Molecular Structure Research Articles

Donor–π bridge-acceptor dyes featuring dual chromophoric groups for enhanced sensitivity in wearable sweat sensor

The pH value of human sweat serves as a crucial biomarker for disease diagnosis, rendering wearable sweat sensors an innovative tool for monitoring human health. However, the commercialization of these devices is seriously impeded by their low sensitivity, poor wearing comfort, and limited reusability. In this work, a reactive dye capable of color change under pH change has been synthesized. Due to the unique molecular structure, the dye molecule exhibits remarkable color change recognition and high sensitivity. To fabricate a wearable pH sensor, screen printing technology was employed for depositing the color-changing dye onto cotton fabric. The resulting sensor demonstrated excellent performance attributes including high color sensitivity, robust cyclic stability in response to pH changes, and exceptional resistance against washing, friction, and sunlight-induced fading. Therefore, this study presents a highly promising approach for achieving real-time monitoring of human sweat pH levels.

Strategically Modified Ligand Incorporating Mixed Phosphonate and Carboxylate Groups to Enhance Performance in All‐Iron Redox Flow Batteries

AbstractIron redox flow batteries (Fe‐RFBs) hold significant promise for achieving cost‐effectiveness and utilizing abundant materials for stationary energy storage applications. Here, a design of a novel Fe complex utilizing a nitrogenous phosphonate/carboxylate mixed ligand, N,N‐Bis(phosphonomethyl)glycine (BMPG), is presented to achieve high performance Fe anolyte. Compared to its all‐phosphonate form, nitrilotri(methylphosphonic acid) (NTMPA), the new complex Fe(BPMG)2 demonstrates a negatively shifted redox potential, resulting in ≈0.07 V (≈10%) increase in battery output voltage. Full battery testing paired with ferrocyanide catholyte demonstrates stable cycling (capacity degradation <0.0001%/cycle) over 730 consecutive charge/discharge cycles with Coulombic Efficiency of 100% at a current density of 20 mA cm−2 under near neutral pH (≈8). Of particular interest, density functional theory (DFT) studies and operando Raman measurements provide strong evidence supporting a molecular structure in BPMG, which reveals the mixed phosphonate/carboxylate groups in BPMG maintain the octahedral coordination of the Fe ion center with phosphonates exclusively, while leaving the carboxylate unbound for both Fe(II) and Fe(III) complexes. This structural similarity between BPMG‐based Fe(II) and Fe(III) complexes effectively mitigates the slow redox reaction kinetics observed in Fe(NTMPA)2 anolyte, where significant ligand reorientation occurs between Fe(II) and Fe(III) complexes.

Metal Ion-Condensed DNA Nanoparticle Library: Phase Separation and Transition and Antisense Therapy Applications.

DNA condensation has long been investigated as a fundamental cellular activity and is known to be driven by the mediation of diverse condensing agents. The phase behaviors of DNA during condensation are particularly interesting because the complicated molecular structure of natural nucleotides fundamentally allows electrostatic, coordinate covalent, and various other secondary interactions with the condensing agents. Recently, metal ion (Mn+)-induced DNA condensation has emerged as a powerful approach to synthesizing nanoparticulate DNA structures suitable for therapeutic gene delivery. However, how the DNA phase changes during Mn+-induced DNA condensation has rarely been observed and is not understood yet. In this study, a library of Mn+-condensed DNA nanoparticles (Mn+-CDNPs) was established using 30 different types of Mn+s, and their phase behaviors during condensation were elucidated using spherical nucleic acids (SNAs) as electron microscopic labels. Importantly, the phase transition and separation of DNA were demonstrated to be driven by the Mn+s into either the growth of individual DNA particles or the fission of bulky DNA aggregates. Pt2+ and Eu3+ were chosen as model systems for the demonstration. The hard and soft acid nature of Mn+ is presumably the underlying driving force of these phase transitions. In addition, the Mn+-controlled anticancer therapeutic efficiency of the Mn+-CDNP library as a state-of-the-art gene delivery platform was demonstrated even for unmodified antisense oligonucleotides in association with the potential toxicity of the Mn+s released from the Mn+-CDNPs. This comprehensive study of the Mn+-dependent condensation of nucleic acids provides profound insights into the chemistry of the nucleic acid-Mn+ interactions and the reliable theragnostic applications of Mn+-CDNPs as functional nucleic acid nanostructures.

