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Cellulose-based materials are not in short supply and are characterized by relatively low cost. On the other hand, cellulose fibers have a wide range of valuable physical, chemical and mechanical properties that make them indispensable in a number of sectors of the national economy. Along with valuable qualities, natural and artificial cellulose fibers also have some disadvantages that limit their use in technology and in the national economy. These are low resistance to the action of microorganisms, relatively low heat resistance, chemical resistance, flammability, etc., which reduce their service life and limit their scope. One of the ways to eliminate these shortcomings is the modification of natural and artificial macromolecular compounds by chemical and physicochemical methods. Improving the properties of cellulose and its derivatives can be achieved by various modification methods, among which one of the most promising is the radiation-chemical grafting of various monomers. One of the advantages of this method, in comparison with others, is the production of field worlds that are not contaminated with impurities, the presence of which can adversely affect their physicochemical properties. Another advantage is the relative ease of formation of macroradicals necessary to initiate the process of graft copolymerization. Quite a lot of work has been devoted to the radiation grafting of various monomers to cellulose and its derivatives; at present, some of them are beginning to be widely used in the national economy. In the light of the foregoing, the grafting of fluorine-containing monomers, the polymers and copolmers of which have such very valuable and specific properties as high heat resistance, chemical resistance, light resistance, decay resistance and hydrophobicity to cellulose and its derivatives, is of great scientific and practical interest. This work is the synthesis of graft copolymers of cotton cellulose with vinyl fluoride by the radiation-chemical method from the vapor phase, the study of the effect of radiation dose rate, reaction time, the presence and nature of solvents on the course of this process and the yield of graft copolymers, as well as the study of such important physical and chemical properties and operational properties of the original, irradiated and grafted copolymers, such as sorption capacity and density, hydrophobicity and swelling, degree of whiteness, mechanical properties, thermal stability, the nature of the change in the supramolecular structure as a result of grafting fluorine-containing polymers.

Introduction. A method for protecting concrete and aerated concrete by treatment with a calcium polysulfide-based solution is considered. The solution penetrates into the pores of the materials and, after drying, forms a water-repellent nanoscale layer, protecting the material from water penetration. This ultra-thin layer is formed as a result of the destruction of calcium polysulfide molecules while drying the impregnating solution and gives the material hydrophobic properties. The paper presents research results of the properties and composition of the forming protective layer and its effect on water penetration into the materials. Materials and methods. In the article authors present data on water penetration into the studied concrete and aerated concrete samples, the size and composition of the hydrophobic agent using laser and X-ray diffraction, ultraviolet spectroscopy, as well as using visual research methods, including electron microscopy. Results. It has been revealed that the hydrophobic surface is formed from a mixture of sulfur and calcium carbonate. It is shown that concrete and aerated concrete impregnated with a calcium polysulfide-based solution acquires pronounced water-repellent properties, expressed in contact angles corresponding to superhydrophobic surfaces. The presence of sulfur was established by ultraviolet spectroscopy, and force microscopy showed the formation of nanocomposite particles from sulfur and calcium compounds. X-ray phase analysis showed that the protective layer deposited on the surface of the materials consists of sulfur nanoparticles (65%), as well as nanoparticles of calcium compounds – vaterite (21%) and calcite (13%). Surface treatment of concrete with a sprayer leads to a decrease in water absorption from 5.4% to 3.1%, and in the case of treatment by immersion to a value of 1.5%, while the use of preliminary vacuuming before immersion of the samples allows achieving a water absorption parameter of 0.9%. It is shown that impregnation with preliminary vacuuming leads to water absorption values of less than 1%, which indicates the practical water impermeability of samples of full-scale products (concrete curbs and pipes). Discussion. It is noted that during surface treatment of aerated concrete with a sprayer, a chemically resistant superhydrophobic layer in the form of a nanocomposite is being formed, which penetrates to a depth of 3–3.5 cm, reliably protecting the material from water and chemical penetration. Surface treatment is effective in cases where objects (facades, above-ground structural elements, etc.) are exposed to water in the form of rain. Treatment of concrete products by immersion and immersion treatment with vacuuming can be carried out in harsh cases of constant water exposure (underground utilities, tunnels, manholes). Conclusions. The limitation of water penetration, and in some cases the absence of water in the pores of building materials impregnated with calcium polysulfide, indicate the preservation of substance, since water is a carrier of substances that destroy concrete and aerated concrete. Accordingly, there is no destructive effect from freezing of water in the pores of such materials as a result of the formation of a nano-sized coating of sulfur particles. Comparison of the results for aerated concrete shows that it acquires superhydrophobic properties, which indicates its excellent modification and expands the possibilities of its use. The data observed for concrete products indicate that after treatment with a calcium polysulfide-based solution, they can be used under conditions of long-term and constant exposure to water

