Electrophoretic Techniques Research Articles

Improved Hydrogen Gas Sensing Performance of Carbon Nanotube Synthesized Using Microwave Oven

Obtaining a high-performance hydrogen (H2) gas sensor based on carbon nanotube (CNT) remains challenging. In this view, two CNT samples such as untreated (R-CNT) and nitric acid (HNO3)-treated (called functionalized or F-CNT in short) were deposited on the SiO2/Si substrate using an electrophoretic deposition technique. The structure, morphology, and electrical characteristics of these samples were evaluated. Fourier transform infrared (FTIR) spectra confirmed the presence of OH groups at the walls of nanotubes after acid treatment. Moreover, it found the current increased from <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$35 \mu \text{A}$ </tex-math></inline-formula> for R-CNT to 11 mA for F-CNT. In addition, both R-CNT and F-CNT were used to fabricate H2 gas sensors. The sensing capacity of the obtained sensors was measured under the H2 gas exposure range of 20 to 300 ppm operated at room temperature (RT), 50 °C, and 75 °C. The H2 gas sensor made of F-CNT showed a much higher response (368%) and shorter response time (15 s) as well as recovery time (72 s) than the one made using R-CNT. It was asserted that the H2 gas sensing performance of the proposed sensor can significantly be improved via the acid treatment or functionalization of CNT.

Biofunctionalized carbonaceous nanoflakes based efficient electrochemical biosensor for SAA biomarker detection

Swine flu is one of the major causes of death worldwide in both humans as well as in animals. In the biological sample of swine flu patients, there are several biomarkers secreted in which Serum Amyloid A (SAA) is one of the promising biomarker. Based on the concentration of SAA apolipoprotein, swine flu patients can be easily differentiated from the normal subject. Keeping these in view, we report the results of the studies related to the fabrication of an immunosensing platform for SAA apolipoprotein biomarker detection. For the fabrication of the immunosensing platform, we used ultrathin carbonaceous nanoflakes [Graphitic carbon nitride nanoflakes (g-C3N4NFs)] as transducer material. The g-C3N4NFs were prepared by polycondensation of melamine followed by liquid stripping, further treated with 3-(aminopropyl) triethoxysilane (APTES) to introduce amino group moiety. The APTES functionalized g-C3N4NFs were deposited onto ITO coated glass electrode using an electrophoretic deposition technique by providing an optimized DC potential of 30 V for 120 s. Further, biofunctionalization was done by immobilizing the specific anti-SAA monoclonal antibody onto APTES/g-C3N4NFs/ITO electrode via EDC-NHS chemistry and non-specific area were blocked with BSA molecules. Several non-distracting techniques such as X-ray diffraction, scanning electron microscopy, transmission electron microscopy and Fourier-transform infrared spectroscopy were used for the structural, morphological, and chemical characterization of synthesized nanomaterials as well as fabricated electrodes. Moreover, cyclic voltammetry techniques were used for electrochemical characterizations as well as response studies. The fabricated immunosensing platform i.e., BSA/anti-SAA/APTES/g-C3N4NFs/ITO is capable to detect SAA protein with linear detection range of 10–100 μg mL−1, limit of detection of 6.17 μg mL−1 and sensitivity of 2.42 μA mL μg−1cm−2.

Diagnosing Multiple Myeloma and Related Disorders.

This review provides current information on myeloma-related disorders, a group of plasma cell or immunoglobulin (Ig) secreting neoplasms including multiple myeloma, extramedullary plasmacytoma (both cutaneous and noncutaneous variants), solitary osseous plasmacytoma, Waldenström macroglobulinemia/lymphoplasmacytic lymphoma, Ig-secretory B-cell lymphoma, plasma cell leukemia, and monoclonal gammopathy of undetermined significance. The diagnostic procedures commonly used to characterize myeloma-related disorders, including cytopathology, histopathology, polymerase chain reaction for antigen receptor rearrangement, flow cytometry, and electrophoretic techniques are outlined and discussed.

Advances in Mass Spectrometry-Metabolomics Based Approaches.

