Isolation, identification, and molecular characterization of probiotic bacteria from locally selected Ethiopian free range chickens gastrointestinal tract

The poultry industry is facing continuous challenges with regard to increased feed costs and loss due to infectious disease. To overcome this challenge, several antibiotics have been used along with chicken feeds to promote growth. Nevertheless, the use of antibiotics as growth promoter has been banned in many countries, due to the concerns associated with potential risks of emerging and horizontal transfer of multidrug resistant genes to bacteria in animal tissues. The objective of this study was to identify and characterize potential probiotic bacteria strains from the gastrointestinal tract of free-range locally selected chickens. The bacterial isolates were screened, purified and characterized based on morphological, biochemical and molecular characteristics from 12 well-adopted free-range healthy young chickens. Low pH and bile salt tolerance, antagonistic activity, antibiotic activity, hemolysis activity, adhesion to the chicken intestine and carbohydrate fermentation tests was conducted to identify potential probiotic bacteria. Twelve bacterial isolates were screened based on their ability for their tolerance to low pH and bile salt. The isolates were identified by using 16S rRNA gene partial sequencing method. All screened isolates showed great survival percentage at low pH, that is (89.2 ± 0.75 to 97.1 ± 0.64) survived at 3 h and (83.6 ± 0.75 to 95.2 ± 0.63) at 6 h challenge at pH2. Isolate GCM112 was the least tolerant strain in 6.0% salt concentration at 12 and 24 h exposure time (82.1 ± 1.28 and 79.9 ± 1.96%) respectively. The result revealed no strain tests in this study exhibited α- and β-hemolytic activity when cultured in sheep blood agar. Most isolated strains showed best growth at 37°C temperature and up to 4% NaCl concentration. Based on the reported result from in vitro data, GCH212 and GCM412 isolates were recognized as best potential probiotic bacteria for chicken against pathogens but further studies are needed on in vivo assessment on the health benefits in the real life situation.

A Review of Solid-State Proton-Polymer Batteries: Materials and Characterizations

The ever-increasing global population necessitates a secure and ample energy supply, the majority of which is derived from fossil fuels. However, due to the immense energy demand, the exponential depletion of these non-renewable energy sources is both unavoidable and inevitable in the approaching century. Therefore, exploring the use of polymer electrolytes as alternatives in proton-conducting batteries opens an intriguing research field, as demonstrated by the growing number of publications on the subject. Significant progress has been made in the production of new and more complex polymer-electrolyte materials. Specific characterizations are necessary to optimize these novel materials. This paper provides a detailed overview of these characterizations, as well as recent advancements in characterization methods for proton-conducting polymer electrolytes in solid-state batteries. Each characterization is evaluated based on its objectives, experimental design, a summary of significant results, and a few noteworthy case studies. Finally, we discuss future characterizations and advances.

The Antibacterial Activities and Characterizations of Biosynthesized Zinc Oxide Nanoparticles, and Their Coated with Alginate Derived from Fucus vesiculosus

Zinc oxide nanoparticles have many advantages for nano-biotechnologists due to their intense biomedical applications. ZnO-NPs are used as antibacterial agents, which influence bacterial cells through the rupture of the cell membrane and the generation of reactive free radicals. Alginate is a polysaccharide of natural origin due to its excellent properties that are used in various biomedical applications. Brown algae are good sources of alginate and are used as a reducing agent in the synthesis of nanoparticles. This study aims to synthesize ZnO-NPs by using brown alga Fucus vesiculosus (Fu/ZnO-NPs) and also to extract alginate from the same alga, which is used in coating the ZnO-NPs (Fu/ZnO-Alg-NCMs). The characterizations of Fu/ZnO-NPs and Fu/ZnO-Alg-NCMs were determined by FTIR, TEM, XRD, and zeta potential. The antibacterial activities were applied against multidrug resistance bacteria of both gram-positive and negative. The results obtained in FT-TR showed there are some shifts in the peak positions of Fu/ZnO-NPs and Fu/ZnO-Alg-NCMs. The peak at 1655 cm^-1, which assigned amide I-III, is present in both Fu/ZnO-NPs and Fu-Alg-ZnO-NCMs; this band is responsible for bio-reductions and stabilization of both nanoparticles. The TEM images proved the Fu/ZnO-NPs have rod shapes with sizes ranging from 12.68 to 17.66 and are aggregated, but Fu/ZnO/Alg-NCMs are spherical in shape with sizes ranging from 12.13 to 19.77. XRD-cleared Fu/ZnO-NPs have nine sharp peaks that are considered good crystalline, but Fu/ZnO-Alg-NCMs have four broad and sharp peaks that are considered semi-crystalline. Both Fu/ZnO-NPs and Fu/ZnO-Alg-NCMs have negative charges (-1.74 and -3.56, respectively). Fu/ZnO-NPs have more antibacterial activities than Fu/ZnO/Alg-NCMs in all tested multidrug-resistant bacterial strains. Fu/ZnO/Alg-NCMs had no effect on Acinetobacter KY856930, Staphylococcus epidermidis, and Enterobacter aerogenes, whereas there was an apparent effect of ZnO-NPs against the same strains.

