Characteristic Peaks Research Articles

Synthesis of Silver Nanoparticles and Evaluation of Antimicrobial Activity Using the Aqueous Extract of Pterodon emarginatus Seeds.

The decline in research for new antimicrobials, combined with the rise in bacterial resistance, has become a critical issue that is expected to worsen over time. As an alternative, health sciences have integrated materials engineering to develop new bioactive compounds through the interaction of nanoparticles with plant-derived compounds. These compounds offer advantages such as high bioavailability and low cost, exemplified byPterodon emarginatus, a plant native to the Brazilian Cerrado. This study aimed to synthesize and stabilize silver nanoparticles (AgNPs) using the aqueous extract ofPterodon emarginatusseeds and evaluate their antimicrobial activity against fungal (Candida albicans) and bacterial (Escherichia coli) strains. The synthesis of AgNPs was performed using the aqueous plant extract as a stabilizing agent, with formation confirmed through UV-Vis spectroscopy, showing a characteristic absorbance peak at 400 nm. The resulting AgNPs were then tested for antimicrobial activity. While the aqueous extract ofP. emarginatusalone showed no significant antimicrobial activity, the synthesized AgNPs demonstrated remarkable antifungal and antibacterial effects. These results highlight the synergistic interaction between the bactericidal properties of AgNPs and the bioactive compounds present in the plant extract. This approach offers a promising and sustainable alternative for the development of new antimicrobial agents, addressing the urgent need for effective solutions to combat microbial resistance.

Catalytic Pyrolysis of Waste Textiles for Hydrogen-Rich Syngas Production over NiO/Al2O3 Catalyst

Hydrogen production through the catalytic pyrolysis of low-value organic solid waste offers a promising low-carbon and environmentally friendly pathway. However, the design of efficient hydrogen-producing catalysts remains a significant challenge. Herein, NiO/Al2O3 as a catalyst precursor was utilized to investigate the effects of reduction temperature gradients (300–800 °C) on the distribution of three-phase products and the composition of gaseous products during the pyrolysis of waste textiles. Compared to unreduced NiO/Al2O3, increasing the reduction temperature (300–700 °C) led to a gradual decrease in liquid-phase products and a notable increase in gas-phase products, with the latter rising by 10.59% at 700 °C. Most strikingly, hydrogen gas production increased by 6.42% under the same conditions. Multi-characterization analyses, including XRD, TEM, and H2-TPR, revealed significant aggregation of highly dispersed Ni species in NiO/Al2O3 at higher reduction temperatures. The emergence of XRD characteristic peaks and the (111) crystal face of metallic Ni (Ni0) became apparent at 700 °C. More importantly, the XPS test inferred that the increasement of hydrogen-rich gas production was ascribed to the appropriate Ni0/Ni2+ ratio, and the highest hydrogen yield of 41.50% was achieved as the Ni0/Ni2+ ratio reached about 1.57. This work not only provides an effective solution for the consumption of waste textiles, but also converts it into high value-added hydrogen-rich gas.

Advanced Copper Oxide Chemical and Green Synthesis: Characterization and Antibacterial Evaluation

Recent advancements in nanotechnology have improved the application of copper oxide (CuO) nanostructures, known for their diverse antibacterial, electrical, catalytic, optical, and pharmacological properties, which depend on nanoparticle morphology. This study investigated two synthesis methods for structured CuO: microwave-assisted hydrolysis and ultrasound using copper acetate and KOH, and an eco-friendly method involving cholesterol-free egg white albumin and Solanum lycopersicum extract. Characterization techniques, including XRD, FTIR, and SEM-EDS, were utilized to analyze the produced CuO. XRD confirmed high-purity monoclinic CuO structures in the sample obtained via the chemical method, while characteristic peaks of tenorite and dolerophanite were observed in the albumin-synthesized sample. ATR-FTIR analysis revealed O-H stretching bands around 3400 cm−1, indicating adsorbed H-OH or -OH and strong Cu-O bond peaks at 434 cm−1. The CuO synthesized via microwave and ultrasound methods displayed superior crystallinity compared to commercial CuO. SEM illustrated various morphologies, such as flakes, microspheres, and irregular polyhedra, influenced by the presence of proteins and organic acids. Antibacterial tests demonstrated the effective inhibition of Escherichia coli and Enterococcus faecalis, confirming the potential of CuO as a promising antibacterial agent. Overall, the findings highlight the effectiveness of green chemistry in developing crystalline CuO for various applications.

