the complexation of alkali metal cations by the water-soluble p-sulfonic acid calix(4)arenewas thermodynamically characterized using spectrophotometeric data which are consistentwith the formation of a 1:1 complex resulting from electrostatic interactions between thesulfonato groups and alkali metal cations. in this study, we determined the formationconstants (log k) of the complexes and have c...

Diosgenin (Figure 1) is a bioactive steroidal sapogenin belonging to the triterpene group and is of great interest to the pharmaceutical industry [1]. It is the aglycone formed by the hydrolysis of saponin dioscin (Figure 1), a compound found in Dioscorea spp. [2]. It serves as an important starting material for the production of corticosteroids, sexual hormones, oral contraceptives as well as ...

UV-vis spectrophotometeric, transmission electron microscopy (TEM) and viscometric techniques were used for the formation, characterization and kinetics of silver sol formation using silver nitrate as source of silver, paracetamol as reducing agent and cetyltrimethylammonium bromide (CTAB) as the stabilizer in absence and presence of poly(vinyl alcohol) (PVA). The sigmoidal curve of absorbance ...

A sensitive preconcentration procedure for spectrophotometeric determination of aluminum was developed. Aluminum as aluminon complex is adsorbed on microcrystalline naphthalene. The naphthalene containing the complex is dissolved in 3 mL of acetone and its absorbance is measured at 544 nm. The effect of various factors on the preconcentration of aluminum was investigated. The calibration graph ...

Selenium is an essential trace element that is important in proper immune system functioning and in free radical control. Selenium protects against heart weakness and degeneration. It is crucial for optimal health and detoxification. Selenium is required for the production of thyroid hormones. The body only needs a small amount. Nevertheless, the selenium mineral is an essential mineral which t...

Different minerals including ( Na+, K+ and Ca++) in addition to iron copper) were determined different algae samples collected from some region at Al –Gabal –Khder coast (Libya). The (Ulva algae, Cladophora Polysiphonia Laurencia algae).The mineral contents measured by Flamephotometer, while the (iron levels estimated spectrophotometeric method. results showed variations between of studied samp...

Two simple, economical, precise and reproducible visible spectrophotmetric methods have been developed for the estimation of doxycycline in tablet formulation. The developed methods are based on the formation of chloroform extractable complex of doxycycline with bromo phenol blue and safranine in double distilled water. The complex with bromo phenol blue (method I) shows absorbance maxima at 41...