Correlating Solid Electrolyte Interphase Composition with Dendrite-Free and Long Life-Span Lithium Metal Batteries via Advanced Characterizations and Simulations

Lithium metal anode attracts great attention because of its high specific capacity and low redox potential. However, the uncontrolled dendrite growth and its infinite volume expansion during cycling are extremely detrimental to the practical application. The formation of a solid electrolyte interphase (SEI) plays a decisive role in the behavior of lithium deposition/dissolution during electrochemical processing. Clarifying the essential relationship between SEI and battery performance is a priority. Research in SEI is accelerated in recent years by the use of advanced simulation tools and characterization techniques. The chemical composition and micromorphology of SEIs with various electrolytes are analyzed to clarify the effects of SEI on the Coulombic efficiency and cycle life. In this review, the recent research progress focused on the composition and structure of SEI is summarized, and various advanced characterization techniques applied to the investigation of SEI are discussed. The comparisons of the representative experimental results and theoretical models of SEI in lithium metal batteries (LMBs) are exhibited, and the underneath mechanisms of interaction between SEI and the electrochemical properties of the cell are highlighted. This work offers new insights into the development of safe LMBs with higher energy density.

Metal Oxide-Supported Metal Catalysts for Electrocatalytic Oxygen Reduction Reaction: Characterization Methods, Modulation Strategies, and Recent Progress

The sluggish kinetics of the oxygen reduction reaction (ORR) with complex multielectron transfer steps significantly limits the large-scale application of electrochemical energy devices, including metal-air batteries and fuel cells. Recent years witnessed the development of metal oxide-supported metal catalysts (MOSMCs), covering single atoms, clusters, and nanoparticles. As alternatives to conventional carbon-dispersed metal catalysts, MOSMCs are gaining increasing interest due to their unique electronic configuration and potentially high corrosion resistance. By engineering the metal oxide substrate, supported metal, and their interactions, MOSMCs can be facilely modulated. Significant progress has been made in advancing MOSMCs for ORR, and their further development warrants advanced characterization methods to better understand MOSMCs and precise modulation strategies to boost their functionalities. In this regard, a comprehensive review of MOSMCs for ORR is still lacking despite this fast-developing field. To eliminate this gap, advanced characterization methods are introduced for clarifying MOSMCs experimentally and theoretically, discuss critical methods of boosting their intrinsic activities and number of active sites, and systematically overview the status of MOSMCs based on different metal oxide substrates for ORR. By conveying methods, research status, critical challenges, and perspectives, this review will rationally promote the design of MOSMCs for electrochemical energy devices.

Characterization of various tandem solar cells: Protocols, issues, and precautions

In the search for a more efficient solar cell, various types of tandem solar cells (TSCs) have been actively developed worldwide as the performances of the single junction solar cells approach their theoretical limits. Meanwhile, various materials and structures are adopted in TSCs, which makes their characterizations and comparison difficult. Along with the classical monolithic TSC, which exhibits two electrical contacts, devices with three or four electrical contacts have been widely studied as a more performing alternative of commercialized solar cells. For a fair and accurate evaluation of the device performance of TSCs, understanding the effectiveness and limitations of the characterization of the different types of TSCs is crucial. In this paper, we summarize various types of TSCs and discuss their characterization methods.

Highly effective Fe-doped TiO2nanoparticles for removal of toxic organic dyes under visible light illumination

