Fourier Transform Infrared Spectra Research Articles

Evaluating mechanism of banana pseudo-stem retting using seawater: A cost-effective surface pre-treatment approach

Retting has been employed to extract natural fibers from agricultural wastes as a biological and cost-effective approach for centuries. With its global abundance, banana pseudo-stem is a promising agro-waste for lignocellulosic fiber extraction. In this study, fibers were extracted from the pseudo-stems after being pre-treated under four conditions using seawater at room temperature for up to 35 d Bacterial isolation from the fresh seawater sample and screening for ligninolytic ability were conducted. Bacterial load as well as laccase and manganese peroxidase enzyme activity profile assay during the retting duration were analyzed. Fourier transform infrared (FT-IR) and X-day diffraction (XRD) analyses were also examined for both pre-treated and untreated extracted fibers. The results shows that six out of the eight bacterial isolates had the ability to degrade lignin. The treatments (Raw stem + Raw seawater) and (Autoclaved stem + Raw seawater) recorded the highest viable bacterial load of 9.24 × 102 and 4.46 × 102 CFU, respectively, on the 14th day of the retting process. Additionally, the highest laccase and manganese peroxidase enzymes activity was recorded for (Raw stem + Raw seawater) and (Autoclaved stem + Raw seawater) treatments in the second to the third week. The FT-IR spectra of the pre-treated fibers revealed relative reductions in peaks attributed to polysaccharides and other amorphous substances for all retting conditions. The XRD diffractogram revealed that the crystallinity index (CI) of pre-treated fibers increased in all seawater retting treatment conditions. However, the CI for fibers pre-treated under enzymatic conditions were enhanced even after five weeks. Sequence analysis for selected bacterial isolates showed homology to sequences of Bacillus velezensis, Shewanella sp. L8–5, and Citrobacter amalonaticus and Bacillus subtilis j8 strain. From these findings, it was suggested that physical, biological, and chemical actions were collectively involved in the seawater retting process of banana pseudo-stems.

Catalytic Degradation Efficacy of Silver Nanoparticles Fabricated Using Actinidia deliciosa Peel Extract

The preparation of metallic nanoparticles using green synthetic approaches and its application toward the efficient degradation of environmentally hazardous dyes constitutes an attractive alternative to currently employed methods. In the current report, the green synthesis of silver nanoparticles (AgNPs) was successfully achieved using Actinidia deliciosa (kiwifruit) peel aqueous extract as a bioreducing agent under optimized synthesis conditions. The experimental parameters were optimized in terms of reactant ratio, reaction temperature, and reaction time. The biogenic nanoparticles exhibited SPR absorption band at λmax 480 nm. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) images revealed quasispherical monodisperse nanoparticles which were 36 nm in diameter. The hydrodynamic diameter of the nanoparticles was 106 nm as determined by dynamic light scattering, and the highly negative ζ-potential (−34 mV) supported its superior colloidal stability. Energy dispersive X-ray confirmed that silver is a major constituent of the nanoparticles. X-ray diffraction (XRD) diffractograms confirmed the crystallinity of the nanoparticles and its face-centered cubic (fcc) lattice structure. The functional groups in the plant’s phytochemicals facilitating the reduction of Ag+ ions and stabilization of the formed AgNPs were identified by fourier transform infrared (FTIR) spectroscopy. In specific, the bands in the FTIR spectra at 3,412, 1,618, 1,419, and 1,237 cm−1 suggested the presence of phenolic compounds. Phytochemical analysis by colorimetric assays revealed that the kiwifruit peel extract was rich in phenolic compounds. When evaluated in the catalytic degradation of organic dyes, the biosynthesized AgNPs induced instant and complete discoloration of the methylene blue dye when 1.6 mg of nanoparticles was used. At a lower dose of AgNPs (0.4 mg), 80% degradation of the dye occurred after 3 hr of treatment. The degradation reaction followed second-order kinetics with a rate constant of 0.01083 mM−1s−1. The current study highlights the immense potential of the prepared nanoparticles as efficient catalysts for the degradation of hazardous organic dyes such as methylene blue and presents an intriguing argument for investigating the catalytic efficiency of the biogenic AgNPs for the degradation of other structurally different dye pollutants.

