High Molecular Weight Research Articles

Template Assisted Synthesis of Linear [5]Catenane by Post-Functionalization of Templated [2]Catenane and Using Click Reaction.

Polymers with all mechanically interlocked rings, such as linear [n]catenanes, have great potential as functional materials due to possible higher degrees of freedom that may contribute to their flexibility but remain elusive. All the synthetic methods used to prepare such a polymer yield mixtures of products.In the absence of higher molecular weight linear [n]catenanes, emphasis on synthesizing low molecular weight oligomers is being pursued. Here, we have described the synthesis of a linear [5]catenane by post-functionalizing a Co(III) templated [2]catenane having a pyridine-diamide unit free for further metal ion coordination. Two molecules were synthesized with suitable threading groups: one, two terminal azide groups, and two, with two terminal alkyne groups to form two [3]pseudorotaxane utilizing Co(III) coordination. These units were then joined, forming a macrocycle, using click reaction, giving the desired metallated linear [5]catenane in 40% yield. Removal of metal ions leads to linear [5]catenane. In addition, the formation of linear [3] and [2]catenane are also observed. All synthesized structures have been isolated by column chromatographic technique and characterized by1H-NMR,13C-NMR, and mass spectroscopy.

Pleurotus sajor-caju (Fr.) Singer β-1,3-Glucanoligosaccharide (Ps-GOS) Suppresses RANKL-Induced Osteoclast Differentiation and Function in Pre-Osteoclastic RAW 264.7 Cells by Inhibiting the RANK/NFκB/cFOS/NFATc1 Signalling Pathway.

Edible grey oyster mushroom, Pleurotus sajor-caju, β (1,3), (1,6) glucan possesses a wide range of biological activities, including anti-inflammation, anti-microorganism and antioxidant. However, its biological activity is limited by low water solubility resulting from its high molecular weight. Our previous study demonstrated that enzymatic hydrolysis of grey oyster mushroom β-glucan using Hevea β-1,3-glucanase isozymes obtains a lower molecular weight and higher water solubility, Pleurotus sajor-caju glucanoligosaccharide (Ps-GOS). Additionally, Ps-GOS potentially reduces osteoporosis by enhancing osteoblast-bone formation, whereas its effect on osteoclast-bone resorption remains unknown. Therefore, our study investigated the modulatory activities and underlying mechanism of Ps-GOS on Receptor activator of nuclear factor kappa-Β ligand (RANKL) -induced osteoclastogenesis in pre-osteoclastic RAW 264.7 cells. Cell cytotoxicity of Ps-GOS on RAW 264.7 cells was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay and its effect on osteoclast differentiation was determined by tartrate-resistant acid phosphatase (TRAP) staining. Additionally, its effect on osteoclast bone-resorptive ability was detected by pit formation assay. The osteoclastogenic-related factors were assessed by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR), Western blot and immunofluorescence. The results revealed that Ps-GOS was non-toxic and significantly suppressed the formation of mature osteoclast multinucleated cells and their resorption activity by reducing the number of TRAP-positive cells and pit formation areas in a dose-dependent manner. Additionally, Ps-GOS attenuated the nuclear factor kappa light chain-enhancer of activated B cells' P65 (NFκB-P65) expression and their subsequent master osteoclast modulators, including nuclear factor of activated T cell c1 (NFATc1) and Fos proto-oncogene (cFOS) via the NF-κB pathway. Furthermore, Ps-GOS markedly inhibited RANK expression, which serves as an initial transmitter of many osteoclastogenesis-related cascades and inhibited proteolytic enzymes, including TRAP, matrix metallopeptidase 9 (MMP-9) and cathepsin K (CTK). These findings indicate that Ps-GOS could potentially be beneficial as an effective natural agent for bone metabolic disease.

Survey of pharmaceutical industry's best practices around in vitro transporter assessment and Implications for Drug Development: Considerations from the IQ Transporter Working Group.

