The synthesis and spectral characterization of the 5-(2,6-dichlorobenzylidene)pyrimidine-2,4,6(1H,3H,5H)-trione;3 was reported. The solid state molecular structure of 3 was studied using X-ray crystallography. The relative stabilities of the seven possible isomers of 3 were calculated by DFT/B3LYP method using 6-311 G(d,p) basis set. The calculated total energies and thermodynamic parameters were used to predict the relative stabilities of these isomers. The effect of solvent polarity on the relative stability of these isomers was studied at the same level of theory using PCM. It was found that the keto form, (T0), is the most stable isomer both in the gaseous state and solution. In solution, the calculated total energies of all isomers are decreased indicating that all isomers are stabilized by the solvent effect. The vibrational spectra of the most stable isomer, 3(T0) are calculated using the same level of theory and the results are compared with the experimentally measured FTIR spectra. Good correlation was obtained between the experimental and calculated vibrational frequencies (R(2)=0.9992). The electronic spectra of 3(T0) in gas phase as well as in solutions were calculated using the TD-DFT method. All the predicted electronic transitions showed very little spectral shifts and increase in the intensity of absorption due to solvent effect. Also the (1)H- and (13)C-NMR chemical shifts of the stable isomer were calculated and the results were correlated with the experimental data. Good correlations between the experimental and calculated chemical shifts were obtained.
In this study, oil palm mesocarp fiber (OPMF) was treated with superheated steam (SHS) in order to modify its characteristics for biocomposite applications. Treatment was conducted at temperatures 190-230 °C for 1, 2 and 3 h. SHS-treated OPMF was evaluated for its chemical composition, thermal stability, morphology and crystallinity. OPMF treated at 230 °C exhibited lower hemicellulose content (9%) compared to the untreated OPMF (33%). Improved thermal stability of OPMF was found after the SHS treatment. Moreover, SEM and ICP analyses of SHS-treated OPMF showed that silica bodies were removed from OPMF after the SHS treatment. XRD results exhibited that OPMF crystallinity increased after SHS treatment, indicating tougher fiber properties. Hemicellulose removal makes the fiber surface more hydrophobic, whereby silica removal increases the surface roughness of the fiber. Overall, the results obtained herewith suggested that SHS is an effective treatment method for surface modification and subsequently improving the characteristics of the natural fiber. Most importantly, the use of novel, eco-friendly SHS may contribute to the green and sustainable treatment for surface modification of natural fiber.
In this study, dye-sensitized solar cells (DSSCs) has been assembled with poly(1-vinylpyrrolidone-co-vinyl acetate) (P(VP-co-VAc)) gel polymer electrolytes (GPEs) which have been incorporated with binary salt and an ionic liquid. The potential of this combination was studied and reported. The binary salt system GPEs was having ionic conductivity and power conversion efficiency (PCE) that could reach up to 1.90 × 10(-3) S cm(-1) and 5.53%, respectively. Interestingly, upon the addition of the ionic liquid, MPII into the binary salt system the ionic conductivity and PCE had risen steadily up to 4.09 × 10(-3) S cm(-1) and 5.94%, respectively. In order to know more about this phenomenon, the electrochemical impedance studies (EIS) of the GPE samples have been done and reported. Fourier transform infrared studies (FTIR) and thermogravimetric analysis (TGA) have also been studied to understand more on the structural and thermal properties of the GPEs. The Nyquist plot and Bodes plot studies have been done in order to understand the electrochemical properties of the GPE based DSSCs and Tafel polarization studies were done to determine the electrocatalytic activity of the GPE samples.
The aim of this work is to study the behavior of biodegradable sugar palm starch (SPS) based thermoplastic containing agar in the range of 10-40wt%. The thermoplastics were melt-mixed and then hot pressed at 140°C for 10min. SEM investigation showed good miscibility between SPS and agar. FT-IR analysis confirmed that SPS and agar were compatible and inter-molecular hydrogen bonds existed between them. Incorporation of agar increased the thermoplastic starch tensile properties (Young's modulus and tensile strength). The thermal stability and moisture uptake increased with increasing agar content. The present work shows that starch-based thermoplastics with 30wt% agar content have the highest tensile strength. Higher content of agar (40wt%) resulted to more rough cleavage fracture and slight decrease in the tensile strength. In conclusion, the addition of agar improved the thermal and tensile properties of thermoplastic SPS which widened the potential application of this eco-friendly material. The most promising applications for this eco-friendly material are short-life products such as packaging, container, tray, etc.
