Compositions, devices, and methods are disclosed for the modification of polymer surfaces with coatings having a dispersion of silicone polymer and hydrophobic silica. The surface coatings provide the polymer surface with high hydrophobicity, as well as increased resistance to biofouling with proteinaceous material. The polymer surfaces can be particularly useful in microfluidic devices and methods that involve the contacting of the covalently modified polymer surfaces with emulsions of aqueous droplets containing biological macromolecules within an oil carrier phase.

Fluidic devices and related methods are generally provided. The fluidic devices described herein may be useful, for example, for diagnostic purposes (e.g., detection of the presence of one or more disease causing bacteria in a patient sample). Unlike certain existing fluidic devices for diagnostic purposes, the fluidic devices and methods described herein may be useful for detecting the presence of numerous disease causing bacteria in a patient sample substantially simultaneously (e.g., in parallel). In some embodiments, the fluidic devices and methods described herein provide highly sensitive detection of microbes in relatively large fluidic samples (e.g., between 0.5 mL and about 5 mL), as compared to certain existing fluidic detection (e.g., microfluidic) devices and methods. In an exemplary embodiment, increased detection sensitivity of microbial pathogens present in a patient sample (e.g., blood) is performed by selectively removing human nucleic acid prior to sensitive detection of microbial infection. In some embodiments, the fluidic device allows for the identification of microbial pathogens directly from unprocessed blood without having to conduct blood culturing processes.