Bottle Brush Research Articles

Preparation of polyelectrolyte based on bottle brush Polyethylene glycol‐Poly(N‐isopropylacrylamide) copolymers

AbstractThe increased demand for high energy‐density batteries led to using lithium metal (Li) anode. However, safety issues associated with Li anode encouraged the researchers to use less reactive and safer electrolytes with higher electrochemical stability. High ionic conductivity (σ), wider electrochemical stability window, and higher mechanical strength alongside the ability to self‐heal possible structural damages were at the center of focus for developing efficient solid electrolytes. In this regard, we developed a group of solid polymer electrolytes (SPEs) with high σ and electrochemical stability. In this regard, bottle brush polyethylene glycol (bbPEG) was synthesized using a chain transfer reaction. Polynipaam (PNIPAAM) blocks were also incorporated into the structure to prepare a block copolymer based on PNIPAM‐bbPEG‐PNIMAM represented by the ABA structure. The block copolymer was then blended with polyvinylidene fluoride (PVDF) with the block copolymer to PVDF weight ratio of 7:2% and 25% bis(trifluoromethane) sulfonamide (TFSI) salt was added and the final mixture was UV‐cured. The results indicated that the final SPE possessed high ionic conductivity with a relatively high lithium‐ion transference number () of 0.416 and the σ of 1.265 × 10−5 S/cm at 25°C.

TAAR1 and 5-HT1B receptor agonists attenuate autism-like irritability and aggression in rats prenatally exposed to valproic acid

Despite the rising prevalence of autism spectrum disorder (ASD), there remains a significant unmet need for pharmacotherapies addressing its core and associative symptoms. While some atypical antipsychotics have been approved for managing associated irritability and aggression, their use is constrained by substantial side effects. This study aimed firstly to develop behavioral measures to explore frustration, irritability and aggression phenotypes in the rat prenatal valproic acid (VPA) model of ASD. Additionally, we investigated the potential of two novel mechanisms, 5-HT1B and TAAR1 agonism, to alleviate these behaviors. Male offspring exposed to prenatal VPA were trained to achieve stable performance on a cued operant task, followed by pharmacological assessment in an operant frustration test, bottle brush test and resident intruder test. VPA exposed rats demonstrated behaviors indicative of frustration and irritability, as well as increased aggression compared to controls. The irritability-like behavior and aggression were further exacerbated in animals previously experiencing a frustrative event during the operant test. Single administration of the 5-HT1B agonist CP-94253 or TAAR1 agonist RO5263397 attenuated the frustration-like behavior compared to vehicle. Additionally, both agonists reduced irritability-like behavior under both normal and frustrative conditions. While CP-94253 reduced aggression in the resident intruder test under both conditions, RO5263397 only produced effects in rats that previously experienced a frustrative event. Our study describes previously uncharacterized phenotypes of frustration, irritability, and aggression in the rat prenatal VPA model of ASD. Administration of selective TAAR1 or 5-HT1B receptor agonists alleviated these deficits, warranting further exploration of both targets in ASD treatment.

Nanophase Segregation Drives Heterogeneous Dynamics in Amphiphilic PLMA‐b‐POEGMA Block‐Copolymers with Densely Grafted Architecture

AbstractThe self‐assembly and dynamics of amphiphilic diblock copolymers composed of densely grafted poly(oligo ethylene glycol methacrylate) (POEGMA) and poly(lauryl methacrylate) (PLMA) by means of calorimetry, small‐angle X‐ray scattering (SAXS), and dielectric spectroscopy are investigated. It is reported that the inherent immiscibility between the parent homopolymers, combined with the increased molar mass, results in strong segregation, maintained up to elevated temperatures (i.e., T = 423 K). SAXS reveals that well‐separated POEGMA and PLMA domains self‐assemble into spheres with bicontinuous cubic packing and in lamellar nanostructure in copolymers with respective compositions of 16 and 52 wt.% PLMA. This strong segregation enables the weak crystallization/melting of the short ethylene glycol chains. Additionally, molecular dynamics are investigated through isothermal dielectric and calorimetry measurements. The segmental dynamics (i.e., Tg‐related) of POEGMA and PLMA closely resemble that found in respective homopolymers, implying heterogeneous dynamics. In the glassy state, the local motions of the POEGMA side chains predominantly govern the observed secondary processes in the copolymers. The results on the heterogeneous dynamics in the current amphiphilic diblock copolymers with the densely grafted architecture are compared and contrasted with copolymers having a bottle–brush architecture lacking the amphiphilic nature.