The IQ Transporter Working Group had a rare opportunity to analyse a cross-pharma collation of in vitro data and assay methods for the evaluation of drug transporter substrate and inhibitor potential. Experiments were generally performed in accordance with regulatory guidelines. Discrepancies, such as not considering the impact of pre-incubation for inhibition and free or measured in vitro drug concentrations, may be due to the retrospective nature of the dataset and analysis. Lipophilicity was a frequent indicator of cross-transport inhibition (P-gp, BCRP, OATP1B and OCT1) with high molecular weight ({greater than or equal to}500 Da) also common for OATP1B and BCRP inhibitors. A high level of overlap in in vitro inhibition across transporters was identified for BCRP, OATP1B1 and MATE1 suggesting that prediction of DDIs for these transporters will be common. In contrast inhibition of OAT1 did not coincide with inhibition of any other transporter. Neutrals, bases, and compounds with intermediate-high lipophilicity tended to be P-gp and/or BCRP substrates whilst compounds with MW <500 Da tended to be OAT3 substrates. Interestingly the majority of in vitro inhibitors were not reported to be followed up with a clinical study by the submitting company, whilst those compounds identified as substrates generally were. Approaches to metabolite testing were generally found to be similar to parent testing with metabolites generally being equally or less potent than parent compounds. However, examples where metabolites inhibited transporters in vitro were identified supporting the regulatory requirement for in vitro testing of metabolites to enable integrated clinical DDI risk assessment. Significance Statement A diverse dataset showed transporter inhibition often correlated with lipophilicity and molecular weight (>500 Da). Overlapping transporter inhibition was identified, particularly that inhibition of BCRP, OATP1B1 and MATE1 was frequent if the compound inhibited other transporters. In contrast inhibition of OAT1 did not correlate with the other drug transporters tested.

Macrocrowding of Polyethylene Glycol Facilitates the Formation of Polydopamine Nanoparticles and Derivatives via Depletion Stabilization

Mussel‐inspired polydopamine nanoparticles (PDA NPs) show promise in biosensing, drug delivery, and energy storage. However, it is still difficult to obtain monodispersed PDA NPs and metal‐containing PDA NPs in mild aqueous conditions. Herein, we report a facile strategy to modulate the growth and formation of PDA NPs in a macrocrowding condition using inert polymers as crowders. Our results show that both high concentrations and molecular weights are important for polymer‐enabled particle stabilization. Importantly, we demonstrate that only polymers with a weak interaction with PDA could facilitate PDA NPs formation. Lastly, we show that this strategy could be extended to metal‐containing PDA derivatives, and enzyme‐encapsulated PDA NPs. Overall, our findings offer a simple and effective approach for producing uniform biocompatible nanomaterials, while also shedding light on the role of depletion forces in nanoparticle stabilization in solution.

Enhanced Electroactive Phases of Poly(vinylidene Fluoride) Fibers for Tissue Engineering Applications.

Nanofibrous materials generated through electrospinning have gained significant attention in tissue regeneration, particularly in the domain of bone reconstruction. There is high interest in designing a material resembling bone tissue, and many scientists are trying to create materials applicable to bone tissue engineering with piezoelectricity similar to bone. One of the prospective candidates is highly piezoelectric poly(vinylidene fluoride) (PVDF), which was used for fibrous scaffold formation by electrospinning. In this study, we focused on the effect of PVDF molecular weight (180,000 g/mol and 530,000 g/mol) and process parameters, such as the rotational speed of the collector, applied voltage, and solution flow rate on the properties of the final scaffold. Fourier Transform Infrared Spectroscopy allows for determining the effect of molecular weight and processing parameters on the content of the electroactive phases. It can be concluded that the higher molecular weight of the PVDF and higher collector rotational speed increase nanofibers' diameter, electroactive phase content, and piezoelectric coefficient. Various electrospinning parameters showed changes in electroactive phase content with the maximum at the applied voltage of 22 kV and flow rate of 0.8 mL/h. Moreover, the cytocompatibility of the scaffolds was confirmed in the culture of human adipose-derived stromal cells with known potential for osteogenic differentiation. Based on the results obtained, it can be concluded that PVDF scaffolds may be taken into account as a tool in bone tissue engineering and are worth further investigation.

A facile and scalable method to synthesize PEGylated PDMAEMA for gene delivery.

