To fully leverage the advantages of ionic liquids for many applications, it is necessary to immobilize or encapsulate the fluids within an inert, robust, quasi-solid-state format that does not disrupt their many desirable, inherent features. The formation of ionogels represents a promising approach; however, many earlier approaches suffer from solvent/matrix incompatibility, optical opacity, embrittlement, matrix-limited thermal stability, and/or inadequate ionic liquid loading. We offer a solution to these limitations by demonstrating a straightforward and effective strategy toward flexible and durable ionogels comprising bacterial cellulose supports hosting in excess of 99% ionic liquid by total weight. Termed bacterial cellulose ionogels (BCIGs), these gels are prepared using a facile solvent-exchange process equally amenable to water-miscible and water-immiscible ionic liquids. A suite of characterization tools were used to study the preliminary (thermo)physical and structural properties of BCIGs, including no-deuterium nuclear magnetic resonance, differential scanning calorimetry, thermogravimetric analysis, scanning electron microscopy, and X-ray diffraction. Our analyses reveal that the weblike structure and high crystallinity of the host bacterial cellulose microfibrils are retained within the BCIG. Notably, not only can BCIGs be tailored in terms of shape, thickness, and choice of ionic liquid, they can also be designed to host virtually any desired active, functional species, including fluorescent probes, nanoparticles (e.g., quantum dots, carbon nanotubes), and gas-capture reagents. In this paper, we also present results for fluorescent designer BCIG chemosensor films responsive to ammonia or hydrogen sulfide vapors on the basis of incorporating selective fluorogenic probes within the ionogels. Additionally, a thermometric BCIG hosting the excimer-forming fluorophore 1,3-bis(1-pyrenyl)propane was devised which exhibited a ratiometric (two-color) fluorescence output that responded precisely to changes in local temperature. The ionogel approach introduced here is simple and has broad generality, offering intriguing potential in (bio)analytical sensing, catalysis, membrane separations, electrochemistry, energy storage devices, and flexible electronics and displays.
We describe a straightforward tactic to boost the inherently low peroxidase-like activity of the heme-protein equine cytochrome c following its electrostatic assembly onto the carbon nanodot surface.
A deep eutectic solvent (DES) entrapped in a bacterial cellulose (BC) network gives rise to a gelatin-like, selfsupported material termed a bacterial cellulose eutectogel (BCEG).Although this novel material holds potential for numerous industrial, environmental, energy, or medical applications, little is known about the structural features or dynamical behavior within a eutectogel. In this work, we employ X-ray diffraction (XRD), nuclear magnetic resonance (NMR), and small-angle neutron scattering (SANS) to probe the structural and diffusive behavior of the prevailing DES glyceline (1:2 molar ratio of choline chloride:glycerol) confined within bacterial cellulose. XRD investigations demonstrate that the bacterial cellulose maintains its crystallinity even as the glyceline content approaches 95 wt % in the BCEG, an outcome corroborated by molecular dynamics (MD) simulations, which suggest minimal changes in the structural features of the cellulose chains due to the presence of glyceline. SANS measurements reveal a significant reduction in the radius of gyration (R g ) for BC in a BCEG compared to its hydrogel analogue, indicating a collapse in the microfibrillar structure that we attribute to removal of waters from the interfibrillar space due to a higher affinity of DES for water than for cellulose. Furthermore, SANS experiments suggest that the vast majority of DES is hosted within large micropores in the BCEG (i.e., mesoscopic confinement). Interestingly, proton NMR experiments disclose faster diffusional rates for choline and glycerol entrapped in a BCEG compared to neat glyceline. MD simulations offer the possible explanation that this diffusional acceleration results from significant migration of chloride from the bulk to cellulose microfibrillar surfaces, thereby reducing hydrogen bonding with choline and glycerol partners. This study provides the first comprehensive investigation into the structure and diffusional dynamics of glyceline within a eutectogel, offering insights into mass transport that should be useful for tailoring these novel materials to potential applications.
Bacterial cellulose ionogels (BCIGs) represent a new class of material comprising a significant content of entrapped ionic liquid (IL) within a porous network formed from crystalline cellulose microfibrils. BCIGs suggest unique opportunities in separations, optically active materials, solid electrolytes, and drug delivery due to the fact that they can contain as much as 99% of an IL phase by weight, coupled with an inherent flexibility, high optical transparency, and the ability to control ionogel cross-sectional shape and size. To allow for the tailoring of BCIGs for a multitude of applications, it is necessary to better understand the underlying principles of the mesoscopic confinement within these ionogels. Toward this, we present a study of the structural, relaxation, and diffusional properties of the ILs, 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([emim][Tf2N]) and 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ([bmpy][Tf2N]), using 1H and 19F NMR T1 relaxation times, rotational correlation times, and diffusion ordered spectroscopy (DOSY) diffusion coefficients, accompanied by molecular dynamics (MD) simulations. We observed that the cation methyl groups in both ILs were primary points of interaction with the cellulose chains and, while the pore size in cellulose is rather large, [emim]+ diffusion was slowed by ∼2-fold, whereas [Tf2N]− diffusion was unencumbered by incorporation in the ionogel. While MD simulations of [bmpy][Tf2N] confinement at the interface showed a diffusion coefficient decrease roughly 3-fold compared to the bulk liquid, DOSY measurements did not reveal any significant changes in diffusion. This suggests that the [bmpy][Tf2N] alkyl chains dominate diffusion through formation of apolar domains. This is in contrast to [emim][Tf2N] where delocalized charge appears to preclude apolar domain formation, allowing interfacial effects to be manifested at a longer range in [emim][Tf2N].