Review on Callilstemon citrinus: Recent Approaches in Novel Drug Delivery System

Callistemon citrinus is an ornamental plant. The plant is commonly originated in subtropical and tropical region. C.citrinus, commonly referred to as bottlebrush, is a member of myrtaceae family. Active ingreadients such as 1, 8-cineole, triterpenoids, α-pinenes, eucalyptol, tannis, alkaloids, flavonoids, saponins, phytosterol etc. are mostly found in the various plant sections. It is generally use in traditional, folk and herbal medicine as a water accent, anticough, antibronchtits, insecticide and treatment of diarrhoea, dysentery and rheumatism. This article aims to provide a comprehensive review on the pharmacological aspects and recent novel approaches of callistemon citrinus highlight methodologies, applications, and potential contributions of this natural extract in enhancing drug delivery, offering insights into its pharmacological potential and future prospects in the field. The primary objective to collect updated information about effectiveness of the plant extract in addressing specific health issues and its potential as a therapeutic effect using novel drug delivery systems. Innovative methods explored in delivering the plant extract, such as Nano formulations in various diseases i.e. Antifungal properties, acute toxicity, brine shrimp cytotoxicity and relaxant activity, antimicrobial Activity etc. The methods improve therapeutic efficacy and reduces side effects by optimizing the delivery of bioactive compounds from callistemon citrinus. Keywords: Callistemon citrinus, Bottle brush, Pharmacological activities, Novel Drug Delivery Systems, Isolated compounds.

Specialized ovipositor sensilla of Cretaceous wasps (Insecta: Hymenoptera) possibly reveal a unique way of host detection.

Insects have evolved complex sensory systems that are important for feeding, defence and reproduction. Parasitoid wasps often spend much time and effort in searching for concealed hosts with the help of specialized sensilla. However, the early evolution of such behaviour and sensilla is poorly known. We describe two fossil female wasps, †Tichostephanus kachinensis sp. nov. and †Tichostephanus longus sp. nov., from mid-Cretaceous Kachin amber. Phylogenetic analyses based on morphological data retrieved †Tichostephanus as deeply nested within Evanioidea and closely related to extant Gasteruptiidae and Evaniidae. Both of these Cretaceous wasps possess features, e.g. coronal tubercles and flexible ovipositor sheaths, that indicate that they might have laid eggs in wood where their larvae possibly parasitized insect larvae. They have a peculiar and unique 'bottle brush' of sensilla close to the apex of their ovipositor sheaths, which has not been observed in any extant parasitoid wasps. These sensilla comprise many regularly arranged plate-shaped setae, attached in relatively large sockets and with rows of longitudinal ridges. Such specialized sensilla perhaps served to enhance the ability to detect hosts inside wood.

Photoactivatable poly(2-oxazoline)s enable antifouling hydrogel membrane coatings

In recent years, hydrophilic poly(2-oxazoline)s have been examined as an alternative polymer to poly(ethylene glycol) (PEG) with added stability and chemical versatility. They show excellent anti-fouling properties and, like PEG, are of interest in many fields where bio-inertness or anti-adhesiveness are important such as for medical devices, tissue engineering, biosensors, or drug delivery carriers. Surprisingly few studies have utilized this polymer class for the preparation of anti-fouling membranes. Here we describe a new termination reaction of the living cationic ring-opening polymerization of 2-oxazolines in which a benzophenone group is introduced as a photoactivatable terminal head group of poly(2-oxazoline)s. Using 4-vinylbenzyl chloride as initiator, heterotelechelic poly(2-methyl-2-oxazoline) (PMOXA) macromonomers were synthesized and copolymerized with hydroxyl-functional PMOXA macromonomers to yield photoactivatable PMOXA-based prepolymer bottle brushes. Likewise, star-PMOXAs were synthesized by using a trifunctional initiator. Photoactivatable PMOXA prepolymers allowed us to readily form anti-fouling hydrogels by a simple and versatile CH-insertion cross-linking (CHic) process. Hydrogels were applied to poly(ether sulfone) ultrafiltration membranes as pore coating and the pure water permeance (PWP) was investigated as a function of hydrogel architecture and cross-link density. Anti-fouling hydrogel pore-coated membranes having PWPs on the order of hundred kg·m−2·h−1·bar−1 were obtained.

