Development and Validation of Highly Sensitive LC–ESI-MS/MS Method for Bortezomib and Its Applications for Plasma Levels and Drug Content of Branded and Generic Formulations in India

In the present study, a highly sensitive and reproducible bio-analytical method was developed using LC–ESI-MS/MS to assess the lower plasma levels of bortezomib in multiple myeloma patients. The gradient elution was optimized using reverse-phase C18 column with mobile phases consisting of water and acetonitrile in 0.1% formic acid. Multiple reaction monitoring mode was used for quantification using precursor-to-product ion transition for bortezomib and sulfadiamethoxine was used as internal standard. This method was validated with a linearity range of 0.195–25 ng mL^?1. Intra-day and inter-day accuracy was 99.17–101.89% and 95.01–102.92% with precision of?<?9.87% and?<?8.77%, respectively. Bortezomib was stable in plasma samples stored at ? 80 °C for up to 10 months. The lower limit of quantification was found to be 0.195 ng mL^?1. This method was also found to be capable of quantifying bortezomib trough levels (ranging 0.19–0.7 ng mL^?1) in plasma of multiple myeloma patients post-cycle 1–6. Bortezomib content in the commonly prescribed generic formulations was also studied. The concentration in all formulations was within the 90–110% of the innovator, as prescribed by the USFDA, ruling out their role blood level variation. The study supports the use of this method for trough level estimation and therapeutic drug monitoring of bortezomib in multiple myeloma patients.

     

Solid-state graphene-based supercapacitor with high-density energy storage using ionic liquid gel electrolyte: electrochemical properties and performance in storing solar electricity

Journal of Solid State Electrochemistry - The electrochemical properties and high-density energy storage performance of graphene nano-platelet-based solid-state electrical double-layer...     

Polynomials in operator space theory: matrix ordering and algebraic aspects

We extend the \(\lambda \)-theory of operator spaces given in Defant and Wiesner (J. Funct. Anal. 266(9): 5493–5525, 2014), that generalizes the notion of the projective, Haagerup and Schur tensor norm for operator spaces to matrix ordered spaces and Banach \(*\)-algebras. Given matrix regular operator spaces and operator systems, we introduce cones related to \(\lambda \) for the algebraic operator space tensor product that respect the matricial structure of matrix regular operator spaces and operator systems, respectively. The ideal structure of \(\lambda \)-tensor product of \(C^*\)-algebras has also been discussed.     

Comparison of duality models in fractional linear programming

Summary This paper deals with the duality models in fractional linear programming presented in the last years bySwarup, Kaka, Sharma andSwarup and other authors.

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Zusammenfassung Der Aufsatz befaßt sich mit Dualitätsmodellen für Linear Fractional Programming, die in den letzten Jahren vonSwarup, Kaka, Sharma undSwarup sowie von anderen Autoren angegeben wurden.

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This work was sponsored by the Grant No. A 7329 from the National Research Council of Canada.     

Study of vibrational spectra of polyaniline doped with sulfuric acid and phosphoric acid

Vibrational spectra of insulator emeraldine base (EB) form of polyaniline and electrical conductive sulfuric acid-and phosphoric acid-doped emeraldine salts (ES) were studied in the region of 4000-400 cm⁻¹ at ambient temperature by Fourier transform infrared spectroscopy. Infrared transmittance spectra of EB and ES were investigated to understand the bonding behavior of different organic and inorganic groups present in the polymeric chains and their structural variations on protonation by sulfate or phosphate ion inclusion in the polymer salt network. These studies revealed the para-coupling of deformed disubstituted benzenoid (B) and quinoid (Q) rings with ends capped predominantly by (B4Q1) units. The deformation of B and Q rings was confirmed by the appearance of many weak bands, very weak bands, and satellite structures in strong transmittance peaks of polymeric chain-constituting groups. Protonation takes place at the nitrogen sites of Q rings and forms semiquinone radical ions in ES. The vibrational bands pertaining to B rings, Q rings, B4Q1 units, semiquinone segment, sulfate ions, and phosphate ions were observed and assigned from these measurements. The shift in peak position of some bands with gain or loss in intensity and appearance of some new bands were observed in sulfuric acid-and phosphoric acid-doped ES spectra. These variations are attributed to the formation of new structural groups in ES on protonation and a change in crystalline field by sulfate and phosphate ion doping for crosslinking the polymeric chains.