Introduction. Impregnation with a solution based on calcium polysulfide showed excellent results in the hydrophobization of concrete, brick and shell rock due to the formation of a water-repellent coating of sulfur nanoparticles on the surface of their pores. This paper presents the data of studying the properties of aerated concrete, widespread in construction practice, which has a widely developed pore system. Materials and methods. The data on the penetration of water into the studied samples of aerated concrete using the methods of visual examination, including electron microscopy, as well as methods for measuring the water absorption and strength of the samples impregnated with a solution based on calcium polysulfide are presented. Results. It is shown that aerated concrete impregnated with calcium polysulfide, despite the developed pore system, acquires pronounced water-repellent properties. It was found that the optimal processing time is 20 minutes, and the increase in the water-repellent properties of aerated concrete depends on the density of the impregnating solution. As a result of impregnation of aerated concrete by immersion in a solution with a density of 1.16 g/cm3, a decrease in 3.7 times occurs, and when treated with a solution with a density of 1.25 g/cm3, it decreases 6.8 times and becomes equal to 6%. For samples processed with the use of vacuum, in the case of processing a solution with a density of 1.16 g/cm3, water absorption decreases by 7.9 times, and when processing with a solution using vacuum, it decreases 19.8 times, while the compressive strength increases by 1.7 once. Samples of aerated concrete, treated with a polysulfide-based solution with a brush, showed that in this case, water absorption in the sprinkling mode decreases to values of 1.5–2.0%. Discussion. It is noted that during the surface treatment of aerated concrete, a chemically resistant, water-repellent layer 3–3.5 cm thick is formed, which reliably protects the material from the penetration of water and chemicals. The results of the performed experiments give reason to believe that on the surface of the pores of aerated concrete treated with a solution based on calcium polysulfide, as well as on the surface of the pores of previously investigated materials, a nanosized coating is formed of sulfur particles that hydrophobic aerated concrete. Conclusions. Comparison of the results for aerated concrete with excellent data for concrete, brick, shell rock shows that the efficiency for aerated concrete is no less and allows us to recommend the specified solution for long-term protection of the surface of aerated concrete walls.

Soil samples and granulodensimetric fractions isolated from them ((silt particle size less than 1 µm, light fraction (LF) with a density of less than 2 g/cm3 and a fraction of the residues) of ordinary chernozem from experimental fields of the Kamennaya Steppe agricultural landscape of the Voronezh region were studied. The main differences between the variants of the experiment are introducing or stopping mineral fertilizers, and in the aftereffect of irrigation (13 years). There is an increase in the content of LF when using mineral fertilizers, as well as a change in the composition of sizedensity fractionations, expressed in different content of C and N and hydrophobic-hydrophilic components of humus substances (HS) of soils, silt and LF. The irrigation had practically no effect on the hydrophobichydrophilic composition of the initial soils, while the relative content of the hydrophilic components of the silt fraction of the soil increased, and the hydrophilic composition of HS LF decreased. The use of mineral fertilizers led to a significant variation in the degree of hydrophilicity of HS in silt and LF with a smaller change of this indicator for the HS of the soil as a whole. The abolition of fertilizers application, on the contrary, affected the hydrophobichydrophilic composition of the soil as a whole, and the composition of the soil silt and LF. The increase in the proportion of hydrophilic components in the composition of soil HS, as well as in the composition of HS silt and LF occurred simultaneously with an increase in the hydrophobicity of the surface of the solid phase of soil and with an increase in the carbon content in the soil, which indicates the stability of the system as a whole. Since the physical fractions of soils reacted more intensively to changes in the agrogenic load, compared with native soil samples, and changes in their qualitative composition were traced in two versions of the experiment, monitoring of hydrophobic-hydrophilic components of soil and soil granulodensimetric fractions is advisable to monitor and diagnose soil changes during agricultural use.

