Sample pH Research Articles

Development of Dusun Traditional Fermented Fish (Bosou Ikan) Using Different Concentrations of Tuhau (Etlingera coccinea)

This study aimed to determine the best formulation of Dusun traditional fermented fish (Bosou ikan) through sensory evaluation employing a 9-point hedonic test. Various concentrations of Etlingera coccinea, ranging from 0% to 8% w/w, were incorporated into fermented fish samples. Results revealed that the formulation containing 2% E. coccinea (F1) consistently exhibited superior sensory attributes, maintaining the traditional appearance while enhancing aroma, taste, and overall acceptability. Statistical analysis using the Friedman test confirmed F1's superiority, showing the lowest mean rank among alternatives (p<0.05). Proximate analysis of F1 demonstrated notable increases in ash, crude fat, crude fiber, and crude protein content compared to Control Bosou ikan formulations, indicating enhanced nutritional profiles. Shelf-life analysis demonstrated a more controlled trend in reducing total viable count and total yeast and mold counts for the F1 formulation compared to the control, suggesting a potential influence of E. coccinea in inhibiting excessive microbial proliferation. Comparison of microbial loads between raw and cooked samples revealed that cooking effectively eliminated microbial counts, reaching safety consumption levels of 4 log10 CFU/g (total yeast and mold) and 6 log10 CFU/g (total viable count). The decrease in pH of raw and cooked samples over one month was attributed to increased acidity resulting from the activities of Lactobacillus sp., which utilizes carbohydrates in the medium to produce lactic acid. The study highlights that the F1 formulation with 2% Etlingera coccinea offers the most favourable sensory characteristics, proximate analysis, and microbial quality, providing valuable insights for product development in Bosou ikan production.

Chemical Profile, Antioxidants, and Enzymatic Activity of the Kombucha Tea Beverages as a Potential Anti-obesity Beverage

This study aimed to investigate the chemical profile, antioxidant activity, and enzyme inhibition of black tea kombucha and kombucha without tea, as well as the relationship between these three parameters. Both kombuchas of different fermentation times (1, 7, 14, 21 days) were analysed. The pH and total soluble solids (TSS) of both samples decreased gradually with fermentation time. The scavenging activity (DPPH), total phenolic content (TPC), and total flavonoid content (TFC) of black tea kombucha were significantly higher than kombucha without tea. The porcine pancreatic lipase (PPL) inhibition of both samples increased gradually with fermentation time. Significant differences (p < 0.05) were observed in pH, TSS, and PPL inhibition from the beginning to the end of fermentation in black tea kombucha, while for kombucha without tea, significant differences (p < 0.05) were observed in pH, TFC, and PPL inhibition. Moreover, significant differences (p < 0.05) were observed in all parameters except pH between the two samples at the end of fermentation. The Pearson correlation revealed kombucha's lipase inhibition was correlated with its chemical profile, not with antioxidant activity. These findings indicate the anti-obesity potential of kombucha, highly associated with kombucha’s chemical profile.

High Performance Thin Layer Chromatography (HPTLC) Analysis of Anti-Asthmatic Combination Therapy in Pharmaceutical Formulation: Assessment of the Method's Greenness and Blueness.

