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Focal adhesions (FAs) transmit force and mediate mechanotransduction between cells and the matrix. Previous studies revealed that integrin-transmitted force is critical to regulate FA formation. As vinculin is a prominent FA protein implicated in integrin tension transmission, this work studies the relation among integrin tensions (force), vinculin (protein), and FA formation (structure) by integrin tension manipulation, force visualization and vinculin knockout (KO). Two DNA-based integrin tension tools are adopted: tension gauge tether (TGT) and integrative tension sensor (ITS), with TGT restricting integrin tensions under a designed Ttol (tension tolerance) value and ITS visualizing integrin tensions above the Ttol value by fluorescence. Results show that large FAs (area >1 µm2) were formed on the TGT surface with Ttol of 54 pN but not on those with lower Ttol values. Time-series analysis of FA formation shows that focal complexes (area <0.5 µm2) appeared on all TGT surfaces 20 min after cell plating, but only matured to large FAs on TGT with Ttol of 54 pN. Next, we tested FA formation in vinculin KO cells on TGT surfaces. Surprisingly, the Ttol value of TGT required for large FA formation is drastically decreased to 23 pN. To explore the cause, we visualized integrin tensions in both wild-type and vinculin KO cells using ITS. The results showed that integrin tensions in FAs of wild-type cells frequently activate ITS with Ttol of 54 pN. With vinculin KO, however, integrin tensions in FAs became lower and unable to activate 54 pN ITS. Force signal intensities of integrin tensions reported by 33 and 43 pN ITS were also significantly reduced with vinculin KO, suggesting that vinculin is essential to transmit high-level integrin tensions and involved in transmitting intermediate-level integrin tensions in FAs. However, the high-level integrin tensions transmitted by vinculin are not required by FA formation.
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Adhesiones Focales , Integrinas , Integrinas/metabolismo , Adhesiones Focales/metabolismo , Adhesión Celular , Vinculina/metabolismo , Mecanotransducción CelularRESUMEN
In addition to their adjustable functionality, structural tunability, and compositional tunability, metal-organic frameworks (MOFs), often known as MOFs, are a distinct form of crystalline porous material. When reduced to two dimensions, ultrathin layers of MOF retain more of its fantastic external features, which is beneficial for a variety of technological applications. Due to their ultrathin atomic-level thickness, easily modifiable structure, and huge surface area, 2D MOF nanosheets and nanocomposites have been the subject of significant research. MOFs are considered intriguing materials for removing toxic contaminants among the novel technologies taken into account in water remediation processes because they exhibit numerous qualities that make them advantageous in water treatment: large surface area, easily functionalizable cavities, a few stable in water, large-scale synthesis, etc Nowadays, water pollution is a rising environmental concern that must be addressed. Due to their special qualities, which include chemical activities, a variety of functionalities, excellent stability, and the ability to be modified for the detection or adsorption of particular molecules, MOFs are widely used in detecting and removing contaminants from water. This review explores most recent wastewater treatment advancements (WWT) using the 2D MOFs mechanism.
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Worldwide, dyes are significant pollutants present in water because of their huge consumption for industrial purposes. These dyes as pollutants cause serious health issues in human beings and cause the loss of aquatic biodiversity. So, remediation of pollutants like dyes from wastewater is the need of the hour. In the present study, we greenly synthesizedSpirulina-mediated titanium oxide nanoparticles (STONPs) for the adsorptive remediation of methyl orange (MO) (anionic) and malachite green (MG) (cationic) dyes. The characterization of STONPs was performed by Field emission scanning electron microscopy (FESEM) with EDX, FT-IR, XRD, Zeta Potential and particle size analyzer, Raman spectroscopy, and UV-vis. The various parameter effects like pH, nano-adsorbent dose, the concentration of dye, contact time, and temperature were also examined. Adsorption isotherms like Langmuir, Freundlich, and Temkin, and Kinetics models like Elovich Model, Pseudo 1st, intraparticle diffusion model (IPDM), Pseudo 2nd order, and the thermodynamic model were applied for a stronger interpretation. Theqmaxattained utilizing the Langmuir adsorption model was 272.4795 mg g-1and 209.6436 mg g-1for MO and MG correspondingly. The regeneration study of synthesized nanomaterials up to five cycles was also done. We found that greenly synthesized STONPs have great potential for adsorptive remediation for both MG and MO dyes.