Abundance, Morphological Features, and Economic Values of Selected Tree Species in Company Graden of Saharanpur District, Uttar Pradesh, India

This study aimed to assess the abundance, morphological features, and economic values of selected tree species (Mango, Eucalyptus, and Bottle brush) within Company Garden of Saharanpur, Uttar Pradesh, India. Through systematic survey and analysis, the results showed that Eucalyptus emerged as the most abundant species, constituting 40% of the tree population. Mango trees, comprising approximately 35% of the population, were out for their economic importance and cultural significance. While their cultivation offers economic benefits, their influence on biodiversity and soil health warrants careful evaluation, particularly in the context of human cultivation practices. Bottle brush trees, though least abundant at 15%, contribute uniquely to the ecosystem by providing ornamental value and potential wildlife habitat. Their ecological contributions emphasize the importance of preserving biodiversity within the ecosystem. On the other hand, analysis of morphological and economic features highlighted the distinct characteristics of each species. Eucalyptus, with its remarkable height and girth, proves valuable for timber production and ecological functions such as erosion control. Mango trees, prized for fruit production and shade provision, play a crucial role in agroforestry contexts. While Bottle brush trees may not be extensively utilized for timber, their ornamental value and ecological contributions are noteworthy. Overall, the study provides valuable insights into the abundance, morphological characteristics, and ecological significance of tree species within the Company Garden.

Comparison of Polypentenamer and Polynorbornene Bottlebrushes in Dilute Solution.

Bottlebrush (BB) polymers were synthesized via grafting-from-atom transfer radical polymerization (ATRP) of styrene on polypentenamer and polynorbornene macroinitiators with matched grafting density (n g = 4) and backbone degrees of polymerization (122 ≥ N bb ≥ 61) to produce a comparative study on their respective dilute solution properties as a function of increasing side chain degree of polymerization (116 ≥ N sc ≥ 5). The grafting-from technique produced near quantitative grafting efficiency and narrow dispersity N sc as evidenced by spectroscopic analysis and ring closing metathesis depolymerization of the polypentenamer BBs. The versatility of this synthetic approach permitted a comprehensive survey of power law expressions that arise from monitoring intrinsic viscosity, hydrodynamic radius, and radius of gyration as a function of increasing the molar mass of the BBs by increasing N sc. These values were compared to a series of linear (nongrafted, N sc = 0) macroinitiators in addition to linear grafts. This unique study allowed elucidation of the onset of bottlebrush behavior for two different types of bottlebrush backbones with identical grafting density but inherently different flexibility. In addition, grafting-from ATRP of methyl acrylate on a polypentenamer macroinitiator allowed the observation of the effects of graft chemistry in comparison to polystyrene. Differences in the observed scaling relationships in dilute solution as a function of each of these synthetic variants are discussed.

Bottlebrush Elastomers with Crystallizable Side Chains: Monolayer-like Structure of Backbones Segregated in Intercrystalline Regions.

Bottlebrush (BB) elastomers with water-soluble side chains and tissue-mimetic mechanical properties are promising for biomedical applications like tissue implants and drug depots. This work investigates the microstructure and phase transitions of BB elastomers with crystallizable polyethylene oxide (PEO) side chains by real-time synchrotron X-ray scattering. In the melt, the elastomers exhibit the characteristic BB peak corresponding to the backbone-to-backbone correlation. This peak is a distinct feature of BB systems and is observable in small- or medium-angle X-ray scattering curves. In the systems studied, the position of the BB peak ranges from 3.6 to 4.8 nm in BB elastomers. This variation is associated with the degree of polymerization of the polyethylene oxide (PEO) side chains, which ranges from 19 to 40. Upon crystallization of the side chains, the intensity of the peak decays linearly with crystallinity and eventually vanishes due to BB packing disordering within intercrystalline amorphous gaps. This behavior of the bottlebrush peak differs from an earlier study of BBs with poly(ε-caprolactone) side chains, explained by stronger backbone confinement in the case of PEO, a high-crystallinity polymer. Microstructural models based on 1D SAXS correlation function analysis suggest crystalline lamellae of PEO side chains separated by amorphous gaps of monolayer-like BB backbones.