3D printed extended-release hydrochlorothiazide tablets.

In this study 3D printed tablets (printlets) with extended release of hydrochlorothiazide (HHT) as model active ingredient were designed and developed. Four formulations, F0.1SSE, F1SSE, F0.1DLP and F1DLP, have been manufactured and characterized, using non-typical semi-solid extrusion (SSE) with UV light solidification and digital light processing (DLP) techniques. Obtained rheological studies pointed out to F1SSE and F1DLP as more suitable for SSE and DLP printing, respectively. Photopolymerization process between photopolymer (PEGDA) and photoinitiator (DPPO; 0.1% and 1%) was investigated using FTIR, with PCA modeling utilized to analyze spectral variations over time and estimate crosslinking kinetics. SSE printlets averaged ∼6.5 mm in diameter, ∼3 mm in height and ∼110 mg in mass, while DLP printlets averaged ∼8.5 mm in diameter, ∼2.5 mm in height, with masses of ∼170 mg (F0.1DLP) and ∼220 mg (F1DLP). All four formulations complied to the requirements of European pharmacopeia for uniformity of dosage units of single dose preparations. In vitro release studies indicated extended-release profiles in both 0.1M Hydrochloric acid (HCl) and phosphate buffer pH 6.8 for SSE and DLP printlets. The release kinetics of HHT from the printlets were modeled to fit First order, Higuchi, Korsmeyer-Peppas and Hixson-Crowell equations and the most probable ones were determined based on the R2 values and Akaike information criterion. FTIR and Raman spectroscopic analyses of printlets confirmed the presence of characteristic peaks from both, HHT and excipients, as well as modifications in bonds due to the photopolymeric reaction.

CW laser beam-based reduction of graphene oxide films for gas sensing applications

In this study we present a room-temperature direct reduction of graphene oxide (GO) thin films using a laser. Our suggested method reduces solution-processed GO film onto substrate non-thermally using a continuous wave (CW) laser beam, using low laser power (15 mW), and low irradiation time (1 min.) compared with other laser reduction techniques. The characteristic broad peaks at 1360 and 1608 cm−1 corresponding to D and G bands of the reduced GO lattice, respectively, were observed in the Raman spectra of all samples, and their relative intensities were found to be influenced by the laser power and the exposure time. Besides being selective, fast, and non-contact operation without catalyst, this approach is cost-effective because of utilizing a CW laser beam instead of the expensive picosecond or femtosecond laser systems and using a low power laser source comparing with the methods published in the last two years. Then, we created a vertically aligned SiNWs gas sensor that was geared towards detecting ammonia (NH3) and carbon monoxide (CO) gas at mid-infrared (MIR) wavelengths. On Si wafers, SiNWs with a diameter of just 200 nm were developed. (MIR) gas sensing is particularly helpful and user-friendly since it detects gases immediately as they pass through the sensor’s active detecting region, preventing human contact with potentially dangerous chemicals.

Investigation of Dislocations Introduced in Si Wafer during Flash Lamp Annealing by Photoluminescence Spectroscopy

Dislocations are generated in Si wafers during flash lamp annealing for 20 ms. The samples have been etched to different depths and macro‐photoluminescence (PL) spectra have been recorded for different dislocation densities. A micro‐PL investigation is also carried out on a cross section of a sample. Four characteristic emission peaks are found, which are the well‐known D1, D2, D3, and D4 lines. The findings demonstrate a significant influence of the defect densities on the PL spectra of the D lines by using both the micro‐ and the macro‐PL setups, and show a correlation of the PL intensities with etch pit density measured against the depth of the wafer. Additionally, the D lines dependency on temperature is explored, offering insights into the underlying mechanisms. The D lines exhibit a pronounced temperature dependence, which can be attributed to various factors including phonon interactions and thermal expansion effects. The influence of nickel contamination is also examined.

Synthesis, photocatalytic activity for tetracycline degradation under visible light, and kinetic study of Ag/AgCl/ZIF-11 nanocomposite.

