Size Of Molecules Research Articles

Abstract 2332: VSTM2A modulation of immune response in colorectal cancer through abrogating PD-L1 and PD-1 interaction

Abstract Background: Checkpoint immunotherapy using humanized antibody is a new therapeutic strategy against advanced colorectal cancer (CRC). Nonetheless, it shows low tumor penetration due to the large molecule size. Therefore, small immune regulatory molecules are actively sought. Our previous study showed that a small secretory protein VSTM2A suppressed Wnt signalling pathway through inducing LRP6 lysosome dependent degradation. However, its role in immune modulation is largely unknown. Methods: Clinicopathological features were analyzed using CRC patient cohort. Functional biology of VSTM2A was investigated using T cell-antigen presenting cell (APC) co-culture models and knockout mice model. Liquid chromatography with tandem mass spectrometry (LC-MS) was carried out for mechanistic investigation. Results: Gene ontology analysis of colon RNA-seq dataset from TCGA/GTEx revealed significant enrichment of adaptive immune response and lymphocyte activation with high VSTM2A expression. CRC patients with inferior VSTM2A expressions were associated with lower immunoscores in both early and late stages of CRC. In addition, our immunohistochemical examinations of 208 in-house CRC cases further pinpoints to a considerable fraction of VSTM2A-negative cases showing avoidance of spontaneous CD8a+ cells infiltration (Pearson's chi-squared test P < 0.001, φ = 0.24) and worse clinical outcome. LC-MS assay followed by reciprocal immunoprecipitation revealed that VSTM2A interacted with the IgV motif of immune checkpoint protein programmed cell death 1 ligand 1 (PD-L1). We further found that VSTM2A recognized PD-L1 with a dissociation constant (Kd) of 2.6 nM. Recombinant VSTM2A dose dependently suppressed the interaction of PD-L1 and PD-1 with IC50 of 4.51 nM, indicating VSTM2A is a potential intrinsic PD-L1 antagonist. Moreover, our in-vitro mechanistic studies revealed that VSTM2A protein could block the interaction of PD-1/PD-L1, and induced NFAT-RE luciferase activity dose-dependently using a bioluminescent cell-based PD-1/PD-L1 blockade bioassay. VSTM2A could dramatically activate the interleukin-2 production from DO11.10 T cell in the presence non-T cell spherocyte isolated from BALB/c mice and OVA323-339 peptide. Furthermore, our in-vivo study revealed that VSTM2A triggered a distinct increase in CD45+CD3+ T cells infiltration in the syngeneic MC38 mouse model. Vstm2a+/- knockout mice challenged with azoxymethane and dextran sodium sulfate showed significantly high CRC incidence and tumor burden in comparison to wild-type littermates. Tumor from Vstm2a+/- mice showed significantly less CD8+ T cell infiltration. Conclusions: our study demonstrate the tumor extrinsic role of VSTM2A in modulation of microenvironment through abrogating PD-L1/PD-1 interaction. Silencing of VSTM2A in CRC could suppress T cell activation and infiltration in the tumor sites. Citation Format: Yujuan Dong, Yunfei Zhou, Nathalie Wong, Jun Yu, Siu Man Simon Ng. VSTM2A modulation of immune response in colorectal cancer through abrogating PD-L1 and PD-1 interaction [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2332.

Mini Review on Polymer-based Nano Enable System for Targeted Delivery of Chalcone Derivatives against Cancerous Tissues: An Effective Treatment Approach

