Sample pH Research Articles

A novel sample pretreatment of nanofiber-packed solid-phase extraction of aflatoxin B1, B2, G1 and G2 in foods and simultaneous determination with HPLC

A novel analytical method based on nanofiber-packed solid-phase extraction (PFSPE) combined with HPLC-FLD has been successfully developed and applied to determine aflatoxin B1, B2, G1, G2 in foods. In order to effectively adsorb analytes from complex food matrices, four types of nanofibers based on skeleton of polystyrene–polyvinyl pyrrolidone were prepared by electrospinning and applied as adsorbent to home-made solid-phase extraction device. The effects of type of nanofibers, pH of sample, type and concentration of salt ion, type of activation solvent, type and volume of eluent, amount of nanofibers, and extraction time on the adsorption/desorption were investigated and optimized. Under optimal conditions, the method showed satisfactory linear relationship, with limits of detection (LODs) of 0.07–0.17 ng g−1, intra-day and inter-day RSDs for spiked samples of 1.3–8.0 % and 1.9–5.8 %, and absolute recoveries in the range of 60.1–98.4 %. The results presented the great potential to be utilized to determine AFs in foodstuffs.

Integrated surface geochemical and seismic surveys for hydrocarbon exploration - A case study from southern Poland

Surface geochemical surveys were carried out in the Pawłosiów area in the eastern part of the Carpathian Foredeep. The research included an analysis of the molecular composition of soil gas samples as well as measurements of the calcite content, magnetic susceptibility and pH of soil samples. The results obtained were integrated with a geological-seismic model. Changes in the concentrations of total alkanes C2–C5 in relation to changes in indirect geochemical indicators showed “compensatory” character. This means that in places where alkane concentrations were increasing, negative anomalies of magnetic susceptibility and a decrease in pH values were observed. It may be related to the intensity of the oxidation processes or reduction of the magnetic minerals in, as well as the reduced permeability of, the Miocene layers in the zones analysed. Moreover, the complex geochemical-geophysical interpretation showed a zone of anomalous values of the total C2–C5 alkanes in the Pawłosiów area, which is suitable for prospecting. The research performed proved that a thorough analysis of the seismic record allowing subtle DHI anomalies appearing within the Miocene formations to be located, combined with the use of direct and indirect geochemical indicators, can help in identifying an area in terms of hydrocarbon potential. This applies in particular to this type of foreland basin, within which geological formations lie flat, and positive structures (anticlines) are hardly visible in seismic sections. In this type of structure, hydrocarbons can be accumulated in traps of a hybrid character (conventional and unconventional). The extensive zone of geochemical and geophysical anomalies found in the area of Pawłosiów may indicate the presence of this type of hydrocarbon accumulation.Comprehensive research, including direct and indirect geochemical methods in combination with a seismic survey, allows for a better assessment of the hydrocarbon potential of the studied area.

A Study on Pharmacological Evaluation of Diuretic Activity of Tinospora cordifolia Stem Ethanolic Extract

This study aimed to assess the diuretic effects of Tinospora cordifolia stem ethanolic extract in Swiss Albino Rats. The administration of the higher dose (200 mg/kg) of the ethanolic extract derived from the stem part of Tinospora cordifolia resulted in a significant increase in diuresis during the 6th hour, with a measured output of 1.93 + 1.21ml, compared to the control group (0.38+ 0.12 ml). This effect was also compared to the reference standard, furosemide, which produced an output of 2.45 + 1.12ml (p < 0.05). Similarly, the higher dose (400 mg/kg) of Tinospora cordifolia stem extract demonstrated significant diuretic activity (2.70 + 1.15 ml) compared to the control group (1.14 + 0.09 ml) (p < 0.05). The increase in urine output was statistically significant (p < 0.01). The study also analysed the impact of furosemide (10 mg/kg) and Tinospora cordifolia extracts at doses of 200 mg/kg and 400 mg/kg on the excretion of electrolytes (Na+ and K+) in the 6-hour urine samples. The pH of the urine samples following treatment with Tinospora cordifolia stem extract at doses of 200 mg/kg and 400 mg/kg was measured to be 5.48 and 6.79, respectively. The results obtained in this study provide a quantitative basis for explaining the diuretic activity of Tinospora cordifolia. The extract displayed notable diuretic activity, thus supporting its traditional use as a diuretic in ethno-pharmacology. Further investigations, including phytochemical and pharmacodynamic studies, are necessary to identify the active constituents responsible for this activity and to understand the exact mechanism of the diuretic effect exhibited by the aqueous extract of Tinospora cordifolia.

