Articles by Uihan Kim in JoVE
A Rapid and Chemical-free Hemoglobin Assay with Photothermal Angular Light Scattering Uihan Kim1, Jaewoo Song2, Suho Ryu1, Soocheol Kim1, Chulmin Joo1 1School of Mechanical Engineering, Yonsei University, 2Department of Laboratory Medicine, Yonsei University A photo-thermal angular light scattering (PT-AS) sensor enables the rapid and chemical-free hemoglobin assay of nanoliter-scale blood samples. Here, details of the PT-AS setup and a measurement protocol for the hemoglobin concentration in blood are provided. Representative results for anemic blood samples are also presented.
Other articles by Uihan Kim on PubMed
Capillary-scale Direct Measurement of Hemoglobin Concentration of Erythrocytes Using Photothermal Angular Light Scattering Biosensors & Bioelectronics. Dec, 2015 | Pubmed ID: 26176206 We present a direct, rapid and chemical-free detection method for hemoglobin concentration ([Hb]), based on photothermal angular light scattering. The iron oxides contained in hemoglobin molecules exhibit high absorption of 532-nm light and generate heat under the illumination of 532-nm light, which subsequently alters the refractive index of blood. We measured this photothermal change in refractive index by employing angular light scattering spectroscopy with the goal of quantifying [Hb] in blood samples. Highly sensitive [Hb] measurement of blood samples was performed by monitoring the shifts in angularly dispersed scattering patterns from the blood-loaded microcapillary tubes. Our system measured [Hb] over the range of 0.35-17.9 g/dL with a detection limit of ~0.12 g/dL. Our sensor was characterized by excellent correlation with a reference hematology analyzer (r>0.96), and yielded a precision of 0.63 g/dL for a blood sample of 9.0 g/dL.
Color-coded LED Microscopy for Multi-contrast and Quantitative Phase-gradient Imaging Biomedical Optics Express. Dec, 2015 | Pubmed ID: 26713205 We present a multi-contrast microscope based on color-coded illumination and computation. A programmable three-color light-emitting diode (LED) array illuminates a specimen, in which each color corresponds to a different illumination angle. A single color image sensor records light transmitted through the specimen, and images at each color channel are then separated and utilized to obtain bright-field, dark-field, and differential phase contrast (DPC) images simultaneously. Quantitative phase imaging is also achieved based on DPC images acquired with two different LED illumination patterns. The multi-contrast and quantitative phase imaging capabilities of our method are demonstrated by presenting images of various transparent biological samples.