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Contaminantes Ambientales , Nanopartículas , Humanos , Colorantes , Adsorción , Espectroscopía Infrarroja por Transformada de Fourier , Cationes , Extractos VegetalesRESUMEN
Bio-nanotechnology is one of the new and sound techniques that have various advantages over conventional methods of wastewater treatment. The utilization of nanomaterials like nanoparticles for wastewater treatment is emerging field of research. Both physical and chemical methods can be used for nanoparticle synthesis, but synthesis based on algae (biological method) has numerous advantages over others as it is environmentally friendly and sustainable. Top-down and bottom-up are the two approaches used for nanoparticle synthesis, generally, bio-reduction (bottom-up approach) is used to synthesize nanoparticles. Nanoparticles can be synthesized inside the cell of algae called intracellular synthesis and outside on the surface of the cell called extracellular synthesis. Temperature, pH, and reaction time are some of the factors that can influence the synthesis, size, and properties of nanoparticles. Characterization of nanoparticles is carried out with the help of the techniques like UV-visible spectroscopy (UV-vis), x-ray diffraction, Fourier transfer infrared spectroscopy, etc. Algal nanoparticles are highly efficient in the remediation of contaminants like heavy metals and dyes from wastewater. In the present review, the utilization of algal nanoparticles for wastewater treatment containing contaminants like heavy metals, and dye, and various methods of synthesis of nanoparticles from algae are discussed. Moreover, the challenges and opportunities present in this field are also highlighted. As this field is in its initial stage, therefore, a lot of research gaps are present, which can only be filled by further new research.
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Nanopartículas del Metal , Metales Pesados , Nanopartículas , Nanoestructuras , Aguas Residuales , Nanopartículas/química , Nanotecnología , Nanopartículas del Metal/químicaRESUMEN
Globally, wastes from agricultural and industrial activities cause water pollution. Pollutants such as microbes, pesticides, and heavy metals in contaminated water bodies beyond their threshold limits result in several diseases like mutagenicity, cancer, gastrointestinal problems, and skin or dermal issues when bioaccumulated via ingestion and dermal contacts. Several technologies have been used in modern times to treat wastes or pollutants such as membrane purification technologies and ionic exchange methods. However, these methods have been recounted to be capital intensive, non-eco-friendly, and need deep technical know-how to operate thus, contributing to their inefficiencies and non-efficacies. This review work evaluated the application of Nanofibrils-protein for the purification of contaminated water. Findings from the study indicated that Nanofibrils protein is economically viable, green, and sustainable when used for water pollutant management or removal because they have outstanding recyclability of wastes without resulting in a secondary phase-pollutant. It is recommended to use residues from dairy industries, agriculture, cattle guano, and wastes from a kitchen in conjunction with nanomaterials to develop nanofibrils protein which has been recounted for the effective removal of micro and micropollutants from wastewater and water. The commercialization of nanofibrils protein for the purification of wastewater and water against pollutants has been tied to novel methods in nanoengineering technology, which depends strongly on the environmental impact in the aqueous ecosystem. So, there is a need to establish a legal framework for the establishment of a nano-based material for the effective purification of water against pollutants.