The photostabilization of polyvinyl chloride (PVC) films by Schiff bases was investigated. Polyvinyl chloride films containing 0.5 wt % Schiff bases were produced using the same casting method as that used for additive-free PVC films from tetrahydrofuran (THF) solvent. The photostabilization activities of these compounds were determined by monitoring the carbonyl, polyene and hydroxyl indices with irradiation time. The changes in viscosity average molecular weight of PVC with irradiation time were also monitored using THF as a solvent. The quantum yield of chain scission (Φcs) for the studied complexes in PVC was estimated to range between 4.72 and 8.99 × 10(-8). According to the experimental results, several mechanisms were suggested, depending on the structure of the additive. Ultra violet (UV) absorption, peroxide decomposition and radical scavenging were suggested as the photostabilizing mechanisms.
We demonstrate a green chemistry approach to synthesize narrow-sized zerovalent iron (nZVI) nanoparticles using Artocarpus heterophyllus Lam. leaf extract as reducing and capping agent. The produced nZVI was characterized by various instrumental methods including ultraviolet-visible spectra, transmission electron microscopy, vibrating sample magnetometer (VSM), X-ray diffraction, and Fourier transform infrared spectroscopy. Based on the electron microscopy observations, the particle size was estimated to be ∼30 nm. In VSM, the saturation point of magnetization was observed to be 0.6 emu g-1 under a magnetic field of 0 ± 30 kOe. The synthesized nZVI was amorphous in nature as per the XRD results. The catalytic activity of the nZVI was employed for the catalytic reduction of 4-nitrophenol (4-NP) and decoloration of textile dyes such as methylene blue, methyl orange, and malachite green, respectively. The proposed nZVI synthesis method exhibited better catalytic performance toward reduction of 4-NP and degradation of dyes within 4 min for 0.1 mg of catalyst. Moreover, the synthesized catalyst nZVI can be recoverable and reutilized in many cycles without loss of its significant catalytic activity. The synthesized nZVI could be a promising material to treat industrial wastewater via profitable, sustainable, and ecofriendly approaches.
Frequent droughts significantly affect agricultural productivity and highlight the need for effective solutions to improve water availability for crops. This study investigates the potential of chitosan-based hydrogels, biodegradable biopolymers known for their water-retaining properties, to improve soil moisture and promote plant growth during drought periods. Chitosan hydrogels were synthesized using Pluronic F127 and compared with chitosan and chitosan in combination with sodium alginate (CS/Alg-Na). Comprehensive chemical characterizations were performed by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) and field emission scanning electron microscopy (FESEM). The CS/Pl-F127 hydrogels showed high porosity and a water absorption capacity of 81.5 %, while the CS/Alg-Na exhibited a denser network with a capacity of 93.35 % and improved mechanical strength. Plants in the CS/Pl-F127 hydrogel had a shoot elongation rate of 5.9 mm/day on Day 9, which continued until Day 40. In contrast, shoot elongation in the CS/Alg-Na hydrogel peaked at 7.1 mm/day on Day 20 and maintained growth under drought conditions until Day 33. These results show that all chitosan-based hydrogels improve water use efficiency. CS/Alg-Na provides the best support for plant growth under drought conditions, followed by CS/Pl-F127 and pure chitosan.
