Comparative analysis of the equilibrium, kinetics, and characterization of the mechanism of rapid adsorption of Congo red on nano-biosorbents based on agricultural waste in industrial effluents.

This study aims to remove Congo red dye from industrial effluent using economical agriculturally-based nano-biosorbents like magnetic orange peel, peanut shells, and tea waste. The nano-biosorbents were characterized by various analytical techniques like SEM, FT-IR, BET and XRD. The highest adsorption capacity was obtained under the following ideal conditions: pH = 6 (orange peel and peanut shells), pH = 3 (tea waste), and dosages of nano-biosorbents with varying timeframes of 50 min for tea waste and peanut shells and 30 min for orange peel. The study found that tea waste had the highest removal rate of 94% due to its high porosity and responsible functional groups, followed by peanut shells at 83% and orange peel at 68%. The Langmuir isotherm model was found to be the most suitable, with R2 values of 0.99 for tea waste, 0.92 for orange peel, and 0.71 for peanut shells. On the other hand, a pseudo-second-order kinetic model was very feasible, showing an R2 value of 0.99 for tea waste, 0.98 for peanut shells and 0.97 for orange peel. The significance of the current study lies in its practical application, enabling efficient waste management and water purification, thereby preserving a clean and safe environment.

Electrochemical sensing of B-complex vitamins: current challenges and future prospects with microfluidic integration.

Vitamins are crucial micronutrients found in limited quantities in food, living organisms, and soil. Since most vitamins are not produced within the human body, a lack of these essential nutrients can result in various physiological disorders. Analyzing vitamins typically involves costly, time-consuming methods, requiring skilled personnel, automated equipment, and dedicated laboratory setups. The pressing need is for the development of efficient, portable, and user-friendly detection techniques that are cost-effective, addressing the challenges associated with traditional analytical approaches. In recent years, electrochemical sensors and electrochemical microfluidic devices have garnered prominence owing to their remarkable sensitivity, quick analysis, cost-effectiveness, and facile fabrication procedures. Electrochemical sensing and microfluidics are two distinct fields that are often integrated to create powerful and versatile sensing devices. The connection between them leverages the advantages of both fields to create highly efficient, miniaturized, and portable analytical systems. This interdisciplinary approach has led to the development of innovative devices with broad applications in various scientific, medical, and environmental domains. This review begins by outlining the importance of vitamins in human nutrition and health and emphasizing the need for precise and reliable sensing techniques. Owing to the limited literature available on electrochemical detection of vitamin B complexes, this review offers an in-depth analysis of modern electrochemical sensing of water-soluble vitamins, focusing on B1, B2, B6, B9, and B12. The challenges faced by researchers are addressed, including selectivity, sensitivity, interference, matrix effects, and calibration, while also exploring promising prospects such as nanomaterial integration, miniaturization, microfluidics-based IoTs, and innovative sensor designs.

Activated carbon derived from Dodonaea Viscosa into beads of calcium-alginate for the sorption of methylene blue (MB): Kinetics, equilibrium and thermodynamics.

Dyes are valuable color compounds used in textile industries but at the same time their toxic and carcinogenic properties distract environmental system due to the chemical intricacy and multiplicity smearing them non-biodegradable. Therefore, the aim of present research rests in the use of cost effective, easily available and eco-friendly reformed novel biosorbents of Dodonaea Viscosa (DV). For this purpose AC-alginate beads were synthesized successfully through clogging AC derived from Dodonaea Viscosa (ACAB) into beads of calcium-alginate for removal of methylene blue (MB) from diluted solution. The external morphology (SEM, EDX) and functional groups (FT-IR) supported the favorable conditions for adsorption. The thermal properties have been evaluated using thermo-gravimetric study (TGA). After proper optimization like at pH 8, and biosorbent dose of 250 mg, temperature 350 K and time at 60 min the obtained adsorption capacity for DV leaves was set up to be 239 mg/g and for ACAB was 370 mg/g. By applying different adsorption isotherm models, the Freundlich was found to be best suited with highest R2 = 0.998 for DV and 0.995 for ACAB biosorbents. While the various kinetics models were also verified and data was well matched to Pseudo-second order kinetics model (R2 = 0.99 for DV and 0.99 for ACAB). Thermodynamics parameters enlightened that the adsorption process was endothermic (ΔH = 19,097 for ACAB and 10,899.6 J/mol for DV, ΔS = 89,087 for ACAB and 5.94 (J/mol for DV) and spontaneous in nature. The desorption study was satisfactory up to five number of absorption-desorption cycles for both the adsorbents particularly ACAB reflected an excellent percent removal (>90%). Consequently, the viability of DV can be used as a possible potential precursor for AC preparation besides cost effective adsorbent in the real sample treatment for dye removal.