Elucidation of the influence of trinitro-diazinotriazine isomerism on the energetic properties and stability: Insights from DFT approach

The exploration of isomeric energetic molecules with high nitrogen content and the examination of their structure–property relationships remains compelling areas of interest within the field of energetic materials. Energetic isomers comprising the same molecular composition but distinct molecular structures potentially lead to notable variations in performance and properties. This study focused on designing and evaluating different forms of diazinotriazine using two molecular compositions: C5H3N5 and C5N8O6, aiming to generate various isomeric structures and to guide the rational design of new molecules. The electronic configurations, energetic properties, and sensitivity prediction of the optimized structures were investigated using the M06-2X/def2-TZVPP level of theory. The trinitro-diazinotriazine isomers exhibit high heat of formation (>486 kJ/mol), high detonation properties (D > 8.7 km/s, P > 34 GPa), high density (>1.81 g/cm3), and better thermal stability (BDE > 230 kJ/mol) making them promising explosive contenders. Among the designed diazinotriazine backbones, the pyridazine-1,2,3-triazine framework is favourable for the heat of formation and detonation properties. The heats of formation, detonation velocity, pressure, and heats of detonation of A4 and B4 outperform the other trinitro-diazinotriazine isomers.

High-resolution acoustic ejection mass spectrometry for high-throughput library screening

An approach is described for high-throughput quality assessment of drug candidate libraries using high-resolution acoustic ejection mass spectrometry (AEMS). Sample introduction from 1536-well plates is demonstrated for this application using 2.5 nL acoustically dispensed sample droplets into an Open Port Interface (OPI) with pneumatically assisted electrospray ionization at a rate of one second per sample. Both positive and negative ionization are shown to be essential to extend the compound coverage of this protease inhibitor-focused library. Specialized software for efficiently interpreting this data in 1536-well format is presented. A new high-throughput method for quantifying the concentration of the components (HTQuant) is proposed that neither requires adding an internal standard to each well nor further encumbers the high-throughput workflow. This approach for quantitation requires highly reproducible peak areas, which is shown to be consistent within 4.4 % CV for a 1536-well plate analysis. An approach for troubleshooting the workflow based on the background ion current signal is also presented. The AEMS data is compared to the industry standard LC/PDA/ELSD/MS approach and shows similar coverage but at 180-fold greater throughput. Despite the same ionization process, both methods confirmed the presence of a small percentage of compounds in wells that the other did not. The data for this relatively small, focused library is compared to a larger, more chemically diverse library to indicate that this approach can be more generally applied beyond this single case study. This capability is particularly timely considering the growing implementation of artificial intelligence strategies that require the input of large amounts of high-quality data to formulate predictions relevant to the drug discovery process. The molecular structures of the 872-compound library analyzed here are included to begin the process of correlating molecular structures with ionization efficiency and other parameters as an initial step in this direction.

A Survey on Computational Methods in Drug Discovery for Neurodegenerative Diseases.

Currently, the age structure of the world population is changing due to declining birth rates and increasing life expectancy. As a result, physicians worldwide have to treat an increasing number of age-related diseases, of which neurological disorders represent a significant part. In this context, there is an urgent need to discover new therapeutic approaches to counteract the effects of neurodegeneration on human health, and computational science can be of pivotal importance for more effective neurodrug discovery. The knowledge of the molecular structure of the receptors and other biomolecules involved in neurological pathogenesis facilitates the design of new molecules as potential drugs to be used in the fight against diseases of high social relevance such as dementia, Alzheimer's disease (AD) and Parkinson's disease (PD), to cite only a few. However, the absence of comprehensive guidelines regarding the strengths and weaknesses of alternative approaches creates a fragmented and disconnected field, resulting in missed opportunities to enhance performance and achieve successful applications. This review aims to summarize some of the most innovative strategies based on computational methods used for neurodrug development. In particular, recent applications and the state-of-the-art of molecular docking and artificial intelligence for ligand- and target-based approaches in novel drug design were reviewed, highlighting the crucial role of in silico methods in the context of neurodrug discovery for neurodegenerative diseases.