This article addresses the synthesis of Fe³⁺doped TiO₂nanoparticles with variations of molar concentrations of Fe³⁺and their adequate use as potential photocatalysts for Photocatalysis applications. Synthesized photocatalysts were characterized thoroughly by different analytical techniques in terms of morphological, chemical, structural, crystalline, optical, electronic structure, surface area etc properties. The occurrence of red shift phenomenon of the energy band gap attributes to the transfer of charges and transition between the d electrons of dopant and conduction band (CB) or valence band (VB) of TiO₂. The doping of Fe³⁺ions generates more trap sites for charge carriers with the surface trap sites. Thorough experimental conclusions revealed that the Fe³⁺ions necessarily regulate the catalytic property of TiO₂nanomaterial. The obtained total degradation efficiency rate of Methylene Blue (MB) was 93.3% in the presence of 0.1 M Fe³⁺in the host material and for Malachite Green Oxalate the efficiency was 100% in the presence of 0.05 M and 0.1 M Fe³⁺in the host material. In both the cases the total visible light irradiation time was 90 min. The adsorption properties of the photocatalysts have been also performed in a dark for 90 min in the presence of MB dye. However, till now there are hardly reported photocatalysts which shows complete degradation of these toxic organic dyes by visible light driven photocatalysis. of potential values of valence and conduction band shows the production of active oxidizing species for hydrogen yield and the possible mechanism of the Schottky barrier has been proposed. A schematic diagram of visible light driven Photocatalysis has been pictured showing degradation activity of Fe³⁺-TiO₂catalysts sample.

From Conventional to Microfluidic: Progress in Extracellular Vesicle Separation and Individual Characterization

Extracellular vesicles (EVs) are nanoscale membrane vesicles, which contain a wide variety of cargo such as proteins, miRNAs, and lipids. A growing body of evidence suggests that EVs are promising biomarkers for disease diagnosis and therapeutic strategies. Although the excellent clinical value, their use in personalized healthcare practice is not yet feasible due to their highly heterogeneous nature. Taking the difficulty of isolation and the small size of EVs into account, the characterization of EVs at a single-particle level is both imperative and challenging. In a bid to address this critical point, more research has been directed into a microfluidic platform because of its inherent advantages in sensitivity, specificity, and throughput. This review discusses the biogenesis and heterogeneity of EVs and takes a broad view of state-of-the-art advances in microfluidics-based EV research, including not only EV separation, but also the single EV characterization of biophysical detection and biochemical analysis. To highlight the advantages of microfluidic techniques, conventional technologies are included for comparison. The current status of artificial intelligence (AI) for single EV characterization is then presented. Furthermore, the challenges and prospects of microfluidics and its combination with AI applications in single EV characterization are also discussed. In the foreseeable future, recent breakthroughs in microfluidic platforms are expected to pave the way for single EV analysis and improve applications for precision medicine.

Oscillatoria limnetica Mediated Green Synthesis of Iron Oxide (Fe(2)O(3)) Nanoparticles and Their Diverse In Vitro Bioactivities

Iron oxide nanoparticles (Fe₂O₃-NPs) were synthesized using Oscillatoria limnetica extract as strong reducing and capping agents. The synthesized iron oxide nanoparticles IONPs were characterized by UV-visible spectroscopy, Fourier transform infrared (FTIR), X-ray diffractive analysis (XRD), scanning electron microscope (SEM), and Energy dispersive X-ray spectroscopy (EDX). IONPs synthesis was confirmed by UV-visible spectroscopy by observing the peak at 471 nm. Furthermore, different in vitro biological assays, which showed important therapeutic potentials, were performed. Antimicrobial assay of biosynthesized IONPs was performed against four different Gram-positive and Gram-negative bacterial strains. E. coli was found to be the least suspected strain (MIC: 35 µg/mL), and B. subtilis was found to be the most suspected strain (MIC: 14 µg/mL). The maximum antifungal assay was observed for Aspergillus versicolor (MIC: 27 µg mL). The cytotoxic assay of IONPs was also studied using a brine shrimp cytotoxicity assay, and LD₅₀ value was reported as 47 µg/mL. In toxicological evaluation, IONPs was found to be biologically compatible to human RBCs (IC₅₀: >200 µg/mL). The antioxidant assay, DPPH 2,2-diphenyl-1-picrylhydrazyly was recorded at 73% for IONPs. In conclusion, IONPs revealed great biological potential and can be further recommended for in vitro and in vivo therapeutic purposes.

Recent Patents of Pharmaceutical Co-Crystals: Product Development on Anti-Cancer Drugs and Beyond

BACKGROUND

Scientists, academicians, and researchers from academics and the pharmaceutical industries have all expressed interest in the design and production of pharmaceutical cocrystals in recent years. The development of novel drug products with enhanced physicochemical and pharmacological characteristics is aided by the cocrystallization of drug substances.

OBJECTIVE

The major problem with drug candidates is their solubility and bioavailability, which may be solved with the appropriate molecular modifications. The failure of most drug candidates in earlier clinical trials is also reawakening interest. In that connection, pharmaceutical cocrystals are vital in the development of dosage forms in the field of pharmaceutical technology. The goal of this manuscript is to provide a comprehensive overview of cocrystal synthesis methods and characterization techniques.