Field Study to Assess UASS Mosquito Adulticiding: Methods and Data

Highlights Mosquito adulticiding over operationally relevant areas is feasible using UASS. Wind speed plays an important role in the spray landing position, as expected based on previous studies using CASA. Results are based on both passive and active collectors, including flat cards, rotary impingers, and bottle brushes. Over 1900 total samples were collected in 8 trials, and elevated samplers allowed analysis of the descent of the droplet cloud. Abstract. A spatially extensive experiment was designed to evaluate the effectiveness of Uncrewed Aerial Spray Systems (UASS) in mosquito adulticiding. The practice of adulticiding uses very fine droplets (DV0.5 <50µm). The objective is to fill a volume of air with fine droplets that a flying adult mosquito will encounter in flight. A field program was designed with samplers as far as 500 m downwind from the UASS flight line. A total of over 1900 samples were collected over the course of eight trials. Both passive and active collectors were deployed. Tests were conducted in the early morning and were generally successful in terms of meteorological conditions and data collection. Elevated samplers successfully tracked the descent of the spray cloud, and spray was collected from the most distant samplers. The known dependence of spray movement on wind speed that has been widely observed and codified into label language for Crewed Aerial Spray Aircraft (CASA) was observed. Very low wind speed conditions are problematic for adulticiding in general, and undesirable near-field deposition of adulticiding spray was observed in the data presented here under low wind speed conditions. It needs to be emphasized that much more data needs to be collected before statistically robust conclusions can be drawn. Generally, these data show that UASS can be used to disperse very fine spray droplets over areas representative of operational adulticiding. This paper presents and discusses spray movement and deposition, a second paper is in preparation comparing these data to existing models of spray dispersion and deposition from UASS spraying. A third paper examining mortality from UASS adulticiding has been published. Keywords: Adulticiding, Pesticide drift, UASS Spraying, UAV.

Bottle brush star block copolymer nanoreactors for efficient photooxidation catalysis: effects of chain softness

The bottle brush star polymer, characterized by its super-soft nature, has the remarkable ability to accelerate the photocatalytic activity of the nanoreactor through enhanced diffusion.

Synthesis and morphological control of self-powered broadband photodetector material: A study of bottle brush Co3O4/ZnO heterojunction

Self-powered broadband photodetectors operating in the ultraviolet–visible–near infrared (UV–Vis–NIR) range are pivotal for various applications, including optical communication, military surveillance, multispectral sensing, and environmental monitoring. In this study, we present an innovative approach to fabricate a bottlebrush nanostructure employing the Co3O4/ZnO PN junction. This unique design allows the photodetector to function efficiently without bias condi-tions, providing a versatile platform for a wide range of detection capabilities. The morphology of the photodetector is precisely controlled by manipulating the concentration of the growth solution containing cobalt tetroxide. Specifically, maintaining a concentration of 10 mM results in a well-defined bottlebrush heterojunction that exhibits highly efficient detection performance in the UV–Vis–NIR region. The maximum achievable responsivity (R) and specific detectivity.(D) are noteworthy, reaching values of 103.3 mA W−1 and 1.58 × 1014 Jones, respectively. These findings present a novel strategy for developing broadband photodetectors based on stable, nontoxic, and cost-effective metal oxides, opening new possibilities for advancements in photodetection technology.

Anisotropy in Antimicrobial Bottle Brush Copolymers and Its Influence on Biological Activity

AbstractAntimicrobial polymers are a promising alternative to conventional antibiotics in the fight against antimicrobial resistance. Cationic bottle brush copolymers have shown to be superior to linear topologies in previous studies. Herein, the aspect ratio of such polymers is varied creating differently shaped confined unimolecular structures with varying degrees of side chain mobility. Using reversible addition‐fragmentation chain‐transfer (RAFT) polymerization, bottle brushes are produced in a one‐pot procedure. The morphology is confirmed by atomic force microscopy. The hydrophobicity, as determined via high performance‐liquid chromatography (HPLC) analysis, is drastically influenced by the topology. Using Fourier‐transform infrared (FTIR) spectroscopy, it is found that polymers with a high side chain mobility and increased global hydrophilicity, are less hydrated, and have stronger intramolecular hydrogen bonds. A phase segregated morphology leading to unimolecular micellization is assumed. Biological tests reveal increased antimicrobial activity for such segregated polymers. Their excellent hemocompatibility results in highly selective antimicrobial polymers whose adaptability seems to be a key feature in their excellent performance. This study highlights the tremendous importance of structural control in antimicrobial polymers.