The Influence of an Isocyanate Structure on a Polyurethane Delivery System for 2'-Deoxycytidine-5'-monophosphate.

The delivery of nucleosides represents an interesting research trend in recent years due to their application in various viral infections. The main aims of this study were to develop and to characterize polyurethane particles that are intended to be used for the transport of nucleosides. Three samples have been prepared using aliphatic diisocyanates, a mixture of polyethylene glycol, polycaprolactone, and diols, respectively. The samples were characterized through refractivity measurements, drug loading efficacy, release and penetration rate investigations, FTIR and Raman spectroscopy, thermal analyses, Zetasizer, SEM, HDFa cells viability, and irritation tests on mice skin. The results indicate the obtaining of particles with sizes between 132 and 190 nm, positive Zeta potential values (28.3-31.5 mV), and a refractivity index around 1.60. A good thermal stability was found, and SEM images show a medium tendency to agglomerate. The samples' color, pH, and electrical conductivity have changed only to a small extent over time, and the evaluations indicate an almost 70% encapsulation efficacy, a prolonged release, and that around 70% of particles have penetrated an artificial membrane in the first 24 h. The synthesized products should be tested in further clinical trials, and the current tests on cell cultures and mice skin revealed no side effects.

Contributions of heavy metals on Underground Water quality of Dumpsite in Rukpokwu, Rivers State, Nigeria

Waste dump sites have constituted major challenge to ground water quality in neighbouring environment. This study was carried out to assess the contributions of heavy metals in groundwater from abandoned Rukpokwu dumpsite after a 6-month use. Samples were collected and immediately transferred to the laboratory for standard analysis. The values of parameters of water samples pH ranged from 7.02 – 6.98. were quite below the WHO and NSDWQ limits. Conductivity ranged from 42.73- 19.91, TDS ranged from 10.76 -44.56, Turbidity ranged from 3.87 – 20.02, BOD ranged from 0.92 – 2.90, COD ranged from 1.74 – 3.21, Fe., ranged from 0.02 – 1.13, Zn ranged from 0.00 – 0.19, Cu ranged from 0.00 – 0.14,Pb, Cd and Cr were not detected in all the water samples. This might be that the contaminants could not migrate to the water table or aquifer within the period of use and study of the dumpsite.

Assessing the air pollution tolerance index (APTI) of trees in residential and roadside sites of Lahore, Pakistan

Industrialization and extensive use of automobiles cause air pollution which indicates the inability of trees plants due to changes in their biochemical and physiological processes for absorbing the air pollutants. Air Pollution Tolerance Index (APTI) is an important indicator for determining the ability of trees plants for their efficient ability for controlling air pollution. To estimate it and its effects a comparitive study of the air pollution tolerance index was examined in 14 species of plants between residential areas (University of the Punjab) and roadside areas (orange train line). To calculate the APTI value, four physiological and biochemical parameters—ascorbic acid, relative water content (RWC), pH, and chlorophyll concentration of leaf samples—were integrated. Present study results reveal that the plant tolerance against pollution is site specific, and that integrating a number of biochemical parameters give more accurate results as compared to single. Results show that Alstonia scholaris show maximum and Magnifera indica show minimum APTI values in residential areas while Magnifera indica shows maximum and Bougainvillea glabra shows minimum APTI value in roadside areas. Present study results show that plants with higher APTI values are tolerant of pollution, whereas those with lower APTI values are susceptible to it. Thus Plants with more APTI values are tolerant and use as a sink to control pollution in urban and industrial sites.

