Carbon dots are rapidly emerging carbon-based nanomaterials that, due to their growing applications, will inevitable find their way to natural waters; however, their environmental fate is mostly unknown. Carbon dots with different surface functionality were fabricated and characterized by TEM and FT-IR. Their surface charge, given by the zeta potential, and their hydrodynamic diameter in suspen...

Delivery of therapeutic or diagnostic agents to the brain is majorly hindered by the blood-brain barrier (BBB). Recently, many studies have demonstrated local and transient disruption of the BBB using low power ultrasound sonication combined with intravascular microbubbles. However, BBB opening and closure mechanisms are poorly understood, especially the maximum gap that may be safely generated...

Tapping mode (TM) atomic force microscopy (AFM) in a liquid environment is widely used to measure the contours of biological specimens. The TM triggers the AFM probe approximately at the resonant frequencies and controls the tip such that it periodically touches the specimen along the scanning path. The AFM probe and its tip produce a hydrodynamic pressure on the probe itself and press the spec...

Blood is a complex biological fluid composed of deformable cells and platelets suspended in plasma, a protein-rich liquid. The peculiar nature of blood needs to be considered when designing a drug delivery strategy based on systemically administered carriers. Here, we report on an in vitro fluid dynamic investigation of the influence of the microcapillary flow of red blood cells (RBCs) on micro...

A framework of analogy between wiretap channels (WTCs) and state-dependent point-to-point channels with noncausal encoder channel state information (referred to as Gelfand-Pinker channels (GPCs)) is proposed. A good (reliable and secure) sequence of wiretap codes is shown to induce a good (reliable) sequence of codes for a corresponding GPC. Consequently, the framework enables exploiting existi...

A new system for the generation of hydrodynamic modulated voltammetry (HMV) is presented. This system consists of an oscillating jet produced through the mechanical vibration of a large diaphragm. The structure of the cell is such that a relatively small vibration is transferred to a large fluid flow at the jet outlet. Positioning of an electrode (Pt, 0.5 mm or 25 μm diameter) over the exit of ...

Using dual-focus fluorescence correlation spectroscopy, we have analyzed the adsorption of three human blood serum proteins, namely serum albumin, apolipoprotein A-I and apolipoprotein E4, onto polymer-coated, fluorescently labeled FePt nanoparticles (~12 nm diameter) carrying negatively charged carboxyl groups on their surface. For all three proteins, a step-wise increase in hydrodynamic radiu...

Hydrodynamic and colloidal interactions are explored in concentrated, charge-stabilized colloidal dispersions by measuring the dependence of rheology (e.g., low and high-shear viscosity, high-frequency viscosity, and modulus) and self-diffusivity on salt content, particle size, and concentration. Model, sulfonated polystyrene lactices of varying diameter are prepared and investigated by shear r...

Current advances in single cell sequencing, gene expression and proteomics require the isolation of single cells, frequently from a very small source population. In this work we describe the design and characterization of a manually operated microfluidic cell sorter that 1) can accurately sort single or small groups of cells from very small cell populations with minimal losses, 2) that is easy ...

Fuel-free nanomotors are essential for future in-vivo biomedical transport and drug-delivery applications. Herein, the first example of directed delivery of drug-loaded magnetic polymeric particles using magnetically driven flexible nanoswimmers is described. It is demonstrated that flexible magnetic nickel-silver nanoswimmers (5-6 μm in length and 200 nm in diameter) are able to transport micr...