Soil samples and physical size-density fractions isolated from them (silt particle size less than 1 µm, light fraction (LF) with a density of less than 2 g/cm3 and a fraction of the residue) of ordinary chernozem were studied in three contrasting variants of the experimental fields of the Kamennaya Steppe agrolandscape of the Voronezh region: mowed steppe, long-term permanent bare fallow and permanent corn – the main differences of which are in tillage (cultivated and not cultivated lands) and in the supply/absence of plant residues and root secretions. The LF content changes in the series: “mowed steppe” > “permanent corn” > “permanent bare fallow”, which corresponds to the direction of changes in the total carbon content of the soil and a decrease in the value of the contact angle of wetting (CA) of the surface of the solid phase of the studied chernozems. The determination of the total C and N content revealed the change in the qualitative and quantitative composition of the size-density fractions for different land use cases. Chromatographic fractionation of alkaline extractions of humus substances (HS) of chernozem samples and size-density fractions revealed an increase in the degree of hydrophilicity of HS while simultaneously increasing the hydrophobicity of the solid phase surface and the carbon content in the soil. HS of LF of the “mowed steppe” turned out to be by 63% more hydrophilic than HS of LF of “permanent bare fallow” and by 47% more hydrophilic than HS of LF of “permanent corn”. While the hydrophilicity of the HS silt differed by 16 and 27%, respectively. The hydrophilicity of the HS of the original soil in the plot of the “mowed steppe” was by 41% higher than the hydrophilicity of the HS in the soil in the plot of “permanent bare fallow” and by 24% higher than in the soil of the plot of “permanent corn”. In addition, changes in the hydrophilicity of HS of size-density fractions are more intense than the HS of the soil, so the change in the degree of hydrophilicity of HS of size-density fractions is an indicator of soil degradation under different agrogenic pressue.

Introduction. The present study assessed Pseudomonas aeruginosa surface characteristics, motility and adhesion properties under the influence of 1-[4-(1,1,3,3-tetra methyl butyl) phenoxy]-3-(N-benzyl hexa methylene iminium)-2-propanol chloride (KVM-194). Material and methods. The clinical strain P. aeruginosa 449 was used in the study. The cell surface hydrophobicity (CSH) was evaluated by adhesion to solvent (MATS test). Swimming, swarming and twitching motility of P. aeruginosa were studied by standard methods in media with different agar contents. Cells ability to adhere to polystyrene was assessed by the Christensen method. The effect of KVM-194, meropenem and ciprofloxacin on hydrophobicity and motility was evaluated both at 0.5 or 2.0 minimal inhibitory concentrations (MIC), while on adhesion abilities – only 0.5×MIC. Results. It was shown that 0.5× MIC KVM-194 reduced CSH of P. aeruginosa (by 16%, p˂0.05), affected swimming motility, and decreased its adhesion to polystyrene. The most pronounced changes in adhesion properties were recorded after 3-5 hours of pre-treatment with this compound. Moreover, it was proven that sub-MICs of meropenem and ciprofloxacin did not alter bacterial cells hydrophobicity and had no significant influence on P. aeruginosa motility and adhesion properties. Conclusions. The present study suggested that KVM-194 affected the initial steps of P. aeruginosa biofilm formation and thus had tremendous potential for new antibiofilm agents’ development.

Natural glauconite-based sorbents were obtained for skimming oil and oil products from different surfaces. Glauconite is an aluminosilicate mineral and is widely used for cleaning various pollutants from water and soil. The classifi cation allowed selecting a glauconite fraction with a particle size of 0.045-0.1 mm, which is the most effective for the sorption of oil products. For this, the sorbent was thermally activated and modifi ed using organic compounds. The glauconite samples were thermally treated at temperatures of 100, 600, and 1000 °C. To provide glauconite with hydrophobic properties, it was modifi ed with stearic acid. When the sorbents came into contact with water (duration 92 hours), it was found that with the mass fraction of stearic acid of 5 wt% the lowest weight loss was observed in all the three samples. The contact angle of wetting for sorbents is greater than 90°, which led to a change in the state of its surface. The obtained samples were not wetted with water and could remain on its surface for a long time. The interaction of oil and a hydrophobic sorbent showed that after seven minutes the particles of the sorbent penetrated the oil that also has a hydrophobic surface and can sorb a surfactant applied on the sorbent, which indicates the affi nity of stearic acid to oil. A granular sorbent, thermally activated at a temperature of 1000°C and modifi ed with a cellulose-containing component, sorbed the oil for 2 minutes. The use of this modifi er increased the sorbent porosity, which affected the sorption rate.

