Kevin K. Han

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In human brain extracts, most proteins of pathological interest in Alzheimer's disease are insoluble and their analysis is often performed on denatured and reduced samples by immunoblotting after electrophoresis on polyacrylamide gel in presence of sodium dodecyl sulfate. Because we needed to accurately compare the concentration of several proteins in brain(More)
We present an optofluidic sensor based on an elastomeric two-dimensional (2D) grating integrated inside a hemispherical fluid chamber. A laser beam is diffracted before (reflection) and after (transmission) going through the grating and liquid in the dome chamber. The sensing mechanism is investigated and simulated with a finite-difference time-domain-based(More)
We have implemented a multifunctional optofluidic sensor that can monitor changes in the refractive index and pressure of biofluid simultaneously and can detect free-solution molecular interaction in situ. In this Letter, we demonstrate two major improvements of this sensor proven by both simulation and experiments. One improvement is the broader(More)
Wafer-scale nano-mushroom sensor was demonstrated with the refractive index sensitivity of 373 nm/RIU, resulting in significant color shift detectable by eye. It also works for surface-enhanced Raman spectroscopy with the enhancement factor of 10<sup>7</sup>.
Tau proteins are the major components of Paired Helical Filaments (PHF) of Alzheimer's disease. Using the immunoblot technique and an antiserum against PHF, we have studied the distribution of Tau proteins in the different areas of normal human brains and Alzheimer brains. Tau proteins were clearly present in cortical grey matter but were difficult to(More)
The Pseudo-peptide (pGlu-His-Dopamine) was subjected to enzymatic degradation by porcine serum and brain homogenate. The digests were quantitatively analyzed by HPLC to provide evidence for liberation of pyroglutamic acid and dopamine in serum and of pyroglutamic acid in brain. The yield of liberation of pGlu is about 3% in serum digests and about 0.70% in(More)
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