Abstract: Nanotechnology augmentation have enabled the creation of innovative colloidal preparations that can modify the pharmacological characteristics of medications. Numerous effective applications in the treatment of cancer have been made possible by the distinctive physicochemical and technological characteristics of therapies based on nanomaterials. To facilitate and maximize the interaction between cells and tissues, it is necessary to examine and modify the size, shape, charge, and patterning of nanoscale therapeutic molecules. The flavonoids chalcones and their natural scaffolds provide a variety of biological effects crucial for creating medicines. Plant-based anticancer medicines represent a promising scientific and business opportunity that should be investigated. By using traditional Chinese medicine (TCM) therapies, diseases can be avoided, and healthcare can be enhanced. Traditional Chinese medicine is safe, straightforward, and reasonably priced. There are numerous treatments for chronic, geriatric, and incurable diseases. Heterocyclic equivalents of chalcones have a variety of biological properties. One of them is its anti-cancer properties, and as a result Chalcones have drawn a huge interest in the study of malignancy. Licorice is an essential primary ingredient in many traditional folk medicines, including Chinese and Mongolian medicine. Research on chalcone scaffolds with strong growth-inhibitory activity in tumor cell lines was influenced by the rising interest in this medicinal molecule, and numerous papers on these scaffolds are now accessible. It is necessary to do a thorough examination before chalcone congeners can be developed as a prodrug or primary chemical to treat cancer. To create a focused and efficient drug delivery system for cancer treatment, we shall discuss chalcone derivatives and their nano-enabled drug delivery systems in this article. It has been discussed how polymeric nanoparticles might effectively localize in particular tumor tissues and act as drug delivery vehicles for anticancer drugs due to their physicochemical characteristics. A promising strategy to increase the effectiveness of various tumor treatments is the nanoencapsulation of anticancer active substances in polymeric systems.

Design of Lead Hybrid Halide Perovskite for Solar Cells

Hybrid organic-inorganic halide perovskites solar cells have attracted extensive interest because of their outstanding properties, including an optimal band gap, high carrier mobility, and excellent optoelectronic merits. We study the electronic and crystal structural properties of hybrid organic-inorganic halide APbX3 (A = Cs, methylammonium (MA), formamidinium (FA), X = I, Br) perovskites using first-principles calculations based on density functional theory. We find that halide atoms and A-site cations strongly affect their structural and electronic properties. The radius of a halide atom and the size of an organic molecule determine their lattice parameters and bond length. A relatively large halide atom can increase the value of the lattice parameters (a and b). Meanwhile, the electronic properties (band gap & carrier effective mass) of the Pb-based hybrid halide APbX3 can be effectively modified by adopting appropriate A- and X-site atoms or organic sections. We predict that HOIPs may have outstanding potential in solar light harvesting with promoted power conversion efficiency due to a tunable band gap and excellent electronic properties.

Size and Charge Effects on Crossover of Flow Battery Reactants Evaluated by Quinone Permeabilities Through Nafion

Organic reactants are promising candidates for long-lifetime redox flow batteries, and synthetic chemistry unlocks a wide design space for new molecules. Minimizing crossover of these molecules through ion exchange membranes is one important design consideration, but the ways in which the crossover rate depends on the structure of the crossing species remain unclear. Here, we contribute a systematic evaluation of size- and charge-based effects on dilute-solution small molecule permeability through the Nafion NR212 cation exchange membrane. We found that increasing the magnitude of charge number z with the same sign as membrane fixed charges, achieved here by successive sulfonation of quinone redox cores, results in more than an order of magnitude permeability reduction per sulfonate. Size-based effects, understood by comparing the Stokes radii of the quinones studied, also reduces permeability with increasing effective molecule size, but doubling the effective size of the redox reactants resulted in a permeability decrease of less than a factor of three.

Mengkaji Kesan Kekonduksian Pengenapan Politiofena / Polipirol /Polianilina (PT /PPY /PANI) di Atas Kaca Indium Timah Oksida (ITO)

The conducting polymer family is widely used in the field of polymer-based sensors. Among the polymers that are often used are polyaniline (PANI), polypyrrole (PPY) and polythiophene (PT). Sensors operate based on the production of signals by analyte molecules which then produce measurements either qualitatively or quantitatively. In addition, the use of conducting polymers in the field of biosensing has highlighted its importance, especially in the fields of biomedicine, environment, food quality control and more. Even so, there are issues that often arise such as controlling and producing signals of the materials used. Appropriate materials and methods also need to be studied. Therefore, this study was conducted to examine the conductivity effect of the deposition of Polythiophene / Polypyrrole / Polyaniline (PPY/ PT/PANI) on Indium Tin Oxide (ITO) Glass. Polyaniline monolayer (PANI) was deposited on the surface of indium tin oxide (ITO) glass using the Langmuir Blodgett (LB) technique. The monolayer surface of PANI particles has been coated with a layer of polypyrrole (PPY) and polythiophene (PT). PPY and PT were dissolved in methanol and then added with p-toluene sulfonic acid (PTSA) to give the same effect as PANI, especially on their back chain structure. The UV-Vis and FTIR spectra prove the existence of peaks resulting from the solubility and doping process against PPY and PT. It was found that the uneven size of the polymer molecules results from the PPY / PANI image because there is a probability that the existing PPY clumps with each other. When PT was applied to the PPY / PANI layer, a combination of the three polymers formed a cavity on the surface of the PT / PPY / PANI layer. It was explained by the analysis of FTIR PT / PPY / PANI which exhibits the existence of bonds between the combined polymers. The material resistance decreases when the three polymers were combined which explains the higher conductivity value obtained.