Evaluation of a novel composite of expanded polystyrene with rGO and SEBS-g-MA.

This study displays the effect of reduced graphene oxide (rGO) nanofiller and polystyrene-b-poly(ethylene-ran-butylene)-b-polystyrene-grafted maleic anhydride (SEBS-g-MA) on the optical, thermal, and mechanical features of expanded polystyrene (EPS). First, the thin films of pristine EPS and composites were prepared using solution cast method. The prepared films were subjected to fourier-transform infrared (FTIR), SEM, UV-visible spectrophotometer, thermogravimetric analysis/differential scanning calorimetry, and universal testing machine for structural, morphological, optical, thermal, and mechanical characterizations. Optical study revealed a significant increase in refractive index and absorption of composites than EPS. Indirect band-gap energy of EPS (~4.08 eV) was reduced to ~1.61 eV for rGO composite and ~ 2.23 eV for composite composed of rGO and SEBS-g-MA. Thermal analyses presented improvement in characterization temperatures such as T10, T50, Tp, Tm, and Tg of composites, which ultimately lead to the thermal stability of prepared composites than pristine EPS. Stress-strain curves displayed higher yield strength (46.62 MPa), Young's modulus (96.29 MPa), and strain at break (0.54%) for EPS+rGO composite than pure EPS having stress at break (1.01 MPa), Young's modulus (12.44 MPa), and strain at break (0.08%). Moreover, ductility with relatively higher strain at break (0.61%) and lower Young's modulus (79.32 MPa) and yield strength (32.98 MPa) was noticed in EPS+rGO+SEBS-g-MA composite than EPS+rGO composite film. Morphological analysis revealed a change in globular morphology of EPS and inhomogeneous dispersion of rGO in EPS to homogeneously dispersed rGO in EPS matrix without globules owing to the addition of SEBS-g-MA. The increase in compatibility of EPS and rGO due to SEBS-g-MA was also observed in FTIR spectra. RESEARCH HIGHLIGHTS: Here, the solution casting approach was used to create the composite film of EPS and rGO with globules of various sizes. After adding SEBS-g-MA, the shape altered to globular free films exhibiting homogenous dispersion of rGO in EPS matrix. An optical investigation showed that composite materials had a significantly higher refractive index and absorption than EPS. The optical, thermal, and mechanical investigations suggest that the produced composites may be a great substitute for virgin EPS, allowing for a wider range of applications.

Copper nanoparticle biosynthesis and characterization utilizing a bioflocculant from Kytococcus sedentarius

Abstract The application of microbial flocculants in nanoparticle synthesis is attracting scientists to utilize them due to their eco-friendliness. This study was mainly focused on biosynthesizing and characterizing copper nanoparticles from a non-pathogenic microorganism Kytococcus sedentarius to produce bioflocculant. The formed copper nanoparticles (CuNPs) were analyzed using UV–vis spectroscope (UV–vis), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffractometer (XRD) and thermo-gravimetric analysis (TGA). After extraction and purification, 2.4 g was produced from bioflocculant in a 1 L culture fermentation mixture. During CuNP biosynthesis, a blue color change was obtained after 24 h of incubation indicating their successful formation. A variety of elements namely, C, O, Cu, P, Ca, Mg and Al were found in the as-synthesized CuNPs with 25.23 % (wt) carbon, 20.13 % (wt) of oxygen and 23.37 % (wt) of Cu element. SEM and TEM images of the product depicted it to be agglomerated with different size and shapes. The TGA showed the CuNPs to be thermal stable as 70 % weight was retained at 900 °C with 30 % weight lost. FT-IR spectrum of the biosynthesized CuNPs contains a variety of functional groups related to sugar and proteins namely, hydroxyl, amine, carboxyl groups and a typical Cu–O bond at 559 cm−1. The crystallite size was estimated to be 28.3 nm, which is in line with JCPDS card no. 89–5899 of copper standard confirming the correct peak orientation. UV–vis analysis revealed the absorption peak to be 275 nm which confirms synthesis of the CuNPs using a bioflocculant.

