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Cetuximab is a chimeric IgG1 monoclonal antibody that inhibits epidermal growth factor receptor (EGFR). Additionally, Cetuximab, used in combination therapy, potentiates the effects of chemotherapy and radiation therapy in eradicating well-established tumors. Recently, a combination of Cetuximab and newly developed chemotherapeutic candidate drugs is being investigated for use as a new-generation chemotherapy cocktail. Therefore, there is an increasing need for a highly selective immunoassay to detect Cetuximab at low concentration levels in human serum. We report a newly developed ELISA that is validated under FDA-GLP regulations for the detection of Cetuximab. It is highly selective and achieves a lower limit of quantitation of 0.31 µg/mL. We have validated a selective and sensitive bioanalytical method.

Prostate cancer is impacting many men globally. It is a disease that has no effective treatment is available in the market. The understanding of the biophysical and biochemical aspects of the disease and the mechanism that allow it to metastasize is key to finding an effect treatment. Maintenance or pretreatment drug as well as a post treatment drug can be effective to avoid or delay the disease from appearing. The polysaccharides and monosaccharides polymers combined with vitamins can be the ingredient to developing the treatment. There are many evidences that investigators examined the individual components of the therapy proposed but never a combination of all these therapies. The one item that is not discussed is how to formulate the ingredient into an effective form which is a proprietary work being conducted currently. Nevertheless, the hypothesis seems reasonable to us and worth sharing with the scientific community.

The 8th GCC Closed Forum for Bioanalysis was held in Baltimore, MD, USA on 5 December 2013, immediately following the 2013 AAPS Workshop (Crystal City V): Quantitative Bioanalytical Methods Validation and Implementation – The 2013 Revised FDA Guidance. This GCC meeting was organized to discuss the contents of the draft revised FDA Guidance on bioanalytical method validation that was published in September 2013 and consolidate the feedback of the GCC members. In attendance were 63 senior-level participants, from seven countries, representing 46 bioanalytical CRO companies/sites. This event represented a unique opportunity for CRO bioanalytical experts to share their opinions and concerns regarding the draft FDA Guidance, and to build unified comments to be provided to the FDA.

Ionic conductors are solids that have a large number of defects and easy pathways that make it possible for ions to move over long distances in an electric field. In order to be mobile an ion must be small and have a low charge. The fluoride ion is the most mobile anion. The highest performance fluoride ion conductors contain divalent tin, and have a highly layered crystal structure related to the CaF2 fluorite type. BaSnF4 has the α-PbSnF4 structure, which is a √2√2 × √2√2 × √2 superstructure of the fluorite type, where the tetragonal unit-cell and the value of the a and b parameters being equal to half the diagonals of the (a, b) face of fluorite are due to the loss of the F Bravais lattice, and the Sn Sn Ba Ba order along the c parameter is at the origin of the doubling of the c parameter. The BaSnF4 material was prepared first by Denes et al. (C. R. Acad. Paris C, 280: 831, 1975), and its superionic properties were characterized by Denes et al. (Solid State Ion., 13: 213, 1984). It was found to have a conductivity three orders of magnitude higher than that of BaF2, with an ionic conduction rate τi>0.99. No BaSnF4 was obtained by the aqueous medium, when aqueous solutions of SnF2 and Ba(NO3)2 are mixed together; BaSn2F6 was obtained instead. In a new development of this work, BaSnF4 has been obtained by the wet method for the first time. X-ray powder diffraction showed that the BaSnF4 phase obtained by the wet method varies substantially from one sample to another: (a) signification variations of the c parameter of the tetragonal unit-cell reveals that the interlayer distance is sensitive to the leaching conditions, possibly because some of the leached ions remain in the interlayer spacing; (b) large variations of the crystallite dimensions and, as a result of the two-dimensionality of the structure, a strong crystallite dimension anisotropy are observed, with d‖d⊥, where d‖ and d⊥ are the crystallite dimensions parallel to the four-fold main axis, and perpendicular to it, respectively, showing that the layers are very thin and the interlayer interactions are very weak. Variable temperature Mossbauer spectroscopy showed an unusual large variation of the quadrupole splitting with temperature. A tentative explanation based on unusually large bond angles has been proposed.

A flow-injection biosensor-like system based on a nonenzymatic approach has been developed to determine the carbamate pesticide carbaryl in complex biological samples without lengthy and expensive extraction steps. Molecularly imprinted polymeric beads were used to immobilize carbaryl from biological samples. pH variation permitted the elution of carbaryl from the binding cavity to the flow cell. A pH electrode was used to detect changes in the charge of carbaryl in the sample solution resulting from the protonation and deprotonation of the molecule over different pH ranges. At pH 2.0, the secondary amine group is protonated, giving a (+1) charge to the carbaryl molecule. At pH 8.0, the ionized carbaryl loses a proton to become neutral, changing the local pH of the flow cell. The pH change at the flow cell generated by the deprotonation of carbaryl ion in alkaline medium was used to determine the carbaryl concentration. Parameters influencing the performance of the system were optimized for use in the detection procedure. The validated biosensor-like system had a carbaryl detection limit of 10.0 μg/mL and a response that was linear (r 2 > 0.98) over the concentration range of 10.0–00 μg/mL.

A carbaryl and 1-naphtol molecular imprinted polymers (MIP1 and MIP 2, respectively) were prepared using suspension polymerization and tested for selective and reversible binding to carbaryl and 1-naphtol, respectively. In the suspension polymerization technique used, polymers of methacrylic acid (MAA), highly cross-linked with ethylene dimethacrylate, provide a specific binding sites for the carbaryl molecule and its metabolite when using it as a template to be removed after polymerization. The molecular imprinted polymer with a particle size of approximately 5 microm were isolated and packed into a pre-column (50 mm x 4.6 mm id) that was used to isolate carbaryl and its metabolite from complex matrices injected on a high performance liquid chromatography system using ultra-violet detection without extensive sample preparation and clean up. The HPLC method had a detection limit of 1.00 ng/mL and a linear response (r2 > 0.98) over the concentration range of 1.00-10.0 ng/mL.