A cost-effective, selective, sensitive, and operational TLC-densitometric approach has been adapted for the concurrent assay of Hydroxyzine Hydrochloride (HYX), Ephedrine Hydrochloride (EPH), and Theophylline (THP) in their pure powder and pharmaceutical forms. In the innovative TLC-densitometric approach, HYX, EPH, and THP were efficaciously separated and quantified on a 60F254 silica gel stationary phase with chloroform-ammonium acetate buffer (9.5:0.5, v/v) adjusted to pH 6.5 using ammonia solution as a mobile liquid system and UV detection at 220 nm. The novel TLC method validation has been performed in line with the international conference for harmonization (ICH) standards and has been effectively used for the estimation of the researched medicines in their pharmaceutical formulations without intervention from excipients. Additionally, parameters affecting the chromatographic analysis have been investigated. The new TLC approach's functionality and greenness were appraised using three modern and automated tools, namely the Blue Applicability Grade Index (BAGI), the Analytical Greenness metric (AGREE), and the Green Analytical Procedure Index (GAPI) tools. In short, the greenness characteristics were not achieved as a result of using mandatory, non-ecofriendly solvents such as ammonia and chloroform. On the contrary, the applicability and usefulness of the novel TLC approach were attained via concurrent estimation for the three drugs using simple and straightforward procedures. Moreover, the novel TLC method outperforms previously published HPLC ones in terms of the short run time per sample and moderate pH value for the liquid system. According to the conclusions of comparisons with previously recorded TLC methods, our novel HPTLC method has the highest AGREE score, so it is the greenest HPTLC strategy. Moreover, its functionality and applicability are very appropriate because of the simultaneous assessment of three drugs in one TLC run. Furthermore, no tedious and complicated extraction and evaporation processes are prerequisites.

Skin-attachable Tb-MOF ratio fluorescent sensor for real-time detection of human sweat pH

The pH of human sweat is highly related with a variety of diseases, whereas the monitoring of sweat pH still remains challenging for ordinary families. In this study, we developed a novel dual-emission Tb-MOF using DPA as the ligand and further designed and constructed a skin-attachable Tb-MOF ratio fluorescent sensor for real-time detection of human sweat pH. With the increased concentration of H+, the interaction of H+ with carbonyl organic ligand leads to the collapse of the Tb-MOF crystal structure, resulting in the interruption of antenna effect, and correspondingly increasing the emission of the ligand at 380 nm and decreasing the emission of the central ion Tb3+ at 544 nm. This Tb-MOF nanoprobe has a good linear response in the pH range of 4.12–7.05 (R2 = 0.9914) with excellent anti-interference ability. Based on the merits of fast pH response and high sensitivity, the nanoprobe was further used to prepare flexible wearable sensor. The wearable sensor can detect pH in the linear range of 3.50–6.70, which covers the pH range of normal human sweat (4.50–6.50). Subsequently, the storage stability and detection accuracy of the sensors were evaluated. Finally, the sensor has been successfully applied for the detection of pH in actual sweat samples from 21 volunteer and the real-time monitoring of pH variation during movement processing. This skin-attachable Tb-MOF sensor, with the advantages of low cost, visible color change and long shelf-life, is appealing for sweat pH monitoring especially for ordinary families.

Magnetic multi-template molecularly imprinted polymers for selective simultaneous extraction of chlorophenols followed by determination using HPLC

Magnetic multi-template molecularly imprinted polymers (M-mt-MIPs) were successfully synthesized by surface imprinting and multi-template imprinting strategy, using polydopamine coated magnetic multi-walled carbon nanotubes as supporting materials, five typical chlorophenols (CPs) as templates, methacrylic acid as functional monomer and ethylene glycol dimethacrylate as cross-linker. Compared to non-imprinted polymers (NIPs), the as-prepared M-mt-MIPs showed high adsorption capacity (32.58‒80.63 mg g−1), rapid mass transfer and specific selectivity for the five targeted CPs, which were applied as magnetic solid-phase extraction (MSPE) adsorbents. Parameters affecting MSPE efficiency were detailed investigated, such as adsorbents dosage, sample pH, extraction time, type and volume of desorption solvent and salt effect. Combined with HPLC-DAD, a simple, rapid and sensitive method was established, showing good linearity (2‒200 μg L−1), low limits of detection (0.32‒0.49 μg L−1), and high enrichment factors (35.2‒108). The developed M-mt-MIPs-MSPE-HPLC method was applied to enrich and determine CPs in tannery wastewater, wet-blue and crust leather, and satisfactory spiking recoveries were attained in the range of 73.95‒109.7% with relative standard deviations (RSDs) of 2.13–8.48%. This study provided a new alternative material and method to rapid simultaneously extract and analyze low concentration of typical CPs in complicated matrices.