Preparation and evaluation of naproxen ternary solid dispersion using genetically modified cassava starch and hydroxypropyl methyl cellulose

Background: Naproxen has poor aqueous solubility and high permeability, making its formulation into oral dosage form challenging. The objective of this work was to enhance naproxen aqueous solubility by formulating it into solid dispersion (SD) using genetically modified cassava starch (GMCS) and hydroxypropyl methyl cellulose (HPMC) as polymers, and polysorbate-80 as surfactant.Materials and Methods: Naproxen SD was prepared by solvent evaporation. Different polymer-drug ratios (1:1, 2:1, 3:1 and 4:1) were used. The SDs were evaluated for solubility and the optimum formulation (S2) subjected to Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). Pure naproxen tablets (TN) and S2 tablets (T2) were directly compressed and assessed for hardness, friability, weight uniformity, disintegration and dissolution times.Results: The SD of polymer/drug ratio 2:1 and GMCS/HPMC proportion 2:1 had the highest solubility with the polymers showing synergism. Incorporating polysorbate-80 improved solubility by over 20 folds. SEM micrograph of the SD appeared smooth and spherical. DSC thermogram indicated a reduction in crystallinity of naproxen. FTIR spectrum showed no evidence of interaction with the polymers. T2 and TN tablets showed acceptable hardness, disintegration time and weight uniformity. The t50 and t90 dissolution values for T2 were 4.9 and 37.7 minutes respectively which were considerably lower than that of TN (28.57 and 63.42 minutes).Conclusion: Naproxen solubility was enhanced by solid dispersion formulation using genetically-modified cassava starch/HPMC blend. Synergistic effect in the improvement of naproxen solubility was established between the polymers. Inclusion of polysorbate-80 also improved naproxen solubility in the solid dispersion.

Aluminum zirconate nanoparticles in etch and rinse adhesive to caries affected dentine: An in-vitro scanning electron microscopy, elemental distribution, antibacterial, degree of conversion and micro-tensile bond strength assessment.

To incorporate different concentrations of Al2O9Zr3 (1%, 5%, and 10%) nanoparticles (NP) into the ER adhesive and subsequently assess the impact of this addition on the degree of conversion, μTBS, and antimicrobial efficacy. The current research involved a wide-ranging examination that merged various investigative techniques, including the application of scanning electron microscopy (SEM) for surface characterization of NP coupled with energy-dispersive x-ray spectroscopy (EDX), Fourier-transform infrared (FTIR) spectroscopy, μTBS testing, and microbial analysis. Teeth were divided into four groups based on the application of modified and unmodified three-step ER adhesive primer. Group 1 (0% Al2O9Zr3 NPs) Control, Group 2 (1% Al2O9Zr3 NPs), Group 3 (5% Al2O9Zr3 NPs), and Group 4 (10% Al2O9Zr3 NPs). EDX analysis of Al2O9Zr3 NPs was performed showing elemental distribution in synthesized NPs. Zirconium (Zr), Aluminum (Al), and Oxides (O2). After primer application, an assessment of the survival rate of Streptococcus mutans was completed. The FTIR spectra were analyzed to observe the characteristic peaks indicating the conversion of double bonds, both before and after the curing process, for the adhesive Etch and rinse containing 1,5,10 wt% Al2O9Zr3 NPs. μTBS and failure mode assessment were performed using a Universal Testing Machine (UTM) and stereomicroscope respectively. The μTBS and S.mutans survival rates comparison among different groups was performed using one-way ANOVA and Tukey post hoc (p = .05). Group 4 (10 wt% Al2O9Zr3 NPs + ER adhesive) specimens exhibited the minimum survival of S.mutans (0.11 ± 0.02 CFU/mL). Nonetheless, Group 1 (0 wt% Al2O9Zr3 NPs + ER adhesive) displayed the maximum surviving S.mutans (0.52 ± 0.08 CFU/mL). Moreover, Group 2 (1 wt% Al2O9Zr3 NPs + ER adhesive) (21.22 ± 0.73 MPa) samples displayed highest μTBS. However, the bond strength was weakest in Group 1 (0 wt% Al2O9Zr3 NPs + ER adhesive) (14.13 ± 0.32 MPa) study samples. The etch-and-rinse adhesive exhibited enhanced antibacterial activity and micro-tensile bond strength (μTBS) when 1% Al2O9Zr3 NPs was incorporated, as opposed to the control group. Nevertheless, the incorporation of Al2O9Zr3 NPs led to a decrease in DC. RESEARCH HIGHLIGHTS: 10 wt% Al2O9Zr3 NPs + ER adhesive specimens exhibited the minimum survival of S.mutans. 1 wt% Al2O9Zr3 NPs + ER adhesive samples displayed the most strong composite/CAD bond. The highest DC was observed in Group 1: 0 wt% Al2O9Zr3 NPs + ER adhesive.