Biophysical contrast sources for magnetic susceptibility and R2* mapping: A combined 7 Tesla, mass spectrometry and electron paramagnetic resonance study

Iron is the most abundant trace metal in the human brain and consistently shown elevated in prevalent neurological disorders. Because of its paramagnetism, brain iron can be assessed in vivo by quantitative MRI techniques such as R2* mapping and Quantitative Susceptibility Mapping (QSM). While Inductively Coupled Plasma Mass Spectrometry (ICP-MS) has demonstrated good correlations of the total iron content to MRI parameters in gray matter, the relationship to ferritin levels as assessed by Electron Paramagnetic Resonance (EPR) has not been systematically analyzed. Therefore, we included 15 postmortem subjects (age: 26–91 years) which underwent quantitative in-situ MRI at 7 Tesla within a post-mortem interval of 24 h after death. ICP-MS and EPR were used to measure the total iron and ferritin content in 8 selected gray matter (GM) structures and the correlations to R2* and QSM were calculated. We found that R2* and QSM in the iron rich basal ganglia and the red nucleus were highly correlated with iron (R² > 0.7) and ferritin (R² > 0.6), whereas those correlations were lost in cortical regions and the hippocampus. The neuromelanin-rich substantia nigra showed a different behavior with a correlation with total iron only (R² > 0.5) but not with ferritin. Although qualitative results were similar for both qMRI techniques the observed correlation was always stronger for QSM than R2*. This study demonstrated the quantitative correlations between R2*, QSM, total iron and ferritin levels in an in-situ MRI setup and therefore aids to understand how molecular forms of iron are responsible for MRI contrast generation.

Intrinsic Narrowband Blue Phosphorescent Materials and Their Applications in 3D Printed Self-monitoring Microfluidic Chips.

Organic room-temperature phosphorescent (RTP) materials, especially with narrowband emission properties, exhibit great potential for applications in display and sensing, but have been seldom reported. Herein, a rare example of the intrinsic narrowband blue RTP material is fabricated and reported. A series of indolo[3,2,1-kl]phenothiazine derivatives, named Cphpz, 1O-Cphpz, and 2O-Cphpz, are designed and synthesized. Due to their relatively rigid structures, these three compounds showed deep blue narrowband emissions ranging from 396 to 434nm with the full width at half maximum (FWHM) of 31, 26, and 31nm, respectively. To the delight, compound 2O-Cphpz displayed intrinsic narrowband blue RTP at 448 nm with FWHM of 36 nm and a long-lived lifetime of 1.08 s in hydroxyethyl acrylate and acrylic acid matrix. Photophysical studies, single crystal analyses, and TD-DFT calculations are performed to elucidate further the relationships between molecular structures and the narrowband blue RTP properties. Meanwhile, because the narrowband blue RTP is highly sensitive to humidity, a visualizing droplet path optical microfluidic chip is efficiently fabricated through the digital light processing 3D printing.This work provides a rare example and a reliable strategy to realize narrowband blue RTP and further expand their applications in self-monitoring 3D printed structures.

Molecular Structure and Properties of Resistant Dextrins from Potato Starch Prepared by Microwave Heating.

