Quantitation of Sulfacetamide, Sulfadiazine, Sulfamerazine and Sulfame Thazine in Various Cominations Dsing High-Performance Liquid Chromatography

A reverse phase high-performance liquid chromatography method for the quantitation of sulfacetamide, sulfadiazine, sulfamerazine, and sulfamethazine in various combinations has been developed. The method is simple, accurate, precise and reproducible. The percent relative standard deviations based on 6 injections were 2.1, 0.6, 1.9, and 1.6 for sulfacetamide, sulfadiazine, sulfamerazine, and sulfamethazine, respectively. The ratio of peak heights (drug/internal standard) wer closely related (r value 0.99 or better) to concentrations (± 20% of the standard solution concentrations). The results of synthetic mixtures showed quantitative recovery and method was successfully applied to commercial dosage forms (tablets and suspension). Extraction of sulfa drugs from the dosage forms required a very simple procedure.     

A Study of The Moisture-Uptake Kinetics of a Hygroscopic Pharmaceutical Powder

The moisture-uptake kinetics of a hygroscopic powder, sodium heparin contained in a cylindrical container, was determined using a novel moisture-uptake measuring device under a constant convective air flow. The amount of moisture uptake increased with the increase in the relative humidity of the air. The effect of powder-bed height on the total amount of moisture uptake was found to be significant only at the highest relative humidity (75%) evaluated in this study. However, the percent of weight increase of the powder as a result of moisture uptake decreases as the height of the powder bed increases. The results of this study are explained by the dynamic nature of the moisture-uptake process associated with the instrument.     

Use of Difunctional Compounds During Rapid Steam Hydrolysis (Rash) Pretreatment

Mixed hardwood chips were treated with difunctional compounds as catalysts to study the reaction of wood with steam. The Rapid Steam Hydrolysis (RASH) pretreatment process was used for steam treatment. The difunctional compounds studied were maleic anhydride, phthalic anhydride, isophthalic acid, and terephthalic acid at 1.5% concentration based on dry wood weight. RASH pretreatment was performed for one minute at 180°C, 200°, 220°C, 230°C, 240°C, and 260°C. These compounds strongly modified the RASH pretreated material, especially the physical structure. Overall recovery of the pretreated catalyzed and uncatalyzed solids decreased with an increase in RASH temperatures. Catalyst addition did not make a difference on the recovery of pretreated solids. Cellulose degradation increased with temperature for catalyzed systems. Hemicellulose solubilization and degradation were extremely sensitive to the type of catalyst and RASH temperatures. Almost all of the hemicellulose was lost at higher temperatures. Lignin losses did not appear to be affected by the addition of catalyst except at 260°C. Enzymatic rates were improved by addition of the catalysts, especially at the lower temperatures. The maleic anhydride gave the highest enzymatic rates at all temperatures, and phthalic anhydride gave the second highest. The water solubles generally followed the same trends as the enzymatic hydrolysis rates and increased with the addition of catalysts, especially maleic anhydride.     

A Review of the Common Neurodegenerative Disorders: Current Therapeutic Approaches and the Potential Role of Nanotherapeutics

Neurodegenerative disorders are primarily characterized by neuron loss. The most common neurodegenerative disorders include Alzheimer’s and Parkinson’s disease. Although there are several medicines currently approved for managing neurodegenerative disorders, a large majority of them only help with associated symptoms. This lack of pathogenesis-targeting therapies is primarily due to the restrictive effects of the blood–brain barrier (BBB), which keeps close to 99% of all “foreign substances” out of the brain. Since their discovery, nanoparticles have been successfully used for targeted delivery into many organs, including the brain. This review briefly describes the pathophysiology of Alzheimer’s, Parkinson’s disease, and amyotrophic lateral sclerosis, and their current management approaches. We then highlight the major challenges of brain-drug delivery, followed by the role of nanotherapeutics for the diagnosis and treatment of various neurological disorders.     

Structural Evolution of Q-Carbon and Nanodiamonds

This article provides insights pertaining to the first-order phase transformation involved in the growth of densely packed Q-carbon and nanodiamonds by nanosecond laser melting and quenching of diamond-like carbon (DLC) thin films. DLC films with different sp³ content were melted rapidly in a controlled way in super-undercooled state and quenched, leading to formation of distinct nanostructures, i.e., nanodiamonds, Q-carbon, and Q-carbon nanocomposites. This analysis provides direct evidence of the dependence of the super-undercooling on the structural evolution of Q-carbon. Finite element heat flow calculations showed that the super-undercooling varies monotonically with the sp³ content. The phenomenon of solid–liquid interfacial instability during directional solidification from the melt state is studied in detail. The resulting lateral segregation leads to formation of cellular filamentary Q-carbon nanostructures. The dependence of the cell size and wavelength at the onset of instability on the sp³ content of DLC thin films was modeled based on perturbation theory.     