Green synthesis of silver nanoparticles using mature-pseudostem extracts of Alpinia nigra and their bioactivities

Abstract Green synthesis of silver nanoparticles (AgNPs) employing agricultural wastes as plant extracts to improve environmental benignity and also economic value added is the highlight of this research. The mature pseudostem of Alpinia nigra is an unbeneficial raw material discarded from several food ingredients and medicinal formulas. Therefore, this research focused on condition optimization for AgNP synthesis with ecofriendly techniques using A. nigra mature-pseudostem extracts and evaluation of their antioxidant, antibacterial activities, and toxicity with brine shrimp lethality assay (BSLA). The optimal reaction conditions were achieved by using 5 mM silver nitrate (AgNO3) solution with a volume ratio of 2:8 for the extract to AgNO3 at pH 12 under room temperature. The morphology and crystalline phase of the generated AgNPs were characterized using UV–visible spectrophotometry, field emission-scanning electron microscope (FE-SEM), energy dispersive X-ray, X-ray diffraction, and Fourier transform-infrared (FTIR) techniques. The FE-SEM analysis exposed spherical shapes with an average diameter of approximately 49 nm. The XRD analysis indicated their face center cubic structure, and the FTIR spectra confirmed that phytochemicals from A. nigra extract promoted the synthesis of AgNPs. In particular, the biosynthesized AgNPs presented potential antibacterial activity against both Staphylococcus aureus and Escherichia coli and effective antioxidant capacity using the DPPH radical scavenging assay. Additionally, non-toxic desired AgNPs were confirmed with BSLA.

Graphene aerogel based positive electrode for lithium ion batteries

In this study, a composite of LiNi0.8Mn0.1Co0.1O2 nanoparticles (nNMC-811) supported by three-dimensional (3D) graphene aerogel (GA) was prepared to increase the practical energy density and performance capability of high nickel cathodes. The porous LiNi0.8Mn0.1Co0.1O2 nanoparticle/graphene aerogel (nNMC-811/GA) composite is composed of nNMC-811 and graphene that act as a bridge for electron transfer and acceleration of lithium ion diffusion. nNMC-811 and nNMC-811/GA cathodes characterization data with techniques including X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectra (FT-IR) and X-ray photoelectron spectroscopy (XPS) are discussed. Both Field Emission Scanning Electron Microscopy (FE-SEM) and Transmission Electron Microscopy (TEM) made clear observations of the uniform distribution of the cathode active powders over the 3D graphene aerogel structure. The electrochemical performance of the nNMC-811 and nNMC-811/GA cathodes was evaluated by the galvanostatic charge-discharge measurement between 2.5 V and 4.5 V at room temperature using a computer-controlled battery tester. In addition, variable speed capacity ratios (C-rate), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) analyzes were also performed. nNMC-811/GA hybrid composite structure delivers a specific capacity of 183.15 mAhg−1 at C/2 after the 500th cycle. It is understood from the FE-SEM images taken after the cycle that there is no deterioration in the structure. According to results, it was observed that the 3D porous structure of the nNMC-811/GA composite facilitated the mobility of Li+ ions, and the excellent electrochemical performances of the cathodes were improved due to the increasing defects as well as the electrical conductivity of GA.

The characterization of diamond single crystal growing along (100) after annealing treatment under high pressure and high temperature