For the first time, Ag/AgCl/zeolitic imidazolate framework-11 nanocomposite (Ag/AgCl/ZIF-11) as photocatalyst was synthesized and investigated on tetracycline (TC) degradation under visible light. ZIF-11 (Z), Ag/AgCl (A), and four composites (AZ0.1Vis, AZ0.1UV24, AZ0.2UV12, AZ0.2UV24) were made and characterized by XRD, FTIR, Raman, BET, SEM, EDS, XPS, and DRS analysis. The characteristic peaks of ZIF-11 and Ag were observed at 4.3 and 38.2° in the XRD pattern of AZ0.2UV24, respectively. A good distribution of Ag/AgCl on the surface of ZIF-11 was observed by FESEM of AZ0.2UV24. The improvement of visible light absorption ability and reduced e-/h+ recombination of AZ0.2UV24 were confirmed by DRS and PL, respectively. The photocatalytic degradation of TC was described using the zero-order kinetic model with a degradation efficiency of 95.4%. The stability and reusability of AZ0.2UV24 were investigated during three consecutive cycles. Finally, the results of this study provide convincing evidence for using Ag/AgCl/ZIF-11 as highly efficient photocatalysts for removing TC from aqueous solutions.

Enhancing and modifying the optical, magnetic, and electrical features of PVA&PVP; composite filled with ZnFe2O4 nanoparticles for magneto-optical applications

Abstract This research employed a sol-gel method to synthesize zinc ferrite nanoparticles (ZnFe2O4 NPs). These nanoparticles were then dispersed within a blend of polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) (with a weight ratio of 50:50) to fabricate polymer nanocomposite samples (PNCSs) via a solution casting technique. The XRD patterns suggest significant structural alterations in the nanocomposite compared to the pure polymer blend, which is evident in changes in crystallinity and cluster size (D). At the same time, the atomic arrangement within the material remains unaffected (d spacing). The FTIR absorption spectra were analyzed to assess the miscibility of PVA and PVP, as well as their interactions with the ZnFe2O4 NPs. The presence of characteristic peaks for both polymers without significant shifting suggested good miscibility. The optical bandgap of the nanocomposite samples decreases from 4.79 to 3.16 eV, and the absorption edge gradually shifts toward longer wavelengths with the addition of ZnFe2O4 NPs. Thermal analysis using TGA was also conducted to investigate how the samples decompose with increasing temperature. Coats-Redfern and Broido models were also used to study the activation energy. The magnetic properties of the PVA/PVP-ZnFe₂O₄ nanocomposites were assessed using the VSM technique at room temperature, revealing ferromagnetic behavior with a significant increase in saturation magnetization (Ms), remanent magnetization (Mr), and loop area (La) as the ZnFe₂O₄ content increased. Across the frequency range of 0.1 Hz to 10 MHz, the PVA/PVP-ZnFe2O4 NP samples exhibited significantly improved electrical conductivity and dielectric properties. In addition, the dielectric properties and electric modulus of these PNCSs were studied, where the ZnFe2O4 NPs successfully improved the host matrix's capacity for storing energy. As a result, these interesting physicochemical characteristics show how well these PNCSs are suited for use in flexible-type micro- and optoelectronic methods, such as nanodielectric substrates, bandgap regulators, photosensors, and UV shielders.

Preparation and Evaluation of Carboxymethyl Cellulose from Recycling Paper Waste

In this study, the rapid production of carboxy methyl cellulose (CMC) from recycling waste paper with an average working hours including waste collection and product preparation up to 50 hours and An optimum temperature between 80-90 ° C using heater as an energy source. The obtained CMC was characterized via FTIR, XRD, techniques to ascertain its structure using two different technique heating with reflex. FTIR spectrum showed characteristic peaks of carboxy methyl cellulose groups and its salt at the wavenumbers of (C=O), (C-O), (C-O-C), and OH at different wavelength. Higher efficiency obtained from heating with reflex technique.

Morphological And Chemical Analysis of PAN/a-CNx Composites Membranes For CO₂ Separation