Synthetic Evolution of a Supramolecular Harpooning Mechanism to Immobilize Vesicles at Antifouling Interfaces

AbstractThe immobilization of vesicles has been conceptualized as a method to functionalize biointerfaces. However, the preservation of their integrity post immobilization remains a considerable challenge. Interfacial interactions can cause vesicle rupture upon close surface contact and non‐specific protein adsorption impairing surface functions. To date, immobilization of vesicles has relied solely on either entrapment or prior modification of vesicles, both of which require laborious preparation and limit their applications. This work develops a bioinspired strategy to pin vesicles without prior modification while preserving their intact shape. This work introduces antifouling diblock copolymers and ultrathin surface‐attached hydrogels containing a brush‐like interface consisting of a bottle brush copolymer of N‐(2‐hydroxypropyl) methacrylamide (HPMA) and N‐(3‐methacrylamidopropyl)‐N,N‐dimethyldodecan‐1‐aminiumiodide (C12+). The presence of positive charges generates an attractive force that pulls vesicles toward the surface. At the surface, the amphiphilic properties of the combs facilitate their insertion into the membrane, mimicking the harpooning mechanism observed in antimicrobial peptides. Importantly, the antifouling poly(HPMA) backdrop serves to safeguard the vesicles by preventing deformation and breakage. Using a combination of thermodynamic analysis, surface plasmon resonance, and confocal laser scanning microscopy, this work demonstrates the efficiency of this biomimetic system to capture vesicles while maintaining an antifouling interface necessary for bioapplications.

Persistence Length of PEGMA Bottle Brushes Determined by Pyrene Excimer Fluorescence.

Seven pyrene-labeled poly(oligo(ethylene glycol) methyl ether methacrylate)s (PyEG5-PEGnMAs) were prepared with n = 0, 3, 4, 5, 7, 9, and 19 ethylene glycol units by copolymerizing a small amount of penta(ethylene glycol) 1-pyrenemethyl ether methacrylate with an EGnMA monomer. The conformation of the PyEG5-PEGnMA polymers evolved from a random coil for PyEG5-PEG0MA or poly(methyl methacrylate) to a polymeric bottle brush (PBB) architecture with increasing side chain length. The fluorescence decays of the PyEG5-PEGnMA samples were fitted according to the fluorescence blob model (FBM) whose parameters were used, in combination with the Kratky-Porod equation, to calculate the persistence length of these polymers. The persistence lengths obtained from the PEF experiments were found to increase with the square of the number (NS) of non-hydrogen atoms in the side chain as expected theoretically. The persistence lengths found with the PyEG5-PEGnMA samples in DMF also matched those found earlier for another series of PEGnMA samples labeled with 1-pyrenebutanol. The good agreement found between the persistence lengths obtained with the PEGnMA samples labeled with two different pyrene derivatives illustrates the robustness of the method and its applicability for measuring the unknown persistence length of polydisperse polymer samples.

Preparation of floral calendar of bee flora available in Lamjung district, Nepal

Between March and May 2022, researchers conducted a broad survey in the Lamjung district to ascertain the presence and accessibility of bee-friendly flora to compile a floral calendar. In the PMAMP Bee Zone, 62 respondents were chosen for the interview through a simple random sampling approach, from a pool of 382 registered beekeepers. Primary data collection involved using personal interviews, focus group discussions, and key informant surveys. Secondary data were gathered from publications related to the topic from various institutions. The collected data were then analyzed using IBM SPSS V.26 and Microsoft Excel. Nearly all farmers in the study area kept Apis cerana bees, but due to insufficient irrigation, the crop fields provided limited forage for the bees during certain periods. The lowest number of frames covers by bees was four during the dearth period. Farmers in the Lamjung district did not practice migratory foraging. The majority of the respondents reported an increase in productivity compared to the previous year. However, only 37.1 percent of them cultivated bee flora. The colony carrying capacity of the forage area was not estimated. Additionally, an increase in deforestation was identified as the major problem affecting bee foraging. To address these issues, it was recommended to plant and cultivate perennial trees such as butter trees (Vitellaria paradox), bottle brush (Callistemon speciosus), litchi (Litchi chinensis), sissoo (Dalbergia sissoo), and sunflower (Helianthus annus) with assured irrigation. This approach could ensure year-round forage availability and reduce the need for artificial feeding. The research aimed to explore the current status of honey bee flora and investigate major flora that could be introduced in the study area.