Diamond has many desirable properties. In this study, temperature gradient method was used to prepare a series of type Ib diamond single crystals, which were processed again to obtain and characterize Type IaA diamonds with even more desirable properties. Before annealing, Fourier-transformed infra-red(FTIR) spectra of diamond showed peaks at 1130 cm−1 and 1344 cm−1; After annealing, the peak at 1282 cm−1 was appeared in FTIR spectra of diamonds This data indicated that the isolated nitrogen in diamond aggregated after high-pressure and high-temperature (HPHT) method annealing experiment. Moreover, photoluminescence (PL) spectra suggested that no nitrogen-related color centers existed in the diamond before annealing. In contrast, after annealing, a peak at 637 nm appeared in the PL spectra, indicating the appearance of NV−colors centers type Ib diamond post-annealing. The experimental results show that type Ib diamond crystals can be decolorized after 60 min of annealing under 7 GPa and 1850 °C, which makes part of the area transparent. Under 7 GPa and 2100 °C, type Ib diamond crystals can produce NV color center when annealed for 3 min. With increasing annealing temperature and prolonged annealing duration, the density and size of etch pits on the crystal surface escalated. Therefore, this study provides a guideline for the decolorization of diamonds by HPHT annealing. Moreover, this study also reports a method to change the crystal type and obtain NV color centers under ultra-high-temperature annealing conditions of 7 GPa pressure and 2100 °C temperature, which can be applied to develop quantum materials.

Tailoring the graphene framework by embedding Nb2O5 and silver nanoparticles for electrodes in energy storage applications

In this study, Nb2O5/GNs and Ag/GNs-based nanocomposites were synthesized via a facile single-step hydrothermal approach. Using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Raman spectroscopy, fourier-transform infrared (FTIR) spectroscopy, and UV–vis spectroscopy, the morphology, functional groups, structure, and optical and electrical properties of the as-prepared materials were examined. XPS studies show the predominant signal at 284.8 eV is attributed to the sp2 carbon atoms (C 1) that comprise graphitic areas, indicating that the majority of the C atoms are arranged in a honeycomb lattice. FTIR spectrum confirms bonding, such as CO, CH2, CO, CC, OH, AgO, and NbONb in the nanocomposite. Further, the specific capacitance (Csp) of the Nb2O5/GNs and Ag/GNs was calculated 603 Fg−1 and 810 Fg−1 at different current densities, The Nb2O5/GNs exhibit 109 Wh/kg and 2180 W/kg energy and power density, respectively. However, the Ag/GNs electrode exhibited an energy density of 145.8 Wh/kg and a power density of 3645 W/kg, with cyclic stability retentions of 93.06 % and 97.02 %, respectively. The capacitance retention finished at 1000 cycles. Moreover, the achieved resistance from the I–V characteristics curve shows enhanced electrical conductivity of synthesized nanocomposites. These results suggested that the materials can have bright future in next-generation energy storage devices.

Synthesis of biopolymer blends nanocomposites embedded with mono-(Ag, Fe) and bi-(Ag-Fe) metallic nanoparticles using an eco-friendly approach for antimicrobial activities.

Plant-mediated solution casting is used to develop eco-friendly polymer blend nanocomposites from polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP) doped with Silver (Ag), Ferrous (Fe) monometallic and Silver-Ferrous (Ag-Fe) bimetallic nanoparticles (NPs). These nanocomposites were studied to understand their electromagnetic interface (EMI) shielding efficiency and antimicrobial activities, besides evaluating their physical and chemical properties. The Fourier transform infrared (FTIR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and energy dispersive X-ray (EDX) characterization techniques were used to examine the interactions between the polymers, the presence of silver and ferrous particles in the composites, the crystallinity shift, the surface morphology, the shape and size of the nanoparticles and the distribution of the nanoparticles in the composites. The FTIR spectra showed the interactions among the components of the composites. According to XRD spectra, the incorporation of nanoparticles into the PVA polymer significantly reduced the crystalline character of the polymer from 0.38 to 0.24 for the composition consisting of silver and iron nanoparticles in equal proportion. The results from SEM, EDX and XRD corroborate the presence of nanoparticle forms. The thermogravimetric analysis (TGA) tests reveal that the thermal stability of bimetallic composites is greater than that of monometallic composites. The tensile properties showed that the addition of nanoparticles to the PVA/PVP polymer matrix increased its mechanical strength from 59.3MPa to 85.5MPa. We examined its efficacy against Escherichia coli, Staphylococcus aureus and Candida albicans as microorganisms. Good antibacterial and antifungal activity was observed. The bimetallic composites demonstrated greater activity than monometallic composites against these bacterial and fungal species. All bimetallic nanocomposites have shown enhanced, loss due to reflection, loss due to absorption, and the total EMI shielding efficiency at 8GHz (X-band) and 16GHz (Ku-band) frequency. All these results ratify, that these newly developed bio nanocomposites are most suitable in many applications, in EMI shielding, nanotechnology, and medical fields.

