Authors:Prathikantam Pushpalatha, Rajendra Sarin, Mohd Idris, Mesineni Rao, Tulsidas Baggi, and M. Varma
A rapid, sensitive, and specific high-performance thin-layer chromatographic (HPTLC) method was developed and validated for quantitative determination of free duloxetine (DLX) in human serum. Densitometric analysis of free DLX was carried out at 235 nm after simple liquid-liquid extraction. The method uses thinlayer chromatography (TLC) aluminum plates pre-coated with silica gel G 60 F254 as stationary phase and acetone-benzene-triethylamine (5:4.5:0.5, v/v) as mobile phase for the separation of free DLX from serum constituencies. The calibration curve was linear (r2 = 0.980) in the tested range of 35–140 ng spot−1 with a limit of quantification and detection of 35 and 10 ng spot−1 with the recovery of free DLX in serum ranges from 92.86 to 97.58%. Intra- and inter-day precision (% RSD) values were ≤1.83% and ≤5.66%, respectively. Analysis of free DLX from human serum was successfully performed without interference from endogenous materials and some of the other common drugs of abuse. The method’s ability to quantify free DLX with precision, accuracy, and sensitivity makes it useful in forensic examination.
Differential scanning calorimetry (DSC) has been employed to study the thermal denaturation processes of the main protein
fractions of blood serum. These processes have been compared for albumins (nondefatted (HSA) and fatty acid free (HSAf)),
α,β-globulins, γ-globulins, and their mixtures in aqueous (pH 6.5) and buffer (pH 7.2) solutions. The results have indicated
that α,β-globulins inhibit γ-globulins’ aggregation in buffer solutions. The decrease of stability of HSA and HSAf aqueous
solutions has been observed in the presence of γ-globulins. The mixtures of albumins and γ-globulins have revealed the tendency
to ready aggregation in water. Moreover, the results have suggested that neither γ-globulins nor albumins severely change
the stability of α,β-globulins.
extraction from serum sample. The humanserum standards for calibration were prepared by spiking the standard working solution and IS solution (20 μL of 100 μg/mL; 2 μg) into a pool of blank humanserum (final volume of 100 μL). QC samples at 4 concentrations
Human serum albumin microspheres were labelled with99mTc as a single step kit with radiochemical yields higher than 95%. With respect to the organ distribution in mice, the per cent of injected dose in liver was 78%.
Authors:M. Cantone, G. Gambarini, N. Molho, and L. Pirola
A method for Cr determination in biological samples based on proton nuclear activation is presented. The activation was induced by a 13.8 MeV proton beam of the AVF Cyclotron of Milan University via a (p, n) reaction on the nuclei of the target. For the quantitative determination Cd has been chosen as reference element. The method has been applied to Cr determination in human serum samples. The experimental procedure is described and results are presented and discussed.
Authors:A. Owunwanne, R. O'Mara, D. Weber, and G. Wilson
Dialysis and precipitation methods have been used to study the binding affinity of selected technetium-99m phosphorus radiopharmaceuticals
to human serum proteins. The binding affinities of three different99mTc bone imaging agents were found to be inversely related to their respective clearance rates from blood in vivo. The binding
order showed99mTcPPi>99mTcHEDP>99mTcMDP. The99mTc phosphorus radiopharmaceuticals were bound primarily to alpha globulins. The results suggest that the binding of99mTc phosphorus radiopharmaceuticals to human serum proteins in blood is largely determined by their affinities to the alpha
A simple and rapid method was developed for the determination of selenium in human serum using a pre-irradiation separation technique of ultrafiltration followed by neutron activation analysis via the short-lived activation product77mSe. The method was validated using certified reference material.
Authors:K. Özker, A. Sungur, M. Ercan, N. Ardagil, and N. Aydin
The labelling of human serum albumin /HSA/ with99mTc has been investigated using a chemical method /stannous citrate/ and electrolytically generated tin/II/ ions. A comparative study of various chemical parameters and current intensities has been carried out in order to find the optimal conditions for labelling. The labelling yield was over 95%, for the chemical and electrolytical methods.
Authors:G. Rezaei Behbehani, A. Saboury, S. Tahmasebi Sarvestani, M. Mohebbian, M. Payehghadr, and J. Abedini
The thermodynamic parameters of interaction between theophylline and Human Serum Albumin (HSA) in buffer solution (30 mM)
of pH = 7 at 27 °C was investigated by isothermal titration calorimetry (ITC). The thermodynamic quantities of the binding
mechanism, the number of binding sites (g), the dissociation binding constant (Kd), the molar enthalpy of binding (ΔΗ) and other thermodynamic parameters can be obtained by the extended solvation theory.
Authors:Sigrid Mennickent, Ricardo Fierro, Mario Vega, Marta Diego, and C. Godoy
An HPTLC method with densitometric detection at 280 nm has been established for quantification of lamotrigine in human serum. Liquid-liquid extraction with ethyl acetate, with chloramphenicol as internal standard, was followed by chromatography on silica gel F254 plates with ethyl acetate-methanol-32% aqueous ammonia 17:2:1 (v/v) as mobile phase. The method was validated for linearity, precision, and accuracy. Calibration plots were linear in the range 0.6 to 300 ng per band, corresponding to 0.06–30.00 ng μL−1 lamotrigine in human serum after extraction and application of 1 μL to the chromatographic plate. The correlation coefficient was 0.998. Intra-assay and inter-assay precision, as relative standard deviation (RSD), were in the range 0.53–2.91% (n = 3) and 1.58–2.98% (n = 9), respectively. The limits of detection and quantification were 0.016 and 0.042 ng, respectively. Accuracy, calculated as percentage recovery, was between 94.09 and 101.30%, with RSD no higher than 3.52%. The method was selective for both lamotrigine and the internal standard. The method enables rapid, precise, accurate, selective, and sensitive quantitative analysis of lamotrigine in human serum.