The Effects of Steeping Temperature Variations on the Production of Pap (Akamu)

The effect of temperature variation on the nutritional quality of pap was studied using (AOCS) American Oil Chemists Standard Method. Pap ingredients were purchased from Amassoma ultramodern market, Bayelsa State. A thermometer was used to record an initial temperature of 80°C (Group A), 50°C (Group B) and 25°C a room temperature (Group C). After discarding the water, the cereal grains were carefully and independently cleaned with fresh water. An attrition mill was used to grind the wet grains, and the paste produced was mixed with 1000ml of purified water. A muslin cloth was used to filter the mixture’s slurry. After allowing the filter to stand for a full day, the supernatant was disposed of. In order to allow additional water to drain off, the newly created pap was wrapped inside a muslin cloth and left to stand for the following 12 hours. The proximate composition of the pap was investigated at the varying steeping temperatures. From the result it shows that the proximate composition of pap can vary depending on the steeping temperature used, it shows that the moisture content ranged from 25.51-27-52%, protein ranged from 7.79%-8.15, fibre ranged from 2.16% – 2.24%, lipid content ranged from 8.22%–13.10%, carbohydrate ranged from 48.16% – 50.60% as the steeping temperatures increased from 25-100°C. The study revealed that the steeping temperatures had an impact on the pH, moisture, fiber, and carbohydrate contents of the papa samples, but not on the lipid, protein, mineral, or nitrogen contents, which stayed mostly unchanged. In order to preserve the nutritious value of the food, it is advised that pap be produced and steeped at a lower temperature.

Characterization and optimization of magnetic molecularly imprinted nanofibers for determination of sunitinib in human serum and capsule samples

This article reports a spectrofluorometric method for the determination of sunitinib (STB) drug based on molecularly imprinted nanofibers fabricated by the electrospinning method and modified by magnetic nanoparticles as sorbent. The characterization of magnetic molecularly imprinted nanofibers (MMINs) was carried out using X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscopy (TEM), which confirmed the successful synthesis of MMINs with well-distributed magnetite nanoparticles. Drug adsorption and desorption were optimized and important parameters such as sample pH, nanofiber mass, adsorption and desorption time, eluent solvent and sample volume were analyzed. The results demonstrated that the MMINs act as a selective sorbent for STB and can be readily collected through an external magnetic field. Methanol was used as the best eluent solvent for STB desorption from MNIN. A linear correlation was observed between the STB concentrations and fluorescence intensities in the range of 0.01–15.0 mg L−1. The detection limit for this method was 0.002 mg L−1. The relative standard deviation (RSD) of 2.6 % for 1.0 mg L−1 and 1.1 % for 10 mg L−1 of STB (n = 3) were obtained, which indicates that the developed method is precise in determining STB. Human serum and capsule analysis show the applicability of the proposed sensor for real samples.

PdRuO2/PVP nanomaterial as a highly selective, stable, and applicable potentiometric sensor for the detection of Cr3+

PdRuO2/PVP nanomaterial was synthesized using a straightforward method and characterized using advanced analytical methods such as TEM, XRD, XPS, elemental mapping and SEM. The synthesized PdRuO2/PVP nanomaterial was used as an ionophore in potentiometric sensor electrodes and successfully adapted to Cr3+ ion detection in a large number of aqueous samples. Several experimental parameters of the PdRuO2/PVP sensor such as potentiometric behavior, selectivity, repeatability, response time, pH, titration, and recovery in real samples were investigated. Potentiometric behavioral characteristics were performed in the concentration range 1 × 10−6–1.0 × 10−1 M. The repeated experiments performed six times showed that there was no deviation in the measurements. The limit of detection of the PdRuO2/PVP potentiometric sensor was very low with a value of 8.6 × 10−8 M. The potentiometric measurements showed that the synthesized PdRuO2/PVP ionophore was highly effective in detecting Cr3+ in a wide pH range of 2.0–8.0 and was found to have a shelf life of over 1 year. As a result, the synthesized PdRuO2/PVP electrode material was found to be highly selective, stable, and applicable for Cr3+ detection.Graphical