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Tecnología Química Verde , Nanotecnología , Contaminación del Agua , Purificación del Agua , Proteínas/química , Aguas Residuales , Purificación del Agua/métodos , Tecnología Química Verde/métodos , Nanofibras/química , Hidrogeles/químicaRESUMEN
In this study, we used radical polymerization to create poly (N-isopropyl acrylamide)-co-poly (sodium acrylate) [PNIPAM-co-PSA] hydrogels and analyzed the resulting products. N, N'-Methylenebisacrylamide was employed as a cross-linker, ammonium persulfate as an initiator, and N,N'-isopropyl acrylamide and sodium acrylamide as monomers. Structural analysis was measured by using FT-IR. Indeed, SEM analysis was used to characterize the morphological structure of the hydrogel. Studies on swelling were also done. The Taguchi approach was used to study and assess the adsorption studies of the hydrogels for the efficient removal of malachite green and methyl orange. For the optimization, a central composite surface methodology was applied. The effect of several parameters, including adsorbent dosage, pH, initial dye concentration, temperature, time, and mixing speed, was examined using the Taguchi technique, and the primary factors were chosen and examined using the central composite surface methodology. It was discovered that MG dye's (cationic) removal efficiency was higher than that of MO dye's (anionic). The results suggest that [PNIPAM-co-PSA] hydrogel can be used as an effective, alternative and promising adsorbent to be applied in the treatment of effluents containing the cationic dyes from wastewater. The synthesis of hydrogels provides a suitable recyclability platform for the adsorption of cationic dyes and allows for their recovery without the use of powerful reagents.
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In this study, polyurethane (PU)-based xerogels were synthesized by using the biobased polyol derived from chaulmoogra seed oil. These polyol was used for the preparation of PU xerogels using methylene diphenyl diisocyanate hard segment and polyethylene glycol (PEG6000) as soft segment with 1,4-diazabicyclo[2, 2, 2]octane as catalyst. Tetrahydrofuran, acetonitrile and dimethyl sulfoxide were used as the solvents. Nanocellulose (5 wt %) prepared from bagasse were added as filler, and the obtained composite xerogels were evaluated for chemical stability. The prepared samples were also characterized by using SEM and FTIR. Waste sugarcane bagasse nanocellulose proved as a cheap reinforcer in the xerogel synthesis and for the adsorption of Rhodamine-B dye from the aqueous solution. The factors that affect the adsorption process have been studied including the quantity of the adsorbent (0.02-0.06 g), pH (6-12), temperature (30-50) and time (30-90). Central composite design for four variables and three levels with response surface methodology has been used to get second-order polynomial equation for the percentage dye removal. RSM was confirmed by the measurement of analysis of variance. Increase in the pH and quantity of the adsorbent was found to increase the sorption capacities of the xerogel (NC-PUXe) towards rhodamine B, maximum adsorption.
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PA-KNNT-P(VDF-HFP) composite films were synthesized using facile solution casting technique. Due to their wide range of applications in dielectric and electrical systems, phosphonic acid (PA)-modified tantalum-doped potassium sodium niobate (KNNT)-polyvinylidene fluoride co-hexafluoropropylene P(VDF-HFP) composite films have piqued the interest of academic researchers. Microstructural analysis showed that PA layers incorporated onto the KNNT particles within the polymer matrix. The PA-KNNT-P(VDF-HFP) composite exhibited improved dielectric and electrical performance over a broad range of frequency, and the value of the dielectric constant of the P(VDF-HFP) composites is improved by ≈119 over the P(VDF-HFP) matrix at a filler loading 19 wt.%. Moreover, PA-KNNT-P(VDF-HFP) composite also reveals higher dielectric constant (≈ 119) and AC conductivity than P(VDF-HFP)-KNNT composites, while maintaining suppressed dielectric loss ([Formula: see text] at 102 Hz). It is also observed that the PA-KNNT-P(VDF-HFP) composite exhibited an insulator-conductor transition with a percolation threshold of fKNNT = 13.4 wt.%. As a result of their exceptional dielectric and electrical characteristics, PA-KNNT-P(VDF-HFP) composites have the potential to find exciting practical applications in a variety of electronic domains.
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The intracellular physical parameters i. e., polarity, viscosity, fluidity, tension, potential, and temperature of a live cell are the hallmark of cellular health and have garnered immense interest over the past decade. In this context, small molecule organic fluorophores exhibit prominent useful properties including easy functionalizability, environmental sensitivity, biocompatibility, and fast yet efficient cellular uptakability which has made them a popular tool to understand intra-cellular micro-environmental properties. Throughout this discussion, we have outlined the basic design strategies of small molecules for specific organelle targeting and quantification of physical properties. The values of these parameters are indicative of cellular homeostasis and subtle alteration may be considered as the onset of disease. We believe this comprehensive review will facilitate the development of potential future probes for superior insight into the physical parameters that are yet to be quantified.