Highly selective and sensitive analytical techniques are necessary for microbial metabolomics due to the complexity of the microbial sample matrix. Hence, mass spectrometry (MS) has been successfully applied in microbial metabolomics due to its high precision, versatility, sensitivity, and wide dynamic range. The different analytical tools using MS have been employed in microbial metabolomics investigations and can contribute to the discovery or accelerate the search for bioactive substances. The coupling with chromatographic and electrophoretic separation techniques has resulted in more efficient technologies for the analysis of microbial compounds occurring in trace levels. This book chapter describes the current advances in the application of mass spectrometry-based metabolomics in the search for new biologically active agents from microbial sources; the development of new approaches for in silico annotation of natural products; the different technologies employing mass spectrometry imaging to deliver more comprehensive analysis and elucidate the metabolome involved in ecological interactions as they enable visualization of the spatial dispersion of small molecules. We also describe other ambient ionization techniques applied to the fingerprint of microbial natural products and modern techniques such as ion mobility mass spectrometry used to microbial metabolomic analyses and the dereplication of natural microbial products through MS.

Light harvesting hexamolybdenum cluster integrated with the 3D ordered semiconductor inverse opals for optoelectronic property

Solar energy-harvesting materials have significantly contributed to the development of energy-saving applications for several decades. We have mainly used a new concept composed of the electrophoretic deposition technique and photonic crystal structural engineering to understand the tunable light-absorption and electronic conduction properties. A hexamolybdenum cluster compound (denoted as the Mo6 cluster) was successfully functionalized on a tin pyrophosphate semiconductor integrated within an inverse opal photonic crystal. The size of the periodical pores, surface modification, and chemical composition of the infiltration material of the inverse opal film have been investigated to control the photonic bandgap in the visible range and the efficiency of the deposited Mo6 cluster. The photoactive Mo6 clusters act as a visible light harvester and generate an efficient photo-induced current upon light absorption that is enhanced by a slow photon effect occurring at the photonic stopband edges. The electron and proton are transferred in the inorganic-organic network via hydrogen bonds by a hopping mechanism to generate a rapid photoconductivity response during light irradiation. Specific attention focused on the role of humidity and temperature regarding the reproducibility of the experiments and the photosensitivity of the nanocomposite. The suitable tunable photo-induced conduction property in organic-inorganic materials opens a new opportunity for the applicability of cluster-based compounds in visible optoelectronic devices.

D-Ribose-Induced Glycation and Its Attenuation by the Aqueous Extract of Nigella sativa Seeds.

Background and Objectives: Glycation and oxidative stress are the major contributing factors responsible for diabetes and its secondary complications. Aminoguanidine, a hydrazine derivative, is the only approved drug that reduces glycation with its known side effects. As a result, research into medicinal plants with antioxidant and antiglycation properties is beneficial in treating diabetes and its consequences. This investigation aimed to examine the efficacy of the aqueous extract of Nigella sativa seeds against the D-ribose-induced glycation system. Materials and Methods: The suppression of α-amylase and α-glucosidase enzymes were used to assess the antidiabetic capacity. UV-Visible, fluorescence, and FTIR spectroscopy were used to characterize the Nigella sativa seed extract and its efficacy in preventing glycation. The inhibition of albumin glycation, fluorescent advanced glycation end products (AGEs) formation, thiol oxidation, and amyloid formation were used to evaluate the extracts' antiglycation activity. In addition, the extent of glycoxidative DNA damage was analyzed using agarose gel electrophoresis. Results: The IC50 for the extract in the α-amylase and α-glucosidase enzyme inhibition assays were approximately 1.39 ± 0.016 and 1.01 ± 0.022 mg/mL, respectively. Throughout the investigation, it was found that the aqueous extract of Nigella sativa seeds (NSAE) inhibited the level of ketoamine, exerted a considerable drop in fluorescence intensity, and reduced carbonyl production and thiol modification when added to the D-ribose-induced glycation system. In addition, a reduction in the BSA-cross amyloid formation was seen in the Congo red, thioflavin T assay, and electrophoretic techniques. NSAE also exhibited a strong capability for DNA damage protection. Conclusion: It can be concluded that Nigella sativa could be used as a natural antidiabetic, antiglycation treatment and a cost-effective and environmentally friendly source of powerful bioactive chemicals.