Detection and removal of cadmium ion by a neoteric polyethylenimine carbon dots @ lanthanum orthoferrite nanocomposite

In this study, a fluorescent polyethylenimine carbon dots (PEI-CDs) and an adsorbent lanthanum orthoferrite (LaFeO3) are composited as PEI-CDs/LaFeO3 (LFPC), concerning simultaneous detection and removal of cadmium (Cd) ions in the aqueous medium. The fluorescent “Off-On” mechanism is used in detecting cadmium ions and the removal of Cd ions is achieved by the adsorption method. Metal ions selectivity, optimization of the sensor with pH and time, the limit of detection, batch experiments (effect on adsorption by varying pH, initial concentration of metal ions, and adsorbent dosage), and adsorption isotherm studies are carried out in a standardized methodology for effective detection and removal of cadmium ions. The sample's pH is a significant parameter for both detection and removal, here pH 6 is an optimum condition to attain high fluorescent sensitivity and adsorption efficiency. Real sample analysis is performed to check the material's practicability. The synthesized material is characterized by X-ray diffraction, UV‐Vis spectroscopy, photoluminescence spectroscopy, Fourier transform infrared analysis, scanning electron microscopy, high-resolution transmission electron microscopy and energy dispersive X-ray analysis. The lifetime of a fluorophore and zeta potential measurements support the mechanism behind the sensing and the removal of cadmium ions.

Application of the UV-C assisted persulphate/peroxymonosulphate process for the mineralization of organic substances in drinking water

The aim of this study was to evaluate the high oxidation potential of hydroxyl and sulphate radicals generated by UV-C assisted persulphate (PS) and peroxymonosulphate (PMS) processes in natural water. The effects of initial oxidant concentration on degradation processes were investigated using TOC, PS, pH, and UV254 measurements in samples taken at specific time intervals. The particle size distribution profiles were also determined for the raw water and effluent samples from the PS/UV-C and PMS/UV-C. Accordingly, the final removal rates were 19%, 40%, and 55% for PS/UV-C doses of 0.2 mM, 0.5 mM, and 1.0 mM, respectively, while the TOC removal was 20%, 35%, and 64% for 0.2 mM, 0.5 mM, and 1.0 mM PMS/UV-C, respectively. The results showed that the rate constants of TOC removal followed first-order kinetics for both PS and PMS. The general assessment of energy consumption during the PS/UV-C and PMS/UV-C processes showed that the time required for the same amount of TOC removal decreased as the initial PS/PMS concentration increased, so that the energy required decreased in relation to volume and mass. Overall, the obtained results were used for a comparative analysis of the oxidation process, and the recommended process was evaluated with samples taken from the effluent of each unit of the drinking water treatment plant to determine the correct location for the treatment process. The results showed that the PS/UV-C process should be designed after filtration, rather than after sedimentation, and the end of the treatment plant.

Environmental impacts of 5-year plastic waste deposition on municipal waste landfills: A follow-up study

Depositing plastic waste has long been a prevalent method of utilization, persisting today. Plastic waste within municipal waste landfills (MWL) undergoes diverse (bio-)degradation processes, which may be a potential source of chemicals and microorganisms harmful to the environment and human health. Soil and air samples were collected from modern MWL to identify environmental contamination caused by 5 years of plastic (bio-)degradation. The pH of soil samples was higher than in the reference area (RA), which was possibly caused by alterations in soil anionic composition detected with ion chromatography. The presence of plastic additives with a toxic potential was detected in soil samples by gas chromatography coupled with tandem mass spectrometry (GC–MS/MS). With the use of thermal desorption and GC – MS, hazardous substances (phthalic anhydride, phenylmaleic anhydride, ethylbenzene, xylene) with a known impact on the human endocrine system were also detected. The number of microorganisms, both fungi, and bacteria, was highly increased in soil and air in the MWL as compared to the RA. The soil collected in the MWL area appeared to be phytotoxic, and inhibited seed germination (Phytotoxkit FTM bioassay), while acute toxicity Microtox® bioassay showed a hormetic effect towards Aliivibrio fischeri. Obtained results exhibited massive soil and air contamination, with both chemical substances and microorganisms while plastic waste undergoes (bio-)degradation. It may contribute to serious environmental contamination and pose a threat to human health.

Novel capsule phase microextraction - Gas chromatography - Mass spectrometry for analysis of pheniramine in a case of its fatal intoxication

