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Conductive hydrogels have garnered significant attention in the realm of flexible electronic strain transducers (FESTs). However, the development of such FEST hydrogels has been hindered by weak mechanical performance and low conductivity, sensitivity, and stability. In this study, we introduce a novel FEST hydrogel with a wrinkled surface possessing a unique ability to differentiate between different spoken and written languages. Our approach involved fabricating a robust, tough, and ionic conductive hydrogel with a wrinkled texture through a simple strategy utilizing the hydrophobic initiator benzophenone (BP). BP was incorporated into hydrophobically cross-linked hydrogels composed of hydrophobic lauryl methacrylate (LMA), acrylamide (Amm), and the cationic monomer 2-(dimethylamino) ethyl acrylate methochloride (DMAEAMC), reinforced with trimesic acid (TMA). Pluronic 123 (P123) served as a source of micelles, dynamically connecting polymer chains and facilitating the diffusion of BP to produce wrinkled textured hydrogels. Furthermore, LiCl salt induced ionic conductivity (0.18 S/m), while the synergistic effect of TMA enhanced the mechanical performance through electrostatic interactions with DMAEAMC chains. The combination of hydrophobic and electrostatic interactions enabled the hydrogels to stretch up to 1611% with high conductivity, remarkable sensitivity (GF = 4.98 at 500%), and a wide strain range (0.1 to 500%). These hydrogels are valuable candidates for integration into epidermal FEST devices. Moreover, the epidermal FEST has the capability to monitor various large joint movements as well as different physiological activities. Additionally, FEST can identify different spoken and written languages, including English, Urdu, and Pashto, and can respond to other handwriting styles such as alphabets, numbers, and signatures. This approach provides a promising roadmap for engineering wrinkled texture hydrogels for diverse applications, especially in the fields of flexible sensors, electronic skin, and biomedical devices.

Emergency Resuscitative Thoracotomy (ERT) is a lifesaving procedure in selected patients. Outcome mostly in blunt trauma is believed to be poor. The primary aim of this study was to determine the predictors of postoperative mortality following ERT. We retrospectively reviewed 34 patients ≥ 18 years who underwent ERT at San Camillo—Forlanini Hospital (Rome, Italy) between January 2009 and December 2022 with traumatic arrest for blunt or penetrating injuries. Of 34 ERT, 28 (82.4%) were for blunt trauma and 6 (17.6%) were for penetrating trauma. Injury Severity Score (p-value 0.014), positive E-FAST (p-value 0.023), Systolic Blood Pressure (p-value 0.001), lactate arterial blood (p-value 0.012), pH arterial blood (p-value 0.007), and bicarbonate arterial blood (p-value < 0.001) were significantly associated with postoperative mortality in a univariate model. After adjustment, the only independent predictor of postoperative mortality was Injury Severity Score (p-value 0.048). Our experience suggests that ERT is a technique that should be utilized for patients with critical penetrating injuries and blunt trauma in patients in extremis. Our study highlights as negative prognostic factors high values of ISS and lactate arterial blood, a positive E-FAST, and low values of Systolic Blood Pressure, pH arterial blood and bicarbonate arterial blood.

Accurate and rapid detection of antibiotics is critical for protecting human health and the environment. To this end, we report a novel electrochemical sensor for the simultaneous detection of Levofloxacin (LFX) and Tryptophan (TRP) in dairy samples. Outstanding electrocatalytic activity for the oxidation of LFX and TRP is exhibited by the Activated Nanodiamond (AND) and Ti3AlC2max phase (Ti3AlC2max) nanocomposite-modified glassy carbon electrode (Ti3AlC2maxAND/GCE) featured in our sensor. High selectivity and sensitivity are achieved by the sensor, with limits of detection (LOD) of 20.47 nM and 0.309 μM for LFX and TRP, respectively. Moreover, strong anti-parasite capacity is demonstrated by the developed sensor, making it an excellent candidate for the establishment of a reliable sensing platform for antibiotic detection. Findings suggest that this novel sensor could serve as a valuable tool for monitoring the content of LFX and TRP in dairy samples and enhancing the safety of these products.

