synergistic Phototherapy of Hypoxic Tumor.

Hypoxia of tumor microenvironments is a major factor restricting tumor treatment, which causes progression and metastasis of tumor. The hypoxic tumor microenvironment not only makes the traditional treatment method, such as chemotherapy, ineffective but also hinders the O2-dependent treatments, such as photodynamic therapy (PDT). Recently, stimuli-responsive nitric oxide (NO) donors have attracted extensive research interest in hypoxic tumor treatment because the NO release process is O2-independent. Besides, NO can distribute more uniformly than drug molecules and more widely than the PDT-generated active species due to its strong diffusion ability (200 μm in cells) and long lifetime (2 s in cells). Encouraged by these advantages, a near infrared light-triggered NO release polymeric nanoplatform (P1-CapNO NPs) was constructed by a thermally sensitive NO release unit, a photothermal unit, and a hydrophilic polyethylene glycol unit. P1-CapNO NPs possess strong absorption in the NIR region (the wavelength of maximal absorption peak was 790 nm with a molar absorption coefficient of 2.4 × 105 M-1 cm-1), great photothermal conversion efficiency (23.8%), and NO release ability (the released NO concentration can reach 1.3 μM) under 808 nm laser irradiation. Owing to these advantages, the great synergistic antitumor effect can be achieved in vitro and in vivo even under the hypoxic environment. The synergistic therapeutic strategy in this work could bypass the obstacles caused by hypoxia in tumor treatment and provide a reference for building a NO-involved therapeutic platform.

Sustainable Cotton Gin Waste/Polycaprolactone Bio-Plastic with Adjustable Biodegradation Rate: Scale-Up Production through Compression Moulding.

Cotton gin trash (CGT), a lignocellulosic waste generated during cotton fibre processing, has recently received significant attention for production of composite bio-plastics. However, earlier studies were limited to either with biodegradable polymers, through small-scale solution-casting method, or using industrially adaptable extrusion route, but with non-biodegradable polymers. In this study, a scale-up production of completely biodegradable CGT composite plastic film with adjustable biodegradation rate is proposed. First using a twin screw extruder, the prepared CGT powder was combined with polycaprolactone (PCL) to form pellets, and then using the compressing moulding, the pellets were transformed into bio-plastic composite films. Hydrophilic polyethylene glycol (PEG) was used as a plasticiser in the mixture and its impact on the biodegradation rate was analysed. The morphology of CGT bio-plastic composite films showed even distribution of CGT powder within the PCL matrix. The CGT incorporation improved the UV resistance, thermal stability, and Young's modulus of PCL material. Further, the flexibility and mixing properties of the composites were improved by PEG. Overall, this study demonstrated a sustainable production method of CGT bio-plastic films using the whole CGT and without any waste residue produced, where the degradation of the produced composite films can be adjusted to minimise the environmental impact.

Exploration of the Nucleation Pathway for Supramolecular Fibers

The pathway for supramolecular fiber formation is coupled with the underlying order of the self-assembling molecules. Here, we report on atomistic molecular dynamics simulations to characterize the initial stages of the self-assembly of a model drug amphiphile in an aqueous solution. We perform two-dimensional metadynamics calculations to characterize the assembly space of this model drug amphiphile─Tubustecan, TT1. TT1 is composed of the hydrophobic anticancer drug, Camptothecin (CPT), conjugated to a hydrophilic polyethylene glycol (PEG) chain. We find that the aromatic stacking of CPT drives the formation of a higher-density liquid droplet. This droplet elongates and can form a higher-ordered supramolecular assembly upon reorganizing and forming an interface and additional aromatic stacking of the drugs. We show that novel reaction coordinates tailored to this class of molecules are essential in capturing the underlying degree of molecular order upon assembly. This approach can be refined and extended to characterize the supramolecular assembly pathway of other molecules containing aromatic compounds.

The Electro-Spun Sublingual Film Containing Curcumin Micelles

Hydrophilic polymers D-tocopheryl polyethylene glycol succinate (TPGS-1000) and Poloxamer-188 were combined for the formulation of a sublingual film that aids in improving the oral bioavailability of the drug curcumin, which is not very soluble. For the formulation of micelles, the thin-film hydration technique was used and then electro-spun into a sublingual film that contained 13 % w/v PVP. Following that, prepared micelles and films were assessed and evaluated (particle size, PDI, zeta potential, %EE, pH studies, disintegration time, and in vitro drug release). According to the findings, the average particle size of the blended micelles was 230.2 nm. The ideal formulation of mixed micelles had a mean zeta potential and PDI of 20.73 mV and 0.258±0.038, respectively. Additionally, an entrapment efficiency of 82% was reached. In an aqueous medium, the film disintegrated in 40±10 seconds. Micelles were incorporated into the film without losing their integrity. Importantly, as compared to a pure drug, the films with micelles put on them showed improved bioavailability, high permeability and rapid absorption of the curcumin. Compared to the pure drug, the bioavailability of the films was increased by around 2.18 times due to the presence of mixed micelles loaded with curcumin. The results also showed that micelles-loaded sublingual films performed well in vitro for bioavailability improvement. In the end, it was found that films containing a mixture of poloxamer-188 and TPGS-1000 micelles would function effectively as carriers to boost curcumin’s bioavailability.

Hydrogen sulfide detection induced burst release of model drug from polymeric micelles

In this study, a poly(ester-amide)-based amphiphilic polymer (named P1) is prepared for the burst release of a model drug, rhodamine, from polymeric micelles, triggered by hydrogen sulfide (H2S) detection. P1 was synthesized by the Passerini multicomponent polymerization of a hydrophobic H2S-specific unit (M1) with 6-isocyanohexanoic acid, and hydrophilic polyethylene glycol (PEG) dicarboxylic acid. When P1 self-assembles in water, it generates polymeric micelles consisting of a hydrophilic PEG shell and a hydrophobic core derived from M1 with 6-isocyanohexanoic acid. P1 micelles exhibited selective colorimetric (colorless to yellow) and fluorometric (non-emissive to blue emission) H2S detection in water. The limit of detection was as low as 0.09 mM. Upon the exposure of H2S to a P1 micelle solution encapsulating the hydrophobic model drug, rhodamine, H2S detection induced a sequential and self-destructive elimination process of the polymer backbone, resulting in the swelling of the micelles and the abrupt release of rhodamine.