Efficacy of freshwater pearl mussel (Lamellidens marginalis) as a biomonitoring tool for assessing microplastic pollution

The presence of microplastics (MPs) is an emerging concern for aquatic life. The present study investigated the ingestion and absorption of experimental MPs in the internal organ and body tissue of freshwater pearl mussel (Lamellidens marginalis) following exposure for 10 days and using histological procedures. Mussels were exposed to three types of bright color plastics were used such as plastic rope fibers, green PET bottle fragments and brush bristles. A reference group not exposed to MPs was also included. Following exposure, tissues were dissected and embedded in paraffin, and histological sections were examined for the presence of microplastic. Result showed that 31.25% of all the exposed mussels exhibited the ingestion of MPs. Fiber was the highly accumulated MPs followed by filaments. However, none of the mussels showed the ingestion of brush bristles. Accumulation of MPs was the highest for smaller sized categories. Histological observation of mussel’s tissue was also showed the absorption of MPs. The present experiment strongly suggests that the uptake, presence, and potential health impacts of MP should be closely monitored using L. marginalis as bio-monitor organism.

Synthetic Star Nanoengineered Antimicrobial Polymers as Antibiofilm Agents: Bacterial Membrane Disruption and Cell Aggregation.

Antimicrobial resistance has become a worldwide issue, with multiresistant bacterial strains emerging at an alarming rate. Multivalent antimicrobial polymer architectures such as bottle brush or star polymers have shown great potential, as they could lead to enhanced binding and interaction with the bacterial cell membrane. In this study, a library of amphiphilic star copolymers and their linear copolymer equivalents, based on acrylamide monomers, were synthesized via RAFT polymerization. Their monomer distribution and molecular weight were varied. Subsequently, their antimicrobial activity toward a Gram-negative bacterium (Pseudomonas aeruginosa PA14) and a Gram-positive bacterium (Staphylococcus aureus USA300) and their hemocompatibility were investigated. The statistical star copolymer, S-SP25, showed an improved antimicrobial activity compared to its linear equivalent againstP. aeruginosaPA14. The star architecture enhanced its antimicrobial activity, causing bacterial cell aggregation, as revealed via electron microscopy. However, it also induced increased red blood cell aggregation compared to its linear equivalents. Changing/shifting the position of the cationic block to the core of the structure prevents the cell aggregation effect while maintaining a potent antimicrobial activity for the smallest star copolymer. Finally, this compound showed antibiofilm properties against a robust in vitro biofilm model.

Bottle brush sign by 18F-FDG PET/CT in a patient with neurolymphomatosis

Bottle brush sign by 18F-FDG PET/CT in a patient with neurolymphomatosis

ETHNOMEDICINAL STUDIES OF SOME MYRTACEAE PLANTS FROM NANDED REGION OF MAHARASTRA

Nanded is one of the most biodiversity rich region of Maharastra. This area is having deciduous regions known as Kinwat, Mahur and Shita-khandi forest. The regional peoples uses many traditional medicines for the treatments of various diseases. The aim of current research is to survey and documents ethno-medicinal usages of family Myrtaceae. For this data collection many time field visits were given. All the collected data and information were confirmed using available literature. Total six plants of Myrtaceae were reported in the study. Syzygiun cumini (Jamun), Psidium guajava L. (Guava), Eucalyptus globules (Nilgiri) are the common plants reported in survey including Callistemon citrinus ( Bottle brush), Syzygium aromaticum L. (Laong), and Syzygium jambos L. The plants reported in the present study were found to be used by local peoples for the treatments of different aliments.