In recent years, cationic polymer vectors have been viewed as a promising method for delivering nucleic acids. With the advancement of synthetic polymer chemistry, we can control chemical structures and properties to enhance the efficacy of gene delivery. Herein, a facile, cost-effective, and scalable method was developed to synthesize PEGylated PDMAEMA polymers (PEO-PDMAEMA-PEO), where PEGylation could enable prolonged polyplexes circulation time in the blood stream. Two polymers of different molecular weights were synthesized, and polymer/eGFP polyplexes were prepared and characterized. The correlation between polymers' molecular weight and physicochemical properties (size and zeta potential) of polyplexes was investigated. Lipofectamine 2000, a commercial non-viral transfection reagent, was used as a standard control. PEO-PDMAEMA-PEO with higher molecular weight exhibited slightly better transfection efficiency than Lipofectamine 2000, and the cytotoxicity study proved that it could function as a safe gene vector. We believe that PEO-PDMAEMA-PEO could serve as a model to investigate more potential in the gene delivery area.

Integrated neuromuscular training intervention applied in schools induces a higher increase in salivary high molecular weight adiponectin and a more favorable body mass index, cardiorespiratory fitness and muscle strength in children as compared to the traditional physical education classes.

High-molecular-weight adiponectin (HMW-adiponectin) is a cardio-metabolic health protector. Objectives: (1) to compare body mass index (BMI), cardiorespiratory fitness (CRF) and muscle strength (MS) in healthy school-children depending on their baseline salivary-HMW-adiponectin concentration; and (2) to apply a 3-month integrated neuromuscular training (INT) and evaluate its effects on salivary-HMW-adiponectin concentration, BMI, CRF and MS in the same children. Additional goal: to identify if any potential changes during the 3-month period may be related to a potential change in salivary-HMW-adiponectin concentration. Ninety children (7.4 ± 0.3 years) were recruited in primary schools and randomly allocated into control or intervention group. The intervention consisted of a 3-month INT applied during physical education (PE) classes, twice-weekly, while the control group had traditional PE classes. Body mass and height were measured, BMI was calculated and HMW-adiponectin was quantified in saliva. To assess CRF and MS, 800 m-run and hand-dynamometry were applied, respectively. All measurements were performed twice, at baseline and after 3 months. Children with higher baseline salivary-HMW-adiponectin have more favorable BMI (p = 0.006) and slightly higher CRF (p = 0.017) in comparison to the children with lower baseline salivary-HMW-adiponectin. There were no big changes after the 3-month-period neither in the control, nor the INT group. However, it is worthy to note that the INT induced slightly higher increase in salivary-HMW-adiponectin (p = 0.007), and a slightly higher improvement in BMI (p = 0.028), CRF (p = 0.043) and MS (p = 0.003), as compared to the traditional PE classes. Finally, the INT-induced improvement in CRF was associated with the increased post-salivary-HMW-adiponectin concentration (p = 0.022). Main findings may suggest the potential utility of an INT as a cost-effective strategy that can be applied in schools to induce cardio-protective effects in school-children.

Abstract PO4-25-08: Secretory breast carcinoma (SBC) in an 8-year-old male: Report of an exceptionally rare case with review of clinicoradiologic and pathomolecular findings of SBC in the male pediatric population