CONCLUSION

In this review, it is evident that the solvent-free technique has several benefits over solvent-based approaches in the design and production of pharmaceutical cocrystals, and that these methodologies can also open opportunities for further advancement in the field of cocrystal synthesis. This manuscript provides a brief overview of each technique for manufacturing pharmaceutical cocrystals and an analysis of cocrystals. This manuscript has highlighted points on whether cocrystals comply with the requirements for intellectual property rights and how they will impact the current pharmaceutical industry. The impact of recent patents on pharmaceutical cocrystals is examined in depth with relevant examples.

Preparation of Cellulose Nanocrystals from Jujube Cores by Fractional Purification

Jujube cores are fiber-rich industrial waste. Dewaxing, alkali treatment, bleaching, and sulfuric acid hydrolysis were used to generate cellulose nanocrystals (CNCs) from the jujube cores in this study. The morphological, structural, crystallinity, and thermal properties of the fibers were investigated using FE-SEM, TEM, AFM, FT-IR, XRD, and TGA under various processes. CNCs’ zeta (ζ) potential and water contact angle (WAC) were also investigated. The findings demonstrate that non-fibrous components were effectively removed, and the fiber particles shrunk over time because of many activities. CNCs had a rod-like shape, with a length of 205.7 ± 52.4 nm and a 20.5 aspect ratio. The crystal structure of cellulose Iβ was preserved by the CNCs, and the crystallinity was 72.36%. The temperature of the fibers’ thermal degradation lowered during the operations, although CNCs still had outstanding thermal stability (>200 °C). Aside from the CNCs, the aqueous suspension of CNCs was slightly agglomerated; thus, the zeta (ζ) potential of the CNCs’ suspension was −23.72 ± 1.7 mV, and the powder had high hydrophilicity. This research will be valuable to individuals who want to explore the possibility for CNCs made of jujube cores.

Thermoplastic starch nanocomposites: sources, production and applications - a review

The development of materials based on thermoplastic starch (TPS) is an excellent alternative to replace or reduce the use of petroleum-derived polymers. The abundance, renewable origin, biodegradability, biocompatibility, and low cost of starch are among the advantages related to the application of TPS compared to other thermoplastic biopolymers. However, through the literature review, it was possible to observe the need to improve some properties, to allow TPS to replace commonly used polyolefins. The studies reviewed achieved these modifications were achieved by using plasticizers, adjusting processing conditions, and incorporating fillers. In this sense, the addition of nanofillers proved to be the main modification strategy due to the large number of available nanofillers and the low charge concentration required for such improvement. The improvement can be seen in thermal, mechanical, electrical, optical, magnetic, antimicrobial, barrier, biocompatibility, cytotoxicity, solubility, and swelling properties. These modification strategies, the reviewed studies described the development of a wide range of materials. These are products with great potential for targeting different applications. Thus, this review addresses a wide range of essential aspects in developing of this type of nanocomposite. Covering from starch sources, processing routes, characterization methods, the properties of the obtained nanocomposites, to the various applications. Therefore, this review will provide an overview for everyone interested in working with TPS nanocomposites. Through a comprehensive review of the subject, which in most studies is done in a way directed to a specific area of study.

Implication and evaluations of indoor soot particles from domestic fuel energy sources using characterization techniques in northern Pakistan

Soot particles emitted from the burning of solid fuel sources in the households carry important environmental and public health implications. In this study, the indoor soot particles released from firewood, cow dung, and bagasse burning at households of selected rural areas of Khyber Pakhtunkhwa province of Pakistan were investigated by characterization analyses to study its morphological and elemental compositions. Results demonstrated diverse compositions of soot particles from each fuel source. The surface areas of soot particles emitted by the firewood, cow dung, and bagasse were about 0.3, 0.4, and 8.64 m²  g^-1 , respectively. For the soot particles emitted by the firewood burning, the major functional groups for aromatic compounds were C═C at the 1,431-1,599 at 1,000-2,000 cm^-1 . The absorbance rate of alkanes was about 1,599-1,431 at 1,000-2,000 cm^-1 . However, silicon band vibration was more prominent in bagasse soot particles as compared to other samples. The emission of soot particles with high surface area in the atmosphere could provide an elevated adsorption sites for atmospheric pollution and trap more energy resulting in increased atmospheric temperature. Findings from the present study suggest that current households' fuel combustion practices significantly contribute to increase the particulate matter in the atmosphere and possible enhance climate change phenomenon and related disasters in northern Pakistan.