The dextrinization of potato starch was performed using a sophisticated single-mode microwave reactor with temperature and pressure control using 10 cycles of heating with stirring between cycles. Microwave power from 150 to 250 W, a cycle time from 15 to 25 s, and two types of vessels with different internal diameters (12 and 24 mm) and therefore different thicknesses of the heated starch layer were used in order to estimate the impact of vessel size used for microwave dextrinization. The characteristics of resistant dextrins (RD) including solubility in water, total dietary fiber (TDF) content, color parameters, the share of various glycosidic bonds, and pasting and rheological properties were carried out. The applied conditions allowed us to obtain RDs with water solubility up to 74% at 20 °C, as well as TDF content up to 47%, with a predominance of low-molecular-weight soluble fiber fraction, with increased content of non-starch glycosidic bonds, negligible viscosity, and a slightly beige color. The geometry of the reaction vessel influenced the properties of dextrins obtained under the same heating power, time, and repetition amounts. Among the conditions used, the most favorable conditions were heating 10 times for 20 s at 200 W in a 10 mL vessel and the least favorable were 15 s cycles.

Precise Preparation of Supramolecular Spherical Nucleic Acids for Nucleolin-Targeted Gene Delivery.

Molecular spherical nucleic acids (m-SNAs) are a second generation of spherical nucleic acids (SNAs), which are of significance in potential application of targeted delivery of nucleic acids or gene regulation due to their defined molecular structures. Nevertheless, m-SNAs typically involve a single DNA sequence which greatly limits its functions as either targeting purpose or gene regulation. In response, we proposed here a third generation, supramolecular spherical nucleic acids (Supra-SNAs) with two different sequences to achieve both above-mentioned functions. Specifically, we constructed a series of supramolecular self-assembly structures by coupling a cell membrane receptor (i.e., nucleolin)-recognizing aptamer (AS1411)-modified adamantine as targeting probe and human epithelial growth factor receptor 2 (HER2) antisense-functionalized β-cyclodextrin to specifically inhibit the overexpression of HER2 proteins for gene regulations. In comparison to the m-SNA precursors, such Supra-SNA structures exhibited enhanced levels of resistance to nuclease degradation, cellular uptake, gene regulation capabilities and tumor retention capacity. We demonstrated that Supra-SNAs exhibited optimal cell suppression rates and cell apoptosis via a phosphatidylinositol 3-kinase/protein kinase B signaling pathway. The well-defined molecular structures provide an attractive platform for investigating interrelationship between structure and property at the molecular level.

Precise Preparation of Supramolecular Spherical Nucleic Acids for Nucleolin‐Targeted Gene Delivery

AbstractMolecular spherical nucleic acids (m‐SNAs) are a second generation of spherical nucleic acids (SNAs), which are of significance in potential application of targeted delivery of nucleic acids or gene regulation due to their defined molecular structures. Nevertheless, m‐SNAs typically involve a single DNA sequence which greatly limits its functions as either targeting purpose or gene regulation. In response, we proposed here a third generation, supramolecular spherical nucleic acids (Supra‐SNAs) with two different sequences to achieve both above‐mentioned functions. Specifically, we constructed a series of supramolecular self‐assembly structures by coupling a cell membrane receptor (i.e., nucleolin)‐recognizing aptamer (AS1411)‐modified adamantine as targeting probe and human epithelial growth factor receptor 2 (HER2) antisense‐functionalized β‐cyclodextrin to specifically inhibit the overexpression of HER2 proteins for gene regulations. In comparison to the m‐SNA precursors, such Supra‐SNA structures exhibited enhanced levels of resistance to nuclease degradation, cellular uptake, gene regulation capabilities and tumor retention capacity. We demonstrated that Supra‐SNAs exhibited optimal cell suppression rates and cell apoptosis via a phosphatidylinositol 3‐kinase/protein kinase B signaling pathway. The well‐defined molecular structures provide an attractive platform for investigating interrelationship between structure and property at the molecular level.

Innovative Materials for Lamination Encapsulation in Perovskite Solar Cells

AbstractPerovskite solar cells (PSCs), as the forefront of third‐generation solar technology, are distinguished by their cost‐effectiveness, high photovoltaic efficiency, and the flexibility of their bandgap tunability, positioning them as formidable contenders in the photovoltaic market. However, the stability of PSCs remains a significant barrier to their widespread commercialization. Lamination encapsulation is identified as a pivotal intervention to enhance the durability of PSCs under external environmental stress. This review initiates with an in‐depth exploration of the degradation phenomena in PSCs, triggered by environmental stressors such as water, oxygen, light, and heat. This analysis lays bare the degradation mechanisms, thereby highlighting the specific demands for effective encapsulation materials. Subsequently, the review presents a systematic discourse on the latest developments in encapsulation materials, dissecting their molecular structures and linking these to their physical properties and performance in encapsulation applications. The narrative concludes by charting potential future research pathways intended to refine and enhance the encapsulation performance of PSCs, offering several routes for overcoming current limitations and propelling PSCs toward their full commercial potential.