WS2 and WS2-ZnO Chemiresistive Gas Sensors: The Role of Analyte Charge Asymmetry and Molecular Size.

We investigate the interaction of various analytes (toluene, acetone, ethanol, and water) possessing different structures, bonding, and molecular sizes with a laser-exfoliated WS2 sensing material in a chemiresistive sensor. The sensor showed a clear response to all analytes, which was significantly enhanced by modifying the WS2 surface. This was achieved by creating WS2-ZnO heterojunctions via the deposition of ZnO nanoparticles on the WS2 surface with a high-throughput, atmospheric-pressure spatial atomic layer deposition system. Water and ethanol produced a much higher response compared to acetone and toluene for both the WS2 and WS2-ZnO sensing mediums. We resolved that the charge-asymmetry points in analyte molecules play a key role in determining the sensor response. High charge-asymmetry points correspond to highly polar bonds (HPBs) in a neutral molecule that have a high probability of interaction with the sensing medium. Our results indicate that the polarity of the HPBs primarily dictates the interaction between the analyte and sensing medium and consequently controls the response of the sensor. Moreover, the size of the analyte molecule was found to affect the sensing response; if two molecules have the same HPBs and are exposed to the same sensing medium, the smaller molecule is likely to produce a higher and faster response. Our study provides a comprehensive picture of analyte-sensor interactions that can help in advancing semiconductor gas sensors, including those based on two-dimensional materials.

Study on the effect of physical structure and chemical modification of molecular sieve on the adsorption properties of C4F7N and its decomposition products

The environmentally friendly insulation medium C4F7N mixed gas decomposes after long-term overheating and partial discharge (PD). Some of the decomposition products not only affect the stable operation of gas insulated switchgear but also cause personal safety hazards. Therefore, the adsorption materials need to be equipped for adsorbing decomposition products in the equipment. Molecular sieves are considered to be the most promising adsorbent materials with wide variety and ionic modification space. In order to better apply the molecular sieve to adsorb the decomposition products of C4F7N, the effects of its physical structure and chemical modification on the adsorption of C3F8, C3F6, C2F6, and CF4 are investigated based on Grand Canonical Monte Carlo (GCMC) and Density functional theory (DFT) in this paper. Firstly, the adsorption amounts and sites of various pure silica-type molecular sieves (ATS, BEA, BOG, CAN, CHA, LAU, LTA, MTW, STT, TON, and ZSM) are investigated by GCMC. Then the adsorption energy, charge transfer, and density of states of the molecular sieve modified by cations (H+, Na+, Mn2+, and Fe2+) for C4F7N and its decomposition products are obtained based on DFT. The results reveal that the molecular sieve topology, size of gas molecules and molecular sieve windows are important factors affecting the adsorption process. After modification with Mn2+ and Fe2+, the adsorption energy and electron transfer of C4F7N decomposition products by ZSM molecular sieve increased significantly and the adsorption distance became closer. The main action site of C4F7N is CN bond, the main action sites of C2F6 are CC double bond and F atom, and C3F8, C2F6 and CF4 is F atom.

Are Accelerated and Enhanced Wave Function Methods Accurate to Compute Static Linear and Nonlinear Optical Properties?