Inhibition of microbial growth by silver nanoparticles synthesized from Fraxinus xanthoxyloides leaf extract

AIMS

Conventional antibiotics have been failed to treat infectious diseases due to emergence of multidrug resistance (MDR) in some common pathogens. The current study aimed to formulate new antimicrobials from greener sources. In the midst of these efforts, nanotechnology is a newly emerged field, in which the synthesis of new nanoparticles through novel and efficient means is on the rise.

METHODS AND RESULTS

The current work has been carried out to assess the potential of Fraxinus xanthoxyloides (FX) leaf extract in biosynthesis of silver nanoparticles (FX-AgNPs). This method is economical and simple one-step approach to synthesize AgNPs. Characterization of FX-AgNPs has been done by UV-Visible spectroscopy, scanning electron microscope (SEM), X-ray diffraction (XRD), transmission electronic microscope (TEM) and Fourier transforms infrared spectroscopy (FT-IR). The formation of FX-AgNPs has confirmed through UV-Visible spectroscopy (at 430 nm) by change of colour owing to surface Plasmon resonance. Based on the XRD pattern, the crystalline property of FX-AgNPs has established. Functional groups existing in F. xanthoxyloides leaf extract are confirmed by FT-IR spectrum. SEM and TEM authenticated morphology of the AgNPs. The newly synthesized nanoparticles were evaluated for their antimicrobial potential. Minimum inhibitory concentration was determined against Escherichia coli, methicillin-resistant Staphylococcus aureus (MRSA) strains, Pseudomonas aeruginosa and Candida albicans by microtiter plate assay. The lowest inhibition (69%) observed against MRSA was at a concentration of 50 ppm FX-AgNPs and maximum inhibition (81%) observed was against P. aeruginosa. The biosynthesized AgNPs triggered up to 68·6% reduction of the P. aeruginosa biofilm when compared to the control.

CONCLUSION

It can be concluded that nanoparticles could be a better alternative of antibiotics with greater efficacies and represent a valuable milestone to fight against infections caused by MDR pathogens.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study imparts a useful insight into the development of a new antimicrobial agent from a novel source.

Investigation of the Interaction between N-Acetyl-l-Cysteine and Ovalbumin by Spectroscopic Studies, Molecular Docking Simulation, and Real-Time Quartz Crystal Microbalance with Dissipation

This study investigated the interaction between N-acetyl-l-cysteine (NAC) and ovalbumin (OVA) using multispectroscopic technology, molecular docking, and quartz crystal microbalance with dissipation (QCM-D). Fluorescence intensity and UV absorption of OVA were decreased substantially upon the addition of NAC. The calculated K_q values were obtained at 298, 304, and 310 K for 13.48, 15.59, and 17.50 (× 10¹² L mol^-1), respectively, suggesting that the static quenching was dominated. Thermodynamic parameters such as ΔH (-150.58 kJ mol^-1), ΔS (-433.51 J mol^-1 K^-1), and ΔG values (-21.39 kJ mol^-1), combined with molecular docking and QCM-D data, showed that the interaction was spontaneous and van der Waals and hydrogen bonding were identified as the main driving forces. FTIR and CD results showed that the α-helix content of OVA increased from 2.8 to 22.9%, and the β-sheet decreased from 0.2 to 21.9% in the presence of 5 and 10 μM NAC, respectively, compared to the pure OVA, respectively.

Characterization Study of Empty Fruit Bunch (EFB) Fibers Reinforcement in Poly(Butylene) Succinate (PBS)/Starch/Glycerol Composite Sheet

In this study, a mixture of thermoplastic polybutylene succinate (PBS), tapioca starch, glycerol and empty fruit bunch fiber was prepared by a melt compounding method using an industrial extruder. Generally, insertion of starch/glycerol has provided better strength performance, but worse thermal and water uptake to all specimens. The effect of fiber loading on mechanical, morphological, thermal and physical properties was studied in focus. Low interfacial bonding between fiber and matrix revealed a poor mechanical performance. However, higher fiber loadings have improved the strength values. This is because fibers regulate good load transfer mechanisms, as confirmed from SEM micrographs. Tensile and flexural strengths have increased 6.0% and 12.2%, respectively, for 20 wt% empty fruit bunch (EFB) fiber reinforcements. There was a slightly higher mass loss for early stage thermal decomposition, whereas regardless of EFB contents, insignificant changes on decomposition temperature were recorded. A higher lignin constituent in the composite (for high natural fiber volume) resulted in a higher mass residue, which would turn into char at high temperature. This observation indirectly proves the dimensional integrity of the composite. However, as expected, with higher EFB fiber contents in the composite, higher values in both the moisture uptake and moisture loss analyses were found. The hydroxyl groups in the EFB absorbed water moisture through formation of hydrogen bonding.