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Colorantes Fluorescentes , Orgánulos , ViscosidadRESUMEN
Face shield are the unmistakable plastic gatekeepers secures eyes and face, simpler to wear and a group of specialists state face shields may supplant masks as an increasingly agreeable and progressively successful obstacle to COVID-19. Face shields are useful in stopping respiratory droplets from speading from the wearer to others. The droplets, which come into contact with the shield, are quickly spread over a large area, both transversely and vertically, over the shield, but with a shrinking concentration of droplets, as opposed to face masks, which appear to slide under the nose of the wearer or, worse, collapse entirely off the shield. Hence, a face- shield can be considered as personal protective equipment (PPE), which is a first line of resistance, utilized by the clinicians and forefront health workers for protection against the infectious body fluid and aerosols. Face-shields are mainly fabricated using polycarbonate material, because of their excellent optical transparency in UVA-visible-IR spectrum and mechanical properties. The goal of this article is to provide researchers working in the same area, as well as health and industrial staff, with a detailed analysis of the usage of face shields against bioaerosols and the need for personal security. The reviews main focus on the background of the face shield, provide assistance in the selection, its design and structure, applications, advantages and disadvantages. Lastly, people's view about the usage of face shield as it becomes an essential part of human beings like an accomplice during this current pandemic situation.
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Drugs re-purposing due to COVID-19 virus has declared a number of useful candidates for treatment and prevention of the virus. Ivermectin (IVM) has gained much popularity due to a strong background of magical applications against a broad spectrum of pathogens. The in- vitro studies of ivermectin have shown promise, the thorough clinical trials of its efficacy in the treatment and prevention of SARS-CoV-2 are still warranted. Useful strategies for analyzing projected use of IVM in human coronaviruses might be developed. It may be done by concluding ongoing clinical trials and culturing lessons from IVM usage in veterinary practice. The potential toxicity and careful dosage analyses are urgently required before declaring it as an anti-SARS-CoV-2 drug candidate. This manuscript overviews the background and potential threats associated with the off-label use of IVM as prophylactic drug or treatment option against COVID-19 virus.
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The uncontrollable outbreak of the novel coronavirus (COVID-19) rapidly affected almost 230 countries across the world and territories since last year'2020 and its transmission mainly due to respiratory droplets. To fight and protect against micron dimension (~1.4 µm) corona virus the usage of disposable medical masks is one and only trivial option for patients, doctors, health employers and in fact mandatory for kids to senior citizens, as well as public places in a risky environment. Ordinary medical masks unable to self-sterilize in order to recycle for other appliances resulting further destroying impact of societies high economic and environmental costs. To minimize this global pandemic issue this proposal explores novel mechanism for further commercialization of surgical mask of photo-thermal and self-cleaning functionalization. Indeed, depositing few layer ultra-thin graphene coating onto low-melting temperature non-woven mask by tempering a dual mode laser induced mechanism. Incoming aqueous droplets are bounced off due the super-hydrophobic states were treated on the mask surface. Superficial hydrophobic surface yields an advanced safety towards approaching respiratory droplets. Due to the huge absorption coefficient capability of the sunrays activated laser-induced mask may rapidly boost temperature exceeds 85ºC under sunlight illumination, causes making the mask reusable after sunlight distillation. For SARS/coronavirus/ aerosolized bacteria, laser induced graphene mask is a recent breakthrough in superior antibacterial capacity. Furthermore, cost-effective and ultra-thin layered mask formulation recycled directly utilizes solar-driven desalination with remarkable self-exclusion performance for indelible usability. Featured review article, deals with remarkable achievements from forthcoming experimentation which may be inspired with layered mask designing by more progressive materials.