ABSTRACTIntroductionThe government of the Kingdom of Saudi Arabia (KSA) has developed a well-defined strategy to restructure the health sector and operate on value-based principles. Biosimilars are a viable option for increasing accessibility while lowering health-care costs.Areas coveredWe describe the current and future biosimilar landscape in KSA. We discuss the growth of the biosimilar market, the regulatory approval process, biosimilar adoption, and the potential impact on health-care systems and patient outcomes.Expert opinionThe biosimilar market in KSA is expanding and expected to continue this trajectory in the coming decade. The growth of the market is influenced by the KSA health transformation initiative, the well-defined regulatory framework for biosimilars set by the Saudi Food and Drug Authority (SFDA), and the adoption of biosimilars by health-care providers. Overall, the biosimilar regulation is evolving and the future of biosimilars looks promising in KSA. Biosimilars offer a more cost-effective alternative, which can help to expand access to more treatment options for patients and contribute to cost saving for the health-care system.

Wearable sensors made of flexible and stretchable hydrogels have garnered significant attention. However, their use has been limited by poor mechanical performance, such as poor toughness, poor self-recovery, and a large response–recovery time. To overcome these limitations, we have developed a novel cross-linking agent-based hydrogel with high stretchability, high toughness, antifatigue properties, and good conductivity. These hydrogels were developed by introducing l-glutamic acid (LGA) into hydrophobically cross-linked polyacrylamide (PAmm) chains. In this system, LGA dynamically cross-linked the micelle–micelle and micelle–polymer chains and greatly regulates the mechanical properties of the hydrogels. The noncovalent synergistic interactions that came with the insertion of LGA enable the hydrogels to achieve high stretchability and high stress values, with fast self-recovery and antifatigue behaviors without the help of foreign stimuli. Additionally, LGA-based hydrogels can function as durable and highly sensitive strain sensors for detecting various mechanical deformations with a fast response–recovery time and high gauge factor value. As a result, the hydrogels have the capability to be designed as wearable strain sensors that are capable of detecting large human joint motions, such as neck twisting, neck bending, and wrist, finger, and elbow movements. Similarly, these hydrogels are capable of monitoring different subtle human motions such as speaking and differentiating between different words, swallowing, and drinking through larynx vibrations. Besides these large and subtle human motions, hydrogels have the ability to differentiate and reproduce different written words with reliability. These LGA-regulated hydrogels have potential applications in electric skins, medical monitoring, soft robotics, and flexible touch panels.

Sustainable fleet management seeks to deliver the best service with a standard of service defined by state regulatory bodies by utilizing and managing large fleets of vehicles in the most efficient, productive, and cost-effective way. Public transport service providers thus seek alternative ways to minimize cost as well as air pollution and carbon emissions from the transportation sector. This study develops a total cost of ownership (TCO) framework for evaluation of different alternative fuel options (diesel, compressed natural gas [CNG], and electric) for bus public transportation based on real-world driving conditions. Electric, CNG, and diesel buses are compared from the life cycle perspective by quantifying a set of sustainability indicators including global warming potential, particulate matter formation, human health impacts, and TCO. According to the results, it was found that TCO of electric buses is less than that of diesel and CNG buses. Specifically, TCO of electric buses is 15% less than that of diesel buses, and compared with CNG it is 5% less over a period of 10 years of use. The proposed framework provides a quantitative basis for a sustainable fleet management approach for public bus service providers.

ABSTRACTObjectivesThe focus of the present research is to develop printlet formulations of pyrimethamine (PMT).MethodsPrintlets formulation of PMT were developed by screening design by varying laser scanning speed, Kollidon® VA 64, polyvinylpyrrolidone, and disintegrant.ResultsLaser scanning speed, Kollidon® VA, and disintegrant had statistically significant effect on hardness, disintegration time, and/or dissolution (p < 0.05). Dissolution was almost 100% in 30 min. X-ray powder diffraction indicated partial amorphous transformation of the crystalline drug. Pharmacokinetic and anti-toxoplasma activity profiles of the printlets and compressed tablets were superimposable with no statistical difference (p > 0.05).ConclusionClinical performance of the printlets would be similar to the compressed tablets.

Solvent-aided thermal recovery processes have been suggested and implemented to reduce the environmental impact of steam-based heavy oil and bitumen production. The injected solvents often undergo dissolution (exsolution) into (from) the oil phase throughout the heavy oil and bitumen recovery processes. New experimental data at elevated pressures and temperatures are essential to better understand the dissolution and dissolution kinetics of various solvents. To eliminate this gap, a new experimental setup was developed to study the kinetics of exsolution and dissolution of gases. The developed setup was used to study the exsolution of ethane from ethane-saturated heptane and the dissolution of ethane in heptane in a temperature range of 60 to 120 °C. An analytical model was adapted to model the experiments and estimate the diffusion coefficients of exsolution and dissolution of the ethane/heptane system. The results indicate that the exsolution of ethane from heptane is much faster compared to its dissolution. The molecular diffusion coefficients for exsolution and dissolution were found to be in the range of (2.02–5.44) × 10–6and (1.76–11.80) × 10–8m2/s, respectively. The measured experimental data were modeled using the Arrhenius-type kinetics. The results revealed lower activation energy for the exsolution of ethane from ethane-saturated heptane compared to its dissolution. The reported dissolution and exsolution data sets find applications in the design, simulation, and optimization of solvent-aided thermal recovery of bitumen/heavy oil and various chemical processes.