Spurious capillary zone electrophoresis pattern in hypercholesterolemic dogs.

Capillary zone electrophoresis (CZE) is a relatively new serum protein electrophoresis method with higher resolution than other electrophoretic techniques. Hypercholesterolemic dogs exhibit a peculiar CZE pattern. Specifically, they have a shoulder or peak immediately next to the albumin peak. We investigated the prevalence of this spurious peak in hypercholesterolemic dogs and its correlation with the serum cholesterol concentration. Moreover, possible discrepancies between the CZE and spectrophotometric (bromocresol green [BCG] method) albumin concentrations in those animals were evaluated, as well as the accuracy in measuring albumin by a different CZE fractionation system. We retrospectively enrolled 500 hypercholesterolemic and normotriglyceridemic dogs. Each electrophoretic curve was inspected visually to identify a spurious peak (prevalence of 68.8%). We chose 120 dogs to further investigate the albumin concentration; CZE albumin was significantly higher than measured using the BCG method. A weak but significant correlation (r = 0.412; p <0.0001) was observed between the magnitude of the spurious peak and the serum cholesterol concentration. Finally, the significant difference between CZE and BCG albumin measurement disappeared (p = 0.92) when the spurious peak was considered as α1-globulins instead of albumin.

Methicillin-Resistant Staphylococcus aureus Membrane Vesicles Inhibit the Proliferation and Induce the Apoptosis of Epithelial Cells.

Staphylococcus aureus, or methicillin-resistant Staphylococcus aureus (MRSA), is the predominant pathogen in skin and soft tissue infections (SSTIs), and MRSA membrane vesicles (MVs) play a pivotal role in bacterial pathogenesis and the modulation of the host immune response. We aimed to investigate the interaction between MRSA MVs and epithelial cells. In this study, MVs were isolated from an MRSA culture supernatant using the ELD method, comprising an electrophoretic technique used in combination with a 300 kDa cut-off dialysis bag. The proteomic analysis of the MRSA MVs via mass spectrometry showed that shared and distinct proteins exist in the MVs from clinical MRSA isolates with different genetic backgrounds, such as health-care-associated MRSA (HA-MRSA) and community-associated MRSA (CA-MRSA). These MRSA MVs were found to suppress the proliferation and increase the apoptosis of HaCaT cells. We conducted qPCR array, quantitative real-time PCR (qRT-PCR), and Western blotting (WB) analyses, and the results indicated that BCL2 antagonist/killer 1 (Bak1) may be involved in the apoptosis of HaCaT epithelial cells. Our findings suggest that MRSA MVs inhibit the proliferation and induce the apoptosis of epithelial cells.

Hybridized high concentration photovoltaic unit with enhanced performance air gap membrane distillation unit via depositing reduced graphene oxide layer upon the condensation plate using electrophoretic deposition technique

Amongst the membrane distillation techniques, the air gap configurations showed an outstanding thermal efficiency, while a decline in productivity was recorded due to the additional thermal and mass resistances. The current study proposes minimizing the additional thermal and mass resistances by altering the condensation process to dropwise condensation. Depositing a layer of reduced graphene oxide using the electrophoretic deposition technique on the copper condensation plate was investigated to obtain a hydrophobic nature and attain dropwise condensation. Moreover, different operating conditions were examined for the optimum conditions, which were 45 V, 30 s, 1 cm, and 0.5 mg/ml, for the applied voltage, deposition time, distance between electrodes, and concentration, respectively. This modified condensation plate was investigated experimentally on the lab-scale test rig and showed an improvement in the productivity of 12.5% and 28.5% at the minimum and maximum feed temperatures, respectively. On the other hand, solar energy was utilized to eliminate the heating source required for the membrane distillation unit. A high concentration photovoltaic (HCPV) unit was introduced numerically in the current work with 36 multijunction cells. Furthermore, a microchannel heat sink was successfully designed to keep the cells from thermal degradation. The numerical results showed that the HCPV system could supply hot water up to 55 °C and produce electric power up to 230 W.