Thin polymeric membranes have attracted significant interest for CO₂ separation due to their high gas permeance and low cost. However, enhancing selectivity often requires an additional selective layer. This study investigates the role of amorphous carbon nitride (a-CNx) thin film deposited via radio-frequency plasma-enhanced chemical vapor deposition (RF-PECVD) as a selective layer on polyacrylonitrile (PAN) membrane fabricated through non-solvent induced phase separation (NIPS). Structural and chemical modifications of the membrane due to the introduction of a-CNx thin film were analyzed using Field Emission Scanning Electron Microscopy (FESEM), Brunauer-Emmett-Teller (BET) analysis, and Fourier-Transform Infrared Spectroscopy (FTIR). FESEM shows a textured surface on PAN/a-CNx membrane which confirmed the successful uniform deposition of the a-CNx thin film. BET revealed a slight reduction in BET surface area from 49.84 m²/g to 48.13 m²/g after deposition due to partial pore coverage by the a-CNx thin film. The Langmuir surface area increased from 89.94 m²/g to 97.08 m²/g, indicating the creation of more uniform adsorption sites. BJH analysis showed an increase in cumulative mesopore volume from 0.0994 cm³/g to 0.1073 cm³/g and a significant rise in mesopore width from 8.57 nm to 13.40 nm which implies the merging of smaller pores that led to increase mesoporosity. Both membranes exhibited Type IV isotherms with H3 hysteresis loops that represent characteristic of mesoporous materials, with the PAN/a-CNx membrane displaying a slightly wider hysteresis loop that indicates potential shifts toward slit-like pores. FTIR spectra confirmed the incorporation of a-CNx thin film into the PAN matrix, with characteristic peaks of N-H stretching, C=N stretching, and aromatic C-N stretching. The increase of nitrogen functionalities by the deposition of a-CNx thin film potentially increases CO₂ adsorption through acid-base interactions with nitrogen sites. These findings offer valuable insights for future research on high-performance gas separation membranes.

Casting Skin Dressing Containing Extractions of the Organic Part of Marine Sponges for Wound Healing.

Skin wounds are extremely frequent injuries related to many etiologies. They are a burden on healthcare systems worldwide. Skin dressings are the most popular therapy, and collagen is the most commonly used biomaterial, although new sources of collagen have been studied, especially spongin-like from marine sponges (SPG), as a promising source due to a similar composition to vertebrates and the ability to function as a cell-matrix adhesion framework. Despite evidence showing the positive effects of SPG for tissue healing, the effects of skin dressings manufactured are still limited. In this context, this study aimed at investigating the effects of collagen skin dressings in an experimental model of skin wounds in rats. For this purpose, SEM, FTIR, cell viability, morphological and morphometric aspects, collagen deposition, and immunostaining of TGF-β and FGF were evaluated. The results demonstrated micro- and macropores on the rough surface, peak characteristics of collagen, and no cytotoxicity for the skin dressing. Also, the control group (CG) after 5 and 10 days exhibited an intense inflammatory process and the presence of granulation tissue, while the treated group (TG) exhibited re-epithelialization after 10 days. The evaluation of granulation tissue and neoepithelial length had an intragroup statistical difference (p = 0.0216) and no intergroup difference. Birefringence demonstrated an organized mesh arranged in a network pattern, presenting type I and type III collagen fibers in all groups. Moreover, in the morphometric evaluation, there were no statistical differences in intergroups or time points for the different types of collagen evaluated. In conclusion, these findings may indicate that the dressing has not exacerbated the inflammatory process and may allow faster healing. However, further studies using a critical wound healing injury model should be used, associated with longer experimental periods of evaluation, to further investigate the effects of these promising therapeutic approaches throughout the skin repair process.

Synthesis of Gold Nanoparticles Using Cucurbitacin E-Glycoside and Methyl Gallate Isolated from Citrullus colocynthis L. Fruit and Evaluation of their Antibacterial and Antibiofilm Activities.

Metal nanoparticles have received much attention due to their unique physical dynamics, chemical reactivity, and promising biological applications. Green synthesis using natural compounds is an alternative to traditional chemical methods for the synthesis of nanoparticles. Herein, two secondary metabolites were isolated from different fractions of methanolic extract of Citrullus colocynthis (bitter apple) Schard. and identified as cucurbitacin Eglycoside (1) and methyl gallate (2). Both compounds were used in the green nanoformulation of gold nanoparticles. Mass spectrometry and NMR spectroscopy were used for structure elucidation of compound 1 and compound 2. UV-vis spectroscopy, FTIR, and AFM were performed to confirm the formation of AuNPs. The spectra of UV-Vis showed a characteristic peak at 519 nm and 548 nm for compounds 1 and 2, respectively. AuNPs ranged mostly between 1 and 50 nm measured using AFM. The FTIR analysis confirmed the presence of phytochemicals on the surface of AuNPs. The synthesized AuNPs showed good antibacterial activity against Escherichia coli, Bacillus subtilis, and Pseudomonas aeruginosa. The synthesized AuNPs demonstrated good antibiofilm activity against Streptococcus mutans. Thus, the green synthesized AuNPs can combat the pathogenicity of several human pathogens.