This study is focused on the design of a spectrophotometric technique for the liquid–liquid microextraction (Ss-LLME) of aluminum from water and hair samples to use a supramolecular solvent. Al (III)-curcumin complex was quantitatively isolated and preconcentrated using supramolecular solvent liquid–liquid microextraction at pH 6.0. The measured molar absorptivity for the compound was 9.28 × 104L mol−1cm−1at 430 nm. Beers law was applicable in the concentration range of 0.1–12.0 µg mL−1. Extraction efficiency influencing factors like solution pH (6.0), mass of chelating agent (0.1 mg), sample volume (20 mL), type and volume of supramolecular solvent (decanol, 0.1 mL), the volume of THF (0.2 mL) and matrix effect was optimized. Parameters of merit like a limit of detection (0.056 mg L−1) and limit of quantification (0.189 mg L−1), preconcentration factors (50), enrichment factor (50), and determined relative standard deviations. The new method's precision was determined by analyzing verified reference materials TMDA-64.3 fortified water and NCS ZC81002B human hair. The procedure was applied to determination of aluminum contents of hair and water samples.

Ponseti treatment has been well-established as the gold standard for the treatment of idiopathic clubfoot in high-income countries and middle- and low-income countries (LMICs). The tenotomy is usually performed in the clinic using a scalpel blade under local anesthesia. However, we believe that by adapting the technique from Minkowitz et al. to a low-resource setting, we can help address some of the known barriers to Ponseti care. Using a needle instead of a blade makes the procedure less cumbersome easier to learn and easier to understand for the provider, family and the patient. We were able show that the needle tenotomy technique can be implemented in a low-resource setting like Pakistan, and can be performed using only one assistant and materials that are locally and readily available for the same cost This paper and its attached educational videos can help spread the technique among providers in low-resource settings.

The focus of this research was to understand the effects of formulation and processing variables on the very-rapidly dissolving printlets of isoniazid (INH) manufactured by the selective laser sintering (SLS) three-dimensional (3D) printing method, and to characterize their physicochemical properties, stability, and pharmacokinetics. Fifteen printlet formulations were manufactured by varying the laser scanning speed (400–500 mm/s, X1), surface temperature (100–110 °C, X2), and croscarmellose sodium (CCS, %, X3), and the responses measured were weight (Y1), hardness (Y2), disintegration time (DT, Y3), and dissolution (Y4). Laser scanning was the most important processing factor affecting the responses. DT was very rapid (≥3 s), and dissolution (>99%) was completed within 3 min. The root-mean-square error in the studied responses was low and analysis of variance (ANOVA) was statistically significant (p< 0.05). X-ray micro-computed tomography (micro-CT) images showed very porous structures with 24.6–34.4% porosity. X-ray powder diffraction and differential scanning calorimetry data indicated partial conversion of the crystalline drug into an amorphous form. The printlets were stable at 40 °C/75% RH with no significant changes in assay and dissolution. Pharmacokinetic profiles of the printlets and compressed tablets were superimposable. In conclusion, the rapidly dissolving printlets of the INH were stable, and oral bioavailability was similar to that of compositionally identical compressed tablets.

People have always been concerned about the quality of the products they use--especially those products that are consumed or used for medicinal purposes. Regulation of medicinal products began with inspection [...]

The authors developed and characterized self-nanoemulsified drug delivery sYstems of coenzyme Q10 using R and S enantiomers of limonene and evaluated the progress of emulsification and drug-release kinetics. Self-emulsified systems [...]