Fabrication of Binder-Free and High Energy Density Yarn Supercapacitor for Wearable Electronics

Textile-based electronics systems are gaining considerable popularity nowadays and the area of wearable electronics technology is going to explode in the near future. Currently, the research on the flexible and wearable energy storage devices, to realize as power sources in wearable electronics, is on the boom. Herein, a flexible yarn-based supercapacitor (YSC) is fabricated utilizing TiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> nanofibers and multiwalled carbon nanotube deposited on carbon yarn through the facile electrophoretic deposition technique for flexible/wearable energy storage application. The binder-free, mechanically strong, and compact deposition of the active materials on carbon yarn promotes the charge/ionic transport. The fabricated YSC device delivers a capacitance of 36.8 mF/cm at 0.1 mA/cm current rate. Moreover, the device shows 90% capacitance retention after 10 000 cycles proving excellent mechanical stability for energy storage. Furthermore, the YSC shows 95% retention after 2000 bending cycles at 0.5 mA/cm, suggesting good flexibility of the device. The YSC device shows a maximum energy density of 11.5 <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">μ</i> Wh/cm and power density of 368 <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">μ</i> W/cm, which is better than many YSCs reported in the literature. Three YSCs are integrated into a wearable fabric and glow a red LED for more than 5 min as demonstrated in the video proving its practical application.

Interfacial modification: The dynamic compression properties and enhancement mechanism of concrete added with micro-nano hierarchical carbon-based fiber

The modification of interfacial characteristics between carbon fiber and matrix (F/M) is one of the most pressing issues in the research related to carbon fiber reinforced concrete (CFRC). Herein, carbon nanotubes were grafted onto the surface of carbon fiber using an ultrasonic-assisted electrophoretic deposition technique to create a carbon-based fiber with micro-nano hierarchical structure (CNTs-CF) for concrete modification. The impact test of concrete (CCMC) added with micro-nano hierarchical carbon-based fiber was carried out by using split Hopkinson pressure bar (SHPB), and the effects of CNTs-CF and strain rate on the dynamic compression mechanical properties of concrete specimens were investigated. The microstructures and interfacial characteristics of CNTs-CF and CCMC were characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The results indicate that the CNTs-CF improves the internal F/M interface toughness due to its synergistic filling, bridging, and crack arresting effects, thus effectively relieving the local stress concentration and enhancing the dynamic compression properties of concrete. In the strain rate range of 50–120 s−1, as compared to CFRC, when the volume content of CNTs-CF is 0.3%, the dynamic compressive strength and peak strain of CCMC increase by 11.98% and 7.16%, respectively. When the volume content of CNTs-CF is 0.4%, the dynamic ultimate strain of CCMC increases by 5.52%.

Two-Dimensional Blue Native/SDS Polyacrylamide Gel Electrophoresis for Analysis of Brazilian Bothrops Snake Venoms.

Viperidae snakes are the most important agents of snakebites in Brazil. The protein composition of snake venoms has been frequently analyzed by means of electrophoretic techniques, but the interaction of proteins in venoms has barely been addressed. An electrophoretic technique that has gained prominence to study this type of interaction is blue native polyacrylamide gel electrophoresis (BN-PAGE), which allows for the high-resolution separation of proteins in their native form. These protein complexes can be further discriminated by a second-dimension gel electrophoresis (SDS-PAGE) from lanes cut from BN-PAGE. Once there is no study on the use of bidimensional BN/SDS-PAGE with snake venoms, this study initially standardized the BN/SDS-PAGE technique in order to evaluate protein interactions in Bothrops atrox, Bothrops erythromelas, and Bothrops jararaca snake venoms. Results of BN/SDS-PAGE showed that native protein complexes were present, and that snake venom metalloproteinases and venom serine proteinases maintained their enzymatic activity after BN/SDS-PAGE. C-type lectin-like proteins were identified by Western blotting. Therefore, bidimensional BN/SDS-PAGE proved to be an easy, practical, and efficient method for separating functional venom proteins according to their assemblage in complexes, as well as to analyze their biological activities in further details.