Key components of organic-based electro-optic devices are challenging to design or optimize because they exhibit nonlinear optical responses, which are difficult to model or rationalize. Computational chemistry furnishes the tools to investigate extensive collections of molecules in the quest for target compounds. Among the electronic structure methods that provide static nonlinear optical properties (SNLOPs), density functional approximations (DFAs) are often preferred because of their low cost/accuracy ratio. However, the accuracy of the SNLOPs critically depends on the amount of exact exchange and electron correlation included in the DFA, precluding the reliable calculation of many molecular systems. In this scenario, wave function methods such as MP2, CCSD, and CCSD(T) constitute a reliable alternative to compute SNLOPs. Unfortunately, the computational cost of these methods significantly restricts the size of molecules to study, a limitation that hampers the identification of molecules with significant nonlinear optical responses. This paper analyzes various flavors and alternatives to MP2, CCSD, and CCSD(T) methods that either drastically reduce the computational cost or improve their performance but were scarcely and unsystematically employed to compute SNLOPs. In particular, we have tested RI-MP2, RIJK-MP2, RIJCOSX-MP2 (with GridX2 and GridX4 setups), LMP2, SCS-MP2, SOS-MP2, DLPNO-MP2, LNO-CCSD, LNO-CCSD(T), DLPNO-CCSD, DLPNO-CCSD(T0), and DLPNO-CCSD(T1). Our results indicate that all these methods can be safely employed to calculate the dipole moment and the polarizability with average relative errors below 5% with respect to CCSD(T). On the other hand, the calculation of higher-order properties represents a challenge for LNO and DLPNO methods, which present severe numerical instabilities in computing the single-point field-dependent energies. RI-MP2, RIJK-MP2, or RIJCOSX-MP2 are cost-effective methods to compute first and second hyperpolarizabilities with a marginal average error with respect to canonical MP2 (up to 5% for β and up to 11% for γ). More accurate hyperpolarizabilities can be obtained with DLPNO-CCSD(T1); however, this method cannot be employed to obtain reliable second hyperpolarizabilities. These results open the way to obtain accurate nonlinear optical properties at a computational cost that can compete with current DFAs.

Chain-Length Induced Structural Polymorphism for two-dimension self-assembly

Structural polymorphism obtained through the 2D self-assembly which was made use of the chain-ength induced, has has aroused wide concern. On the one hand, owing to its significance meaning in crystal engineering, on the other hand, it has a broad application prospect in nano science and technolog.The assembly of symmetric 2, 7-bis (n-alkoxy) -9-fluorenone(F-OCn) with varying lengths of peripheral alkyl chains dissolved in homologous acids was investigated. The size and shape of molecules and the structure and position of substituents were critical factors that regulate the equilibrium of the interaction and formation of self-assembled patterns. Useing altered the symmetry and chain-length of the molecular structure, the self-assembly morphology and cellular properties can be predicted. The self-assembled strcture displayed the assembly of F-OCn (11-14). “S” shaped and alternating phases are the thermodynamic stable states. The competition between van der Waals forces from the interdigital alkyl chains and van der Waals forces between molecule-substrate takes effect. The vdW forces between the molecule-substrate was predominant when n varies from 15 to 18. The observation of the chain-length effects and odd-even effects showed that: F-OCeven developed from a loose-and close-packed patterns to a dislocated zigzag patterns.Self-assembled morphology of F-OCodd evolved from a well-distributed trimer monolayer to the dislocated zigzag pattern.These researches offers insight into the structural diversity by regulating the alkyl side chain-length and odd-even effects on two-dimension self-assembly and the construct a new molecular materials.

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Description of reaction and vibrational energetics of CO2–NH3 interaction using quantum computing algorithms

CO2 capture is critical to solving global warming. Amine-based solvents are extensively used to chemically absorb CO2. Thus, it is crucial to study the chemical absorption of CO2 by amine-based solvents to better understand and optimize CO2 capture processes. Here, we use quantum computing algorithms to quantify molecular vibrational energies and reaction pathways between CO2 and a simplified amine-based solvent model—NH3. Molecular vibrational properties are important to understanding kinetics of reactions. However, the molecule size correlates with the strength of anharmonicity effect on vibrational properties, which can be challenging to address using classical computing. Quantum computing can help enhance molecular vibrational calculations by including anharmonicity. We implement a variational quantum eigensolver (VQE) algorithm in a quantum simulator to calculate ground state vibrational energies of reactants and products of the CO2 and NH3 reaction. The VQE calculations yield ground vibrational energies of CO2 and NH3 with similar accuracy to classical computing. In the presence of hardware noise, Compact Heuristic for Chemistry (CHC) ansatz with shallower circuit depth performs better than Unitary Vibrational Coupled Cluster. The “Zero Noise Extrapolation” error-mitigation approach in combination with CHC ansatz improves the vibrational calculation accuracy. Excited vibrational states are accessed with quantum equation of motion method for CO2 and NH3. Using quantum Hartree–Fock (HF) embedding algorithm to calculate electronic energies, the corresponding reaction profile compares favorably with Coupled Cluster Singles and Doubles while being more accurate than HF. Our research showcases quantum computing applications in the study of CO2 capture reactions.