In forensic toxicology, the extraction and purification of analytes from complex biological matrices heavily rely on the effectiveness of sample preparation methods. However, existing methods often face inherent challenges such as interfering substances and limited sample quantities, which can compromise the accuracy and efficiency of toxicological analyses. In the present work, for the first time, capsule phase microextraction (CPME) was implemented in forensic toxicology casework for the straightforward, affordable and sustainable extraction of the pheniramine (PHN) drug from human autopsy samples (whole blood and liver) and determined by GC-MS. A systematic investigation was conducted to optimize the extraction efficiency of CPME by examining and optimizing significant variables such as pH and volume of sample, adsorption time, desorption time and volume. The optimized method demonstrated linearity, covering a range of 0.1–10 μg mL−1 for blood samples and 0.1–10 μg g−1 for liver samples. The limit of quantification (LOQ) of the method for PHN in blood and liver samples was determined to be 0.063 μg mL−1 and 0.076 μg g−1, respectively. Repeatability and reproducibility of the method were less than 3.2% and 9.2%, respectively. The method demonstrated accuracy and recovery within the ranges of 94%–101.3%, and 67.4%–82%, respectively. The method was applied for analysis of autopsy samples from a case of fatal PHN intoxication and results were compared to those obtained using the conventional solid-phase extraction (SPE) method. Further, the competence of the proposed method has been judged by White Analytical Chemistry (WAC) RGB12 algorithm. CPME-GC-MS method demonstrates notable performance and significant stride in the domain of postmortem toxicology sample preparation. It is superior to traditional methods in several ways such as simpler, more sustainable, affordable and overcome the challenges of interfering substances and limited sample quantity.

Photodegradation of MC-LR using a novel Au-decorated Ni metal-organic framework (Au/Ni-MOF)

Microcystins (MCs) are toxins produced by cyanobacteria commonly found in harmful algal blooms (HAB) occurring in many surface waters. Conventional methods for removing MC-LR such as membrane filtration and activated carbon are only phase change removal methods and are often expensive in operation and maintenance. It is urgent to develop a rapid, easy-to-use, and cost-effective method for the degradation of MC-LR. In this study, a novel Au-decorated Ni-metal-organic framework (Au/Ni-MOF) was newly developed on a hydrophilic carbon fiber paper (2 cm × 2 cm) using an air spraying method. The Au/Ni-MOF was then applied for the photodegradation of MC-LR in water under UV–Vis. The addition of Au onto the surface of the Ni-MOF resulted in a nearly fivefold enhancement in the reaction rate coefficient (k), reaching a value of 0.0599 min−1 for the photodegradation of MC-LR (initial concentration of 20 ppb). It was found that 94.2% of MC-LR removal was attributed to photodegradation, with the remaining 5.8% from adsorption. The rate coefficient of 20 ppb of MC-LR in the surface water sample (pH 6.0) was 0.06 min−1 likely due to the presence of other contaminates including scavenger agents within the sample which inhibits the degradation reaction of the MC-LR. Overall, this study demonstrated the potential for the novel Au/Ni-MOF to effectively reduce the concentration of the MC-LR toxin in the contaminated water.

Sonochemical synthesis of cobalt (II) metal–organic framework (TMU‐10)/polypyrrole nanocomposites with high adsorption capacity for dye removal from water

AbstractIn this study, Tarbiat Modares University‐10/poly pyrrole (TMU‐10/PPy), a water‐stable metal–organic framework/polymer composite, was successfully fabricated and applied as adsorbent for removal of methyl red from contaminated water. The pyrrole obtained novel‐structured TMU‐10@PPy composite showed high efficiency in removing the methyl red. Several variables affecting the adsorption efficiency of methyl red, that is, pH, amount of adsorbent, contact times, and the salt additive, were investigated and optimized. The best working conditions were as follows: sample pH, 5; amount of sorbent, 4 mg; contact time, 9 min; salt additive, 2% (wt/vol). The maximum adsorption capacity of TMU‐10@PPy toward methyl red was 101.01 mg/g. The adsorption kinetics and isotherms of TMU‐10@PPy were consistent with a pseudo‐second‐order kinetic model and the Langmuir isotherm model. It was found that TMU‐10@PPy exhibited excellent reusability and had the potential for treating dye‐polluted wastewaters.

Influence of complex coacervation on the structure and texture of plant-based protein-polysaccharide composites