Transient liquid phase (TLP) bonding of Ti–6Al–4V/AISI 304 stainless steel using Cu/CNT composite interlayer

This paper investigates the idea of using Cu/CNT composite interlayer in the transient liquid phase (TLP) bonding of Ti–6Al–4V/AISI 304 stainless steel. In this investigation, initially TLP was carried out using a pure copper interlayer at 900, 950 and 1000 °C with the holding time 60 min. The TLP joining was then carried out at 900 °C with Cu/CNT interlayer, with the CNT weight percent, ranging from 0 to 3%. CNT was deposited on Cu foils, using electrophoretic deposition technique. Microstructure and mechanical properties of the joints were investigated with optical/electron microscopes, microhardness, and shear tests. Results showed that the interface microstructure can be divided into athermal solidification zone, isothermal solidification zone, and diffusion affected zone. The phase structure and compositions in CNT-containing samples are relatively similar to TLP samples with pure Cu interlayer. Results showed that CNT addition has expanded the diffusion areas and facilitated the diffusion across the interface. CNT addition up to 3 wt. % resulted in a significant increase in hardness up 500 VHN. The increase in hardness in the joint area can be related to the presence of various intermetallic compounds at the TLP region. The correlations between mechanical properties and microstructure and the implications of CNTs for mechanical properties of the joints are discussed.

Fabrication of Electrochemical Biosensor Using Zinc Oxide Nanoflowers for the Detection of Uric Acid

A label-free electrochemical biosensor has been developed using zinc oxide nanoflowers (ZnONFs) for the detection of uric acid concentration in human blood serum. ZnONFs have been synthesized by a hydrothermal process and characterized with several techniques such as ultraviolet–visible (UV–Vis) spectroscopy, Fourier transform infrared spectroscopy (FTIR) studies, X-ray diffraction (XRD) study, Raman spectroscopy, scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HR-TEM) and electrochemical analyzer to confirm the formation of nanoflowers and fabrication of electrode and bio-electrodes for uric acid detection. Zinc Oxide nanoflowers have been deposited onto indium–tin oxide (ITO) substrate through electrophoretic deposition technique, and the biosensor has been fabricated by immobilizing urate oxidase (UOx) enzyme onto ZnONFs/ITO electrode surfaces. Further, electrochemical studies have been performed with immobilized UOx/ZnONFs/ITO bio-electrode as a function of uric acid concentrations. It has been found that the fabricated uric acid biosensor shows a high sensitivity (10.38 μA/mM/cm2) and a limit of detection of 0.13 mM in the range of 0.005 to 1.0 mM. This study demonstrates the potential use of ZnONFs for the construction of sensitive biosensors for uric acid detection.

Capillary electrophoretic methods for classification of methicillin-resistant Staphylococcus aureus (MRSA) clones

This study describes differentiation of methicillin-resistant Staphylococcus aureus (MRSA) isolates belonging to different genotype groups by the combination of electrophoretic techniques, transient isotachophoresis and micellar electrokinetic chromatography. MRSA isolates were separated in fused silica capillary with roughened inner surface prepared by etching with supercritical water. Separation temperature together with the rinsing procedure of the capillary turned out to be the key factors of successful analysis. The individual genotype groups were baseline-resolved in 40 min. Partial separation of the individual isolates within the groups was also observed. Relative standard deviations of the migration times of the isolate zones ranged from 0.32 to 0.79%. In addition, capability of the developed CE method to concentrate and separate MRSA isolates in clinical samples was proved by the analysis of blood sample.