Mushrooms are considered one of the safe and effective medications because they have great economic importance due to countless biological properties. Cordyceps militaris contains bioactive compounds with antioxidant, antimicrobial and anti-cancerous properties. This study was projected to analyze the potentials of biometabolites and to extract antimicrobial peptides and protein from the C. militaris. An in-vitro analysis of biometabolites and antimicrobial peptides was performed to investigate their pharmacological potentials followed by quantification and characterization of extracted protein. Computational analysis on non-small cell lung cancer genes (NSCLC) was performed on quantified compounds to interpret the biometabolites from C. militaris that could be potential drug candidate molecules with high specificity and potency. A total of 34 compounds representing 100% of total detected constituents identified were identified using GCMS analysis and 20 compounds using LC-MS which showed strong biological activities. FT-IR spectroscopy manifest powerful instant peaks to have different bioactive components including carboxylic acid, phenols, amines and alkanes present in methanolic extract of C. militaris. In C. militaris, higher protein concentration was observed in 70% concentration of protein extract (500 μg/ml ± 0.025). The best antioxidant activity (% Radical scavenging activity) of methanolic extracts was 80a ± 0.03, antidiabetic activity was 37 ± 0.057 and anti-inflammatory activity was 40 ± 0.021 at 12 mg/ml. Antibacterial activity for different concentrations of Cordyceps protein and methanolic extracts was significantly (p < 0.05). Indolizine, 2-(4-methylphenyl) has most binding affinity (micromolar) and optimized properties to be selected as the lead inhibitor. It interacts favorably with the active site of RET gene of NSCLC and is neuroprotective and hepatoprotective.
The research aimed to develop improved bioadhesives from cassava starch by utilizing a specialized NaOH-urea solution to address issues with conventional starch adhesives, including excessive thickness, low solid content, weak bonding strength, and instability due to retrogradation. Cassava starch was extracted through wet milling and incorporated into the adhesive formulation at 1-9 %. The method produced starch granules that are less damaged, with decreased peak viscosity and swelling properties. The bio-adhesives were created using a cold gelatinization process. The process requires less energy, preventing thermal degradation, controlling viscosity, and reducing retrogradation. The properties of the starch were studied using various techniques, including thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), and differential scanning calorimetry (DSC), as well as tests for swelling and solubility. The findings indicated that the extracted starch had a moisture level of 8.00 %, a pH of 5.97, and comprised 24.95 % amylose and 75.05 % amylopectin. Increasing the starch content enhances the viscosity (1110 cP), solid content (14 %), and tensile strength (both in wet and dry conditions), as well as the adhesive's internal bonding, while also decreasing the gel time (271 s), making it more suitable for wood-based composites. XRD and FTIR analyses validated the morphological alterations caused by the NaOH-urea treatment. The starch-based adhesive (9 % SBA) exhibited superior performance. This study demonstrated the first systematic implementation of the cold gelatinization process, specifically applied to cassava starch for use in wood adhesives.
In this study, environmental stability, rheological properties, and structural characterization of co-stabilized emulsions using fish gelatin (FG) and tea saponin (TS) were investigated. The results demonstrated that the addition of TS significantly enhanced the emulsifying properties of FG, and the FG-TS0.1% emulsion had the smallest particle size. TS and FG co-stabilized emulsions provided resistance to salt and high temperatures. Optical microscopy and CLSM showed that the addition of TS made FG more effectively adsorb at the oil-water interface, leading to the formation of more uniform oil droplet sizes. Additionally, the addition of TS increased the viscosity of FG emulsions, which reduced emulsion flocculation. Results of intrinsic fluorescence, FTIR, and surface hydrophobicity revealed that the addition of TS altered the secondary structure of FG, enhancing surface hydrophobicity and improving emulsification. In conclusion, the moderate addition of TS significantly enhanced the emulsification and rheological properties of FG, suggesting new potential applications for FG in various industries.
Synergistic reduction of graphene oxide (GO) using different reducing agents represents an effective approach for reduced graphene oxide (rGO) synthesis. In this study, the rGO (rGO-Vc+Urea) was prepared by combining vitamin C (Vc) and urea as co-reducing agents with the modified Hummer's method. Compared to samples reduced solely with Vc or urea, the co-reducing agents significantly reduced the required reaction time (to 2 hours) and temperature (to 120°C), while yielding material with superior electrical resistivity (1.2 Ω·cm). The structure of the samples was characterized using XRD, FT-IR, Raman spectroscopy, BET surface area analysis, and SEM. Results indicate that the sample prepared from co-reducing agents possesses a typical graphene structure and incorporates C-N bonds. Furthermore, rGO-Vc+Urea exhibits a higher degree of structural order, as evidenced by a lower Raman (Iᴅ/IG = 0.75), compared to rGO-Vc (Iᴅ/IG = 0.91) and rGO-Urea (Iᴅ/IG = 1.49), along with a higher specific surface area (88.60 m2/g). The reduction mechanism of the co-reducing agents was investigated. It was revealed that the alkaline environment generated by urea enhances Vc's ability to reduce oxygen-containing functional groups in GO, specifically hydroxyl, epoxy, carbonyl, and carboxyl groups, and promotes the elimination of CO2 released during the reaction. This strategy of employing synergistic multiple reducing agents offers new perspectives for the preparation of rGO.