Organochlorine pesticide residues in poultry feed,chicken muscle and eggs at a poultry farm in Punjab,India

Animals intended for human food may absorb pesticides from residues in their feed, water or during direct/indirect exposure in the course of pest control. The objective of the present investigation was to monitor organochlorine pesticide residues in poultry feed, chicken muscle and eggs at a selected poultry farm. The samples were Soxhlet extracted for 8 h in 200 mL hexane–acetone (1:1, v/v) mixture. The clean‐up of the samples was performed by silica gel column chromatography and analysis was done on a gas chromatograph equipped with an electron capture detector. The mean total hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT), endosulfan sulfate and heptachlor epoxide residues were 0.65, 0.91, 0.42 and 0.02 mg kg^?1, respectively, in feed while respective values for chicken muscle were 0.11, 0.24, 0.10 and 0.07 mg kg^?1. Higher residues were encountered in eggs as compared to muscle. None of the muscle samples exceeded maximum residue limits (MRL) for organochlorine pesticides, while all egg samples had values above the MRL for HCH and heptachlor epoxide and seven egg samples exceeded MRL for DDT residues. The results indicated that poultry feed could be one of the major sources of contamination for chicken and eggs. These residues are present despite complete ban on the use of technical HCH and DDT for agricultural purposes in India. Copyright © 2005 Society of Chemical Industry     

The Use of Lewis Acids During Rapid Steam Hydrolysis

Mixed hardwood chips were treated with various concentrations of aluminum chloride hexahydrate, aluminum sulfate hydrate, and ferric chloride and were subjected to rapid steam hydrolysis pretreatment (RASH). The three levels included 0.01, 0.03, and 0.05 moles of catalyst per 1000 grams of wood. Rapid steam hydrolysis (RASH) was done from 180° to 260°C at 20°C intervals for one minute. The Lewis acid catalyst affected the overall recovery yield of solids, the recovery values of the individual components, the enzymatic rates, and the methanol and water solubility. Overall recovery of pretreated solids generally decreased with the increase in levels of the catalyst. The one exception was AlCl₃ ·6H₂O where the minimum recovery levels were reached at 0.03 moles per 1000 grams of wood and increased at the higher level of catalyst. Cellulose degradation occurred in the temperature range of 250° to 260°C for the control and at the two lower concentrations of the catalyst. At the higher levels of catalyst, appreciable amounts of cellulose degradation occurred at lower temperatures. Hemicellulose solubilization and degradation were extremely sensitive to the RASH temperature and to the levels of catalyst. Almost all hemicellulose was lost at high temperatures or at high levels of catalyst. Losses of lignin appeared to be affected mainly by the RASH temperature and not by the changes in the levels of catalyst.

In contrast, both the temperature and the level of catalyst strongly affected the rates of enzymatic hydrolysis. Generally, the intermediate level of catalyst seemed to give the highest rates of enzymatic hydrolysis at the lowest temperature. Methanol and water solubles increased in the presence of the catalyst and reached a maximum at levels of 0.03 moles between 230° to 250°C.     

Investigations of lanthanum doping on magnetic properties of nano cobalt ferrites

The magnetic properties of nano-crystallite cobalt lanthanum ferrite (CoLa_xFe_2-x O₄) with varied quantities of lanthanum (x = 0, 0.1, 0.15, 0.2, 0.25, 0.3) prepared by co-precipitation method have been studied by vibrating sample magnetometer (VSM) and LCR meter. X-ray diffraction (XRD) and transmission electron microscopy (TEM) confirmed the size, structure, and morphology of the ferrite samples. The average crystallite size varied from 17.83 nm to 49.99 nm. All the samples, although, in nano range, show significant hysteresis. The saturation magnetization (M_s) values decreased from 60.57 emu/g to 30.15 emu/g. The remanence (M_R) fell from 10.85 emu/g to 6.39 emu/g. Doping with lanthanum La³⁺ ions modulates significantly the magnetic properties of cobalt spinel ferrites without sacrificing the ferromagnetic character.     

Evaluation of Robustness of the Biosurfactant Derived from Balanites aegyptiaca (L.) Del.

Balanites aegyptiaca (L.) Del. is a widely distributed xerophytic multipurpose tree. The mesocarp of the fruit of B. aegyptiaca has detergent properties due to the presence of saponins. The stability potential of this biosurfactant at varying pH, temperature, and salinity has not been explored so far. In the present study, the relative surface tensions of five different concentrations of the biosurfactant were studied at different temperatures, salinity, and under pH conditions. This study reveals that this biosurfactant retains its activity over a wide range of pH (3–11) and at high salinity (7% NaCl). It is a thermostable cationic surfactant; surfactant activity was recorded even at 100 °C with the lowest relative surface tension of 0.47. High oil displacement (18.00 mm) was observed when studied with petrol. This biosurfactant was found to have a high emulsification index (E₂₄) of 70% with mustard oil. These results indicate that biosurfactant derived from B. aegyptiaca may find use in a wide range of sectors such as textile, food, cosmetics, oil recovery, and healthcare under a wide range of physical and chemical conditions. It offers an efficient, economically viable, and plant-derived alternative to synthetic detergents and adds a way to maintain a sustainable environment.