P-017: POINT-OF-CARE DIAGNOSTIC FOR QUANTIFICATION OF FOETAL HAEMOGLOBIN (HB F) LEVELS IN MONITORING HYDROXYUREA THERAPY FOR CHILDREN WITH SICKLE CELL DISEASE (SCD) IN GHANA

Purpose: Sickle cell disease (SCD) potentially causes numerous acute and chronic complications across the lifespan. The majority of patients with SCD live in sub-Saharan Africa and 1 in 50 Ghanaian newborns are affected. Foetal hemoglobin (Hb F) level is a known modulator of the severity of SCD. High levels of Hb F inhibit sickling and correlate with reduced disease morbidity and mortality. Hb F monitoring is also used to assess adherence and response to disease modifying (hydroxyurea) therapy. Standard hemoglobin electrophoretic techniques are unable to quantify Hb F. In resource-limited settings like Ghana, the use of high performance liquid chromatography (HPLC) for Hb F quantification is often challenging due to high cost and unavailability of laboratory equipment and skilled technicians. We report on the performance of a low-cost, point-of-care, microchip based cellulose acetate electrophoresis “Gazelle” compared to HPLC for Hb F quantification in Ghanaian children with SCD. GazelleTM is a fast (<8 minutes), easy-to-use test which can be performed by minimally trained personnel using only a finger-prick volume of blood. Materials and methods: The study was conducted at the paediatric SCD Clinic in Korle Bu Teaching Hospital, Accra, Ghana. Children (age ≥ 1 year to 16 years) known to have sickle cell disease who are on hydroxyurea therapy, and followed at the paediatric sickle cell clinic were enrolled in the study. The study is still ongoing. Results: A total of 110 children were included in the analysis. Gazelle showed a correlation of 0.93 when compared to HPLC (Figure 1). Conclusion: Haemoglobin variants are quantified by Gazelle offering the ability to monitor disease modifying therapy in SCD such as hydroxyurea, where quantification of HbF levels is the key to assessing treatment adherence and determining response to therapy. Gazelle has the potential to be utilized as a POC test for quantification of foetal haemoglobin (Hb F) levels in monitoring hydroxyurea therapy for children with SCD.Hb Quantification Performance of Gazelle compared to HPLC C. SEGBEFIA declares a conflict of interest: Consultancy, Expert: Novartis - Advisory Board / Steering Committee Member Global Blood Therapeutics - DSMB Member P. THOTA declares a conflict of interest: Other: Employee of Hemex Health

Bioinspired synthesis of hematite nanoparticles-reduced graphene oxide composite for application in bisphenol a detection: A new in-sight

Bisphenol A (BPA), one of the well-known environmental endocrine-disrupting compounds, has an effective estrogenic activity that badly impacts the environment and human health. Therefore, an urgent need arises to develop a simple and effective method for BPA detection. Herein, we report novel, disposable and flexible nanoplatforms for electrochemical determination of BPA using carbon cloth electrode supported hematite nanoparticles (α-Fe2O3NPs) on reduced graphene oxide (rGO) composite. The α-Fe2O3NPs@rGO composite was synthesized through a green route using leaves extract of Cinnamomum tamala that acted as a reducing and stabilizing agent for α-Fe2O3NPs followed by the addition of graphene oxide to convert it into rGO. The nanoplatform was fabricated using the electrophoretic deposition technique on carbon cloth (CC) substrate, i.e., (α-Fe2O3NPs@rGO/CC). The analytical performance of α-Fe2O3NPs@rGO/CC nanoplatform is ascribed to the synergistic effect of α-Fe2O3NPs and rGO that resulted in a larger active surface to volume ratio, superior conductivity, and enhanced electrochemical behavior. The fabricated α-Fe2O3NPs@rGO/CC nanoplatform exhibited a broad linear range from 1.9 × 10−10 to 1.00 μM having a higher sensitivity of 33.04 μA (log μM)−1 cm−2 and a low limit of detection of 0.23 μM. It also displayed excellent selectivity, repeatability, reproducibility, and stability with satisfying results. Moreover, the electrochemical nanoplatform helped analyze the real samples to detect BPA with acceptable results. Hence, this nanoplatform could be further utilized to detect other estrogenic analytes.

