Folic acid retention evaluation in preparations with wheat flour and corn submitted to different cooking methods by HPLC/DAD.

Folic acid content was evaluated in food preparations containing wheat and corn flour submitted to baking, deep-frying, and steaming. Commercially fortified flours showed the absence of folic acid. Flours with laboratory folic acid fortification showed 487 and 474 μg of folic acid in 100 g of wheat and corn flours, respectively.

Studies on Toxicity of Suspensions of CdTe Quantum Dots to Biomphalaria glabrata Mollusks.

Quantum dots have generated great interest because of their optical properties, both to life sciences and electronics applications. However, possible risks to the environment associated with these nanoparticles are still under investigation. The present study aimed to evaluate the toxicity of suspensions of cadmium telluride (CdTe) quantum dots to Biomphalaria glabrata mollusks, a very sensitive aquatic environmental bioindicator for physical and chemical agents.

Semiquantitative fluorescence method for bioconjugation analysis.

Quantum dots (QDs) have been used as fluorescent probes in biological and medical fields such as bioimaging, bioanalytical, and immunofluorescence assays. For these applications, it is important to characterize the QD-protein bioconjugates. This chapter provides details on a versatile method to confirm quantum dot-protein conjugation including the required materials and instrumentation in order to perform the step-by-step semiquantitative analysis of the bioconjugation efficiency by using fluorescence plate readings.

Considerations on the quinine actinometry calibration method used in photostability testing of pharmaceuticals.

This paper addresses two critical issues concerning the guidelines adopted by the ICH on the photostability testing: the quinine actinometry method and the light/radiation exposure map distribution of the photostability chamber. Using a qualified non-commercial photostability chamber tests were performed using quinine and physical actinometry and compared the results to those which are used as the basis of the ICH guidelines. The statistical analysis on the results showed that: (i) the calibration curve of the quinine solution depends on its concentration and on its location in the chamber; (ii) the quinine actinometry method currently recommended by the ICH guidelines should not be generalized to any photostability chamber.

Investigation of red blood cell antigens with highly fluorescent and stable semiconductor quantum dots.

We report a new methodology for red blood cell antigen expression determination by a simple labeling procedure employing luminescent semiconductor quantum dots. Highly luminescent and stable core shell cadmium sulfide/cadmium hydroxide colloidal particles are obtained, with a predominant size of 9 nm. The core-shell quantum dots are functionalized with glutaraldehyde and conjugated to a monoclonal anti-A antibody to target antigen-A in red blood cell membranes.