Electrochemical oxidation of amoxicillin, ciprofloxacin and erythromycin in water: Effect of experimental factors on COD removal.

An alternative method of electrochemical oxidation was employed to degrade persistent compounds in the form of antibiotics using strong oxidizing agents such as hydroxyl ions. A 24 factorial design was employed to check the effect of four factors namely pH, current density, electrolysis time and electrolyte concentration set at their high (+) and low (-) levels on the antibiotics (amoxicillin, ciprofloxacin and erythromycin) degradation in water. The response was obtained in the form of COD (chemical oxygen demand) removal. A prediction model was developed to predict the values of COD removal. Later the main effect, contribution and interactions were studied with Design Expert Software 7.0. About 89.5% COD removal was obtained when pH and time were set at their high level and the other two factors at their low level. It was determined that the pH when set at high level (pH 9) had the most effect (24.68) and contribution (43.6) in the degradation process and hence the removal of COD. This technology of electrochemical oxidation can be employed in industries to efficiently remove pharmaceuticals, paints, dyes and other organic compounds.

Chemical profiling, in vitro and in vivo bioactivities of leaf extracts of Vitex neugundo.

The Vitex negeundo is a widely used medicinal plant which has not been fully investigated in the past. We assessed the in vivo hepatoprotective and in vitro antioxidant, antibacterial, cytotoxicity and antiproliferative study of leaf extracts of V. Neugundo. The chemically profiled using HPLC, three flavonoids were quantified and GC-MS analysis revealed the presence of two new compounds those were not reported earlier. The animal study was conducted on mice treated with CCl4 using methanolic and chloroform extracts (100, 200 and 300 mg/kg b.w), with silymarin as a positive control. Hepatoprotective effects were determined by analyzing blood for liver marker enzymes, direct bilirubins and hematological parameters (RBC, WBC and platelets). The methanolic extract (300 mg/kg b.w) has shown the stronger hepatoprotective effects against abnormalities produced by CCl4. The in vivo hepatoprotective effects correlated well with the in vitro antioxidant, cytotoxicity and antiproliferative activities and with high levels of flavonoids and other organic compounds analyzed from plant extracts. The leaf extracts of this plant could be good candidates for lead compound required for the development of antioxidant/anticancer drugs.

Phytochemical screening and bioactivity assessment of leaves and fruits extract of Carica papaya.

The consumption of fruits and vegetables has increased in recent years due to their health benefits as fruits and vegetables contain secondary metabolites, those has been reported to possess different pharmacological effects against many human ailments. In the current study antioxidants, antimicrobial and cytotoxic effects of leaves and fruit extracts of Carica papaya were evaluated. The antioxidant activities of plant extracts were carried out by using 2,2 -diphenyl-1- picrylhydrazyl. (DPPH), H2O2, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and reducing power assays and were compared with standards compounds (Ascorbic acid and Rutin). Antibacterial and antifungal activities of leaves and fruit extracts were assessed against four bacterial and fungal strains and also their minimum inhibitory concentration (MIC) values were calculated. Whereas for evaluation of cytotoxicity of plant extracts, brine shrimps cytotoxic assay was performed. Plant extracts were finally analyzed for phytochemicals by using UV/Visible spectrophotometer and High performance liquid chromatography (HPLC). Results indicates that plants extracts contained important compounds (phenols, flavonoids and other secondary metabolites) those have higher antioxidants and antimicrobial as well as lower proportion of MIC values. Whereas cytotoxic index of plant extracts were minor that specifies its appropriateness to use as a pharmaceutical materials probably be essential for drugs preparation. It is expected that such drugs could be lesser toxic and have lower cost as compared to drugs already available in market.

Cellulose-hydroxyapatite carbon electrode composite for trace plumbum ions detection in aqueous and palm oil mill effluent: Interference, optimization and validation studies.

