Migration of silver nanoparticles from plastic materials, with antimicrobial action, destined for food contact.

Five materials with antimicrobial function, by adding silver, were investigated to evaluate total silver concentration in the polymers and migration of silver nanoparticles from the materials in contact with food. The migration test was carried out by contacting plastic material with food simulant. Migration concentrations and average silver particle sizes were determined by mass spectrometry with inductively coupled plasma, performed in single particle mode (spICP-MS). Additionally, silver particles size and shape were characterized by scanning electron microscopy (SEM) with chemical identification by energy-dispersive X-ray spectroscopy (EDS). Most of samples showed detectable total silver concentrations and all samples showed migration of silver nanoparticles, with concentrations found between 0.00433 and 1.35 ng kg-1. Indeed, the migration study indicated the presence of silver nanoparticles in all food simulants, with sizes bellow 95 nm. The average particle size determined for acetic acid was greater than that observed in the other simulants. In the images obtained by SEM/EDS also confirmed the presence of spherical silver nanoparticles, between 17 and 80 nm. The findings reported herein will aid the health area concerning of human health risk assessments, aiming at regulating this type of material from a food safety point of view.

Development of a non-destructive method for determining protein nitrogen in a yellow fever vaccine by near infrared spectroscopy and multivariate calibration.

Near infrared spectroscopy (NIR) with diffuse reflectance associated to multivariate calibration has as main advantage the replacement of the physical separation of interferents by the mathematical separation of their signals, rapidly with no need for reagent consumption, chemical waste production or sample manipulation. Seeking to optimize quality control analyses, this spectroscopic analytical method was shown to be a viable alternative to the classical Kjeldahl method for the determination of protein nitrogen in yellow fever vaccine. The most suitable multivariate calibration was achieved by the partial least squares method (PLS) with multiplicative signal correction (MSC) treatment and data mean centering (MC), using a minimum number of latent variables (LV) equal to 1, with the lower value of the square root of the mean squared prediction error (0.00330) associated with the highest percentage value (91%) of samples. Accuracy ranged 95 to 105% recovery in the 4000-5184 cm-1 region.

Quality evaluation of commercially available male condoms in Rio de Janeiro, Brazil, 2009-2011.

BACKGROUND: The increased incidence of sexually transmitted infections (STIs) in Brazil represents a significant public health issue. This issue has raised awareness among health authorities regarding the quality of condoms. In Brazil, male condoms need to be certified. The certification process evaluates in detail the manufacturing and quality of the final product; however, post-market surveillance is not part of the normal certification practice. METHODS: From 2009 to 2011, we evaluated 20 male condoms brands per lot of 8 manufactures-both domestic and imported-marketed in Rio de Janeiro, Brazil. Sampling was performed per ISO 2859-1, and the condoms were evaluated on length, width, thickness, holes, integrity of primary packaging, bursting volume, bursting pressure, label and secondary packaging, following the criteria established in the Brazilian National Health Oversight Agency Resolution no. RDC 62/2008. RESULTS: Of the 20 evaluated brands, 17 brands were found to be noncompliant with the guidelines of the Brazilian National Health Oversight Agency Resolution no. RDC 62/2008 in at least one of the analyses performed. CONCLUSIONS: Any nonconforming unit has serious public health implications.