M.S. Attia

Highly sensitive and selective spectrofluorimetric determination of metoclopramide hydrochloride in pharmaceutical tablets and serum samples using Eu3+ ion doped in sol-gel matrix.

A simple, sensitive and selective spectrofluorimetric method for the determination of Metoclopramide hydrochloride (MCP) is developed. The MCP can remarkably enhances the luminescence intensity of the Eu(3+) ion doped in sol-gel matrix at lambda(ex)=380 nm in DMSO at pH 8.7. The intensity of the emission band of Eu(3+) ion doped in sol-gel matrix increases due to energy transfer from MCP to Eu(3+) in the excited state. The enhancement of the emission band of Eu(3+) ion doped in sol-gel matrix at 617 nm was found to be directly proportional to the concentration of MCP with a dynamic range of 5 x 10(-9) - 1.0 x 10(-6) mol L(-1) and detection limit of 2.2 x10(-11) mol L(-1).

Determination of melamine in different milk batches using a novel chemosensor based on the luminescence quenching of Ru(II) carbonyl complex

A novel, simple, sensitive and precise spectrofluorimetric method was developed for measuring the melamine concentration in different milk batch samples. The method was based upon measuring the quenching of the luminescence intensity of the produced yellow colored ruthenium((II)) carbonyl complex of the general formula [Ru(CO)(2)(L)] (where L=anion of tetradentate Schiff base). The Ru((II)) complex exhibited characteristic luminescence band in the visible region. The remarkable quenching of the luminescence intensity of [Ru(CO)(2)(L)] complex by various concentrations of melamine was successfully used as a chemosensor for the assessment of melamine in different milk samples at λ(ex)=400 nm and pH 7.4 in DMSO with a linear dynamic range 1.0 × 10(-6) to 3.0 × 10(-9) mol L(-1) and lower detection limit (LOD) and quantification detection limit (QOD) of 3.3 × 10(-10) and 1.0 × 10(-9) mol L(-1), respectively.

Novel application of pyronin Y fluorophore as high sensitive optical sensor of glucose in human serum

This paper presents a novel, high sensitive, facile and rapid spectrofluorimetric method for the direct assessment of glucose in human serum samples. The strong fluorescence intensity of pyronin Y (PY) is found to be selectively quenched substantially by adding solutions of glucose. Therefore, a new quantitative method to determine glucose could be developed. The noticeable and specific quenching effect of glucose on PY emission could be attributed to the increase in the nonradiative interactions as a result of a charge-transfer excited state with the location of the positive charge at the xanthenes moiety. Various parameters namely, the best working solvent, the proper pH medium in addition to the concentration of PY fluorophore corresponding to maximum fluorescence intensity were closely investigated. Under optimal conditions, the standard curve was linear in the glucose concentration ranges from 5.0×10(-9) to 1.0×10(-6)molL(-1) (r=0.994). The detection limit (S:N=3) (LOD) is 2.9×10(-9)molL(-1). Validation of this approach was done by examining glucose concentration in serum samples of twenty patient and ten health donors. Achieved recovery reached 99.63-100.43% and 99.57-100.70%, respectively, in good agreement with those provided from hospital using traditional method. The relative standard deviations (RSD) were estimated between 0.00-0.78% and 0.15-1.91%, respectively.

Durable diagnosis of seminal vesicle and sexual gland diseases using the nano optical sensor thin film Sm-doxycycline complex.

A new method in which a nano optical sensor for diagnosis of different diseases of seminal vesicle and sexual gland was prepared. The working principle of the method depends on the determination of the fructose concentration in semen of different patients by using nano optical sensor thin film Sm-doxycycline doped in sol-gel matrix. The assay is based on the quenching of the characteristic emission bands of Sm(3+) present in silica doped Sm-doxycycline nanooptode thin film by different fructose concentrations in acetonitrile at λex = 400 nm. This method was optimized for parameters, such as, solvent effect, operational stability, shelf life and interference parameters. Good and reproducible linearity (1 × 10(-9) - 5.0 × 10(-5) mol L(-1)) with a detection limit of 9.0 × 10(-10) mol L(-1) and quantification limit of detection (LOQ) 2.7 × 10(-9) mol L(-1) were obtained. Seminal fructose determination in different patient samples after appropriate dilutions confirmed the reliability of this technique. The method was successfully applied for routine fructose monitoring in human semen samples of different cases such as; obstructive and non-obstructive azoospermia, inflammation of male accessory glands, atrophy of seminal vesicle, congenital vas deferens and retrograde ejaculation.

A novel method for tyrosine assessment in vitro by using fluorescence enhancement of the ion-pair tyrosine-neutral red dye photo probe

A low cost and accurate method for the detection and analytical determination of tyrosine in tablet and blood serum was developed. The method was based upon measuring the fluorescence intensity of the ion associate of neutral red dye and the tyrosine (NRD+ TYR−) at 610 nm in acetonitrile at (pH 9.5, λex = 350 nm). The influence of the different parameters, e.g., pH, solvent, tyrosine concentration and foreign ions concentrations that control the fluorescence intensity of the produced ion associate was critically investigated. The remarkable enhancement of the fluorescence intensity of NRD+ TYR− ion associate in acetonitrile at 610 nm and the quenching of emission band of NRD at 380 nm by various concentrations of tyrosine was successfully used as a photo-probe for the assessment of tyrosine concentration. The calibration plot was achieved over the concentration range 1 × 10−5 to 5 × 10−9 mol L−1 tyrosine with a correlation coefficient of 0.993 and a detection limit of 2.7 × 10−9 mol L−1. The developed method is simple and proceeds without practical artifacts compared to the other determination methods.