The parameters of hydrophobicity of five oligomycins, i. e. A, B, C, F and SC-II were determined by HPLC. The location of the ascending hydrophobicity parameter was set: oligomycin B < oligomycin SC-II < oligomycin A < oligomycin F < oligomycin C.

The sessile drop method was used to measure the contact angle of wetting (CA) of ordinary Chernozem from the fields of the Kamennaya Steppe agrolandscape used in various ways. The treatments differ in the intensity of tillage operations (protected mowed steppe, arable land after moldboard plowing), the use of mineral fertilizers and their aftereffect, as well as changes in soil properties under the influence of irrigation. At the same time, the total organic carbon content, C/N ratio, specific surface area, and rheological parameters were determined for the physical and chemical characteristics of soils. The results of the study showed that the hydrophilic-hydrophobic properties of the surface of the solid phase of soils, which largely determine the main structure-forming properties of soils, can be characterized by the value of the wetting edge angle. The CA of the studied soil samples varies from 32 degrees (highest wettability) to 45 degrees (lowest wettability). The lowest wettability is due to the increased content of hydrophobic compounds in the organic matter of soils and is characterized by the highest CA and is typical for native, untreated soil of the mowed steppe, which differs from other studied variants of the experiment in all explored physical and chemical parameters. Moldboard plowing as well as fallowing lead to changes in the physical and chemical properties of the soil and the qualitative composition of organic matter in the direction of their deterioration and a decrease in the CA. The use of mineral fertilizers contributes to the increase in the studied indicator mainly due to changes in plant productivity, in particular, the differences in CA are due to the impact of root secretions and plant residues on the soil properties. For the studied soils, the CA changes in the following series: mowed steppe > arable land with the mineral fertilizers application > arable land undergone the aftereffect of fertilizers. Correlation analysis revealed the relationship of CA with organic carbon content, specific surface area, and rheological characteristics of Chernozems. Thus, CA can serve as an integral indicator of changes in the physical and chemical properties of soils, their degradation changes under the conditions of different agricultural load. The method used in this research for determining CA requires a smaller amount of sample compared to rheological methods and is generally more informative than determining the content of organic matter.

Stabilisation of the functional properties of dispersed and compact metals, as well as the regulation of their reactivity, improvement of water-repellent, antifriction and anti-corrosion properties by creating the protective films on the surface is an urgent problem in relation to obtaining new materials. Previously, research conducted at REC “Nanotechnology” of the St. Petersburg Mining University proved that chemisorption of ethylhydridesiloxane vapours together with surfactants based on quaternary ammonium compounds has a beneficial effect on the water-repellent properties of metals. In order to obtain the physicochemical mechanism of the hydrophobisation of the surface of modified dispersed metals for the first time, the study of the electrophilic-nucleophilic properties of the active substances of the surface modifiers of metals was carried out using the methods of quantum-chemical modelling using HyperChem software package. The dipole moment, energy of the highest occupied and the lowest unoccupied molecular orbitals, electrophilic-nucleophilic properties were determined. The series of enhancement of ucleophilic/electrophilic properties and dipole moment for modifiers were obtained. The donor-acceptor properties, the differences in the characteristics of the molecules of alkamon, triamon, and hydrophobic silicone organic liquid were quantitatively and qualitatively established. The regularities of the formation of hydrophobic and antifriction properties in the composition of industrial oil I-20-surface-modified metal with various electrophilic-nucleophilic properties of the applied substances

The method of soil samples preparation for measuring the (wetting) contact angle (CA) of the soil solid phase surface using membrane filters is proposed. The samples of kaolinite, a standard sample of chernozem and samples of agro-chestnut soil were taken for the experiment. The results of the CA measurements using two types of sample preparation for the analysis were compared. The first method of sample preparation was to apply a sample to a double-sided adhesive tape; the second method involved the deposition of suspensions of the studied samples of certain concentrations on membrane filters. The advantages and disadvantages of each sample preparation method are described. The significant difference in the obtained CA values depending on the sample preparation for measurement was revealed. The method of sample preparation with the use of membrane filters developed by the authors made it possible to reduce the CA measurement error by more than 2 times. Reducing the variation of the CA value of a single sample will allow comparing similar soil samples, including soils of the same type, but involved in different land use systems.