A Novel Label-Free Method for Efficient Detection of Bisphosphonate Drug Dissolution Rates Using Surface-Enhanced Raman Spectroscopy.

We developed a novel method utilizing surface-enhanced Raman spectroscopy (SERS) with calcium ion-modified silver nanoparticles as the enhancing substrate. This approach enables label-free detection of the dissolution rate of bisphosphonates. This technique is fast, sensitive, and highly reproducible, significantly advancing drug quality control. Experimental results demonstrated detection limits for etidronate, alendronate, and risedronate as low as 1 ng/mL. Notably, this method accurately identifies characteristic drug peaks without interference from excipients, allowing for precise quantitative detection. In summary, our SERS-based method offers a simple, efficient, and reliable approach for the qualitative and quantitative quality control of bisphosphonate drugs.

Stoichiometry effect on the structure, coordination and anticancer activity of gold(I/III) bisphosphine complexes.

Rationalizing the impact of oxidation states of Au-based complexes on function require synthetic strategies that allow for conserved molecular formula in Au(I) and their Au(III) counterparts. Oftentimes achieving Au(I) and Au(III) coordination complexes with the same ligand system is challenging due to the reactivity and stability of the starting Au(I) or Au(III) starting materials. Thus, attempts to study the impact of oxidation state on biological function has been elusive. We posit that Au complexes with the same ligand framework but different oxidation states will affect complex geometry and hence elicit differences in biological function or mechanism. In this work, we reacted 1,2-bis(diphenylphosphino)benzene with respective Au starting materials in different mole ratios to facilitate the synthesis of structurally distinct Au(I) or Au(III) complexes. Briefly, by reacting two stoichiometric equivalents of HAuCl4·3H2O or AuCl3(tht) with one equivalent of 1,2-bis(diphenylphosphino)benzene, we obtained dicationic bis-[1,2-bis-(diphenylphosphino)benzene]gold(III) chloride whereas an equimolar ratio of HAuCl4·3H2O and 1,2-bis(diphenylphosphino)benzene gave the monocationic bis-[1,2-bis-(diphenylphosphino)benzene]gold(I) complex in moderate yield. The complexes were characterized spectroscopically by HRMS, RP-HPLC-MS, NMR and the purity ascertained by elemental analysis. The 31P NMR showed characteristic singlet peak at ∼22 ppm for the Au(I) complexes and ∼57 ppm for the Au(III) complexes. The structure of the Au(III) complexes was further confirmed by X-ray crystallography as a 5-coordinate Au(III) complex. Although both Au(I) and Au(III) complexes showed promising anticancer activity in MDA-MB-231 (breast cancer) and BT-333 (glioblastoma) cancer cell lines and inhibited maximal mitochondria respiration in MDA-MB-231 cells, the Au(III) complexes further induce ROS accumulation and facilitate depolarization of the mitochondria membrane potential in MDA-MB-231 cells. Taken together, the synthetic approach provides a way to elucidate the effect of Au(I)/Au(III) oxidation states on structure, activity, and potential mechanism with respect to the same ligand.

Ultrafast Microwave-Synthesized 2D/1D MnO2/Carbon Nanotube Hybrid for Bilirubin Detection in Simulated Blood Serum.

Hybridization of carbon nanotubes (CNTs) and manganese dioxide (MnO2) integrates the biocompatibility and outstanding electrocatalytic activity of MnO2 with the exceptional conductivity of CNTs, thus providing a superior synergistic sensing platform for the detection of biomolecules. However, the existing methods for synthesizing MnO2/CNT hybrids are complex and inefficient, resulting in low yields and limited surface functionalities. Hence, in this study, we present a low-cost and ultrafast solid-phase synthesis of the MnO2/CNT hybrid using a facile microwave technique to detect a crucial biomolecule bilirubin. The successful synthesis of the MnO2/CNT hybrid is confirmed through characteristic Raman and X-ray diffraction peaks, while morphology is analyzed by imaging techniques such as FESEM and HRTEM. The MnO2/CNT/nickel foam (NF) sensor is thereafter used for the electrochemical detection of bilirubin. The sensor demonstrates a wide linear detection range from 10 nM to 1 mM, with a sensitivity of 6.87 mA nM-1 cm-2 toward bilirubin, as determined through the differential pulse voltammetry technique. The lower limit of detection is noted at 3.3 nM (=3.3 S/m). Furthermore, the as-fabricated sensor showcases high selectivity against the interfering species. Real-time analysis conducted in simulated blood serum using the standard addition method reveals an outstanding recovery percentage of approximately 98%. The conductive MnO2/CNT hybrid interacts robustly with bilirubin, aided by the porous NF substrate for stability, catalytic activity, and rapid electron transfer, enabling sensitive bilirubin detection. The work provides an ultrafast, low-cost, and high-yield solid-phase microwave synthesis of MnO2/CNT hybrid material and broadens its application in the detection of biological specimens for clinical diagnosis and biomedical research.