Polystyrene Magnetic Nanocomposites as Antibiotic Adsorbents

There are different ways for antibiotics to enter the aquatic environment, with wastewater treatment plants (WWTP) considered to be one of the main points of entrance. Even treated wastewater effluent can contain antibiotics, since WWTP cannot eliminate the presence of antibiotics. Therefore, adsorption can be a sustainable option, compared to other tertiary treatments. In this direction, a versatile synthesis of poly(styrene-block-acrylic acid) diblock copolymer/Fe3O4 magnetic nanocomposite (abbreviated as P(St-b-AAc)/Fe3O4)) was achieved for environmental applications, and particularly for the removal of antibiotic compounds. For this reason, the synthesis of the P(St-b-AAc) diblock copolymer was conducted with a reversible addition fragmentation transfer (RAFT) method. Monodisperse superparamagnetic nanocomposite with carboxylic acid groups of acrylic acid was adsorbed on the surface of Fe3O4 nanoparticles. The nanocomposites were characterized with scanning electron microscopy (SEM), X-ray diffraction (XRD) and vibrating sample magnetometer (VSM) analysis. Then, the nanoparticles were applied to remove ciprofloxacin (antibiotic drug compound) from aqueous solutions. The effects of various parameters, such as initial drug concentration, solution pH, adsorbent dosage, and contact time on the process were extensively studied. Operational parameters and their efficacy in the removal of Ciprofloxacin were studied. Kinetic and adsorption isothermal studies were also carried out. The maximum removal efficiency of ciprofloxacin (97.5%) was found at an initial concentration of 5 mg/L, pH 7, adsorbent's dosage 2 mg/L, contact time equal to 37.5 min. The initial concentration of antibiotic and the dose of the adsorbent presented the highest impact on efficiency. The adsorption of ciprofloxacin was better fitted to Langmuir isotherm (R2 = 0.9995), while the kinetics were better fitted to second-order kinetic equation (R2 = 0.9973).

Barrier Properties and Characterizations of Poly(lactic Acid)/ZnO Nanocomposites

This study aimed to reinforce the barrier performance (i.e., oxygen-gas and water-vapor permeability) of poly(lactic acid) (PLA)-based films. Acetyltributylcitrate and zinc oxide nanoparticle (nano-ZnO), serving as plasticizer and nanofiller, respectively, were blended into a PLA matrix through a solvent-volatilizing method. The structural, morphological, thermal, and mechanical performances were then studied. Scanning electron microscopic images showed a significant dispersion of nano-ZnO in PLA ternary systems with low nano-ZnO content. The interaction between PLA matrix and ZnO nanoparticles was further analyzed by Fourier-transform infrared spectroscopy. Wide-angle X-ray scattering spectroscopy demonstrated high compatibility between PLA matrix and ZnO nanoparticles. Mechanical property studies revealed good tensile strength and low flexibility. Differential scanning calorimetry curves proved that an amorphous structure mostly existed in PLA ternary systems. The improvements in barrier property and tensile strength indicated that the PLA/nano-ZnO composite films could be used for food packaging application.

Encapsulation of gemcitabine in RGD-modified nanoliposomes improves breast cancer inhibitory activity

In this study, RGD coated GEM liposomes were prepared by the emulsification-solvent evaporation method. The in vitro and in vivo characterizations were done to evaluate the feasibility of application. The mean particle size of the prepared liposomes was found to be 165.6 ± 15.7 nm. The entrapment efficiency and drug loading of the formulation were 82.4% ± 7.2% and 10.1% ± 1.4%, respectively. The liposomes were negatively charged with a zeta potential of -25.8 mV. The surface morphology of RGD-GEM liposomes was spherical and smooth. After three months of storage at different conditions, lyophilized liposomes appeared to be stable since they showed no collapse or contraction. The Weibull model was the most appropriate kinetic model for RGD-GEM liposomes, showing that the release of GEM from the liposomes was in the manners of both dissolution and diffusion. In vivo, the additive cytotoxicity of RGD-GEM-LPs in our study was caused by the presence of RGD which is more effective in the treatment of breast cancer devoid of toxicity to normal cells. Liposomes could also significantly extend the role of GEM in vivo and showed higher bioavailability than solution.