Purpose. The change in sorption properties of stabilized dispersed copper with layered ammonium compounds resulting from long-term (up to 200 hours) interaction with saturated water vapours was studied. Methods and methodology. The stabilized copper powder, PMS-1, with an average particle size of about 84 microns and a moisture content of less than 0.05 %, was used as the initial dispersed metal. Particle size measurements and the calculation of the specifi c surface area of the samples were performed using laser diffraction data (Malvern Mastersizer 3000). Modifi cation of the surface of copper powders was carried out in a gas environment by vapours of alkamon and/or triamon based on quaternary ammonium compounds and by vapours of hydrophobic silicon-organic liquid HSL based on ethylhydridesiloxane. The composition of triamon in vapours corresponds to the chemical formula with low molecular (C1–C2) organic radicals in the nitrogen atom. The cationic part of alkamon contains a larger hydrocarbon radical – C17. The following copper-based samples were obtained by means of consecutive and mixed treatment with the vapours of the above mentioned reagents: Cu/(A+T), Cu/A, Cu/T, Cu/T/A, Cu/A/T, Cu/A/HSL, Cu/T/HSL. The water vapour sorption and adsorption isotherms of the samples were measured gravimetrically, using the exicator method, with a vapor pressure of PH2O/PS ranging from 0.45 to 1.00 (where Ps is the saturation pressure). The adsorption of water vapour was additionally evaluated by the presence of the O1s peak with the binding energy of 532.5 eV (VG Escalab 220iXL). Results. The analysis of adsorption isotherms of surface-modifi ed copper samples shows a weak adsorbate-adsorbent interaction. The isotherms are most typical for non-porous solids. The highest level of water adsorption within the fi rst 100 hours of interaction (PH2O/Ps = 0.98±0.02) was demonstrated by the initial copper powder (PMS-1). The sorption level for the Cu/A/HSL sample is more than twice lower. Samples Cu/HSL and Cu/(A+T) have the lowest level of water vapour adsorption. Within the time interval from 130 to 216 hours it remains constant (0.0063 and 0.0049 g/g, respectively). The obtained results are important for the creation of chemically stable and waterrepellent metallic fi llers and additives, as well as components of materials used in electronics. Conclusion. It was determined that during long-term (24–216 hours) interactions of saturated water vapour with surface-modifi ed copper-based powders, the magnitude of water sorption (a, g/g) changes according to a complex function, similar to the one describing damped oscillations. A mathematical description of the process based on the linear and the Gauss function was proposed. It allows to approximate the experimental data (relative error 5–7 %) of the time dependences a = f(t) and 1/a = F(t). The suggested description is relatively simple, physically meaningful and allows for quantitative description of nonlinear effects in the studied systems. It was shown that among the synthesized copper-based samples with adsorbed reagents based on quaternary ammonium compounds (triamon-T and alkamon-A) and organohydridesiloxane adsorbed from the vapours of HSL, the most hydrophobic are samples of Cu/A/HSL and Cu/T/A with consequently applied layers of structurally similar substances, such as ammonium compounds with molecules of different size (Cu/T/A).

The paper is devoted to the development of a mathematical model for high-pressure hydro vortex inertial kinematic dust suppression. The suppression can significantly improve the efficiency of localization of man-made accidents and reduce the level of occupational pulmonary diseases. The dynamics of improving the technology and technical means of dust suppression in the mining and metallurgical complex of Russia shows their lack of effectiveness in ensuring sanitary conditions, especially in localization of dust mixture explosions. A further increase in the efficiency of coal mining and mineral processing is significantly limited by the imperfection of the technology for localizing and eliminating explosions of coal dust. The method of high-pressure hydro vortex dedusting is developed based on the theory of attached vortices. A mathematical model of hydro vortex inertial, kinematic heterocoagulation, which significantly increases the energy efficiency of dust suppression, is proposed. The graphical model of the interaction in the contact zone at the time of the collision in the liquid-solid system is refined. Stokes and Reynolds criteria equations are obtained with hydro vortex inertial orthokinetic heterocoagulation. An equation is obtained which allows to calculate the magnitude of the reduction in the required energy of the total absorption of dust particles as a function of the circulation of liquid droplets. Equations for calculation of effective wetting angle and the minimum diameter of absorbed dust particles are obtained as a function of the angular velocity of rotation of liquid droplets. It is shown that hydro vortex coagulation significantly reduces the size of the dispersed dust composition, water consumption, increasing the efficiency of dust suppression. A significant decrease in the size of the absorbed dust particles increases the efficiency of localization of coal dust explosions, reduces the incidence of silicosis and anthracosis. Certification tests using patent-protected vortex nozzles confirmed that there was a reduction in the minimum size of absorbed dust in four times, increase in dust collection efficiency of up to 99 %, reduce in water consumption by 20 % compared to classic high-pressure spray cleaning. The proposed technology of dust suppression can be used in mining companies when fine explosive dust mixtures are formed.

