Hexavalent chromium is a heavy metal used in a variety of industrial applications which is highly toxic to humans, animals, plants and microorganisms. Moreover, it is a well-established human carcinogen by the inhalation route of exposure and a possible human carcinogen by the oral route of exposure. Therefore, it should be removed from contaminated waters. Its reduction to trivalent chromium can be beneficial because a more mobile and more toxic chromium species is converted to a less mobile and less toxic form. During the last two decades, there has been important interest in using zero-valent iron (ZVI) as a Cr(VI)-reducing agent. A considerable volume of research has been carried out in order to investigate the mechanism and kinetics of Cr(VI) reduction with ZVI, as well as the influence of various parameters controlling the reduction efficiency. Therefore, the purpose of this review was to provide updated information regarding the developments and innovative approaches in the use of ZVI for the treatment of Cr(VI)-polluted waters.

Hexavalent Chromium Reduction with Zero-Valent Iron (ZVI) in Aquatic Systems

Measurement of caffeine in coffee beans with UV/vis spectrometer

A critical review on the use of modern sophisticated hyphenated tools in the characterization of impurities and degradation products

A forced degradation study is an essential step in the design of a regulatory compliant stability program for both drug substances and products, and was formalized as a regulatory requirement in ICH Guideline Q1A in 1993. It has since been extended to generic drugs. We provide an update on world-wide regulatory requirements. Also, we list all possible benefits of forced degradation studies to assess the stability of drugs and products. We discuss the kind of forced degradation study likely to meet regulatory expectations. We include the knowledge gained from these studies within the Quality by Design paradigm.

Forced degradation studies to assess the stability of drugs and products

In this paper, we illustrate the potential of ultra-high performance liquid chromatography (UHPLC) coupled with hybrid quadrupole time-of-flight mass spectrometry (QTOF MS) for large scale screening of organic contaminants in different types of samples. Thanks to the full-spectrum acquisition at satisfactory sensitivity, it is feasible to apply both (post)-target and non-target approaches for the rapid qualitative screening of organic pollutants in food, biological and environmental samples. Different strategies have been applied and compared in this work. The first approach consists of target screening based on automatically extracting the exact analyte masses with a narrow mass window (±10 mDa). The selection of analytes can be made after MS acquisition as non-specific analyte information is required when injecting the samples. The second, non-targeted approach, consists of a first component detection step followed by the search of the detected components in home-made spectral libraries. In this work, two types of libraries have been evaluated: a theoretical database, including the molecular formula of a large number of pollutants (∼1000), and an empirical mass spectra library which includes a lower number of compounds for which reference standards were available. In all cases the confidence of the identification process was excellent, thanks to the value of information given in QTOF MSE acquisition mode (i.e. simultaneous acquisition of low and high energy TOF MS spectra in a unique run). Both, target and non-target approaches, are complementary and both have advantages and drawbacks. Their application to different types of samples has allowed the detection of diverse organic compounds, for example the mycotoxin fumonisin B1 in food samples, cocaine and several metabolites in human urine, as well as several pesticides, antibiotics and drugs of abuse in urban wastewater.

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Target and non-target screening strategies for organic contaminants, residues and illicit substances in food, environmental and human biological samples by UHPLC-QTOF-MS

A simple, sensitive and economically viable spectrophotometric method for the determination of some Rauwolfia alkaloids (ajmaline, ajmalicine, reserpine and yohimbine-HCl) has been developed. The method involves the oxidation of Rauwolfia alkaloids by iron(III) and subsequent complexation of iron(II) with 1,10-phenanthroline, forming a red-colored complex having the maximum absorbance at 510 nm. The method is applied to the determination of reserpine in tablets of pharmaceutical formulations. The common excipients do not interfere with the proposed method. A statistical comparison of these results with those of a reported method shows good agreement and indicates no significant difference in the precision.

Spectrophotometric determination of Rauwolfia alkaloids: estimation of reserpine in pharmaceuticals.

Spectrophotometric determination of caffeine and theophylline in pure alkaloids and its application in pharmaceutical formulations.

Identification and characterization of degradation products of irbesartan using LC-MS/TOF, MSn, on-line H/D exchange and LC-NMR

Introduction Training surgeons adds time to the duration of procedures and operation lists. This is not accounted for in the finance received to perform the operation by the hospital in the Payment by Results (PbR) system. 1 Purpose of the study To find out: 1.The effect on the duration of a procedure and the number of procedures performed on the list when a trainee is involved. 2.The percentage of orthopaedic cases with trainee involvement. 3.The effect of European working time directive (EWTD) on the trainee involvement in cases from theatre data in 2008 versus logbook data from 2004 – 2008. Methods Data was taken from two different sources. Firstly, the Operating Room Information System (ORMIS) and patient operation notes. The second source was a consultant's logbook comprising 227 primary total knee replacements performed between 2004 and 2008. Results The data produced trends suggesting trainees took longer to perform procedures than consultants. In orthopaedic operations, 92% of cases had trainees present and of these 17% of cases were performed by trainees in 2008. Before the implementation of the EWTD, trainees performed more procedures when compared with current logbook data (38% versus 17% cases). Time taken by a trainee to perform the procedure under direct consultant supervision was significantly higher in comparison to procedures performed by a consultant alone ( P = Discussion & Conclusion Hospitals should be given financial recognition for training. In this debate, we should remain focused on the provision of quality training for the next generation of surgeons.

The effect of trainee involvement on procedure and list times: A statistical analysis with discussion of current issues affecting orthopaedic training in UK.

Archana Sahu

Papers

A critical review on the use of modern sophisticated hyphenated tools in the characterization of impurities and degradation products

Spectrophotometric determination of Rauwolfia alkaloids: estimation of reserpine in pharmaceuticals.

Spectrophotometric determination of caffeine and theophylline in pure alkaloids and its application in pharmaceutical formulations.

Identification and characterization of degradation products of irbesartan using LC-MS/TOF, MSn, on-line H/D exchange and LC-NMR

The effect of trainee involvement on procedure and list times: A statistical analysis with discussion of current issues affecting orthopaedic training in UK.