Plant-based foods that mimic the sensory attributes of meat and seafood are being developed to address environmental, animal welfare, and health concerns linked to livestock production and processing. However, it has been challenging to accurately replicate the structure, texture, and functionality of many animal-based products using plant-derived ingredients. Soft matter physics principles are therefore being employed to address this issue. In this study, a combination of coacervation and thermal gelation of gellan gum-potato protein mixtures was used to create biopolymer composites with meat-like textures. One of the main aims of the study was determine whether the structural organization and rheology of biopolymer composites could be controlled by modulating the electrostatic interactions between the potato protein and gellan gum using pH adjustments. The ζ-potential of the complexes was positive at pH 4, near zero at pH 5, and negative at pH 6, which was mainly attributed to the reduction in the positive charge on the potato proteins when the pH was raised towards their isoelectric point. In contrast, the charge on the gellan gum remained strongly negative at all pH values. Large clumps were formed at pH 4 due to strong electrostatic attraction between the proteins and polysaccharides. However, fibril structures were formed after heating at pH 6, which was mainly attributed to the formation of coacervates. Interestingly, a substantial quantity of air bubbles was generated within the biopolymer composites during the blending of the protein and polysaccharide mixtures at pH 4, which influenced the structure and rheology of the heat-set composite gels. In contrast, fewer air bubbles were generated during blending at pH 6, which was attributed to differences in the ability of the complexes to adsorb to air-water interfaces and stabilize air bubbles. The electrostatic complexation of the proteins and polysaccharides also influenced the dynamic shear modulus of the composite gels during heating and cooling, with the final shear modulus depending on sample pH: pH 4 > pH 6 > pH 5. Overall, our findings highlight the potential of using coacervation combined with heating to create meat analogs with different fibrous structures and gel strengths, which may facilitate the design of plant-based foods with desirable textural attributes.

Simultaneous determination of various heavy metal and arsenic ions in seafood using functionalized fibrous silica (KCC-1) coated stir bar sorptive extraction prior to inductively coupled plasma mass spectrometry

Heavy metal ions (HMIs) and arsenic ion with high bioavailability and toxicity in seafood pose a serious threat to human health by food chain. Herein, the functionalized fibrous silica (KCC-1) nanoparticles bearing thiol (-SH) and amine (-NH2) groups respectively were synthesized, characterized, and coated on stir bar sorptive extraction (SBSE) of trace cadmium (Cd), mercury (Hg), lead (Pb), copper (Cu), and arsenic (As) ions simultaneously in seafood prior to inductively coupled plasma mass spectrometry (ICP-MS). The optimal SBSE variables, such as sample pH (3–7), elution composition (1 M HNO3 and 0–4% (m/v) thiourea), and sample volume (5–25 mL), were optimized. The optimal sample pH (6), elution composition (1 M HNO3 and 2% (m/v) thiourea), and sample volume (20 mL), were obtained. The performance of KCC-1-SH SBSE method was superior to the KCC-1-NH2 SBSE method in terms of linearity (0.9981–0.9992), limit of detection (LOD, <0.08 μg kg−1), limit of quantification (LOQ, <0.60 μg kg−1), recovery (85.6–106.6%), and repeatability and reusability (no apparent loss in extraction efficiency after 18 times). The maximum residual limits of Cd, Hg, Pb, Cu, and As (V) in mussel, shellfish, and shrimp were all below 1, 1, 1.5, 20, and 76 mg kg−1, respectively. The results demonstrated that the method has a great potential for the daily monitoring of trace HMIs in these seafood products.

Variability of pH and EC of Selected Rice Cultivated Soils of Sri Lanka

Soil pH and electrical conductivity (EC) are two major chemical properties affecting nutrient availability and rice grain yield. Therefore, this study was conducted to investigate the variation of pH and EC in the topsoil layer (0-15 cm) of rice fields as affected by major water source used for rice cultivation, rice-based cropping system adopted and rice growing soil orders in different agro-climatic zones (ACZs) in Sri Lanka. A total of 998 soil samples were collected from lowland rice fields. Both pH and EC were measured in 1:5 soil: water extracts. The pH of soil samples was in the range of 3.0-7.7 with a mean value of 5.0. Moreover, 75% of the soil samples had pH values below the optimum range for rice cultivation (5.5-7.0). Values of pH observed in Dry Zone soils were higher (5.2) than those in Wet Zone (4.4). Soil EC values ranged between 1.0 - 3,100 μScm−1 with a mean value of 148.5 μScm−1. Soil EC was similar among climatic zones (P&gt;0.05). Upcountry Intermediate zone recorded the highest soil EC than that in other ACZs (P&lt;0.05). Moreover, 73%, 22%, 3%, 2% and 0.1% of soil samples recorded EC values in the ranges of less than 150 (non-saline), 150-400 (slightly saline), 400-800 (moderately saline), 800-2000 (highly saline) and more than 2000 (very highly saline) μScm−1, respectively. Considering micro (e.g. paddy track) and macro (e.g. ACZ) scale spatial heterogeneity in soil pH and EC, appropriate site-specific strategies need to be adopted to improve soil pH and EC to suit sustainable rice crop production.