Preparation of magnetic coconut clothing biochar for extracting neonicotinoid insecticides from environmental water samples

In this study, the magnetic coconut clothing biochar hybrid materials were successfully prepared by in-situ method. The obtained magnetic biochar was characterized in detail by using series of analytical techniques. The results showed that the magnetic hybrid materials presented alveolate network structures with abundant large pores and good magnetic separation ability with Fe3O4 nanoparticles obviously attached on the surface of biochar. The magnetic biochar hybrid materials were used as adsorbents during magnetic solid-phase extraction process for extracting neonicotinoid insecticides from environmental water samples. The adsorption and desorption parameters (adsorption time, elution condition, sample volume, sample pH) affecting magnetic solid-phase extraction efficiency were carefully investigated. Under the optimum conditions (adsorption for 15 min, 5 % formic acid-acetonitrile as elution condition, 50 mL of sample volume, 15 mg of magnetic biochar, pH at 5.0), the magnetic solid-phase extraction process based on magnetic coconut clothing biochar hybrid materials coupled with high performance liquid chromatography tandem mass spectrometry for enriching and detecting neonicotinoid insecticides in environmental water samples was established. The good linear relationship in the range of 0.5–200 ng mL−1 with correlation coefficients greater than 0.9989 and the lower limits of detection (0.0017–0.0069 ng·mL−1) were obtained. The recovery in the spiked water samples was in the range of 68.6 %-104.0 % with relative standard deviation from 0.4 % to 9.3 %. These results demonstrated that the established method was highly sensitive, convenient and repeatable for directly analyzing trace neonicotinoid insecticides in environmental water samples. More importantly, the novel biochar from coconut clothing was introduced into sample pretreatment to enrich trace organic pollutants.

A porous composite sorbent incorporating a metal organic framework and zinc oxide in cryogel to extract carbamate pesticides

A composite sorbent was designed and fabricated by incorporating the Materials of Institute Lavoisier (MIL-101) and zinc oxide (ZnO) into polyvinyl alcohol (PVA) cryogel. The composite sorbent was produced to extract carbamates (carbofuran, carbaryl, isoprocarb and diethofencarb) by in-syringe solid phase extraction (SPE). MIL-101 and ZnO enhanced the adsorption of the carbamates by creating π-π stacking and hydrogen bonding, while porous PVA cryogel acted as a solid support which helped to reduce backpressure in the system. The extraction of the target carbamates was optimized by varying the amount of MIL-101 and ZnO used in the sorbent fabrication, desorption conditions, sample pH, ionic strength, sample flow rate and sample volume. The extracted target carbamates were quantitatively determined using high performance liquid chromatography technique. The developed method exhibited linearity from 1.0 to 150.0 μgL−1 for all four target carbamate pesticides with a limit of detection 0.3 µg/L. The method identified carbamates in fruit juice and white wine, obtaining recoveries from 78.1 to 108.2 % and the relative standard deviation (RSD) lower than 6.3 %. The developed composite sorbent showed good accuracy, is simple to fabricate, works rapidly and can be used for 17 extraction-regeneration cycles.

Ionic-liquid/Carbowax 20 M functionalized capsule phase microextraction platform for the extraction of phosphodiesterase-5 inhibitors from human serum and urine prior to their determination by LC–MS