Dipole Cooperativity and Polarization Frustration Determine the Secondary Structure Distribution of Short Alanine Peptides in Water.

The physical driving forces for secondary structure preferences of hydrated alanine peptide are investigated with B3LYP-D3(BJ) and the adaptive force matching (AFM) method. The AFM fit to the DFT surface, ALA2022, provides excellent agreement with the nuclear magnetic resonance scalar coupling constants from experiments. In turn, the model is used to gain insight into the physical driving forces behind secondary structure preferences of hydrated peptides. DFT calculations with and without the Conductor-like Screening Model (COSMO) show that the α helix is stabilized by solvent polarization due to dipole cooperativity. The two adjacent amide groups in β strand form a near-planar trapezoid that is not much larger than the size of water molecules. When the finite size of a water molecule is considered, the stabilization from solvent polarization for such a trapezoid is frustrated. Water molecules cannot find orientations to properly stabilize all four polar regions close to each other with such an awkward arrangement. This leads to quite substantial reduction in polarization stabilization. Although the polyproline II (PP-II) conformation is very similar to the β strand, the small twist in the backbone angles allowed much improved polarization stabilization. The improved polarization, when combined with favorable intrapeptide interactions, leads to the PP-II to be lowest in free energy. Other factors, such as the entropic TΔS and the ϕ, ψ coupling terms, are also studied but are found to play only a minor role. The insight shown in this work helps to better understand the structure of globular and intrinsic disordered proteins and facilitate future force field development.

Composition of the Solvation Shell of the Selected Cyclic Ethers (1,4-Dioxane, 12-Crown-4, 15-Crown-5 and 18-Crown-6) in a Mixture of Formamide with Water at Four Temperatures

The solution enthalpy of 15-crown-5 and 18-crown-6 ethers in the mixture of formamide (F) and water (W) was measured at four temperatures: 293.15 K, 298.15 K, 303.15 K, 308.15 K. The standard molar enthalpy of solution, ΔsolHo, depends on the size of cyclic ethers molecules and the temperature. With increasing temperature, the values of ΔsolHo become less negative. The values of the standard partial molar heat capacity Cp,2o of cyclic ethers at 298.15 K have been calculated. The Cp,2o=f(xW) curve shape indicates the hydrophobic hydration process of cyclic ethers in the range of a high-water content in the mixture with formamide. The enthalpic effect of preferential solvation of cyclic ethers was calculated and the effect of temperature on the preferential solvation process was discussed. The process of complex formation between 18C6 molecules and formamide molecules is observed. The cyclic ethers molecules are preferentially solvated by formamide molecules. The mole fraction of formamide in the solvation sphere of cyclic ethers has been calculated.

Zinc Oxide Films Fabricated via Sol-Gel Method and Dip-Coating Technique-Effect of Sol Aging on Optical Properties, Morphology and Photocatalytic Activity.

Zinc oxide layers on soda-lime glass substrates were fabricated using the sol-gel method and the dip-coating technique. Zinc acetate dihydrate was applied as the precursor, while diethanolamine as the stabilizing agent. This study aimed to determine what effect has the duration of the sol aging process on the properties of fabricated ZnO films. Investigations were carried out with the sol that was aged during the period from 2 to 64 days. The sol was studied using the dynamic light scattering method to determine its distribution of molecule size. The properties of ZnO layers were studied using the following methods: scanning electron microscopy, atomic force microscopy, transmission and reflection spectroscopy in the UV-Vis range, and the goniometric method for determination of the water contact angle. Furthermore, photocatalytic properties of ZnO layers were studied by the observation and quantification of the methylene blue dye degradation in an aqueous solution under UV illumination. Our studies showed that ZnO layers have grain structure, and their physical-chemical properties depend on the duration of aging. The strongest photocatalytic activity was observed for layers produced from the sol that was aged over 30 days. These layers have also the greatest porosity (37.1%) and the largest water contact angle (68.53°). Our studies have also shown that there are two absorption bands in studied ZnO layers, and values of optical energy band gaps determined from positions of maxima in reflectance characteristics are equal to those determined using the Tauc method. Optical energy band gaps of the ZnO layer fabricated from the sol aged over 30 days are EgI = 4.485 eV and EgII = 3.300 eV for the first and second bands, respectively. This layer also showed the highest photocatalytic activity, causing the pollution to degrade 79.5% after 120 min of UV irradiation. We believe that ZnO layers presented here, thanks to their attractive photocatalytic properties, may find application in environmental protection for the degradation of organic pollutants.