Abstract Secretory breast carcinoma (SBC) is a rare and distinct disease, comprising approximately 0.01% of all breast carcinomas. This is a case of an 8-year-old boy who presented with a 1.5-year history of a non-tender, slowly enlarging left subareolar mass, not associated with nipple discharge. Serologic workup revealed minimally elevated prolactin with normal-range FSH, LH, estradiol and testosterone, as well as normal-range beta-hCG, LDH and AFP. Ultrasound showed a circumscribed solid hypoechoic lesion with internal arterial vascularity, favoured to represent a sebaceous cyst. Excisional biopsy was performed, and histologic examination revealed the classic intra- and extracellular secretory material typically seen in SBC. Immunohistochemical (IHC) stains for mammaglobin, S-100 and high molecular weight keratin (CK5) were positive. ER was positive, though not strong staining, and PR and HER2 were negative. A screen for NTRK fusions with pan-TRK IHC was positive. No skin, perineural or lymphovascular invasion was identified. RNA-based NGS demonstrated ETV6-NTRK3 fusion and confirmed the diagnosis of SBC. The patient underwent mastectomy and SLNB, which showed no residual tumor and no positive lymph nodes. A full metastatic work-up was not performed and the patient did not receive neoadjuvant therapy. First described as “juvenile breast carcinoma,” SBC has since been recognized to occur across a wide age range, with most cases occurring in adults. SBC in male pediatric patients is exceptionally rare, with fewer than 20 cases reported in the literature. In this demographic, SBC is usually detected clinically as a subareolar mass not associated with nipple discharge, and appears as a well-circumscribed mass on imaging, mimicking benign entities. SBC is usually detected at a low stage, treated surgically, and follows a clinically indolent course with excellent outcomes. Positive axillary nodes have been identified in a few male children, who subsequently underwent chemo- and/or radiotherapy, with no recorded recurrences in these cases. Distant metastases are an extremely uncommon feature of SBC and have not been reported in the pediatric male population; however, due to the rarity of this diagnosis, particularly in this demographic, robust long-term follow-up data are still lacking. The name “secretory” derives from the histologic appearance of the dense eosinophilic secretory material seen in tumor lumina and bubbly material in the cytoplasm of tumor cells. Similar to the cytologic characteristics of other translocation-driven neoplasms, SBC shows minimal pleomorphism. Mitoses are absent or rare. IHC stains are typically positive for S-100 and high molecular weight keratins and negative for ER, PR, and HER2. Despite the immunophenotypic similarities to triple negative/basal-like carcinomas (TNBC/BLC) the molecular relationship between SBC and TNBC/BLC is unclear. Though initially defined by its distinctive secretions on histology, SBC is now chiefly characterized by a balanced translocation, t(12;15)(p13;q25), resulting in oncogenic ETV6-NTRK3 fusion. Recent cases have demonstrated this using a variety of molecular techniques, including FISH, RT-PCR, and in our case, RNA-based NGS. This translocation also characterizes non-breast secretory carcinomas and has been identified in several other neoplasms, including pediatric mesenchymal tumours and adult acute myeloid leukemia. The rarity of SBC, particularly in the male pediatric population, underlines the necessity of this case report. Additionally, this case highlights the importance of considering SBC as a potential diagnosis in male children presenting with a breast mass, even in the presence of benign imaging characteristics. Table 1: Clinicoradiologic and pathomolecular characteristics of SBC in pediatric males AND, axillary node dissection; CT, chemotherapy; ER, estrogen receptor; FISH, fluorescence in situ hybridization; LE, local excision; MRM, modified radical mastectomy; nd, no data; NED, no evidence of disease; NGS, next-generation sequencing; NS, nodal sampling; PA, periareolar; PR, progesterone receptor; RA, retroareolar; RM, radical mastectomy; PCR, polymerase chain reaction; RT, radiotherapy; SA, subareolar; SLNB, sentinel lymph node biopsy; SM, simple mastectomy; WLE, wide local excision *Not reported as strong staining Table 2: Immunohistochemical phenotype of secretory breast carcinoma EMA, epithelial membrane antigen; ER, estrogen receptor; PR, progesterone receptor *Not reported as strong staining Table 3: Laboratory investigations AFP, alpha fetoprotein; FSH, follicle stimulating hormone; hCG, human chorionic gonadotropin; LDH, lactate dehydrogenase; LH, luteinizing hormone Citation Format: Rebecca Brassington, Svetlana Silverman, Ioana Bratu. Secretory breast carcinoma (SBC) in an 8-year-old male: Report of an exceptionally rare case with review of clinicoradiologic and pathomolecular findings of SBC in the male pediatric population [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO4-25-08.

