SynopsisProtection against ultraviolet (UV) radiation is the major function of sunscreen lotions and UV-protective coatings for vehicles, homes, equipment and clothing. Sunscreen formulations have been optimized to become protective over a broader spectrum of UV radiation and maintain greater photostability. They are comprised of organic and inorganic components that act as chemical and physical UV protectors, respectively. Some of the organic components are limited by their spectrum of protection and photostability. Studies using solid lipid nanoparticles, recently explored organic molecules, inorganic components and antioxidants attempt to further optimize UV protection. In this review, we examine traditional and emerging nanoparticle components and highlight novel ideas in UV protection which may provide pathways for future studies. Ré suméLa protection contre les rayons ultraviolets (UV) est la principale fonction des crèmes solaires et des revêtements de protection UV pour les véhicules, les logements, les équipements et les vêtements. Les formulations solaires ont été optimisées pour devenir des protections de large spectre UV et pour maintenir une plus grande photo stabilité. Ils sont composés de matières organiques et inorganiques qui agissent comme des produits de protection respectivement chimique et physique contre les UV. Certains des composants organiques sont limités par leur spectre de protection et leur photo stabilité. Les études récentes de nanoparticules lipidiques solides (SLN) des molécules organiques, inorganiques et antioxydants, ont exploré des voies d'optimisation de protection UV. Dans cette revue, nous examinons les composants traditionnels et les nanoparticules émergentes ainsi que les idées de protection UV pour proposer de futures études.

The separation of target nucleic acid sequences from biological samples has emerged as a significant process in today's diagnostics and detection strategies. In addition to the possible clinical applications, the fundamental understanding of target and sequence specific hybridization on surface modified magnetic beads is of high value. In this paper, we describe a novel microfluidic platform that utilizes a mobile magnetic field in static microfluidic channels, where single stranded DNA (ssDNA) molecules are isolated via nucleic acid hybridization. We first established efficient isolation of biotinylated capture probe (BP) using streptavidin-coated magnetic beads. Subsequently, we investigated the hybridization of target ssDNA with BP bound to beads and explained these hybridization kinetics using a dual-species kinetic model. The number of hybridized target ssDNA molecules was determined to be about 6.5 times less than that of BP on the bead surface, due to steric hindrance effects. The hybridization of target ssDNA with non-complementary BP bound to bead was also examined, and non-specific hybridization was found to be insignificant. Finally, we demonstrated highly efficient capture and isolation of target ssDNA in the presence of non-target ssDNA, where as low as 1% target ssDNA can be detected from mixture. The microfluidic method described in this paper is significantly relevant and is broadly applicable, especially towards point-of-care biological diagnostic platforms that require binding and separation of known target biomolecules, such as RNA, ssDNA, or protein.

The simple method for amplifying RNA targets (SMART) was used to detect K103N, a common HIV-1 reverse transcriptase drug-resistance mutation. Novel amplifiable SMART probes served as reporter molecules for RNA sequences that are captured and separated on a microfluidic platform under zero-flow conditions. Assays were performed both off chip and in a microchip reservoir using a modified version of real-time nucleic acid sequence-based amplification, without the noncyclic phase, and 65°C preheat. A total of 6000 copies/mL of the synthetic sequences were detected within 180 minutes of amplification. Although the sensitivity of research platforms is higher, SMART has the potential to offer comparable sensitivity and speed to commercially available viral load and HIV detection kits. Furthermore, SMART uses an inexpensive, practical, and more accurate isothermal exponential amplification technique. The use of molecular beacons resulted in relatively fast real-time detection (<180 minutes); however, they were also shown to hinder the amplification process when compared with end point detection. Finally, SMART probes were used for modeling of K103N concentrations within an unknown sample. Only 1% of the SMART probes was detected within the wild-type population (6 × 10(8) copies/mL). These results establish the groundwork for point-of-care drug resistance and viral load monitoring in clinical samples, which can revolutionize HIV patient care globally.