Water bodies with the dye methylene blue pose serious environmental and health risks to humans. Therefore, the creation and investigation of affordable, potential adsorbents to remove methylene blue dye from water resources as a long-term fix is one focus of the scientific community. Food plants and other carbon-source serve as a hotspot for a wider range of application on different pollutants that impact the environment and living organisms. Here, we reviewed the use of treated and untreated biosorbents made from plant waste leaves for removing the dye methylene blue from aqueous media. After being modified, activated carbon made from various plant leaves improves adsorption performance. The range of activating chemicals, activation methods, and bio-sorbent material characterisation using FTIR analysis, Barunauer-Emmett-Teller (BET) surface area, scanning electron microscope (SEM-EDX), and SEM-EDX have all been covered in this review. It has been thoroughly described how the pH solution of the methylene blue dye compares to the pHPZC of the adsorbent surface. The presentation also includes a thorough analysis of the application of the isotherm model, kinetic model, and thermodynamic parameters. The selectivity of the adsorbent is the main focus of the adsorption kinetics and isotherm models. It has been studied how adsorption occurs, how surface area and pH affect it, and how biomass waste compares to other adsorbents. The use of biomass waste as adsorbents is both environmentally and economically advantageous, and it has been discovered to have exceptional color removal capabilities.
Ex-mining lake-converted constructed wetlands play a significant role in the carbon cycle, offering a great potential to sequester carbon and mitigate climate change and global warming. Investigating the quantity of carbon storage capacity of ex-mining lake-converted constructed wetlands provides information and justification for restoration and conservation efforts. The present study aims to quantify the carbon pool of the ex-mining lake-converted constructed wetlands and characterise the physicochemical properties of the soil and sediment. Pearson's correlation and a one-way ANOVA were performed to compare the different sampling stations at Paya Indah Wetland, Selangor, Malaysia. An analysis of 23 years of ex-mining lake-converted constructed wetlands of Paya Indah Wetlands, Selangor, Malaysia, revealed that the estimated total carbon pool in soil and sediment accumulated to 1553.11 Mg C ha-1 (equivalent to 5700 Mg CO2 ha-1), which translates to an annual carbon sink capacity of around 67.5 Mg C ha-1 year-1. The characterisation showed that the texture of all soil samples was dominated by silt, whereas sediments exhibited texture heterogeneity. Although the pH of the soil and sediment was both acidic, the bulk density was still optimal for plant growth and did not affect root growth. FT-IR and WDXRF results supported that besides the accumulation and degradation of organic substances, which increase the soil and sediment carbon content, mineral carbonation is a mechanism by which soil and sediment can store carbon. Therefore, this study indicates that the ex-mining lake-converted constructed wetlands of Paya Indah Wetlands, Selangor, Malaysia have a significant carbon storage potential.
This study highlights the biosorption capacity for Cd (II), Cu (II) and Pb (II) by a locally isolated Pseudomonas aeruginosa DR7. At initial concentrations of 150 mg L-1 and 240 min of contact time, P. aeruginosa DR7 showed a 62.56 mg/g removal capacity for Cd (II) at an optimum pH of 6.0, 72.49 mg/g for Cu (II) at an optimum pH of 6.0, and 94.2 mg/g for Pb (II) at an optimum pH of 7.0. The experimental data of Cd (II), Cu (II), and Pb (II) adsorbed by the pseudo-second-order kinetic model correlates well with P. aeruginosa DR7, with R2 all above 0.99, showing that the fitting effect was satisfactory. The isothermal adsorption processes of Cd (II) (0.980) and Cu (II) (0.986) were more consistent with the Freundlich model, whereas Pb (II) was more consistent with the Langmuir model (0.978). FTIR analysis suggested the involvement of hydroxyl, carbonyl, carboxyl, and amine groups present in the inner regions of P. aeruginosa cells during the biosorption process. SEM-EDS analysis revealed that after contact with metals, there were slight changes in the surface appearance of the cells, which confirmed the deposition of metals on the bacterial surface. There was also the possibility of the metals being translocated into the bacterial inner regions by the appearance of electron-dense particles, as observed using TEM. As a conclusion, the removal of metals from solutions using P. aeruginosa DR7 was a plausible alternative as a safe, cheap, and easily used biosorbent.