Water-soluble compounds from Lignosus rhinocerus TM02® (xLr™) modulate ACE2 activity and inhibit its interaction with SARS-CoV-2 Spike-Protein

Water-soluble compounds from Lignosus rhinocerus TM02® (xLr™) modulate ACE2 activity and inhibit its interaction with SARS-CoV-2 Spike-Protein

Highly water-soluble and migration stable photoinitiators from meso-2,3-dimercaptosuccinic acid

A facile route to prepare highly water-soluble and migration stable Type I and Type II photoinitiators is reported. The mono- or doubly 2-hydroxy-4′-(2-hydroxyethoxy)-2 methylpropiophenone (I2959), 1-hydroxycyclohexyl phenyl ketone (I184) and benzophenone (BP) functionalized meso-2,3-dimercaptosuccinic acid (DMSA) salts with 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) or sodium counterion (DMSA-I2959-DBU, DMSA-I184-Na, DMSA-BP-Na, DMSA-BP-DBU) are synthesized in one-pot thiol-Michael addition reaction. Although DMSA-I2959-DBU and DMSA-I184-Na have higher water solubility (e.g. 16 times higher than that of I2959 for the first one) than I2959 and I184, BP functionalized PIs are not stable in water. The synthesized photoinitiators have similar or higher λmax compared to the commercial ones they are synthesized from. The decomposition mechanism and the radical generations are investigated by steady state photolysis and electron spin resonance (ESR). They show reasonable photoinitiating reactivity towards (meth)acrylic double bonds except the I184-based one. The higher migration stability of photoinitiators (DMSA-I2959-DBU has ∼4 times higher than that of I2959), is due to their and unreactive photodecomposition byproducts’ high molecular weight.

Direct electrospinning for producing multiple activity nanofibers consisting of aggregated luteolin/hydroxypropyl-gamma-cyclodextrin inclusion complex

Hydroxypropyl-gamma-cyclodextrin (HPγCD) inclusion complex nanofibers (Lut/HPγCD-IC-NF) containing Luteolin (Lut) were prepared by electrospinning technology. Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) spectra confirmed the formation of Lut/HPγCD-IC-NF. Scanning electron microscopy (SEM) images showed that the morphology of Lut/HPγCD-IC-NF was uniform and bead-free, suggesting that self-assembled aggregates, macromolecules with higher molecular weights, were formed by strong hydrogen bonding interactions between the cyclodextrin inclusion complexes. Confocal laser scanning microscopy (CLSM) images showed that Lut was distributed in Lut/HPγCD-IC-NF. Proton nuclear magnetic resonance (1H NMR) spectroscopy revealed the change in chemical shift of the proton peak between Lut and HPγCD, confirming the formation of inclusion complex. Thermogravimetric analysis (TGA) proved that Lut/HPγCD-IC-NF had good thermal stability. The phase solubility test confirmed that HPγCD had a solubilizing effect on Lut. When the solubility of HPγCD reached 10 mM, the solubility of Lut increased by 15-fold. The drug loading test showed that the content of Lut in fibers reached 8.57 ± 0.02 %. The rapid dissolution experiment showed that Lut/HPγCD-IC-NF dissolved within 3 s. The molecular simulation provides three-dimensional evidence for the formation of inclusion complexes between Lut and HPγCD. Antibacterial experiments showed that Lut/HPγCD-IC-NF had enhanced antibacterial activity against S. aureus. Lut/HPγCD-IC-NF exhibited excellent antioxidant properties with a free radical scavenging ability of 89.5 ± 1.1 %. In vitro release experiments showed Lut/HPγCD-IC-NF had a higher release amount of Lut. In conclusion, Lut/HPγCD-IC-NF improved the physicochemical properties and bioavailability of Lut, providing potential applications of Lut in the pharmaceutical field.

Promotion of chain growth and suppression of chain transfer by 2-methoxy group in diarylmethyl moiety in pyridine-imine nickel- and palladium-catalyzed ethylene (co)polymerization