PEMANFAATAN SABUT KELAPA MELALUI METODE SLOW SAND FILTRATION UNTUK MEMENUHI KEBUTUHAN AIR BERSIH DI DESA TALANG TINGGI SELUMA

The sources of clean water is very important for everyone to support their life needs. However, Talang Tinggi Village, Seluma Regency has poor water supply conditions, indicated by the physical condition of the water which smells, the color is brown, and has sediment. This condition is getting worse because the source of water will be mixed with soil and mud. Talang Tinggi village does not have PDAM access yet, so the need for clean water only relies on natural water sources, swamp water and well water. This community service aims to overcome the problem of water resources in Talang Tinggi Village, Seluma Regency, Bengkulu Province by utilizing coconut fiber waste, as a filter media in the Slow Sand Filtration method. The results of the activity showed that there was a very significant improvement in water quality. The water that was cloudy and smelled becomes clearer and odorless. The value of acidity (pH) of the water sample also increased from 6.05-7.38 to 6.5-9.0. These results indicate that coconut fiber, which has been considered as waste, can be used to an effective filter for cleaning water.

The use of fermented minced fish with probiotics in the recipe composition of dry-cured sausages

The paper analyzes the effect of using fermented minced fish (FMF) with the L. plantarum probiotic in the formulation of dry-cured sausages on the quality characteristics of the finished product in comparison with sausages based on unprocessed minced fish. The microbiological, physico-chemical, structural-mechanical and organoleptic properties of the product have been evaluated. The results have shown that dry-cured sausage samples with FMF had a higher content of probiotics (2,5×108 CFU/g) compared to the control sample (6,3×106 CFU/g), which allows a person to fully meet the daily requirement in probiotics with just through the use of 40 g of such a product. The use of FMF in the dry-cured fish sausages provides a safe pH value (5.21) and significant increase in total acidity (1.39 %) compared to the control sample (pH – 6.80 and total acidity – 0.45 %). It has been established that using FMF in the technology of dry-cured fish sausages can reduce the time of their manufacture by increasing the average rate of dehydration of the product. It has been determined that samples of dry-cured sausages with FMF have higher values of hardness and cutting force. A comprehensive assessment of the quality of sausages with FMF has shown good results – 76.85 % of the maximum possible level. Thus, the possibility of using FMF with L. plantarum in the manufacture of dry-cured sausages has been determined. The proposed method makes it possible to obtain a product with a high protein content (32.31 %), enriched with L. plantarum probiotics, having a low pH value and a peculiar sour-milk taste and aroma. Based on the results of the study, normative and technical documentation for this type of product has been developed and approved.

B-166 Effect of Urine Adulteration on Quantifying both Delta 8- and Delta 9-carboxy tetrahydrocannabinol using a New UPLC-tandem Mass Spectrometry Method