The synergistic effects of antimicrobial nanostructures with antibiotics present a promising solution for overcoming resistance in methicillin-resistant Staphylococcus aureus (MRSA). Previous studies have introduced iron as a novel coating for silver nanoparticles (AgNPs) to enhance both economic efficiency and potency against S. aureus. However, there are currently no available data on the potential of these novel nanostructures to reverse MRSA resistance. To address this gap, a population study was conducted within the MRSA community, collecting a total of 48 S. aureus isolates from skin lesions. Among these, 21 isolates (43.75%) exhibited cefoxitin resistance as determined by agar disk diffusion assay. Subsequently, a PCR test confirmed the presence of the mecA gene in 20 isolates, verifying them as MRSA. These results highlight the cefoxitin disk diffusion susceptibility test as an accurate screening method for predicting mecA-mediated resistance in MRSA. Synergy tests were performed on cefoxitin, serving as a marker antibiotic, and iron-coated AgNPs (Fe@AgNPs) in a combination study using the checkerboard assay. The average minimal inhibitory concentration (MIC) and fractional inhibitory concentration (FIC) of cefoxitin were calculated as 11.55 mg/mL and 3.61 mg/mL, respectively. The findings indicated a synergistic effect (FIC index
Molten salts are the operational fluid for most concentrated solar power (CSP) systems, which has attracted more attention among the scientific community due to the augmentation of their properties with the doping of nanoparticles. Hexagonal boron nitride (h-BN) nanoparticles were dispersed in HITEC molten salt to create a novel nanofluid and evaluate the h-BN nanoparticles' influence on HITEC thermophysical properties. The influence of nanoparticle concentration (0.1, 0.5, and 1wt.%) of h-BN and HITEC was studied in this research. HITEC and nano-enhanced HITEC molten salt (NEHMS) were characterized using energy-dispersive X-ray spectroscopy (EDX), field emission scanning electron microscopy (FESEM), and Fourier transform infrared spectroscopy (FT-IR). Specific heat capacity, latent heat, and melting temperature were assessed using differential scanning calorimetry (DSC). The maximum working temperature was evaluated with thermogravimetric analysis (TGA). The ideal nanoparticle concentration is 0.1 wt.% h-BN, which results in a 27% increase in heat capacity, a 72% increase in latent heat, and a 7% enhancement in thermal stability. The thermal cycling stability test proved the stability of the enhanced thermophysical properties. The material characterization revealed that the samples with improved thermophysical properties have a homogeneous dispersion of nanoparticles with minor nanoparticle agglomeration. The system advisor model (SAM) simulation comparison of the optimum sample with solar salt and HITEC salt revealed that using the optimum sample increases CSP plant efficiency by 0.4% and reduces power costs by 0.13¢/kWh.
Copolymerization is a cooperative polymerization that involves two or more different monomers that are incorporated into the same polymer chain. It allows the development of unlimited range of polymers, tunable properties and surface modifications. In this study, the oil-free base treated soybean waste was used as a biomass precursor and it was copolymerized with acrylamide through the free radical polymerization with potassium persulfate as initiator. The adsorption characteristic of the newly prepared acrylamide-soybean copolymer towards Pb(II) was studied by the use of Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and thermogravimetric analysis (TGA). The adsorption conditions were optimized in terms of pH, adsorbent dosage and contact time. The Freundlich isotherm model can fit well the adsorption data obtained towards Pb(II). In comparison, the pseudo-second-order is the better fit kinetic system that explained the adsorption mechanism of Pb(II) onto the acrylamide-soybean copolymer. The adsorption capacity of the acrylamide-soybean copolymer was determined to be 22.12 mg g-1, which is comparable with the absorption capacity of other grafted polymers.