Mechanistic Study on the Optimization of Asphalt-Based Material Properties by Physicochemical Interaction and Synergistic Modification of Molecular Structure

In order to investigate the relationship between the molecular structure of fibers and the differences in physicochemical interactions between fibers and asphalt on the performance of fiber-modified asphalt, this paper chose two types of fibers with different chemical structures: straw fiber and polyester fiber. First, the differences in molecular interactions between the two fibers and asphalt were explored using molecular dynamics, then the differences in the adsorption capacity of the two fibers on asphalt components were tested by attenuated total reflection infrared spectroscopy experiments, and finally, the differences in the rheological properties of the two fiber-modified asphalts were tested by dynamic shear rheology and low-temperature creep experiments. The molecular dynamics simulation findings reveal that polyester fibers may intersperse into asphalt molecules and interact with them via structures such as aromatic rings, whereas straw fibers are merely adsorbed on the asphalt’s surface. Straw fibers and asphalt exhibit hydrogen bonding, whereas polyester fibers and asphalt display van der Waals interactions. The results of attenuated total reflectance infrared spectroscopy indicated that polyester fiber absorbed asphalt components better than straw fiber. The rheological tests revealed that the polyester fiber had the highest complex shear modulus in the temperature range of 46–82 °C, and at 64 °C, the phase angle was 4.289° lower than that of the straw fiber-treated bitumen. Polyester fiber-modified asphalt had a 32.48%, 15.72%, and 6.09% lower creep modulus than straw fiber-modified asphalt at three low-temperature conditions: −6 °C, −12 °C, and −18 °C. It is clear that fibers with aromatic rings as a chemical structure outperform lignin-based fibers in terms of improving asphalt characteristics. The research findings can serve as a theoretical foundation for the selection of fibers to produce fiber-modified asphalt.

Novel troponin fragmentation assay to discriminate between Takotsubo syndrome and acute myocardial infarction.

Cardiac troponin levels are elevated in Takotsubo syndrome (TTS) with significant overlap to acute myocardial infarction (MI). Long and intact cardiac troponin T (cTnT) forms are typical for MI. This study sought to assess whether the fragmentation composition of cTnT release in TTS differs from MI. The concentration of long molecular forms of cTnT (long cTnT) was measured with a novel upconversion luminescence immunoassay and total cTnT with a commercial high-sensitivity cTnT assay in 24 TTS patients and in 84 Type 1 MI patients. The ratio of long to total cTnT (troponin ratio) was determined as a measure of cTnT fragmentation. Troponin ratio was lower in TTS patients 0.13 [0.10-0.20] vs. 0.62 [0.29-0.96], p<0.001). In the ROC curve analyses, troponin ratio showed a better predictive power than total cTnT in discriminating TTS and MI patients (AUC 0.869 [CI95% 0.789-0.948)] vs. 0.766 [CI95% 0.677-0.855], p=0.047). When restricting the analysis to patients with total cTnT below 1200 ng/L (maximal value in TTS patients), the respective AUC values for total cTnT and troponin ratio were 0.599 (CI 95% 0.465-0.732) and 0.816 (CI95% 0.712-0.921), p =0.003). At a cutoff point of 0.12, troponin ratio correctly identified 95% of MI patients and 50% of TTS patients. In contrast to Type 1 MI, only a small fraction of circulating cTnT in TTS exists in intact or long molecular forms. This clear difference in troponin composition could be of diagnostic value when evaluating patients with cTnT elevations and suspicion of TTS. URL: https://www.clinicaltrials.gov; Unique identifier: NCT04465591.