Prediction models of the ionization coefficient and ionization cross-section based on multi-layer molecular parameters

Prediction models were proposed to estimate the reduced Townsend ionization coefficient and ionization cross-section. A shape function of the reduced Townsend ionization coefficient curves was derived from the ionization collision probability model. The function had three parameters: the first ionization potential energy, A α , and B α . A α and B α were related to the molecule symmetry and size. The polarization of molecules could characterize the molecule symmetry. The multi-layer molecular cross-section (MMCS) was proposed to describe the contributions of electrons and molecule radius on different molecule surfaces to collisions. A prediction model of the ionization cross-section was also proposed based on A α . The molecule parameters were calculated by the Becke3–Lee–Yang–Parr (B3LYP) method and the 6–311G** basis set. We used available data of 30 and 23 gases, respectively, to build the prediction models of reduced Townsend ionization coefficients and ionization cross-sections. The relationships between the molecular parameters A α and B α and the ionization cross-section were built up via nonlinear fittings. The determination coefficients R 2 of A α , B α , and the ionization cross-section were 0.877, 0.887, and 0.838, respectively. The results showed that the accuracy of models was positively correlated with the molecule symmetry and reduced electric field. This was mainly related to the accuracy of the MMCS model in predicting A α . The MMCS model needed to be improved to describe the collision direction selectivity caused by the molecule asymmetry. Under a high reduced electric field, that error of A α had less influence on the prediction results. However, the prediction results for single atoms with high symmetry were poor. This may be due to the absolute error of the model close to single atoms’ reduced Townsend ionization coefficients. The models could provide the basis for gas insulation prediction and discharge calculations, especially for symmetric molecules under a high electric field.

Size selectivity in adsorption of polydisperse starches on activated carbon

The influence of molecular weight, polydispersity, and degree of branching of four potato starches (Paselli MD10, Eliane MD6, Eliane MD2, and highly branched starch) on the adsorption rates on activated carbon (Norit CA1) was investigated. Changes in starch concentration and size distribution over time were analysed by Total Starch Assay and Size Exclusion Chromatography. Average molecular weight and degree of branching of a starch scaled negatively with average adsorption rate. Within a size-distribution, adsorption rates scaled negatively with increasing molecule size, resulting in an increased average molecular weight in solution of between 25 % and 213 % and a decreased polydispersity of between 13 % and 38 %. Simulation with dummy distributions estimated the ratio of adsorption rates for 20th percentile and 80th percentile molecules within a distribution to range between a factor 4 and 8 for the different starches. Competitive adsorption decreased the adsorption rate of molecules above the average size within a sample distribution.

Textile Functionalization by Porous Protein Crystal Conjugation and Guest Molecule Loading

Protein crystals are versatile nanostructured materials that can be readily engineered for applications in nanomedicine and nanobiotechnology. Despite their versatility, the small size of typical individual protein crystals (less than one cubic mm) presents challenges for macroscale applications. One way to overcome this limitation is by immobilizing protein crystals onto larger substrates. Cotton is composed primarily of cellulose, the most common natural fiber in the world, and is routinely used in numerous material applications including textiles, explosives, paper, and bookbinding. Here, two types of protein crystals were conjugated to the cellulosic substrate of cotton fabric using a 1,1′-carbonyldiimidazole/aldehyde mediated coupling protocol. The efficacy of this attachment was assessed via accelerated laundering and quantified by fluorescence imaging. The ability to load guest molecules of varying sizes into the scaffold structure of the conjugated protein crystals was also assessed. This work demonstrates the potential to create multifunctional textiles by incorporating diverse protein crystal scaffolds that can be infused with a multiplicity of useful guest molecules. Cargo molecule loading and release kinetics will depend on the size of the guest molecules as well as the protein crystal solvent channel geometry. Here, we demonstrate the loading of a small molecule dye into the small pores of hen egg white lysozyme crystals and a model enzyme into the 13-nm pores delimited by “CJ” crystals composed of an isoprenoid-binding protein from Campylerbacter jejuni.