Diarylmethyl substituents are commonly used to prevent chain transfer in late-transition metal-catalyzed ethylene polymerization. However, this substituent is not effective in inhibiting chain transfer in the pyridine-imine system. In this study, we introduced substituents at the 2-position of the diarylmethyl moiety to synthesize high molecular weight polyethylene in the pyridine-imine system. Using this strategy, we synthesized two pyridine-imine ligands with either ethyl or methoxy at the 2-position diarylmethyl moiety, along with their corresponding nickel and palladium complexes. These complexes were then utilized for ethylene (co)polymerization. The catalysts with OMe exhibited significantly higher polymerization activity (an order of magnitude, 105 vs. 104 g/(mol Ni·h)) compared to the corresponding Et catalysts. In addition, it was found that polyethylene produced from nickel and palladium catalysts with OMe has higher molecular weights than that produced from ethyl nickel and palladium catalysts. The nickel system produces polyethylene with a molecular weight up to an order of magnitude higher (an order of magnitude, 13.0–13.6 vs. 3.1–4.0 kg/mol). Similar results were also observed in the palladium-catalyzed copolymerization of ethylene with MA. Notably, the palladium catalyst with OMe has a significantly higher capacity for MA insertion (three times, 1.68–4.74 vs. 5.00–11.73 mol%) than the ethyl palladium catalyst, despite their similar spatial steric structures. The observed phenomenon may be attributed to the weak interaction between OMe and the metal center. In addition, 13C NMR analysis showed that the palladium-catalyzed polyethylene and E-MA copolymers are hyperbranched polymers, with the polar groups located at the ends of the branches.

Withdrawn: The Property of a Novel Cross‐Linked Foam from Thermoplastic Phenol‐Terminated Polyphenylene Ether Resin with High Molecular Weight Cured by Hydroxymethylated Phenol‐Terminated Polyphenylene Ether Resin with Low Molecular Weight

AbstractWithdrawal: Tingting Li, Wenhan Gao, Ruobing Yu, Rui Xia, Bu Chang, The Property of A Novel Crosslinked Foam from Thermoplastic Phenol‐Terminated Polyphenylene Ether Resin with High Molecular Weight (MPF) Cured by Hydroxymethylated Phenol‐Terminated Polyphenylene Ether Resin with Low Molecular Weight (LPR), Macromolecular Chemistry and Physics, 5th October 2023,(https://onlinelibrary.wiley.com/doi/10.1002/macp.202300247).The above article, published online on 5th October 2023, on Wiley Online Library (https://doi.org/10.1002/macp.202300247), has been withdrawn by agreement between the journal Editor in Chief, Mara Staffilani, and Wiley‐VCH GmbH, Weinheim. The withdrawal has been agreed because the authors did not respond to requests to finalize their article for publication in the journal as the Version of Record.

Preparation of polyethylene elastomers with increased high molecular weight and nearly perfect strain recovery by steric control of asymmetric α-diimine nickel catalyst

The use of α-diimine nickel catalysts to prepare high molecular weight branched polyethylene has matured, but few work reports consider high branch density and ultrahigh molecular weight. Herein, through a combination of asymmetric and steric control strategies, series of catalysts with a gradual increase number of N-aryl ortho-benzhydryl substituent were prepared. Through the analysis of polymerization results, it is believed that large steric hindrance plays a significant role in improving the catalyst thermal stability and reducing the temperature sensitivity of the product branch density and molecular weight. Surprisingly, Ni4, which has three large benzhydryl groups and one small methyl group at the four sites of the N-aryl ortho-position, has high chain growth rate and strong chain walking ability, allows it to prepare highly branched polyethylene with ultra-high molecular weight at higher temperatures with high activity. Moreover, this type of polyethylene material exhibits excellent strain recovery capabilities (98.2 %).

Insights into dynamic evolution of glucuronofucogalactoglucan from water extract of Agrocybe cylindracea during maturation

This study explored the physicochemical properties and structural characteristics of Agrocybe cylindracea polysaccharides at four developmental stages, as well as their dynamic evolution during maturation. Results showed that the polysaccharides from A. cylindracea water extract exhibited similar structural characteristics across all four maturity stages, despite a significant reduction in yields. Four water-soluble heteroglycans, including one high molecular weight (ACPM-Et50-I) and three low molecular weight (ACPM-Et50-II, ACPM-Et60, ACPM-Et80), were isolated from A. cylindracea at each maturity stage. ACPM-Et50-I was identified as branched heterogalactans, while ACPM-Et60 and ACPM-Et80 were branched heteroglucans. However, ACPM-Et50-II was characterized as a branched glucuronofucogalactoglucan at the tide-turning stage but a glucuronofucoglucogalactan at the pileus expansion stage due to the increase of its α-(1 → 6)-D-Galp. In general, although the structural skeletons of most A. cylindracea heteroglycans were similar during maturation as shown by their highly consistent glycosyl linkages, there were still differences in the distribution of some heteroglucans. This work has for the first time reported a glucuronofucogalactoglucan in A. cylindracea and its dynamic evolution during maturation, which may facilitate the potential application of A. cylindracea in food and biomedicine industries.