Sr4Os3O12 – A Layered Osmate(V,VI) that is Magnetic Close to Room Temperature

AbstractBlack crystals of the mixed‐valence osmate(V,VI) Sr4Os3O12 were grown via a gas phase reaction in an evacuated silica tube. The material is attracted to a permanent magnet at room temperature (295±5 K) but loses this property when heated or cooled. In this temperature interval, soft magnetic behavior with vanishing coercivity is observed, but the saturation magnetization is only 0.05 μB per formula unit. Resistivity measurements show that Sr4Os3O12 is a semiconductor with a small band gap of about 0.26 eV at room temperature. X‐ray diffraction on a single‐crystal revealed a rhombohedral structure with the space group R m and lattice parameters ar=554.64(2) pm and cr=2700.1(1) pm at 300(1) K. The compound crystallizes in the La4Ti3O12 structure type and is isostructural to Sr4CoRe2O12. The structure is a rhombohedral stack of layered blocks, each of which can be considered as a section of three layers of the cubic perovskite structure cut perpendicular to one of its threefold axes. The Os–O−Os bond angle of about 175° favors superexchange that leads to antiferromagnetic coupling between the osmium atoms with 5d3 and 5d2 configurations. Sr4Os3O12 exhibits strong lattice dynamics. One aspect is the antiferro‐rotative lattice modes of the corner‐sharing [OsO6] octahedra, which freeze upon cooling. At 100 K, an ordered, yet twinned triclinic superstructure is formed. Strong spin‐orbit coupling and other effects cause deformations of the [OsO6] octahedra that differ significantly at 300 K and 100 K, suggesting a change in the electronic configuration. Competing ground states could also explain the temperature‐dependent band gap and the magnetic fluctuations manifested in the magnetization peak at room temperature.

Microscopic view on the polarization-resolved S-SHG intensity of the vapor/liquid interface of pure water.

Second harmonic generation (SHG) is a nonlinear optical phenomenon where two photons at the frequency ω combine to form a single photon at the second-harmonic frequency 2ω. Since that second-order process is very weak in bulk isotropic media, optical SHG responses of interfaces provide a powerful and versatile technique to probe the molecular structure and dynamics of liquid interfaces. Both local dipole contributions and non-local quadrupole contributions can be interesting to investigate different properties of the interface, such as the molecular orientation or the charge density. However, a major difficulty is to comprehend the link between the S-SHG intensity and molecular details. This article reports a numerical approach to model the polarization-resolved SHG intensities of a model vapor/liquid interface of pure water. The influence of the interfacial local environment on the hyperpolarizability is taken into account using quantum mechanical/molecular mechanics calculations. The numerical predictions are in very good agreement with experiments. We detail the hypotheses made during the modeling steps and discuss the impact of various factors on the modeled SHG intensities, including the description of the exciting field in the interfacial layer, the effect of neighboring molecules on the second-harmonic polarization, and the presence of an additional static electric field at the interface.

Three bioactive compounds from Huangqin decoction ameliorate Irinotecan-induced diarrhea via dual-targeting of Escherichia coli and bacterial β-glucuronidase

Irinotecan (CPT-11) is a commonly prescribed chemotherapeutic for the treatment of colon cancer. Unfortunately, acute and delayed diarrhea are prominent side effects of CPT-11 use, and this limits its therapeutic potential. The curative effect of Huangqin decoction (HQD) on chemotherapy-induced diarrhea has been proven. This study investigated the efficacy of the components of HQD (baicalein, baicalin, and paeoniflorin) on CPT-11-induced diarrhea and their underlying mechanisms. Baicalein was found to be the most effective component in improving CPT-11-induced enterotoxicity by intestinal permeability test, ELISA, fluorescence co-localization, and IHC. The combination of baicalin, baicalin and paeoniflorin can obtain similar therapeutic effect to that of HQD. Mendelian randomization analysis, 16 s rRNA sequencing, and fluorescence imaging revealed that baicalein and baicalin significantly inhibited β-glucuronidase (β-GUS) activity. Bacterial abundance analysis and scanning electron microscopy showed that baicalein inhibited the proliferation of Escherichia coli by destroying its cell wall. The molecular dynamics and site-directed mutagenesis results revealed the structural basis for the inhibition of β-GUS by baicalein and baicalin. The results above provide a new idea for the development of drug therapy for adjuvant chemotherapy and theoretical guidance for the optimization of molecular structure targeting β-GUS.Graphical