Microwave-assisted design of nanoporous graphene membrane for ultrafast and switchable organic solvent nanofiltration

Layered two-dimensional materials can potentially be utilized for organic solvent nanofiltration (OSN) membrane fabrication owing to their precise molecular sieving by the interlayer structure and excellent stability in harsh conditions. Nevertheless, the extensive tortuosity of nanochannels and bulky solvent molecules impede rapid permeability. Herein, nanoporous graphene (NG) with a high density of sp2 carbon domain was synthesized via sequential thermal pore activation of graphene oxide (GO) and microwave-assisted reduction. Due to the smooth sp2 carbon domain surfaces and dense nanopores, the microwave-treated nanoporous graphene membrane exhibited ultrafast organic solvent permeance (e.g., IPA: 2278 LMH/bar) with excellent stability under practical cross-flow conditions. Furthermore, the membrane molecular weight cut-off (MWCO) is switchable from 500 Da size of molecule to sub-nanometer-size molecules depending on the solvent type, and this switching occurs spontaneously with solvent change. These properties indicate feasibility of multiple (both binary and ternary) organic mixture separation using a single membrane. The nanochannel structure effect on solvent transport is also investigated using computation calculations.

Introduction of Multicomponent Dyes into 2D MOFs: A Strategy to Fabricate White Light-Emitting MOF Composite Nanosheets

Metal-organic frameworks (MOFs) have been extensively studied in host-guest chemistry by means of ultrahigh porosities, tunable channels, and component diversities. As the host matrix, MOFs exhibit immense potential in the preparation of single-phase white light-emitting (SPWLE) materials. Nonetheless, it is a great challenge that the size of the introduced guest molecules is limited by MOF pores, which affects the WLE optimization. In this work, two-dimensional (2D) MOFs are first utilized as the host matrices to simultaneously encapsulate red-green-blue fluorescent dyes for SPWLE. Various dyes@2D MOF composites with high-quality WLE performances and ultrathin nanosheet morphologies are directly assembled from 2D MOF precursors and dyes in high yields. Owing to the flexible interlamellar space of 2D MOFs, different types and sizes of guests can be easily introduced, which greatly expands the range of available MOF hosts and guests, making the WLE much more tunable. The strategy of employing 2D MOFs as the host matrices to introduce multicomponent dyes for SPWLE nanosheets resolves the restriction of MOF pores on the guest molecule size and opens a new avenue to rationally design and prepare SPWLE nanosheets that are highly solution-processable.

Tuning the size and concentration of functional molecules coated onto mesoporous silica nanoparticles for efficient therapeutic protein delivery

In this work, the importance of the size and concentration of binding sites in mesoporous nanostructures on their performance for protein delivery is reported. Various types of carboxyl-functionalized mesoporous silica (MS) nanoparticles, i.e., SA(x)-MS, PA1(x)-MS and PA2(x)-MS, where x = 5, 10, 15, 20 and 30 mg, were synthesized by using succinic anhydride (SA) and polyacrylic acid with two molecular weights (i.e., 1800 (PA1) and 100,000 (PA2)), respectively. The particles were thoroughly characterized by TGA, FTIR, STEM and zeta potential measurement techniques and then, their biomedical performance was investigated by using a model therapeutic protein, lysozyme. The carboxyl functional molecules concentration (CCOOH) on the particles was increased as a function of the functional molecules type and quantity in the synthesis reaction environment. The maximum CCOOH values were recorded for SA(10)-MS, PA1(15)-MS and PA2(15)-MS, being 827, 1662 and 2137 µmol.g−1, respectively. However, SA(10)-MS, PA1(15)-MS and PA2(10)-MS particles led to the highest lysozyme loading yield values of 63.1%, 90.0% and 71.5% as well as the loading capacities of 631, 900 and 715 mg.g−1, respectively. The controlled lysozyme release rate and some protein conformational changes favored the in vitro antibacterial activity of lysozyme molecules carried by the particles, which followed the order of PA1(15)-MS > PA2(10)-MS > SA(10)-MS.