Synthesis, Principles, and Properties of Magnetite Nanoparticles for In Vivo Imaging Applications-A Review

The current nanotechnology era is marked by the emergence of various magnetic inorganic nanometer-sized colloidal particles. These have been extensively applied and hold an immense potential in biomedical applications including, for example, cancer therapy, drug nanocarriers (NCs), or in targeted delivery systems and diagnosis involving two guided-nanoparticles (NPs) as nanoprobes and contrast agents. Considerable efforts have been devoted to designing iron oxide NPs (IONPs) due to their superparamagnetic (SPM) behavior (SPM IONPs or SPIONs) and their large surface-to-volume area allowing more biocompatibility, stealth, and easy bonding to natural biomolecules thanks to grafted ligands, selective-site moieties, and/or organic and inorganic corona shells. Such nanomagnets with adjustable architecture have been the topic of significant progresses since modular designs enable SPIONs to carry out several functions simultaneously such as local drug delivery with real-time monitoring and imaging of the targeted area. Syntheses of SPIONs and adjustments of their physical and chemical properties have been achieved and paved novel routes for a safe use of those tailored magnetic ferrous nanomaterials. Herein we will emphasis a basic notion about NPs magnetism in order to have a better understanding of SPION assets for biomedical applications, then we mainly focus on magnetite iron oxide owing to its outstanding magnetic properties. The general methods of preparation and typical characteristics of magnetite are reviewed, as well as the major biomedical applications of magnetite.

Nanostructured ZnO in a Metglas/ZnO/Hemoglobin Modified Electrode to Detect the Oxidation of the Hemoglobin Simultaneously by Cyclic Voltammetry and Magnetoelastic Resonance

In the present work, a nanostructured ZnO layer was synthesized onto a Metglas magnetoelastic ribbon to immobilize hemoglobin (Hb) on it and study the Hb’s electrochemical behavior towards hydrogen peroxide. Hb oxidation by H₂O₂ was monitored simultaneously by two different techniques: Cyclic Voltammetry (CV) and Magnetoelastic Resonance (MR). The Metglas/ZnO/Hb system was simultaneously used as a working electrode for the CV scans and as a magnetoelastic sensor excited by external coils, which drive it to resonance and interrogate it. The ZnO nanoparticles for the ZnO layer were grown hydrothermally and fully characterized by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and photoluminescence (PL). Additionally, the ZnO layer’s elastic modulus was measured using a new method, which makes use of the Metglas substrate. For the detection experiments, the electrochemical cell was performed with a glass vial, where the three electrodes (working, counter and reference) were immersed into PBS (Phosphate Buffer Solution) solution and small H₂O₂ drops were added, one at a time. CV scans were taken every 30 s and 5 min after the addition of each drop and meanwhile a magnetoelastic measurement was taken by the external coils. The CV plots reveal direct electrochemical behavior of Hb and display good electrocatalytic response to the reduction of H₂O₂. The measured catalysis currents increase linearly with the H₂O₂ concentration in a wide range of 25–350 μM with a correlation coefficient 0.99. The detection limit is 25–50 μM. Moreover, the Metglas/ZnO/Hb electrode displays rapid response (30 s) to H₂O₂, and exhibits good stability and reproducibility of the measurements. On the other hand, the magnetoelastic measurements show a small linear mass increase versus the H₂O₂ concentration with a slope of 152 ng/μM, which is probably due to H₂O₂ adsorption in ZnO during the electrochemical reaction. No such effects were detected during the control experiment when only PBS solution was present for a long time.

Seed-Assisted Growth of Single-Crystalline Patterned Graphene Domains on Hexagonal Boron Nitride by Chemical Vapor Deposition

Vertical heterostructures based on two-dimensional layered materials, such as stacked graphene and hexagonal boron nitride (G/h-BN), have stimulated wide interest in fundamental physics, material sciences and nanoelectronics. To date, it still remains challenging to obtain high quality G/h-BN heterostructures concurrently with controlled nucleation density and thickness uniformity. In this work, with the aid of the well-defined poly(methyl methacrylate) seeds, effective control over the nucleation densities and locations of graphene domains on the predeposited h-BN monolayers was realized, leading to the formation of patterned G/h-BN arrays or continuous films. Detailed spectroscopic and morphological characterizations further confirmed that ∼85.7% of such monolayer graphene domains were of single-crystalline nature with their domain sizes predetermined throughout seed interspacing. Density functional theory calculations suggested that a self-terminated growth mechanism can be applied for the related graphene growth on h-BN/Cu. In turn, as-constructed field-effect transistor arrays based on such synthesized single-crystalline G/h-BN patterning were found to be compatible with fabricating devices with nice and steady performance, hence holding great promise for the development of next-generation graphene-based electronics.