Abstract Background The legality and use of marijuana is a controversial topic. With increased prevalence of usage, cannabis detection for legal, medical, and workforce drug testing is on the rise. LC-MS/MS quantification of delta 9-carboxy tetrahydrocannabinol (delta 9-THC-COOH) in urine is accepted as the standard to detect marijuana use. One challenge faced by testing laboratories has been identifying adulterated samples. Many products/reagents can be used to manipulate the urine to avoid positive drug testing results. In this study, we developed a dilute-and-shoot strategy to separate and quantify both the delta 8- and 9-THC-COOH in urine samples and tested the effects of adulteration using a combination of nitrite and/or acids which can be used to mask cannabinoid use. Methods Five authentic delta 8- and 9-THC-COOH positive specimens, and one spiked sample were treated with strong acids (1N HCL or 10% TCA), 500 µg/mL nitrite, or a combination. After hydrolysis with sodium hydroxide, the analytes were quantified using a 6495 Mass Spectrometer coupled to a StreamSelect LC system (Agilent). LC separation was performed with a CORTECS T3 column utilizing a shallow gradient. In addition, twelve urine specimens with varying concentrations of delta 8- and 9-THC-COOH were treated with nitrite and screened using a delta 9-THC-COOH immunoassay on the Roche Cobas C501 and analyzed by LC-MS/MS. Results Nitrite did not change the physical appearance or the pH of the urine samples. Strong acid treatment also did not alter the appearance but did drop the urine pH ≤2. Pre-treated specimens with 1N HCL, 10% TCA, or 500 µg/mL of nitrite did not affect the delta 8- and 9-THC-COOH concentrations up to 6 days (refrigerated); however, specimens treated with strong acid combined with 500 µg/mL of nitrite for 30 min made both analytes undetectable. Additional experiments confirmed that 0.5 and 1 mol/L of nitrite lowered the concentration of all analytes, including internal standard, to undetectable levels in 48 h. Twelve additional specimens were collected, 3 with delta 8-THC-COOH, 3 with delta 9-THC-COOH, and 6 with both. All 12 samples screened positive using the Roche immunoassay and were quantified using the LC-MS/MS method. After treatment with 0.5 mol/L of nitrite, 10 of the 12 samples were negative using the immunoassay, but 2 samples remained positive. However, all nitrite treated specimens were negative (&amp;lt;LLOQ) using the LC-MS/MS method and the internal standard was eliminated. Later experiments confirmed that the delta 8- and 9-THC-COOH could be eliminated with as little as 0.1 mol/L nitrite for 30 min. Conclusion The unique dilute-and-shoot method can separate and quantify delta 8- and 9-THC-COOH. In addition, high concentrations of nitrite were shown to degrade both analytes along with the isotopically labeled internal standard. As a result, labs can distinguish true negative delta 8- and 9-THC-COOH (no analyte peaks) from nitrite adulterated specimens since the adulterated samples have no peaks for both the analytes and internal standard. A limitation of the study is that only sodium nitrite was tested. Other adulterants, such as potassium nitrite, pyridinium chlorochromate, peroxide etc. require further investigation.

Deacidification and consolidation of brittle book paper using bacterial cellulose composite with zinc oxide nanoparticles

Paper, commonly used as an information carrier, can become acidified and brittle over time. In this study, 0.3 % bacterial cellulose (BC) composite with 1.0% zinc oxide (ZnO) nanoparticles was prepared and used to coat brittle book paper for deacidification and consolidation. The BC/ZnO nanocomposite was characterized using zeta potential, micro morphology, elemental mapping, X-ray photoelectron spectra, Fourier transform infrared, and thermogravimetric analyses. The results indicated that the composite exhibited good stability. ZnO nanoparticles were bonded to the hydroxyl groups on BC, enhancing the thermal stability of BC. The composite was uniformly sprayed on the paper surface, and the mechanical properties, color difference, readability, pH, and micromorphology of the paper samples were examined before and after the treatment. The BC/ZnO nanocomposite exhibited good deacidification and consolidation effects on paper samples with low impact on the original paper appearance. Moreover, the BC/ZnO nanocomposite showed a good inhibitory effect on fungi growth on paper.

Differential Effects of Organic Inputs on Soil Fertility and Growth of Tea Plants

The objective of the experiment was to evaluate how newly planted biclonal Tocklai stock tea varieties (TS 462, TS 463, TS 520, and TS 589) respond to compost in a series of treatment including control (without application), cow dung, vermicompost, municipal solid waste compost, and homemade kitchen waste compost applications. A total of 20 tea plants (5 plants of each tea variety) were planted in plastic buckets of equal size (16 litres). 300 gm. of compost was applied to each plant continuously at an interval of 25 to 30 days for the initial six months, and then compost application was discontinued for the next six months. Data were collected before, during, and after compost application. The highest growth in plant height (11cm to 51 cm), number of leaves (33 to 95), and number of branches (8 to 15) were recorded in the tea plants of the TS 463 variety. The pH of soil samples was found in the range of 4.72 to 6.61. The pH level of the acidic soil was slightly increased by the compost application. The average SOM% ranged from 6.88% to 11.94%, and it was found that a good SOM% was supportive of the good growth of the tea crop. N% was found between 0.85% and 0.217%, and P levels were found between 18 ppm and 50 ppm. The suitable N% and P levels affect plant growth most significantly in terms of the number of leaves and the number of stems. SOM% was found to be highest in vermicompost-treated soil, N% and P levels were optimal in home-made kitchen waste compost, and K levels were highest in cow dung-treated soil. Therefore, it can be concluded that an integrated compost application can be recommended for ideal growth and good plant health status for sustainable tea production.