Microencapsulation by coacervation: Physicochemical and sensory properties of food flavorings

Coacervation is a low-energy method that is ideal for encapsulating heat-sensitive materials, e.g., limonene, citral, linalool, and isoamyl acetate. 
 This research used a simple coacervation method to prepare flavoring beads with alginate and Tween 80. The methods of scanning electron microscopy (SEM) and fourier transform infrared (FTIR) spectroscopy made it possible to study the morphology and structure of the flavoring beads. After the extraction, the flavor retention and structure were described using the method of gas chromatography with mass spectrometry (GC-MS). 
 The microcapsules demonstrated a retention rate of 99.07–99.73% while the encapsulation efficiency remained as high as 96.40–97.07%. The microcapsules had a mononuclear structure and ranged from spherical to elongated ellipsoids; they were sealed without agglomeration. The particle size was below 1000 µm. The GC-MS chromatograms detected neither structural changes nor any new compounds. The FTIR spectra were similar to the control but demonstrated slight shifts, which suggested fundamental structural changes caused by the coacervation. We also fortified sponge cake and jelly with flavoring beads. The sensory analysis of the sponge cake samples revealed no significant differences compared to the control. All the fortified jelly samples had higher scores for smell, taste, texture, and overall preference than the control. 
 The coacervation method proved to be an excellent solution for the problem of heat-sensitive flavorings that often lose quality or sensory attributes in food products that undergo extensive thermal treatment.

FTIR Spectroscopy and Blood-Derived Extracellular Vesicles Duo in Alzheimer's Disease.

Alzheimer's disease (AD) diagnosis is difficult, and new accurate tools based on peripheral biofluids are urgently needed. Extracellular vesicles (EVs) emerged as a valuable source of biomarker profiles for AD, since their cargo is disease-specific and these can be easily isolated from easily accessible biofluids, as blood. Fourier Transform Infrared (FTIR) spectroscopy can be employed to analyze EVs and obtain the spectroscopic profiles from different regions of the spectra, simultaneously characterizing carbohydrates, nucleic acids, proteins, and lipids. The aim of this study was to identify blood-derived EVs (bdEVs) spectroscopic signatures with AD discriminatory potential. Herein, FTIR spectra of bdEVs from two biofluids (serum and plasma) and distinct sets of Controls and AD cases were acquired, and EVs' spectra analyzed. Analysis of bdEVs second derivative peaks area revealed differences between Controls and AD cases in distinct spectra regions, assigned to carbohydrates and nucleic acids, amides, and lipids. EVs' spectroscopic profiles presented AD discriminatory value, supporting the use of bdEVs combined with FTIR as a screening or complementary tool for AD diagnosis.

Pharmacological Effect of In Vitro Antioxidant Property and Green Synthesis of Silver Nanoparticles (AgNPs) Utilizing Murraya koenigii Antibacterial Application

ABSTRACT Background: Nonessential heavy metals pose a significant threat to human health due to their toxicity. Mercury, in particular, is identified as a hazardous metal. The study aims to detect mercury using colorimetric analysis with Murraya koenigii, emphasizing the eco-friendliness of the method. Aims and Objectives: The primary objective is to detect mercury using a colorimetric analysis method employing Murraya koenigii. Additionally, the study aims to investigate the eco-friendliness of this detection method. Materials and Methods: Colorimetric analysis was conducted using Murraya koenigii to detect mercury. Ultraviolet-visible (UV-vis) spectroscopy was employed to detect the formation of silver nanoparticles (AgNPs), with a characteristic surface plasmon resonance (SPR) band observed. X-ray diffraction (XRD) data analysis was performed to determine the crystalline nature and size of AgNPs. Scanning electron microscopy (SEM) was utilized to visualize the morphology of AgNPs. Fourier transform infrared (FTIR) spectroscopy was employed to identify functional groups involved in reducing silver ions. Antibacterial properties of synthesized AgNPs were tested against various microorganisms, including Escherichia coli, Staphylococcus aureus, Streptococcus mutans, and Enterococcus faecalis. Results: Mercury was successfully detected using colorimetric analysis with Murraya koenigii. Formation of AgNPs was confirmed by UV-vis spectroscopy, with a characteristic SPR band at 418 nm. AgNPs were found to be crystalline with an average size of 5.20 nm, as determined by XRD analysis. SEM images revealed spherical and polycrystalline AgNPs. FTIR spectra indicated the involvement of the -OH group of compounds in the extract in reducing silver ions. Synthesized AgNPs exhibited antibacterial properties against various microorganisms. Conclusion: A sustainable and eco-friendly method for synthesizing AgNPs using Murraya koenigii extract was successfully developed. This method not only detected mercury but also demonstrated antibacterial properties against various microorganisms. The study underscores the health implications of nonessential heavy metals, emphasizing the importance of eco-friendly detection and mitigation methods.