The rapid urbanization, economic growth, and improved living standards in developing countries are causing a significant increase in the amount of solid waste generated. To ensure a healthy environment for city residents and effectively manage waste resources, it is crucial to employ scientific methods as decision-making tools. However, the lack of competent institutions, financial and technical capabilities, and irresponsible social behavior hinder the implementation of an integrated and sustainable solid waste management (SWM) system. To address these challenges, researchers have proposed an optimized solution using mathematical modeling and GIS. This solution aims to enhance collection efficiency, optimize transportation, and maximize resource recovery and waste processing. By using linear mathematical modeling and the Arc-GIS Network Analyst tool, the study achieved a 13% route optimization in Phase 7 Hayatabad, indicating the potential for a more sustainable and cost-effective municipal solid waste (MSW) collection system in urban Peshawar. The study also explored different scenarios, such as increasing waste collection efficiency and implementing waste-to-energy technologies, which resulted in improved economic viability and reduced payback periods. Overall, the research highlights the need for adaptive strategies and policy reforms to establish sustainable and efficient waste management systems in rapidly growing cities, fostering a cleaner and more environmentally responsible urban future.

The authors investigated the transdermal permeation efficiency of genistein through abdominal human cadaver skin and the effect of permeation enhancers dimethylformamide (DMF), dimethylsulfoxide (DMSO), olive oil, and alcohol on the [...]

The authors evaluate the effect of microcrystalline cellulose (MCC) on the tableting performance, surface roughness, and dissolution properties of a dry adsorbed self-nanoemulsified powdered formulation. Heckel analysis was used to [...]

The authors summarize the current status of the development strategies of insulin drug delivery systems in the pharmaceutical industry, various challenges associated with the oral delivery of insulin, and how [...]

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Technique, indications and outcomes of laparoscopic splenectomy in stable trauma patients have not been well described yet. All hemodynamically non-compromised abdominal trauma patients who underwent splenectomy from 1/2013 to 12/2017 at our Level 1 trauma center were included. Demographic and clinical data were collected and analysed with per-protocol and an intention-to-treat comparison between open vs laparoscopic groups. 49 splenectomies were performed (16 laparoscopic, 33 open). Among the laparoscopic group, 81% were successfully completed laparoscopically. Laparoscopy was associated with a higher incidence of concomitant surgical procedures (p0.016), longer operative times, but a significantly faster return of bowel function and oral diet without reoperations. No significant differences were demonstrated in morbidity, mortality, length of stay, or long-term complications, although laparoscopic had lower surgical site infection (0 vs 21%).The isolated splenic injury sub-analysis included 25 splenectomies,76% (19) open and 24% (6) laparoscopic and confirmed reduction in post-operative morbidity (40 vs 57%), blood transfusion (0 vs 48%), ICU admission (20 vs 57%) and overall LOS (7 vs 9 days) in the laparoscopic group. Laparoscopic splenectomy is a safe and effective technique for hemodynamically stable patients with splenic trauma and may represent an advantageous alternative to open splenectomy in terms of post-operative recovery and morbidity.

Graft copolymerization technique was used to synthesize novel biopolymer based terpolymeric hydrogels of xanthan gum (Gx), acrylic acid and N-Isopropyl acrylamide (NIPAM) by using chemical crosslinker N,N′-methylene bisacrylamide (MBA), ammonium persulphate (APS) as a redox initiator and sodium dodecyl sulphate (SDS) for particle size stabilization. The synthesized hydrogels were characterized through FT-IR and SEM techniques, which confirmed the hydrogels formation. Detailed rheology was investigated through applying various rheological models like Bingham model, modified Bingham model and Ostwald power law model to the hydrogels which revealed that the hydrogels were appeared to have shear thinning, non-Newtonian behavior and more elastic. Modified Bingham model provided best fit understanding to our prepared materials. The maximum activation energy (Ea) 13.87 kJ/mol was obtained for composition having more Gx compared to others, showing a strong relationship with viscosity. The hydrogels has potential to find applications in food industry, cosmetics, degradation of dyes and removal of heavy metals from waste water.

Crew Resource Management (CRM) training incorporates methods such as simulation, debrief, and teamwork training to emphasize human factors skills. This systematic review aimed to assess differences in CRM between UK and USA trauma personnel.