Morphology, in vivo distribution and antitumor activity of bexarotene nanocrystals in lung cancer

The objective of this study was to develop and evaluate the morphology, biodistribution and antitumor activity of bexarotene nanocrystals delivery system. The morphology was investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscope and bexarotene nanocrystals exhibited the advantages of making the efficacy more steady and durable compared with control group in lung with less cardiac accumulation as shown by biodistribution studies in vivo. In addition, MTT assay, flow cytometry analysis, observation of morphological changes and apoptotic body demonstrated that bexarotene nanocrystals could significantly enhance the in vitro cytotoxicity and induced G1 cycle arrest and apoptosis against A549 cells. Also, bexarotene nanocrystals had significant antitumor activity in mice bearing A549 cell line. This finding was correlated with both in vitro and in vivo. Thereby, the overall results suggest that the bexarotene nanocrystals represent a potential source of medicine, which made bexarotene nanocrystals a promising candidate for the treatment of lung cancer.

Codelivery of paclitaxel and small interfering RNA by octadecyl quaternized carboxymethyl chitosan-modified cationic liposome for combined cancer therapy

Conventional therapeutic approaches for cancer are limited by cancer cell resistance, which has impeded their clinical applications. The main goal of this work was to investigate the combined antitumor effect of paclitaxel with small interfering RNA modified by cationic liposome formed from modified octadecyl quaternized carboxymethyl chitosan. The cationic liposome was composed of 3β-[N-(N', N'-dimethylaminoethane)-carbamoyl]-cholesterol, dioleoylphosphatidylethanolamine, and octadecyl quaternized carboxymethyl chitosan. The cationic liposome properties were characterized by Fourier transform infrared spectroscopy, dynamic light scattering and zeta potential measurements, transmission electron microscopy, atomic force microscopy, and gel retardation assay. The cationic liposome exhibited good properties, such as a small particle size, a narrow particle size distribution, a good spherical shape, a smooth surface, and a good binding ability with small interfering RNA. Most importantly, when combined with paclitaxel and small interfering RNA, the composite cationic liposome induced a great enhancement in the antitumor activity, which showed a significantly higher in vitro cytotoxicity in Bcap-37 cells than liposomal paclitaxel or small interfering RNA alone. In conclusion, the results indicate that cationic liposome could be further developed as a codelivery system for chemotherapy drugs and therapeutic small interfering RNAs.

Highly efficient in vitro biosynthesis of silver nanoparticles using Lysinibacillus sphaericus MR-1 and their characterization

Silver nanoparticles (AgNPs) have been widely used in diverse fields due to their superior properties. Currently the biosynthesis of AgNPs is in the limelight of modern nanotechnology because of its green properties. However, relatively low yield and inefficiency diminish the prospect of applying these biosynthesized AgNPs. In this work, a rapid mass AgNP biosynthesis method using the cell-free extract of a novel bacterial strain, Lysinibacillus sphaericus MR-1, which has been isolated from a chemical fertilizer plant, is reported. In addition, the optimum synthesis conditions of AgNPs were investigated. The optimum pH, temperature, dosage, and reaction time were 12, 70 °C, 20 mM AgNO₃, and 75 min, respectively. Finally, AgNPs were characterized by optical absorption spectroscopy, zeta potential and size distribution analysis, x-ray diffraction, electron microscopy, and energy-dispersive x-ray spectroscopy. The results revealed that these biosynthesized AgNPs were bimolecular covered, stable, well-dispersed face centered cubic (fcc) spherical crystalline particles with diameters in the range 5-20 nm. The advantages of this approach are its simplicity, high efficiency, and eco-friendly and cost-effective features.

Acute oral toxicity evaluations of some zinc(II) complexes derived from 1-(2-salicylaldiminoethyl)piperazine Schiff bases in rats

The current study described the synthesis and the in vivo acute oral toxicity evaluations in Sprague Dawley rats. The compounds were characterized by elemental analyses, LC-MS, FTIR, ¹H NMR, ¹³C NMR and UV-visible spectroscopy. In the acute toxicity study, a single administration of the compounds was performed orally to the rats at the single doses of 2000 mg/kg and they were then monitored for possible side effects, mortality or behavioral changes up to 14 days. The serum level of aspartate (AST), alanine aminotransferases (ALT), alkaline phosphate (ALP), triglyceride, high density lipoprotein (HDL), immunoglobulins (GAM) and the C-reactive proteins did not significantly change. The hematological indices white blood cells (WBC), haematocrit (HCT), red blood cells (RBC), mean corpuscular volume (MCV), mean corpuscular haemoglobin concentration (MCHC), and mean corpuscular hemoglobin (MCH) were within the normal range. The renal function indices examined were also within the reference range. Generally, the compounds exhibited low toxic effects as required for further in vivo therapeutic studies.