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Early detection is the first step in the fight against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Therefore, an efficient, rapid, selective, specific, and inexpensive SARS-CoV-2 diagnostic method is the need of the hour. The reverse transcription-polymerase chain reaction (RT-PCR) technology is massively utilized to detect infection with SARS-CoV-2. However, scientists continue to strive to create enhanced technology while continually developing nanomaterial-enabled biosensing methods that can provide new methodologies, potentially fulfilling the present demand for rapid and early identification of coronavirus disease 2019 (COVID-19) patients. Our review presents a summary of the recent diagnosis of SARS-CoV-2 of COVID-19 pandemic and nanomaterial-available biosensing methods. Although limited research on nanomaterials-based nanosensors has been published, allowing for biosensing approaches for diagnosing SARS-CoV-2, this study highlights nanomaterials that provide an enhanced biosensing strategy and potential processes that lead to COVID-19 diagnosis.
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Integrin-transmitted cellular forces have rich spatial dynamics and are vital to many cellular functions. To advance the sensitivity and spatial resolution of cellular force imaging, we developed a force-activatable emitter reporting single-molecular tension events and the associated cellular force nanoscopy (CFN). Immobilized on a surface, the emitters are initially dark (>99.8% quenched), providing a low fluorescence background despite the high coating density (>2000/µm2) required for sampling cellular force properly. The emitters fluoresce brightly once switched on by integrin tensions and can be switched off by photobleaching, enabling continuous real-time imaging of integrin molecular tensions in live cells. With multiple cycles of molecular tension imaging and localization, CFN reproduces cellular force images with 50 nm resolution. Applied to both migratory cells and stationary cells, CFN revealed ultranarrow distribution of integrin tensions at the cell leading edge, and showed that force distribution in focal adhesions (FAs) is off-centered and FA size-dependent.
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Integrinas/química , Fenómenos Biomecánicos , HumanosRESUMEN
In this work, a selective chemiresistive gas sensor for carbon dioxide gas detection at room temperature (â¼25 °C) was successfully fabricated, where ruthenium-decorated tungsten disulfide (Ru@WS2) quantum dots (QDs) have been used as the sensing material. A mixed solvent of lithium hydroxide (LiOH · H2O) and N-methyl-2-pyrrolidone (NMP) was used to obtain the Ru-decorated WS2 QDs from the exfoliated WS2 nanoflakes. Then, the prepared WS2 QDs and Ru@WS2 QDs were confirmed using different material characterization techniques. The gas sensors were prepared by spraying the WS2 QDs and Ru@WS2 QDs on gold interdigitated electrodes (IDE), and were then exposed to various concentrations of CO2 gas in dry air conditions. Also, the effect of humidity on both sensors in 5000 ppm CO2 gas has been studied. The Ru@WS2 QD based sensor showed superior sensitivity and good selectivity to CO2 gas in comparison with isopropanol, acetone, ethanol, methanol and benzene at room temperature than the WS2 QD. The sensor showed an increase in resistance when exposed to CO2 gas ranging from 500 to 5000 ppm, indicating p-type characteristics. The Ru@WS2 QD shows less effects at different humid conditions compared to WS2 QD as a CO2 gas sensor.
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Transition metal dichalcogenides (TMDs) materials are from the two-dimensional (2D) materials family and have many benefits, comprising high carrier mobility and conductivity, high optical transparency, outstanding mechanical flexibility, and chemical stability, and are also favorable gas sensing materials because of their high surface-area-to-volume ratio. Nevertheless, their low gas-sensing performance in terms of low response, partial recovery, and poor selectivity obstruct the apprehension as high-performance 2D TMDs gas sensing materials. At this time, we explain the enhancement in gas-sensing performance of molybdenum disulfide (MoS2) nanoflakes (NF) by decorating with Lanthanum (La) at room temperature (25 °C). Our experiments show that the dynamic sensing response of the La decorated few-layered MoS2 (La@MoS2) sensor increases by â¼6 times than the pristine few-layered MoS2, which positions it first-ever reported values for NO2 gas detection. The sensitivity of the MoS2 and La@MoS2 found 0.627 and 3.346 ppm-1, respectively, towards NO2 gas. It is noteworthy that La has introduced to MoS2, and its selectivity towards the volatile organic compounds (VOCs) and other toxic gases improved drastically. Our outcomes show that the suggested method represents a successful approach for improving the gas sensing response of 2D TMDs sensors.