Metal-organic framework-based porous liquids via surface functionalization engineering for selective gas adsorption

Porous liquids (PLs) combine the distinct porosity of solids with the fluidity of liquids, offering new solutions for carbon capture, membrane separation, and more. This study introduces the development of unique UIO-66-PLs through a meticulous surface functionalization strategy, using surface-modified UIO-66-(OH)2 with the organic oligomer SIT8378.3 (SIT) and polyether amines (PEAs) of various molecular weights (M1000, M2070, and M3085) as the hindering solvents. The resulting UIO-66-PLs exhibit exceptional stability and dispersibility in both aqueous and organic environments. Importantly, benefiting from preserving UIO-66-(OH)2′s porosity in PLs, the affinity of PEAs’ ethylene oxide segments for CO2 via Lewis acid-base interactions, and additional free space within organic chains, UIO-66-PLs revealed enhanced CO2 adsorption capabilities, particularly for CO2 over N2. Encouragingly, CO2 adsorption of UIO-66-PLs was enhanced by 117.54 % (UIO-66-M1000), 106.01 % (UIO-66-M2070), and 22.45 % (UIO-66-M3085) in capacity relative to the respective pure organic outer layer. It is also observed that while surface engineering improves gas adsorption performance, PEAs with a high molecular weight may partially block UIO-66-(OH)2 pores, decreasing gas adsorption capacities. Our research showcases the potential of UIO-66-PLs in gas storage and separation applications, offering a new approach to developing materials functionalized with customized organic molecular weights for advanced CO2 capture technologies.

Immunohistochemical study of mixing mineral trioxide aggregate with hyaluronic acid as a pulp-capping agent in dog teeth

Objective: The purpose of this study was to evaluate the immunohistochemical effect of hyaluronic acid (HA) on the mineralization rate of the reparative dentin when it is used as a mixing medium with mineral trioxide aggregate (MTA). Materials and Methods: Direct pulp capping (DPC) was performed on 90 teeth from 10 dogs that had been experimentally exposed. The exposed pulps were divided into three groups according to the mixing medium with MTA: Group I: MTA + distilled water (control group), Group II: MTA + hybrid cooperative complex HA (HCC-HA), Group III: MTA + high molecular weight HA (HMW-HA). After pulp capping, all cavities were restored with final restoration. The dogs were divided randomly into five groups (two dogs each) according to the evaluation periods (7, 14, 21, 30, and 60) days. At the end of the study, the dogs were euthanized, and the sampled teeth were processed for immunohistochemical investigation. Results: Both types of HA (HCC-HA, HMW-HA) showed an increase in the expression of alkaline phosphatase (ALP) at a higher rate than using distilled water with MTA. Conclusions: Within the limitations of this study, HA proved to be an effective additive to MTA for DPC.

Green conversion of carbon disulfide to degradable polydithiourethanes through catalyst-free multicomponent polymerizations of diamines, carbon disulfide and diacrylates

In the pursuit of advanced functional polymer materials, sulfur-containing polymers have received tremendous attention owing to their superior chemical stability, high refractive indices, various supramolecular interactions, and robust dynamic covalent chemistry. However, their synthesis usually involves either expensive monomers or toxic byproducts and requires catalysts, thus hindering their widespread application. In this work, we present a catalyst-free multicomponent polymerization in organic solvents for the synthesis of various polydithiourethanes with excellent yields (up to 98 %) and high molecular weights (up to 112 kg/mol). This reaction involves the direct polymerization of carbon disulfide, an abundant one-carbon feedstock, with commercially available diamines and diacrylates. This polyaddition process demonstrates high atom economy and no byproduct, occurring at room temperature without the need for a catalyst, thus exhibiting excellent green chemistry metrics. By utilizing the dynamic covalent chemistry of dithiourethane groups, these polymers can be efficiently degraded via aminolysis and used to fabricate reprocessable vitrimers. This multicomponent polymerization opens up a new avenue for the efficient utilization of carbon disulfide resources and accelerates the exploration of diversified sulfur-containing functional polymer materials.