Situ synthesis and characterization of polypyrrole/ZnO Nanocomposites for optical and photocatalytic activity

In situ polymerisation process used for manufacturing polypyrrole (PPy) nanoparticle-reinforced various doping concentration of zinc oxide (ZnO NPs) nanocomposites. Fourier transform infrared(FTIR), Scanning electron microscopy(SEM), Photo luminescence (PL) and UV-vis spectroscopy was used to characterise the polymer nanocomposite. The ZnO nanoparticles are distributed throughout PPy matrix as shown in the SEM pictures of the nanocomposites. Distinctive peaks of Pure PPy and metal oxide bond of ZnO are as displayed in the FTIR spectra. Optical property of PPy, ZnO and PPy/ZnO was studied by using PL and UV-DRs spectrophotometer. These outcomes demonstrated that the synthesised PZ30 nanoparticles could potentially use in the treatment of wastewater.

The combination of Fourier-transform infrared spectroscopy with pattern recognition techniques for classification and discrimination of red snapper fish oils.

Fish oils are good sources for essential fatty acids such as omega-3 and omega-6 fatty acids needed to human growth. Indonesia is rich in fish species and among this, red snapper fish (Lutjanus sp.) can be extracted to get red snapper fish oils (RSFOs). The aim of this study was to classify and discriminate RSFO from different origins using Fourier-transform infrared (FTIR) spectra and pattern recognition techniques. All of the RSFO's FTIR spectra were very similar. The FTIR vibrations showed the presence of triglycerides as the main composition in fish oils. Principal component analysis (PCA) could separate the RSFO according to sample origin. Supervised pattern recognition of partial least square-discriminant analysis (PLS-DA) and sparse PLS-DA (sPLS-DA) successfully discriminated and classified different Lutjanus species of fish oils obtained from different origins. The vibration of functional groups at 1711, 1653, 1745, and 3012 per cm were considered for their important contributions in discriminating of Lutjanus species (variable importance in projection, variable importance in the projection score >1). Fish oils obtained from the same species were classified into the same class indicating similar chemical compositions. Among the three pattern recognition techniques used, sPLS-DA offers the best model for the discrimination and classification of Lutjanus fish oils. It can be concluded that FTIR spectroscopy in combination with the pattern recognition technique is the potential to be used for of fish oil authentication to verify the quality of the fish oils. It can be further developed as a rapid and effective method for fish oil authentication.

Synthesis and Characterization of Hydroxyapatite/Alginate Composites: Study of pH and Sintering Influenced on the Structural, Morphological, and Clindamycin Release Behavior

The hydroxyapatite/alginate (HAp/Alg) composite was synthesized using an in-situ precipitation route. The effect of pH (8, 9, 10, and 11) and calcination temperature (300, 500, 700, and 900 °C) were studied by characterization techniques such as X-ray diffraction (XRD), Fourier-transform infrared (FTIR), and scanning electron microscopy with energy-dispersive X-ray (SEM with EDAX). XRD results show the hexagonal crystal system of HAp for each pH value and the biphase (HAp and whitelockite) for the sintering temperature at 700 and 900 °C. The FTIR spectra show no impurity peaks. SEM images revealed spherical-like (HAp/Alg-11) and flake-like (HAp/Alg-900) particles with good homogeneity, size, and shape that could be notable for biomedical utilization, such as drug delivery material. Drug loading and release ability of pure HAp, HAp/Alg-11, and HAp/Alg-900 composites have been investigated with clindamycin hydrochloride as the drug model. The maximum clindamycin HCl release from HAp, HAP/Alg-11, and HAp/Alg-900 reached 74.48, 92.75, and 69.65% in the 8th hour. HAp/Alg-11 has the highest release because it has the largest surface area of 162.584 m2/g. Antibacterial test results showed HAp/Alg-11 has antibacterial activity against Staphylococcus aureus and Escherichia coli, confirming that HAp/Alg-11 composite has the potential to be applied as drug delivery.