Polymeric materials are characterized by low values of the surface energy; they are poorly wetted by solvents, and have low adhesion to different materials and other disadvantages. The relevance of the work stems from the need to develop specific surface properties of the polymer prostheses used in cardiovascular surgery, to increase the biocompatibility and hemocompatibility. One of the most promising and modern methods of surface modification of polymers is the impact of low-temperature plasma. Modern plasma-chemical methods have some advantages in comparison with chemical modification, where aggressive reagents and their compounds are used. The main aim of the research is to change surface properties of polymer materials for cardiovascular surgery by the plasma chemical modification methods. The research methods: The authors have applied the modern technology of polymer compositions manufacture. This is electrospinning method, which allows obtaining porous structures, adding cells and active substances. The authors selected environmentally and chemically safe impact method to the surface of the obtained products. This is plasma chemical modification, which doesn't influence the physical properties of the final product. Modification was carried out on the electrode system with preionizers, which was developed by the laboratory № 1 of the Institute of Physics High Technologies at Tomsk Polytechnic University (head of the development is Remnev G.E.). The results: The authors proposed the method of handling the surface properties of polymer products, which are responsible for wettability and surface free energy. It was shown that plasma-chemical methods of gas discharge influence on polymeric material surface allow regulating their contact properties. The main changes in wettability degree occur within a short exposure time of pulsed plasma at atmospheric pressure on polymeric material surface (from one to sixty seconds). The values of wettability contact angle for the modified polymers depend on gaseous medium nature and handling conditions in plasma. Changing pulse power and repetition rate and the processing time it is possible to control surface free energy, which allows adjusting wettability, making the surface more hydrophobic or hydrophilic.

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The research on the problems of normative support for quality control of silica filler with a reduced tendency to aggregation, obtained from hybrid gels of the system MTEOS-TEOS-water-alcohol under conditions of variable pH was given. As a result of the conducted studies, the technology for hybrid filler with a homogeneous structure and uniform particles surface hydrophobization was developed. It was established that the inincrease in the ratio MTEOS/TEOS in the gel increases the particles adsorption activity of the silica powder and its hydrophobicity degree due to the methyl groups presence on the particles surface. It was found that the alkali concentration at TEOS and MTEOS hydrolysis products joint coagulation has a decisive influence on the homogeneity degree of powder and its physicochemical characteristics. The method of quality control of the hybrid silica filler of dental composite materials was developed. [ABSTRACT FROM AUTHOR]

Plants possess several neurotransmitters with well-known physiological roles. Currently only receptors for glutamate were reported to be found in plants, while receptors for acetylcholine, serotonin and GABA have not yet been reported. In animals, these neurotransmitters act via one class of ligand binding ion channels called Cys-loop receptors which play a major role in fast synaptic transmission. They show the presence of two domains namely Neurotransmitter-gated ion-channel ligand-binding domain (Pfam: PF02931) and Neurotransmitter-gated transmembrane domain (Pfam: PF02932). Cys-loop receptors are also known in prokaryotes. No cys-loop receptor has been characterized from plants yet. In this study, the Ensembl plants database was searched for proteins with these two domains in the sequenced plant genomes, what resulted in only one protein (LIC1) from the alga Chlamydomonas reinhardtii. BLAST and profile HMM searches against the pdb structure database showed that this protein is related to animal and prokaryotic cys-loop receptors, although the cysteine residues characteristic of the cys-loop are absent. Physico-chemical and sequence analysis indicate that LIC1 is an anionic receptor. A model of this protein was generated using homology modeling based on a nicotinic acetylcholine receptor of Torpedo marmorata. The characteristic extracellular domain (ECD) and transmembrane domain (TMD) are well structured but the intercellular region is poorly formed. This is the first report on a detailed characterization of a cys-loop receptor from the plant kingdom.