Capsule phase microextraction (CPME) is an efficient bioanalytical technique that streamlines the sample preparation by integrating the filtration and stirring mechanism directly into the device. A novel composite sorbent designed to be selective towards the target analytes consisting of mixed-mode sorbent chemistry synthesized by sol–gel technology is found promising and superior to the conventional C18 sorbents. Herein we describe the encapsulation of an ionic liquid (IL)/Carbowax 20M-functionalized sol–gel sorbent (sol–gel IL/Carbowax 20 M) in the lumen of porous polypropylene tubes for the capsule phase microextraction of three phosphodiesterase-5 inhibitors namely avanafil, sildenafil, and tadalafil in human serum and urine samples. The CPME device was characterized by Scanning Electron Microscopy (SEM) and Fourier-Transform Infrared Spectroscopy (FT-IR). The experimental parameters of CPME procedure (e.g. sample pH and ionic strength, extraction time, stirring rate, elution solvent and volume) were carefully optimized to achieve the highest possible extraction efficiency for the analytes. Method validation was conducted in terms of precision, linearity, accuracy, matrix effect, lower limits of quantification, and limits of detection (LOD). The method linearity was investigated in the range of 50–1000 ng mL−1 for all analytes while the precision was less than 11.8 % in all cases. For all analytes, the LOD values were 17 ng mL−1. The IL/CW 20M-functionalized microextraction capsules could be reused at least 25 times both for urine and serum samples. The green character and the applicability of the proposed method were evaluated using the ComplexGAPI and BAGI indexes. The optimized CPME protocol exhibited reduced consumption of organic solvent and generation of waste, cost-effectiveness, and simplicity. Finally, the proposed method was successfully applied to the analysis of sildenafil in human urine after administration of drug-containing formulation.

Sensitive determination of quercetin in food samples implementing magnetic dispersive solid phase extraction coupled with ion mobility spectrometry

Quercetin (QUR) is a vital flavonoid, which is found in dietary human. The quick analysis of QUR is difficult on account of utilizing complicated methods. Hence, we developed a proposed method based on ion mobility spectrometry (IMS) to evaluate the fast analysis of QUR in food samples. This analytical method combined the benefit of polypyrrole-coated magnetic dispersive solid phase extraction (MDSPE) as a sorbent phase for the QUR extraction, and also the strength of IMS for the rapid detection. Nanoparticle (NP) characterization was investigated through VSM, FT-IR, XRD, BET, and as well as FE-SEM analysis. Sample pH, amount of nanoparticles, type and volume of desorption solvent, extraction time, and desorption time as impressive parameters in MDSPE method were investigated and optimized. The calibration curve was linear in the range of 1.0–90.0 ng mL−1, with a determination coefficient (R2) of 0.9954. The limit of detection (LOD) and the limit of quantification (LOQ) for QUR were 0.31 and 1.02 ng mL−1, respectively. The RSD% of QUR through seven parallel analyses was 4.44. This analytical work was executed to quantify QUR in honey and tea samples without any derivation procedure needed. The recovery values for QUR were estimated in the range of 92.5–96.7 % using the proposed method. Also, according to the attained results from HPLC analyses, the applicability, and susceptibility of the current method was verified.

Screening of Different Fungi Strains Gongronella sp. WICC F60 and Cordyceps sp. WICC F61 for Degradation of Low-Density Polyethylene

Over the past decade, polyethylene (PE) products have become increasingly important in several industries. Their biggest concerns are plastic material degradation resistance and environmental longevity. Therefore, this study aims to find fungi that are capable of degrading low-density polyethylene (LDPE) efficiently. This study uses Gongronella sp. WICC F60, and Cordyceps sp., WICC F61. The fungi were grown on potato dextrose agar for 30 days. Following that, fungal colonies were placed in potato dextrose broth for incubation. The LDPE sample was then cultured with the fungal strain in a minimum salt medium with a 10% inoculum. After 30 days of biodegradation testing, the analysis was done. These studies measured LDPE sample weight loss, pH, and fungal biomass. It was observed that the LDPE sample weight loss increased with time until the end of inclubation. Gongronella sp. WICC F60 and Cordyceps sp. WICC F61 were able to degrade LDPE plastic. Both fungi show an increase in LDPE weight loss. However, Cordyceps sp. WICC F61 shows more efficiency in LDPE degradation compared to Gongronella sp. WICC F60. The LDPE weight loss using Gongronella sp. WICC F60 was 1.07%, which is lower than Gongronella sp. WICC F60's LDPE weight reduction of 5.56%.