A series of three fluorine containing and three non‐fluorinated Diels–Alder step‐growth polyarylene polymers and copolymers was synthesized via conventional oil bath heating (days/weeks). A drastic time reduction was realized with a microwave‐assisted polymerization (hours). The polymers were characterized by multinuclear (1H, 13C, and 19F) NMR and attenuated total reflectance Fourier transform infrared (ATR‐FTIR) spectroscopy, thermal analysis (thermogravimetric analysis [TGA], differential scanning calorimetry [DSC], and dynamic mechanical analysis [DMA]), gel permeation chromatography, X‐ray diffraction (XRD), water contact analysis, and refractive index (RI) measurements. The NMR spectra indicated a mixture of paraand metaconformations through the polymer backbone increasing to more parawith greater fluorine content. TGA revealed the fluorine‐containing polyarylenes possessed the highest char yields at almost 80% at 1000°C under nitrogen, and all the polyarylenes possessed onset of degradation temperatures above 550°C under nitrogen and air atmospheres. XRD analysis indicated more ordering for the fluorine‐containing polyarylenes which afforded the high char yields. DMA gave storage moduli values in the range of 1–10 GPa for the polyarylenes. Molecular weights for all samples were above 100 kg/mol. Water contact angles did not change with fluorine content due to the shielding effect of the pendant phenyl groups. However, the RI decreased to 1.6497 at 632.8 nm for the polyarylene with the highest fluorine content. Three polyarylenes and their fluorinated analogs were synthesized using conventional heating, but microwave‐assisted polymerization dramatically reduced reaction times. Full characterization indicated high thermal stability with high char yields at 1000°C. The refractive index was tailorable but the water contact angle did not change with the fluorinated polyarylene.

Nasogastric tubes are used frequently in surgical patients for bowel decompression, provision of enteral nutritional support and preventing aspiration of gastric contents. There is no conclusive research into the risk of COVID-19 transmission associated with nasogastric tube insertion, although evidence from the severe acute respiratory syndrome outbreak appears to suggest that there is no increased risk of transmission. However, close contact with a COVID-19 patient, especially those displaying respiratory symptoms, is likely to increase the risk of transmission. Nasogastric tube insertion requires increased time spent at a patient's bedside and can also cause pharyngeal irritation, resulting in coughing. In addition, the nasogastric tube can expose the healthcare worker to potentially infectious saliva. Therefore, there is a clear need for increased evidence regarding the risk of transmission associated with nasogastric tube insertion, to ensure that such risks can be mitigated.

•Enteral nutrition results in a lower mortality rate and fewer abdominal complications.•EN results in a longer time spent in the hospital and time to closure•EN resulted in a higher incidence of pneumonia.

The TiO2dispersed physically cross-linked polymer hydrogels were synthesized through a single step free radical addition polymerization mechanism based on acrylic acid and gum Arabic (GA) as polymer constituents, and ferric ions (Fe3+) as physical cross-linker. The effect of TiO2powder was investigated on thermal and mechanical properties of the hydrogels by dispersion of 0.01, 0.02 and 0.03 g of TiO2in hydrogels. The prepared hydrogels were successfully characterized through FTIR, XRD, SEM and thermogravimetric analysis (TGA). For the mechanical properties, dynamic mechanical analysis and universal testing machine (UTM) were used. The DMA results showed that the storage modulus was increased with the TiO2, while UTM results showed that 0.02 g of TiO2powder significantly enhanced the fracture stress, elastic modulus, toughness and stretchability by 4514%, 4328%, 4124% and 20%, respectively, compared to the virgin hydrogels. Cole–Cole plot confirmed the homogeneity and viscoelastic behavior of the system, while manual load bearing and shape memory test showed that the hydrogels bear a load of 2.5 kg for a long time and it is recovered within 10 s to its original state. The materials can be applied for the synthesis of artificial body parts in the field of bio-engineering. The use of un-modified GA for the synthesis of hydrogels will open a new window for the researchers working in this field.

Orange peel powder was impregnated with magnetic nanoparticles through co-precipitation with Fe3O4nanoparticles and used for the removal of Ni(II) from aqueous solutions. The adsorbent magnetic nanoparticles orange peel powder (MNP-OPP) was characterized by Fourier-transform infrared spectroscopy for surface functional group and scanning electron microscope for the surface morphology. The effectiveness of Ni(II) removal was studied systematically as a function of solution pH 2–7, amount of adsorbent 20–220 mg, contact time 20–60 min, initial metal ion concentration 200–120 mg L–1and temperature 303–363 K. Maximum uptake of Ni(II) (98.12%) was observed at pH 7 with 60 min agitation time. The kinetic studies showed that the data followed second-order kinetics with a correlation coefficient of 0.9948. Adsorption isotherms show that the data fitted to Langmuir adsorption isotherm (R2= 0.9954) with the monolayer adsorption capacity (Q0) of 110.12 mg g–1. The thermodynamic study revealed that the adsorption of Ni(II) ions onto the MNP-OPP composite was spontaneous and endothermic. The effect of different coexisting ions like alkali, alkaline earth metals and transition metals was studied and the results revealed that orange peel with magnetic nanoparticle composite can be used for removal of Ni(II) from water samples as an alternative adsorbent. The method was successfully applied to real environmental water like tap water, canal water and river water with quantitative % adsorption results.