Synthesis, Spectroscopic and Thermal Characterization of Copper(II) and Iron(III) Complexes of Folic Acid and Their Absorption Efficiency in the Blood

The absorption efficiency of any drug in blood is of prime importance. Compounds having the general formula: Kn[M(FO)2(H2O)2] · xH2O, where (M = Cu(II) or Fe(III), n = 2 or 1, FO = folate anion, x = 2 or 3 with respect), were prepared, and their absorption efficiency in rodents blood was determined. The obtained compounds were characterized by elemental analysis, infrared as well as thermogravimetric analysis and polarization of light. The results suggest that the two folate complexes were formed in 1 : 2 molar ratio (metal : folic acid) which acted as a bidentate ligand through both carboxylic groups. Polarization of light proved that the folate complexes have symmetric geometry. Biological application proved that Cu(II) and Fe(III) complexes were absorbed more efficiently in rodent blood than folic acid itself.

Modified Amberlite IR120 by Magnetic Nano Iron-Oxide for Uranium Removal

A magnetic sorbent nano-iron oxide (Fe3O4 ) modified Amberlite (IR120) resin (Fe-MA) was prepared. Fe3O4 and Fe-MA resin were characterized by Transmission Electron Microscopy (TEM), X-ray Diffraction (XRD), Scanning Electron Microscope (SEM) images and the energy-dispersive X-ray spectroscopy (EDS). Fe-MA sorption efficiency towards UO 2+ ion has been investigated in batch and column modes. The highly efficiency in batch mode toward UO 2+ ion was observed at pH=3.5 and at contact time=60 min. The data obtained from the batch results reveal that, the equilibrium isotherm and kinetics study were described by both Langmuir isotherm model and pseudo-second-order kinetic. On the other side, the highly efficiency in column mode toward UO 2+ ion was observed to increase at initial concentration 9.55 mmol/L, bed height 15 mm and flow rate 2.7 ml/min. Thomas and Yoon-Nelson models were applied in column mode with regression coefficients R2 range from 0.978 to 0.997 at different conditions. The data obtained in the column mode reveals that, the interfering cations La(III), Ce(III), and Th(IV) can be separated from uranyl UO 2+ ion by using different concentrations of nitric acid eluant.

Spectrofluorimetric Determination of Triamterene in Different Body Fluids and Pharmaceutical Tablets

Abstract A spectrofluorimetric method is used to determine 6-phenylpteridine-2,4,27-triamine in pharmaceutical dosage form, Urine and human serum samples. The method is simple, sensitive, and accurate and based on the fluorescence enhancement with increasing concentration of the highly fluorescent triamterene containing three amino groups in methanol at pH 6.7. The dynamic range for the determination of triamterene is 5×10-10 – 9.5×10-7 mol L-1 with detection limit and quantitative detection limit (LOD and LOQ) of 2x10-10 and 6.6x10-10, mol L-1, respectively. The low values of LOD and LOQ indicate the high sensitivity of the proposed method if compared to previous methods for the determination of triamterene. Percentage recoveries were found to be 99.30 ± 0.65, 98.6 ± 0.75, and 96.60 ± 0.85 for the pharmaceutical tablets, urine, and serum samples, respectively. The results demonstrated the accuracy as well as the precision of the proposed method.

Screening the bio-safety of wheat produced from pretreated grains to enhance tolerance against drought using physiological and spectroscopic methods

Drought is a serious abiotic stress, causes worldwide intensive reduction in crop growth and productivity. Plants in contrast to other organisms, do not enjoy the luxury of being able to change their environment or seeking shelters. In this investigation, wheat grains were pre-soaked for 12h in salicylic acid (SA) and/or thiourea (ThU) prior they were left to grow in dry land (40% field water capacity) until harvest. The bio-safety of the harvested wheat was deduced using technical physiological and spectral methods. The pretreatment using SA up to ( approximately 1.5mmol) viewed homologous protein profile and less flag leaf proline in comparison to the non-stressed wheat. In addition, SA-pretreatment has maintained 70% of the emission intensity of yielded grain. The spectra of FTIR were more or less similar in yielded grain and flag leaf in SA-pretreatment. On the other hand, ThU pretreatment induced varied protein profile, higher proline than normal, reduced the fluorescence emission intensity by 52%, and induced varied FTIR spectra. Pretreatment of SA not only has enhanced wheat productivity but also increased yield and straw productions even above the non-treated-non-stressed wheat plant. In contrast to ThU SA was considered safe for drought-stress alleviation in crop plant agriculture.

Nano-optical Biosensors for Assessment of Food Contaminants

In the last decades, the optical biosensors have great attention, especially, when the biosensor is inserted into a good host such as tetraethoxyorthosilicate (TEOS) polymer and molecular imprinted polymer with no interference. This method gives a transparent nano-optical biosensor with new optical properties to increase the impact of the proposed analytical method which has wide linear range and very low detection limit. In this chapter, the transparent nano-optical sensor is inserted into TEOS polymer and imprinted template in molecular imprinted nanopolymer for the determination of different food contaminants such as different bacteria (Salmonella, Staphylococcus aureus and Campylobacter), Aflatoxin produced by different Aspergillus flavus and Aspergillus parasiticus species of fungi and E. coli bacteria. The nano-optical biosensors were used for the determination of food contaminants in different food samples with a high-performance analytical method.