Interfacial rheological properties of pepsin-hydrolyzed lentil protein isolate at oil-water interfaces

Lentil protein isolate (LPI) was investigated for its potential as a plant protein-based emulsifier. LPI consists mainly of globulins with high molecular weights which are relatively slow to adsorb and stabilize oil-water interfaces. Smaller proteins, such as whey protein, can stabilize the interface much faster, quickly forming a viscoelastic film that slows down the rate of droplet recoalescence, leading to smaller droplets. To increase the rate of adsorption, LPI was enzymatically hydrolyzed by pepsin at 1.5% and 4.5% degree of hydrolysis (DH), to obtain small peptides. The behavior of these peptides was studied at the oil-water interface in comparison to whey protein isolate (WPI) and native lentil protein isolate (LPI). Interfacial properties were investigated using dilatational and interfacial shear rheology in the linear viscoelastic regime (LVE) and nonlinear viscoelastic regime (NLVE) and these were related to protein characteristics and emulsion formation. The 1.5% and 4.5%DH LPI showed high surface hydrophobicity, and consisted mainly of low molecular weight peptides, which contributed to faster adsorption kinetics and consequently covered the interface faster than LPI. In dilatation, the native and hydrolyzed LPI-stabilized interfaces had comparable stiffness and were clearly weaker than WPI-stabilized interfaces, which contrasts with the results in shear deformations, where the former both had higher stiffness than WPI. Both hydrolyzed LPI and WPI formed more brittle and less stretchable interfaces compared to native LPI in both dilatational and shear rheology. In emulsification tests, native LPI produces the largest droplets, and the 4.5% DH LPI and WPI have the smallest droplet size. But, bridging flocculation was observed when emulsions were prepared with both hydrolyzed LPI, which may be attributed to inter-droplet hydrophobic interactions between small polypeptides. This can be linked to an increase in the surface hydrophobicity of hydrolyzed LPI. Thus, the use of native LPI as a stabilizer in emulsion preparation is preferable over the hydrolyzed samples, despite its larger droplet size.

Deasphalting of crude oils: a molecule-based model to explore an optimization approach and alternative solvents

Actual motivation to reduce environmental impact leads to an increase in the study of green technologies, even those used in processes with fossil fuels. However, far from the proposed reduction of such energies, heavier crude oils are being processed to fulfill the energy demand. Heavy crude oils require an upgrading process to mitigate the effect of noxious components or contaminants such as asphaltenes and heavy metals. In this work, a deasphalting process was studied by simulation as a pretreatment to eliminate the heavy compounds of crude oil. The simulation of such a deasphalting process was carried out by Aspen Plus® software by combining a model for crude oil, formed by 33 molecules and able to describe its complex composition, mainly in the asphaltene fraction, and a model for the phase equilibria that use liquid-liquid equilibrium equations and the modified UNIFAC (Dortmund) model.A new objective function, including extraction yield, asphaltene reduction, and the ratio solvent/crude oil, was proposed and used to optimize extraction conditions and compare the performance of several solvents. Up to 12 pure solvents of different nature (tert-butanol, n-butanol, iso-propanol, methanol, ethylene glycol, acetone, methyl-isobutyl ketone, per-fluoro heptane, anisole, 1-metil-2-pyrrolidone, sulfolane, and n-heptane) were checked as well as some binary mixtures of them to explore more sustainable alternatives against conventional paraffin as precipitating agents. Satisfactory results were obtained when alcohols or ketones were used. A deeper study was developed to understand the effects of the alcohols' molecular structure (branching, chain length, and molecular weight) as solvents. Higher branching reduces the solvent/oil ratio, while higher molecular weight leads to higher extraction yield but poorer asphaltene reduction.