The development of biocompatible, cost effective and more efficient materials to control or inhibit the growth of microorganisms in necessary to fight against resistant microbes. Here, we demonstrate the synthesis of nickel oxide-incorporated polyaniline/polyvinyl alcohol (PANI/PVA/NiOx) composite material by single-step polymerization and its application as antibacterial agent. The composite films were characterized using UV-visible spectroscopy (UV-Vis), Thermogravimetric analysis (TGA), Fourier Transform Infrared spectroscopy (FTIR), X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). UV-Vis spectra revealed the enhancement in absorption properties of PANI/PVA/NiOx with optimum 5% incorporation of NiOx. TGA results indicated slightly enhanced thermal stability of the PANI/PVA/NiOx composite film as compared to PANI/PVA. FTIR spectra for composites revealed the existence of NiOx in polymers. However the crystallinity of PANI/PVA was not much affected. The antibacterial activity of the prepared composites was examined against four different gram negative bacteria, Salmonella, Shigella, Pseudomonas and Escherichia coli (E. coli). The composite exhibited excellent antibacterial activity against E. coli, Salmonella and Shigella while pseudomonas showed some resistance. Based on the results, PANI/PVA/ NiOx (5%) composite showed the highest activity against the tested bacterial strains, thus showing its potential to be used as an effective antibacterial agent.

The metabolic and circulatory disturbances in patients with septic shock results in a high mortality rate. There is a lack of high-level evidence on the optimal approach. We present a meta-analysis elucidating the outcomes of regimes with only noradrenaline versus a combination of noradrenaline and vasopressin in managing septic shock.

An upsurge of terrorist activity has occurred in the past two decades. As part of this, explosive devices continue to be extensively deployed against civilians in wide-ranging environments. Bombings remain the leading worldwide cause of civilian fatalities due to terrorism. This demands an understanding of modern terrorist bombing trends to inform mitigation strategy. The objective of this study was to identify the occurrence and severity of bombings against civilian targets in diverse attack settings, and to establish corresponding blast injury profiles. Data was obtained from analysis of the Global Terrorism Database (GTD) and a meta-analysis of blast injury data derived from the PubMed database. Closed environment explosions were associated with significantly greater (p < 0.05) mortality than in open spaces. The injury profiles were found to be influenced by attack setting, with higher rates of primary injury on trains and buses, and secondary injury in open space.

The UK military commitment to United Nations operations has led to a new challenge in identifying and developing skill sets required for humanitarian operations. The last two decades have concentrated on kinetic operations, with haemorrhage control being the main driver. The austere location and prolonged evacuation timelines have led to identifying management strategies of conditions that would previously have been evacuated to higher echelons of care. The Defence Medical Services have a multifaceted approach to training military personnel for operations, varying from regular exposure to high-acuity trauma and general surgery within their host NHS Trust, to validated training platforms that evolve continually to address the training needs demanded by differing fields of conflict.

The authors explored the use of simplex optimization and artificial neural network (ANN) procedures to obtain coated beads with desired release characteristics by mixing several beads of known strengths and [...]

Magnetic solid phase extraction methods for the preconcentration of Pd(II) and Cd(II) was developed by using reduced graphene oxide-polychloroprene impregnated with magnetic nanoparticle (MNPs- RGO-PCP) as an adsorbent. MNPs-RGO-PCP was synthesized and characterized by using Fourier transformation infrared, X-ray diffraction (XRD) and scanning electron microscope. Factors affecting extraction efficiency of the adsorbents such as solution pH, vortex time, adsorbent dose, sample volume and desorption condition were determined and optimized. Analytical parameters such as limit of detection, limit of quantification, linear range, preconcentration factors, enhancement factors and % relative standard deviations were determined under optimized experimental condition. Kinetic study shows that the adsorption of Pb(II) and Cd(II) on MNPs-RGO-PCP follows pseudo- second-order kinetics. The values of thermodynamic parameters such as enthalpy (ΔH°), Gibbs free energy (ΔG°) and entropy (ΔS°) show that the adsorption process is endothermic, spontaneous and feasible in nature. The developed method was applied to certified reference materials such as TMDA 52.2 environmental water, TMDA 62.2 environmental water and SPS-WW2 wastewater with satisfied recovery results. The method was also applied to real environmental samples such as dam water, river water and water from industrial effluent with good addition recovery results.