Glucoconjugated Dinuclear Copper(II) Complex: An Efficient Catalyst for Stereoselective Synthesis of Trisubstituted Propargylamines via Solvent-free A3 Coupling Reaction.

Development of catalytic systems using nontoxic natural precursors is the need of the era, and along this line, we have synthesized a new D-glucose derived ligand (4,6-O-ethylidene-N-(2-hydroxy-4-(octyloxy)benzylidene)-β-D-glucopyranosylamine) and its dinuclear copper(II) complex. The molecular structure of the complex has been established by single-crystal X-ray diffraction studies and detailed noncovalent intermolecular interactions present in it have been explored by Hirshfeld surface analysis. Further, the complex has been used as a catalyst in the enantioselective (87-99 % ee) synthesis of propargylamines in good to excellent yield (82-95 %) via aldehyde-amines-alkynes (A3) coupling reaction under solvent-free condition. The formation of aminal intermediate during the reaction has been confirmed by 1H-NMR and single-crystal X-ray diffraction studies. The catalytic system is reusable without any appreciable loss in the enantioselectivity or product yield.

Effects of frying and food items on the physicochemical properties of palm oil obtained from Nigeria

The consumption of palm oil has particularly increased in Nigeria due to increased population, lifestyle changes, and its health benefits. The conversion and recycling of the ever-growing food waste from household and commercial is one of the known cost-effective and sustainable management strategies. This study investigates the effect of processing on the physicochemical properties of palm oil. Neat palm oil (NPO) and waste palm oil (WPO) samples, derived from frying four different Nigerian food items, were analyzed to determine changes in their physicochemical properties. The outcome of the investigation reveals that higher temperature during frying and contamination from different food items weakens the molecular structure of the palm oil thereby reducing the quality and stability of the samples which is expressed by the differences in their physicochemical properties. The density, peroxide value, and carbon, hydrogen, and oxygen (CHO) values of NPO were 886 kg/m3, 9.473 meqO2/kg, and 39.233% while that of the WPO samples vary between 3.989–4.692 kg/m3, 10.858–15.362 meqO2/kg, and 52.346–58.468%, for density, peroxide value, and CHO, respectively. The result of the descriptive statistics shows that in the 1 series, the mean ± standard deviation (SD) [coefficient of variation (CV%)] is 119.76 ± 263.87 (220.33%). Both the SD and CV% are greater than the mean; this is due to the heterogeneous nature of the parameter values in the samples. When subjected to inferential statistical analysis, the results show that the error of prediction of relationship in NPO sample versus WPO samples is just 5.290% whereas the reduction in the error is 94.71%. More collaborative investigations are needed to determine the ease of conversion to biodiesel and the properties of biodiesel produced from WPO used to fry different Nigerian food items.

Molecular Dynamic Simulations of the Physical Properties of Four Ionic Liquids

In this study, the molecular structure models of four ionic liquids were created, the reverse nonequilibrium molecular dynamics simulation (RNEMD) approach was used to predict their densities and viscosities, and their thermal conductivity was simulated using the non-equilibrium molecular dynamic simulation method (NEMD). The calculated results of ionic liquid densities were compared with the data in the literature; most of the variances are around 2.5%, and the maximum relative deviation was less than 6.27%; viscosity values were compared with the experimental data, with a maximum relative deviation of −8.96% and a minimum relative deviation of −2.72%. The simulated thermal conductivity has a good linear relationship with respect to temperature and pressure, which is in good agreement. This study provides a reference for molecular dynamics simulation to measure the physical properties of ionic liquids, which is important for the development of ionic liquids.