Pemanfaatan Ekstrak Daun Sirih Hijau (Piper Betle Linn.) sebagai Capping Agent dalam Green Synthesis Spinel Ferit ZnFe2O4 untuk Remediasi Fenol dalam Air dan sebagai Anti Bakteri

The spinel ferrite material ZnFe2O4 was synthesized using a green synthesis approach by the hydrothermal method. In the synthesis, 2M NaOH was used as a mineralizer and betel leaf extract with varying volumes of 1, 3, 5, and 7 mL as a capping agent, then continued with calcination at 500, 600, and 700°C. Several devices, such as XRD, FT-IR, SEM-EDX, DRS-UV-Vis, and VSM, were used to characterize the synthesized ZnFe2O4 material. The pattern of XRD indicated that the ZnFe2O4 material has a cubic structure, where the increase in crystal size was after calcination. The Fourier Transform Infra-Red (FT-IR) spectrum shows the Fe-O interaction at wave numbers 427-417 cm-1, which is located on the octahedral side, while the Zn-O interaction at wave numbers 534-510 cm-1, which is located on the tetrahedral side in spinel ferrite structure. From the DRS UV-Vis spectrum pattern and band gap values, it was found that the material absorbs light in the visible region. Scanning Electron Microscope (SEM) images show that the morphology of the synthesized material is circular. The Vibrating Sample Magnetometer (VSM) hysteresis curve shows that the synthesized ZnFe2O4 has paramagnetic properties. The synthesized ZnFe2O4 material has photocatalytic activity towards phenolic compounds with a degradation percentage reaching 62.2%, and this material is active as an antibacterial with an inhibition area of 14.4 for S. aereus bacteria.

The nanoparticle formula optimization from Temulawak extract (Curcuma xanthorrhiza) as adjuvant therapy

Temulawak extract was synthesized using temulawak sodium alginate. The nanoparticle formula was obtained by combining the characteristics of temuwak extract and temusawak. The microbeads were characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. The size of Alg-Curcuma was measured at SEM. The particle size distribution of the sample was analyzed using FTIR spectra. The results showed that the size of the resulting beads is microparticle in size. It was found that the temurawak extract is a good candidate as an anticancer agent. Therefore, there are several recommendations that can be done to optimize the synthesis of the material. The study reported that the recommended parameter is 12.5 kV with a flow rate of 0.1 mL/h (first batch synthesis).

Physicochemical Effects of PEG Content in Alginate-based Double Network Hydrogels as Hybrid Scaffolds

This study aims to prepare a double-network hydrogel as hybrid networks bearing both natural and synthetic polymers to obtain scaffolds with increased swelling capacity and tunable mechanical and morphological properties. Physically cross-linked alginate hydrogel was reinforced with various ratios of Poly(ethylene glycol) (PEG) polymers which were chemically gellated via UV light exposure with a water soluble initiator. Physicochemical properties of the resulting hydrogels were systematically investigated via Fourier-transform infrared (FT-IR) spectroscopy for chemical composition and Scanning Electron Microscopy (SEM) for their morphological features like porosity. Furthermore, the effect of PEG amount in the final hydrogel (10, 20 and 40%) on swelling capacity was evaluated as well as the rheological properties. Prepared double-network hydrogels were demonstrated to be composed of both natural alginate polymer and synthetic PEG chains in FT-IR spectrum. Although 10%PEG containing hydrogel was not significantly different in terms of swelling capacity from the alginate hydrogel alone, increasing PEG amount seems to have improved the swelling ability. Comparative reological studies presented that introducing covalently cross-linked PEG network into alginate one increased crosspoint of storage and loss moduli almost 12 times more providing a stiffer scaffold. Increasing PEG content decreased the pore size on SEM images, indicating more crosslinking points in hydrogel structure.