Environmental monitoring is important to determine the extent of eco-system pollution and degradation so that effective remedial strategies can be formulated. In this study, an environmentally friendly and cost-effective sensor made up of novel carbon electrode modified with cellulose and hydroxyapatite was developed for the detection of trace lead ions in aqueous system and palm oil mill effluent. Zinc, cadmium, and copper with lead were simultaneously detected using this method. The electrode exhibited high tolerance towards twelve common metal ions and three model surface active substances - sodium dodecyl sulfate, Triton X-100, and cetyltrimethylammonium bromide. Under optimum conditions, the sensor detected lead ions in palm oil mill effluent in the concentration range of 10-50 µg/L with 0.11 ±â€¯0.37 µg/L limit of detection and 0.37 ±â€¯0.37 µg/L limit of quantification. The validation using tap water, blood serum and palm oil mill effluent samples and compared with Atomic Absorption Spectroscopy, suggested excellent sensitivity of the sensor to detect lead ions in simple and complex matrices. The cellulose produced based on "green" techniques from agro-lignocellulosic wastes, in combination with hydroxyapatite, were proven effective as components in the carbon electrode composite. It has great potential in both clinical and environmental use.

An empirical investigation of the determinants of CO2 emissions: evidence from Pakistan.

The aim of this paper is to examine the relationship between CO2 emissions and its possible determinants and their direction of causality for Pakistan over the period of 1972 to 2017. The survey of literature guides us that the most frequently discussed factors are real GDP per capita, energy consumption, urbanization, trade openness, and financial development. Testing of environmental Kuznets curve (EKC) hypothesis is the most common in environment literature so we also incorporated the real GDP per capita squared term in the model. Autoregressive distributed lag (ARDL) bound testing approach to cointegration with structural break and error correction method (ECM) are applied to the selected time series to investigate the long-run relationship between CO2 emissions and real GDP per capita, real GDP per capita squared term, energy consumption, urbanization, trade openness, and financial development. The empirical evidence confirms the cointegration among the variables and EKC holds for Pakistan support H1 of the study, which though contradictory to the previous studies conducted on Pakistan but all of previous work faces the exclusion bias and their findings were skewed. The findings also suggest that energy consumption and urbanization have a positive effect on CO2 emissions, supporting H2 and H3. However, H4 and H5 rejected as trade openness and financial development found positively significant. Moreover, bidirectional Granger causality was exists only between CO2 emissions and trade openness. The findings suggests that Pakistan need to settle the economic agenda of the nation through the resolution of economic controversies, energy mix need to tilt toward clean and renewable energy, and rural-urban migration need to manage for better air, water, and living.

Characterization of toxic metals in tobacco, tobacco smoke, and cigarette ash from selected imported and local brands in Pakistan.

In this study, concentrations of Cd, Ni, Pb, and Cr were determined in tobacco, tobacco smoke-condensate, and cigarette ash for selected brands used in Pakistan. Smoking apparatus was designed for metal extraction from cigarette smoke. Samples were digested through microwave digester and then analyzed by flame atomic absorption spectrophotometer (FAAS). Higher concentration of Ni was detected in imported brands than the counterparts in the local brands. Pb levels were however higher in local brands while significant concentration of Cd was observed in both brands. For Cr, the level in tobacco of local brands was higher than their emitted smoke, whereas imported brands showed higher level in smoke than in tobacco. The cigarette ash retained 65 to 75% of the metal and about 25 to 30% went into the body. While this study revealed the serious requirement to standardize the manufacturing of tobacco products, more importantly is the urgent need for stronger enforcements to put in place to alert the general population about the hazardous effects of cigarettes and the health risks associated with these toxic metals.

Evaluation of trace metals in tobacco of local and imported cigarette brands used in Pakistan by spectrophotometer through microwave digestion.

Uncontrolled exposure of active and passive smokers to trace metals causes increase in health risks. The primary objective of this study was to determine whether local and imported cigarette brands used in Pakistan, have elevated levels of metals or not. Six metals manganese (Mn), cobalt (Co), copper (Cu), cadmium (Cd), lead (Pb) and zinc (Zn) were determined in tobacco of twenty cigarette brands (local and imported) used in Pakistan by flame atomic absorption Spectrophotometry. To overcome contamination chances and for complete digestion of analytes a microwave digester was used. The analytical results showed highest concentration of Mn (84.78 microg/g dry weight), Cd (0.525 microg/g dry weight) and Zn (14.34 microg/g dry weight) metals in imported brands in relation to counterparts from the local brands. Certain elevated levels were observed for Co (3.344 microg/g dry weight), Pb (14.16 microg/g dry weight) and Cu (7.889 microg/g dry weight) metals in local brands. The inter-metal relationships in the tobacco of local and imported cigarette brands showed some integrated variation in the selected metal levels. In view of health risk associated with the above metals, there should be a strict quality control over monitoring of heavy metals during growing, processing and smoking of tobacco. Therefore, it is prudent to minimize exposure to toxic substances whenever possible because smoking and exposure to cigarette smoke is a confounder to be taken into account when carrying out epidemiological studies on human exposure to metals.