Tissue Sources Influence the Morphological and Morphometric Characteristics of Collagen Membranes for Guided Bone Regeneration.

(1) Background: Collagen, a natural polymer, is widely used in the fabrication of membranes for guided bone regeneration (GBR). These membranes are sourced from various tissues, such as skin, pericardium, peritoneum, and tendons, which exhibit differences in regenerative outcomes. Therefore, this study aimed to evaluate the morphological and chemical properties of porcine collagen membranes from five different tissue sources: skin, pericardium, dermis, tendons, and peritoneum. (2) Methods: The membrane structure was analyzed using energy-dispersive X-ray spectrometry (EDX), variable pressure scanning electron microscopy (VP-SEM), Fourier transform infrared spectroscopy (FTIR), and thermal stability via thermogravimetric analysis (TGA). The absorption capacity of the membranes for GBR was also assessed using an analytical digital balance. (3) Results: The membranes displayed distinct microstructural features. Skin- and tendon-derived membranes had rough surfaces with nanopores (1.44 ± 1.24 µm and 0.46 ± 0.1 µm, respectively), while pericardium- and dermis-derived membranes exhibited rough surfaces with macropores (78.90 ± 75.89 µm and 64.89 ± 13.15 µm, respectively). The peritoneum-derived membrane featured a rough surface of compact longitudinal fibers with irregular macropores (9.02 ± 3.70 µm). The thickness varied significantly among the membranes, showing differences in absorption capacity. The pericardium membrane exhibited the highest absorption, increasing by more than 10 times its initial mass. In contrast, the skin-derived membrane demonstrated the lowest absorption, increasing by less than 4 times its initial mass. Chemical analysis revealed that all membranes were primarily composed of carbon, nitrogen, and oxygen. Thermogravimetric and differential scanning calorimetry analyses showed no significant compositional differences among the membranes. FTIR spectra confirmed the presence of collagen, with characteristic peaks corresponding to Amide A, B, I, II, and III. (4) Conclusions: The tissue origin of collagen membranes significantly influences their morphological characteristics, which may, in turn, affect their osteogenic properties. These findings provide valuable insights into the selection of collagen membranes for GBR applications.

Exploring the physicochemical properties and antifungal activity of zinc oxide nanoparticles

ABSTRACT In this study, zinc oxide nanoparticles were synthesized using the chemical precipitation method with zinc acetate dihydrate and sodium hydroxide as precursors. UV-Vis spectroscopy confirmed the formation of ZnONPs, showing a characteristic absorption peak at around 360–370 nm, corresponding to a band gap energy of approximately 3.2 eV. XRD analysis indicated the crystalline nature of ZnONPs with a hexagonal wurtzite structure. FTIR and EDS analyses confirmed the presence of ZnONPs in the component. TEM revealed nearly spherical ZnONPs with average particle sizes of 26.1 nm for bare ZnONPs and 24.6 nm for PVP-capped ZnONPs. BET measurements showed a higher specific surface area for PVP-capped ZnONPs. The antifungal efficacy of ZnONPs was tested against Phytophthora capsici at concentrations ranging from 20 to 100 ppm. Results demonstrated significant inhibition of fungal growth, especially with PVP-capped ZnONPs, with complete inhibition at concentrations ≥60 ppm after 12 to 48 hours of incubation.