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Introduction/Objective Primary Pancreatic signet-ring cell carcinoma (PPSRCC) is an extremely rare histologic variant with sparse literature. Herein, we describe a case of PPSRCC in a 75-year-old female with positive family history of pancreatic cancer (47y/o brother). The diagnosis was delayed secondary to diagnostic challenges on initial fine-needle aspiration (FNA). Methods/Case Report Diagnosing PPSRCC on FNA can be extremely difficult. Primary, and metastatic neoplasms to the pancreas may exhibit cytomorphological similarities to signet-ring cells, posing diagnostic challenges. Further, sampling of abundant background inflammatory cells during a biopsy can result in incorrect diagnosis of pancreatitis. Given the strong clinical suspicion based on imaging findings, a second FNA was performed which showed few atypical cells suspicious for carcinoma. Subsequently, the patient underwent neoadjuvant chemotherapy and Whipple resection. The tumor morphology is characterized by infiltrating cells with large mucin vacuoles and peripheric nucleus comprising > 50% of the mass lesion with perineural invasion, in a background of chronic inflammation and pancreatic intraepithelial neoplasia, grade III. A diagnosis of PPSRCC was rendered. Notably, lymph nodes (LN) showed no evidence of metastasis. Results (if a Case Study enter NA) NA. Conclusion Based on limited literature, PPSRCC is considered an aggressive malignancy with low survival rate, because of a high rate of metastasis. However, our case was rather unique given the lack of LN metastasis and the neodjuvant treatment strategy. As of February 2022, <10 cases have been reported with ill-defined characteristics and treatment guidelines.
Introduction/Objective Ampullary cancer (AC) are rare and represents only 6% of the malignant periampullary tumors. Two main histologic subtypes of AC are pancreatobiliary (Pb-AC), and intestinal (In-AC). The data on the influencing role of several characteristics associated with AC subtypes on long term outcome is still emerging. Our study aimed to analyze the two subtypes Pb-AC and In-AC regarding their primary tumor site, median overall survival, and associated precursor lesion. Methods/Case Report Using the cBioPortal platform and systematic bioinformatical analysis of the Cancer Genome Atlas Baylor College of Medicine Cell Reports, 2016, 133 AC patients were included and analyzed based on their morphology subtype. Of which 62 patients had the intestinal subtype, and 71 had the pancreaticobiliary morphological subtype. Results (if a Case Study enter NA) The role of primary tumor site was statistically significant (p-value = 0.01) among subtypes Pb-AC and In-AC (See Figure). Remarkably, the primary tumor site most associated with the pancreaticobiliary subtype was the distal bile duct, and the intestinal subtype was intra-ampullary. Additionally, the precursor lesion identification (absent vs present) was statistically significant among the subtypes (p-value = 0.01). Further, the median overall survival in ampullary carcinoma varied among the morphology of the two subtypes: In-AC (75.56 months, (95% CI: 57.04-NA)) and Pb-AC (27.04 months, (95% CI: 18.29-NA)). Conclusion The findings in this study highlight the complex multifactorial role of the two morphological subtypes in AC. Further studies are essential for understanding the underlying tumor site specific molecular signatures leading to subtyping and their impact on prognosis.
[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI--COLUMBIA AT REQUEST OF AUTHOR.] Pollutants have become more prevalent in the air, water, and ground, necessitating the development of technologies that would help, limit, reverse, monitor, measure, and recycle prevalent pollutants. Ionic liquids (ILs), or molten salts that are liquid at or below 100[degrees]C, as well as deep eutectic solvents (DESs), a mixture of a hydrogen bond donor with a strong hydrogen bond acceptor that remains liquid upon cooling, have been popularized as greener alternatives in industry. These liquids tend to have large electrochemical and thermal windows, a very small vapor pressure, and can be fine-tuned for many applications. The liquid state of ILs and DESs makes them quite useful in their application but complicates their handling. Ionogels and eutectogels enable the liquid-like dynamics of these solvents while adding a pseudo-solid like character that makes for ease of handling. Herein, a new group of confined ILs and DESs within a cellulosic matrix called bacterial cellulose iono/eutecto gels are produced that are shown to be applicable to analyte detection and are studied for a better understanding of the dynamics within the gel. These intriguing gels are flexible, transparent, size-tuneable, shape-tuneable, amenable to incorporation of dyes or other functional material, and capable of confining 99 wt.% of a solvent with little leakage from the gel. These materials affect the crystallinity of cellulose little, while the liquid presents a diffusional change that stems from restructuring of the fluid. These gels are capable of detection of ammonia, hydrogen sulfide, and temperature. Given their properties, iono/eutecto gels offer use in applications, such as electrochemical devices, wound healing, drug delivery, and carbon capture/separation membranes.
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