Protein drugs may encounter conformational perturbations during the formulation processing of lipid-based solid dosage forms. In aqueous protein solutions, attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy can investigate these conformational changes following the subtraction of spectral interference of solvent with protein amide I bands. However, in solid dosage forms, the possible spectral contribution of lipid carriers to protein amide I band may be an obstacle to determine conformational alterations. The objective of this study was to develop an ATR FT-IR spectroscopic method for the analysis of protein secondary structure embedded in solid lipid matrices. Bovine serum albumin (BSA) was chosen as a model protein, while Precirol AT05 (glycerol palmitostearate, melting point 58 ℃) was employed as the model lipid matrix. Bovine serum albumin was incorporated into lipid using physical mixing, melting and mixing, or wet granulation mixing methods. Attenuated total reflection FT-IR spectroscopy and size exclusion chromatography (SEC) were performed for the analysis of BSA secondary structure and its dissolution in aqueous media, respectively. The results showed significant interference of Precirol ATO5 with BSA amide I band which was subtracted up to 90% w/w lipid content to analyze BSA secondary structure. In addition, ATR FT-IR spectroscopy also detected thermally denatured BSA solid alone and in the presence of lipid matrix indicating its suitability for the detection of denatured protein solids in lipid matrices. Despite being in the solid state, conformational changes occurred to BSA upon incorporation into solid lipid matrices. However, the extent of these conformational alterations was found to be dependent on the mixing method employed as indicated by area overlap calculations. For instance, the melting and mixing method imparted negligible effect on BSA secondary structure, whereas the wet granulation mixing method promoted more changes. Size exclusion chromatography analysis depicted the complete dissolution of BSA in the aqueous media employed in the wet granulation method. In conclusion, an ATR FT-IR spectroscopic method was successfully developed to investigate BSA secondary structure in solid lipid matrices following the subtraction of lipid spectral interference. The ATR FT-IR spectroscopy could further be applied to investigate the secondary structure perturbations of therapeutic proteins during their formulation development.
The study aims to characterize the structural relaxation times of quench-cooled co-amorphous systems using Kohlrausch-Williams-Watts (KWW) and to correlate the relaxation data with the onset of crystallization. Comparison was also made between the relaxation times obtained by KWW and the width of glass transition temperature (ΔTg) methods (simple and quick). Differential scanning calorimetry, Fourier-transformed infrared spectroscopy, and polarized light microscopy were used to characterize the systems. Results showed that co-amorphous systems yielded a single Tg and ΔCp, suggesting the binary mixtures exist as a single amorphous phase. A narrow step change at Tg indicates the systems were fragile glasses. In co-amorphous nap-indo and para-indo, experimental Tgs were in good agreement with the predicted Tg. However, the Tg of co-amorphous nap-cim and indo-cim were 20°C higher than the predicted Tg, possibly due to stronger molecular interactions. Structural relaxation times below the experimental Tg were successfully characterized using the KWW and ΔTg methods. The comparison plot showed that KWW data are directly proportional to the ½ power of ΔTg data, after adjusting for a small offset. A moderate positive correlation was observed between the onset of crystallization and the KWW data. Structural relaxation times may be useful predictor of physical stability of co-amorphous systems.
In this work, sensitive detection of dengue virus type 2 E-proteins (DENV-2 E-proteins) was performed in the range of 0.08 pM to 0.5 pM. The successful DENV detection at very low concentration is a matter of concern for targeting the early detection after the onset of dengue symptoms. Here, we developed a SPR sensor based on self-assembled monolayer/reduced graphene oxide-polyamidoamine dendrimer (SAM/NH2rGO/PAMAM) thin film to detect DENV-2 E-proteins. Surface characterizations involving X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) confirms the incorporation of NH2rGO-PAMAM nanoparticles in the prepared sensor films. The specificity, sensitivity, binding affinity, and selectivity of the SPR sensor were then evaluated. Results indicated that the variation of the sensing layer due to different spin speed, time incubation, and concentration provided a better interaction between the analyte and sensing layer. The linear dependence of the SPR sensor showed good linearity (R2 = 0.92) with the lowest detection of 0.08 pM DENV-2 E-proteins. By using the Langmuir model, the equilibrium association constant was obtained at very high value of 6.6844 TM-1 (R2 = 0.99). High selectivity of the SPR sensor towards DENV-2 E-proteins was achieved in the presence of other competitors.