Development of a Dispersive Liquid-Liquid Aerosol Phase Extraction Method for the Quantification of Ag, Cd, Cu, Ni, and Pb in Seawater by Inductively Coupled Plasma Optical Emission Spectroscopy.

The dispersive liquid-liquid aerosol phase extraction (DLLAPE) method was applied for the determination of Ag, Cd, Cu, Ni, and Pb in seawater samples by inductively coupled plasma optical emission spectroscopy (ICP-OES). Key parameters such as sample pH and extractant concentration were systematically evaluated, with ammonium O,O'-diethyldithiophosphate (DDTP) identified as the optimal chelating agent. Optimal extraction conditions were achieved at pH 2.5 for Ag, Cu, Ni, and Pb, while Cd extraction efficiency was found to be pH independent. The extractant concentration did not greatly improve the extraction efficiency. Furthermore, the influence of nebulizer gas flow rate and extraction time was evaluated, achieving the maximum extraction yield at 0.6 L min-1 and 120 s, respectively. The method was evaluated for accuracy and bias through recovery studies, and the results showed that most elements had recovery rates close to 100% with relative standard deviation values in between 3 and 9%. However, in the case of Ag and Ni, 1.184 and 1.089 correction factors were, respectively, applied to compensate for the bias. Moreover, the procedural limits of quantification (pLOQs) found for Ag, Cd, Cu, Ni, and Pb were 0.4, 0.14, 0.2, 0.2, and 0.2 μg L-1, respectively. The in-house validation of the method provided expanded uncertainty values lower than 6% for all elements except for Ag (16.6%). Finally, the application of the method to real seawater samples from coastal areas in Alicante and San Juan (Spain) confirmed its suitability for trace metal analysis in complex marine matrices, underscoring its potential for environmental monitoring and research.

Microbiological and Physicochemical Quality of Groundwater Sources in Wamakko, Nigeria

Water is an indispensable natural resource and have remained a cause for worry in both urban and rural communities in Nigeria. A total of 15 samples were obtained from different groundwater sources in Wamakko, LGA, Sokoto State, Nigeria. Physicochemical and microbiological analysis were performed on the samples to ascertain changes in the proxies and presence of indicator organisms in the water samples. The pH of the groundwater samples obtained from point 6 was observed to have a pH of 5.6 this index was far below WHO /NIS/ NAFDAC specification for potable water. Total dissolved solids (TDS) of the groundwater samples ranged from 57.6mg/L to 529.96 mg/L while samples obtained from sampling point 7 had the lowest concentration values. The concentration of phosphates in the groundwater was observed to range from 0.16±0.01a to 5.21±0.12h mg/L. Pearson Correlation showed strong correlation between turbidity and BOD of groundwater at r=0.800, Salinity and hardness of the groundwater with a correlation coefficient of 0.88 at p-value < 0.0. The samples obtained from point 6 were observed to have a fecal coliform count of 6 MPN/100ml and 40MPN/100ml for total coliform The samples obtained from samples obtained from points 1 and 4 had a bacterial load of 1.1x105CFU/ml while the samples obtained from point 14 had a bacterial load of 1.3 x104 CFU/ml The microbial diversity ascertained by the biochemical evaluation showed that the bacterial flora obtained from point 14 were Pseudomonas, Salmonella sp., E. coli and Enterobacter sp. The groundwater sources were tained by the anthropogenic activities in the Wamakko LGA as this have shown a shift in the microbiological qualities of the water samples. There is need for Sokoto State Government to look into the remote cause of the water pollution and come up with a risk-oriented strategies to stem these tides.