A Novel Multifunctional and Broadband Near‐Infrared Phosphor, Lu3MgGa3GeO12:Cr3+, Yb3+, Nd3+ Achieved through a Chemical Unit Substitution and Energy Transfer Strategy

AbstractCr3+‐doped near‐infrared (NIR) phosphors have attracted significant attention in recent years. Despite this, achieving high‐performance NIR phosphors with broadband emission and excellent thermal stability remains a considerable challenge. This study presents Lu3Ga5O12:Cr3+, which demonstrates a tunable emission peak ranging from 705 to 759 nm and an increased full‐width at half‐peak maximum (FWHM) from 46 to 139 nm by substituting the [Mg2+‐Ge4+] chemical unit for the [Ga3+‐Ga3+] unit. Additionally, in Lu3MgGa3GeO12:Cr3+, Yb3+, an energy transfer channel (Cr3+‐Yb3+) is constructed. Under blue light excitation, the characteristic emission peaks of Cr3+ (600–900 nm) and Yb3+ (900–1100 nm) are observed simultaneously. However, the emission band between 850 and 900 nm is relatively weak, resulting in a discontinuous emission spectrum. To address this, Lu3MgGa3GeO12:Cr3+, Yb3+, Nd3+ phosphors are proposed, which exhibit a continuous broadband NIR emission with a FWHM of 253 nm and internal quantum efficiency of 47.3%. The luminescence intensity retains 81% of its room temperature value even at 423 K. Combining this new phosphor with a blue LED chip results in a portable NIR light source with potential applications in non‐destructive detection, information encryption, bio‐imaging, and NIR remote control. This work offers a novel perspective for developing high‐performance NIR phosphors.

Quality Assessment of Gegen Zhitong Mixture Based on Chemical Fingerprints Combined with Quantitative Analysis of Multi‐Components with a Single‐Marker

ABSTRACTTraditional Chinese medicine (TCM) formulas were one of the most important treasures in TCMs. Gegen Zhitong mixture (GGZTM) was a Chinese medicine preparation (CMP) developed by Wuhan No.1 Hospital according to a TCM formula. The comprehensive quality assessment of CMPs is necessary to ensure their safe and effective use for medical purposes. However, the existing quality evaluation of GGZTM was limited to the content determination of a single marker compound, making it difficult to fully monitor its overall quality. Therefore, an approach that profiled a comprehensive chemical description of GGZTM based on high‐performance liquid chromatography was developed for the first time, and the characteristic common peaks of GGZTM were identified in the present study. Secondly, a quantitative analysis of multi‐components with a single‐marker (QASM) was developed, which could be employed to simultaneously determine the content of three components in GGZTM. Finally, the laboratory prepared a self‐made GGZTM according to the prescription composition and systematically compared it with the GGZTM through similarity analysis and hierarchical cluster analysis based on chemical fingerprints and the content of intrinsic marker components. In conclusion, the developed method is accurate and stable and can be applied to quality control in the production process of GGZTM.

Biodegradable trays made from Poraqueiba serícea Tulasne seed starch and Zea Mays cob flour

The environmental impact of polystyrene and other petrochemical packaging has increased interest in researching biodegradable materials as alternatives. The main objective of this research was to develop biodegradable trays from five formulations of Poraqueiba sericea Tulasne (known as umari) seed starch and corn cob meal. The trays were produced using the thermoforming process applying temperatures of 135°C and 145°C for each side of the tray for a time of 6.5 min. Physical analysis of the trays showed that the increase in the percentage of corn cob flour caused changes in color (L*: 68.69 - 64.94), thickness (2.20 - 3.17 mm), density (0.251 - 0.414 g/cm3), moisture (3.85 - 5.68%), water absorption (21.86 - 39.05%), volatile solids (95.33 - 98.31%). Regarding mechanical properties, it was also evidenced the increase in hardness (67.70 - 90.97 N), fracturability (1.43 and 3.19 mm), tension (2.84 to 3.43 MPa) and elongation (1.54 to 2.04%). The formulation of 87.5% umari seed starch and 12.5% tusa flour presented more favorable physical and mechanical properties. Further analysis of this formulation was performed by Fourier transform infrared spectroscopy (FTIR), which identified bands characteristic of starch (1055 and 1027 cm-1); X-ray diffraction (XRD), which revealed characteristic peaks (2θ = 16.83° and 2θ = 22.69°) associated with cellulose crystallinity in the biodegradable tray; and scanning electron microscopy (SEM), which revealed cellulosic voids with irregular distribution due to the addition of fibers. Future research should examine the potential applications of these biodegradable trays for the packaging of raw materials in the food industry.