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A new class of solvatochromic, robust, and multifunctional fluorescent probes derived from indoline is presented. Specificity of mitochondria targeting was achieved and utilized for probing polarity under normal and apoptotic conditions. A large Stokes shift, high quantum yield, thermal, photochemical, and pH stability, tolerance to buffer compositions, and a bioconjugation tool-kit make it a promising candidate for live-cell fluorescence imaging.
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Diagnosis and therapy exploiting overexpressed receptors on the cell surface is one important strategy in medicine. Determination of the over expression level of a particular receptor is prerequisite for it to be of clinical use. Differentiation between FR-positive (FR=folate receptor) and -negative cells via fluorescence microscopy using a substrate mimetic fluorophore is presented in this work. The strategy adopted here is not the classical FA-conjugated (FA=folic acid) fluorescent probe but a small and environment-sensitive pterin-based (pterin is part of folate, i.e., vitaminâ B9) fluorescent probe. Electronically diverse pterin-based fluorescent probes have been designed and synthesized to understand the effect of the binding environment on the receptor-substrate interactions. By utilizing steady-state UV/Vis and fluorescence along with time-resolved fluorescence spectroscopy, the effects on the electronic and acid-base properties of the substrate were investigated. Evidently, one synthesized probe showed FA-mimicking behavior with strong binding interaction with FR.
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A class of highly sensitive chemiresistive sensors is developed for methanol (MeOH) vapor detection in ambient atmosphere by introducing conductive nanofillers like carbon black, multi-wall carbon nanotubes, and reduced graphene oxide into sulfonated poly(etherimide) (PEI)/liquid crystal polymer (LCP) composite (sPEI-LCP). Polar composites are prepared by a sulfonation process for instantaneous enhancement in adsorption capability of the sensing films to the target analyte (MeOH). Sensing properties exhibit that polymer composite-based fabricated sensors are efficient for the detection of different concentration of methanol vapor from 300-1200 parts-per-million (ppm) at room temperature. The incorporation of nanofiller induces the dramatic change in sensing behavior of base composite film (sPEI-LCP). Thus, less mass fraction of nanofillers (i.e. 2 wt%) influences the nonlinear sensing behavior for the entire range of methanol vapor. The simple method and low fabrication cost of the prepared sensor are compelling reasons that methanol vapor sensor is suitable for environmental monitoring.
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Novel synthesis and properties of versatile CdS nanostructures (e.g., Nano-brush, nano-cube, nanosphere) dispersed liquid crystals application in chemical friendly medium exploring this article. Most recent studies, CdS nano-wire brush with the stacking fault structures were hydrothermally synthesized through a dissolution-recrystallization approach in concentrated ammonia solvent in one step solution, for the first time. Those structures-property relations with respect to ferroelectric hydrogen-bonded liquid-crystalline complex (HBLC; AC + 5BAO) controlled and efficient formation of surface relief nanostructures. A successful attempt has been made to form hydrogen bonding between CdS nanostructures and supramolecular LC with pn-alkyloxy benzoic acids (n-OBA). The formation of an inter-H-bond is evinced through FTIR study, as well as Gaussian simulation also ensures complete formation of intermolecular hydrogen bond optimized geometry. In contrast, a new sensitive response of smectic G ordering observed in this series is investigated by constructing a phase diagram obtained from two binary mixtures of CdS nanostructures influenced by homogeneous liquid crystals. Temperature-dependent dielectric relaxation, tilt angle, electro-optical switching measurements allow for monitoring very unique and useful behavior in that the polarization of the emission from the semiconductor nanostructures can be controlled by an external bias. It reveals electrically tunable interaction of the composites may allow for engineering of practical electro-optic switchable device.