The effects of water content on mineralogical and drainage quality dynamics in weathering mine waste rock

Water content plays a critical yet ambivalent role in the physical and geochemical stability of mine tailings and waste rock, but its effects on individual chemical weathering reactions (dissolution and precipitation) and bulk water quality remain poorly understood. We experimented with synthetic waste rock to quantitatively reconcile modal and textural mineralogical parameters (mineral size, association, and liberation) with leachate quality at different water saturation levels (5–100%). Leachate pH consistently decreased from a 13-week average of 6.14 at 100% saturation to 5.37 at 5% saturation. Simultaneously, mineralogical analyses revealed a reduction in the size of carbonate phases over the course of weathering, decreasing from 200 µm to 145 µm as water saturation increased from 5% to 100%, which could be a contributing factor to more alkaline pH in samples with higher water saturation. Total concentrations of iron (Fe) and copper (Cu) in solution increased with lower moisture, with Cu concentrations increasing 24-fold in samples at 5% saturation compared to full saturation. In contrast, arsenic (As) concentration increased with higher moisture levels, which we attribute to reduced galvanic protection of As-bearing pyrite from oxidation. Multivariate statistical evaluation allowed us to uncover correlations between water chemistry and mineralogical data (i.e., sulfide associations or phase perimeters) and to explain chemical differences between samples, particularly those at 100% and 5% water saturation. Our findings underscore the importance of conducting quantitative mineralogical investigations on mine waste materials and considering their stored water content in the formulation of mine waste management strategies.

Effect of Antigonon leptopus extract in corn starch-glycerol based film as colourimetric indicator film for monitoring fish freshness

A colourimetric indicator can be used to test the freshness of fish in a rapid, straightforward and non-destructive manner. Anthocyanin, a natural dye found in Antigonon leptopus flowers, has a sensitive colour reactivity to a wide range of pH levels and can be made into colourimetric indicator films on a laboratory scale, making it a viable replacement for artificial dyes. The study's purpose was to see how the concentration of A. leptopus extract affected the colourimetric assessment of fish freshness. Ethanol was used to extract anthocyanin from A. leptopus. FTIR and pHrespond spectroscopies were used to characterise the extracts. Colourimetric indicator films were developed to assess fish freshness by incorporating A. leptopus extract into a corn starch-glycerol matrix via the solution casting method, with concentrations of 10%, 30% and 50%, respectively. The effect of A. leptopus extract on visual aspects, thickness, morphology, FTIR spectra, UV-Vis spectra and colour responses was analysed. Microbial analysis, TVB-N contents, firmness, and pH of the fish samples were analysed after storage. The colour of the original films became darker as the extracted content increased. There was no significant (p>0.05) effect of A. leptopus extract on film thickness. SEM micrographs revealed that the composite films had homogeneous and whitish granules on the surface and that increasing the A. leptopus extract concentration caused the films to become rougher. FTIR and UV-Vis spectroscopies showed successful binding between A. leptopus extracts and corn starch-glycerol film. With increasing pH, the colour change of the films exposed to pH = 3-11 solutions was no significant difference due to improper storage. An increase in the microbial population, TVB-N content and pH was observed over the storage period as a result of fish deterioration. Colour changes were also identified in the film which became darker. Overall, colourimetric indicator film with 50% A. leptopus extract was found to be the optimal formulation since it had the highest values in ∆E* during progressive spoilage of fish.

Magnetic surface-imprinted polymer microspheres coupled with HPLC-MS/MS for sensitive detection of amphetamine-type drugs in water

Magnetic surface imprinted polymer microspheres (Fe3O4@MIPs) were successfully synthesized via Pickering emulsion polymerization, utilizing N-Methylphenethylamine as a surrogate template for amphetamine-type drugs. Fe3O4@MIPs not only possessed excellent dispersibility and enough magnetic properties in aqueous solutions, but also displayed good selectivity towards six amphetamines, with an imprinting factor ranging from 1.8 to 2.6. The adsorption kinetics closely aligned with the pseudo-second-order model, and the adsorption efficiency exceeds 80 % for each amphetamine at equilibrium. Fe3O4@MIPs were then employed as the efficient adsorbents for the extraction of amphetamine drugs. Extraction parameters, including sample pH, the mass of adsorbent, and the type and volume of eluting solvent, were carefully optimized. In combination with the high performance liquid chromatography tandem triple quadrupole mass spectrometry (HPLC-MS/MS), a selective magnetic solid-phase extraction (MISPE) method utilizing Fe3O4@MIPs was developed for the detection of six amphetamines in water samples. The limits of detection and limits of quantitation were determined to be 5.2∼23 ng L−1 and 17∼77 ng L−1, respectively. Recoveries for the six target drugs from lake water and sewage samples fell within the range of 87.2∼110 %. Additionally, the MISPE-HPLC-MS/MS method exhibited excellent repeatability, with a precision below 8.5 % at two spiking levels. The prepared Fe3O4@MIPs possessed the advantages of high selectivity, straightforward preparation, facile separation and good reusability, and was highly suitable for the efficient extraction of amphetamine-type substances in complex environmental water.