Synthesis and characterization of CuInS2 nanostructures and their role in solar cell applications

Copper indium sulphide (CuInS2) is regarded as an active material for solar cells owing to its unique optical properties, non-toxicity, low-cost and easy of synthesis. The cost and performance of the solar cell depend not only on the materials, but also on the preparation and fabrication techniques, which are significant for improving the efficiency of the device. In current study, the co-precipitation method was instigated to synthesize the chalcopyrite CuInS2 semiconductor nanoparticles (NPs) and the effects of annealing temperature on the size, agglomeration, functional groups and elemental compositions were investigated. In the next step, CuInS2 films were deposited on a conductive substrate using a stable dispersion by an electrophoretic deposition technique. Subsequently, the synthesized NPs and films were subjected to structural, morphological, optical and elemental analysis. X ray diffraction (XRD) revealed the formation of the tetragonal chalcopyrite CulnS2 NPs at 200 °C and 300 °C with the most prominent peak along the (112) orientation, and the calculated crystallite size ranged from 11.32 to 32.74 nm. Furthermore, the films were characterized by scanning electron microscopy, which showed the surface modifications of the electrophoretically deposited films at moderate voltage. The photovoltaic analysis shows that the cell fabricated at 90 V increases the cell's efficiency up to 1.27%, while the cells fabricated at 100 and 110 V increase the efficiency to 1.13% and 0.83%, respectively.

Zeta potential as a tool for functional materials development

The importance of the isoelectric point for the preparation and characterization of functional materials to understand their behavior and optimize their performance is highlighted, with especial focus on industrial catalysts. In different liquid-phase steps involved in materials synthesis, the knowledge of the surface charge as a function of the pH of the medium is fundamental, since it is the dynamizing agent of processes such as gelation, peptization, coagulation and agglomeration to form solid particles. Therefore, zeta potential (ζ) measurements, often based on electrophoretic migration techniques, are a powerful source of information. The basic principles are introduced to explain through relevant examples the possibilities for materials design. Regarding materials preparation, the measurement of the zeta potential to control the synthesis and coating of supports is reviewed, with special attention to shaped supports. Aspects as the influence of the binders on the supports properties depending on their mutual interaction are analyzed, with example systems based on TiO2 or Al2O3 and natural silicates such as sepiolite. Also, how the knowledge of ζ as a function of pH allows, by choosing the appropriate pH, the preferential impregnation of noble metals on porous supports, as well as the washcoating of dense ceramic monoliths with porous supports. Special attention has been paid to surfaces characterization based on the use of zeta potential measurements to estimate the formation and relative location of species, the apparent surface coverage, or the adsorption and reactivity, to establish synthesis strategies to achieve specific properties.

Relationship between malaria parasitemia and haemoglobin variants in patients attending Rivers State University Teaching Hospital, Port Harcourt, Rivers State, Nigeria

Malaria parasitemia and haemoglobin variants in patients attending Rivers State University Teaching Hospital, Port Harcourt, Rivers State, Nigeria was investigated. Blood samples from 385 patients attending the hospital were collected using sterile syringes into well labelled specimen bottles containing ethylene di-amine tetra acetate (EDTA). The genotype was determined using standard alkaline cellulose acetate electrophoretic technique while standard method was used to determine malaria parasitaemia. Out of the 385 patients examined for haemoglobin variants, the frequency of the genotype was 239(62.1%), 127(33%), 17(4.4%) and 1(0.3%) for HbAA, HbAS, HbSS and HbAC respectively. Malaria parasitemia in HbAA, HbAS, HbSS and HbAC was 170(64.2%), 82(30.9%), 13(4.9%) and 1(0%) respectively. HbAA was significantly (P&lt;0.005) susceptible to malaria than other genotypes. The prevalence of malaria in HbAS 82(30.9%), HbSS 13(4.9%) and HbAC 1(0%) also show significance difference (P&lt;0.05). Patience below the age of 6years with HbS gene had the highest malaria prevalence (21%). Malaria prevalence among males 7(53.8%) and females 6(46.2%) with sickle cell anaemia SCA had no significance difference (p&gt;0.05). Sickle hemoglobin (HbS) gene protection against malaria found in heterozygous hemoglobin (HbAS) was also recorded in patients with homozygous (HbSS) gene. Prevalence of malaria is higher in patients with the normal haemoglobin (HbAA) than in patients with abnormal genes (HbAS and HbSS).