Comprehensive study on physico-chemical soil analysis for optimizing paddy (Oryza sativa L.) cultivation in Kamrup (Metro) district of Assam, India

Rice being the staple food in Assam, its productivity should be increased for the availability of the common people. The main objective of this study is to compare the qualities of soil samples and to correlate the results with the production (per year) of paddy (Oryza sativa) from 3 different studied areas. The soil samples were collected during March-May, 2023. The oven dry method and drying and weighing method are used to determine bulk and particle densities respectively. The electrical conductivity and pH of the soil samples are determined using a benchtop conductivity meter and pH meter. Walkley-Black chromic acid wet oxidation method and methylene blue method are used to determine the organic carbon and cation exchange capacity (CEC) of soil samples respectively. Nitrogen, phosphorus, and potassium of the soil samples are estimated using the instrument Mridaparikshak. The moisture content, bulk density, particle density, soil porosity, cation exchange capacity (CEC), pH, electrical conductivity, nitrogen, P2O5, and K2O are observed in the range of 24.69 % to 39.42 %, 1.12 g cm-3 to 1.25 gcm-3, 1.83 gcm-3 to 1.99 g/cm-3, 33 to 43, 2.8 × 10-5mol dm-3to 11.7x10-5 mol dm-3, 7.4 to 8, 0.23 dS/m to 0.40 dS/m, 0.645% to 1.49%, 213.20 kg/ha - 235.14 kg/ha, 17.92 kg/ha - 20.44 kg/ha and 148.92 kg/ha -164.45 kg/ha respectively. The soil characterized by moisture content =27.52 %, bulk density=1.25 gcm-3, particle density =1.86 g cm-3, porosity =33%, cation exchange capacity =11.7 x 10-5 mol dm-3, pH {(1:5) at 210C} = 7.9, electrical conductivity = 0.40 dS/m, organic carbon =0.825 %, organic matter =1.42 %, N =235.14 kg/ha, P2O5 = 20.44 kg/ha and K2O =164.45 kg/ha showed good yield.

Polyether sulfone flat-sheet membrane impregnated with Mn-Al layered double hydroxide nanoparticles for green microfiltration of acrylamide in cocoa products.

A new polyether sulfone (PES) membrane modified with manganese-aluminum layered double hydroxide (Mn-Al LDH) was prepared and utilized in the membrane micro-solid phase extraction (M-µSPE) of acrylamide for the first time. The analyses were conducted using HPLC-UV. The extraction efficiency of the PES membrane was enhanced two-fold with the addition of LDH. The fabricated LDH@PES was characterized using ATR-FTIR, SEM, XRD, and nitrogen adsorption/desorption isotherms. The specific surface area, average pore diameter, thickness, cross-sectional channels, and LDH particle size of the LDH@PES membrane were determined. The extraction key factors including membrane composition, desorption conditions, sample pH, and salt concentration were studied. The method was validated by determining the limit of detection, the limit of quantification, linear range, r2, matrix effect, enrichment factor, and precision. Extraction recoveries ranged from 87.4 to 103.5% with RSD < 5.9%. Finally, the method's green features were assessed with the AGREE protocol. This is the first report on the application of LDH@PES for microfiltration/extraction of acrylamide in various chocolate and cocoa products.