The Drainage Error in Measurements of Viscosity by the Capillary Tube Method

Spontaneous emergence of chirality is a pervasive theme in soft matter. We report a transient twist forming in achiral nematic liquid crystals confined to a capillary tube with square cross...

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Capillary Effect Enhancement in a Plastic Capillary Tube by Nanostructured Surface

Polymers ◽

10.3390/polym13040628 ◽

2021 ◽

Vol 13 (4) ◽

pp. 628

Author(s):

Kazuma Kurihara ◽

Ryohei Hokari ◽

Naoki Takada

Keyword(s):

Plasma Treatment ◽

Capillary Tube ◽

Capillary Effect ◽

Nanostructured Surface ◽

Nanostructure Fabrication ◽

Wetting Properties ◽

Treatment Processes ◽

Standard Solution ◽

The Cost ◽

Plastic Surfaces

We investigated the enhancement of the capillary effect in a plastic capillary tube using only a nanostructured surface. Since plastic is a hydrophobic material, the capillary effect does not emerge without an additional coating or plasma treatment process. Therefore, capillary effect enhancement by the nanostructure fabrication method is expected to reduce the cost and minimise the contamination produced in the human body. By combining a hydrophilic nylon resin and a nanostructure at the tip of the plastic pipette, we could confirm that the capillary effect was produced solely by the tube fabrication process. The produced capillary effect increased linearly with increasing nanostructure height when a standard solution with a surface tension of 70 mN·m−1 was used. Thus, we can conclude that including the plastic part with nanostructure can be useful for biomedical applications. In addition, we suggest that the proposed method is highly effective in controlling the wetting properties of plastic surfaces, compared to the typical coating or plasma treatment processes.

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Remote, Long-Pathlength Cell for High-Sensitivity Raman Spectroscopy

Applied Spectroscopy ◽

10.1366/0003702874868089 ◽

1987 ◽

Vol 41 (1) ◽

pp. 126-130 ◽

Cited By ~ 60

Author(s):

Scott D. Schwab ◽

Richard L. McCreery

Keyword(s):

Fiber Optics ◽

Laser Light ◽

Capillary Tube ◽

High Sensitivity ◽

Sample Tube ◽

Increased Sensitivity ◽

Sampling Systems ◽

Power Densities ◽

Objective Being ◽

Focused Beam

Fiber optics were used to interface a Raman spectrometer to a long (1 m) sample tube, with the objective being increased sensitivity. Internal reflection of the laser light and the Raman scatter within the sample tube permitted a long solution length to be sampled, increasing the Raman sensitivity by factors of 30–50 over conventional capillary tube sampling systems. In addition, the sample was subjected to much lower power densities than with systems employing a focused beam, thus minimizing radiation damage. Detection limits of 10−9 to 10−8 M were achieved for resonance Raman scatterers, and normal Raman scatterers could be detected at the 1 × 10−5 M level.

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Gold Nanoparticles Affect Pericyte Biology and Capillary Tube Formation

Pharmaceutics ◽

10.3390/pharmaceutics13050738 ◽

2021 ◽

Vol 13 (5) ◽

pp. 738

Author(s):

Sasikarn Looprasertkul ◽

Amornpun Sereemaspun ◽

Nakarin Kitkumthorn ◽

Kanidta Sooklert ◽

Tewarit Sarachana ◽

...

Keyword(s):

Gold Nanoparticles ◽

Endothelial Cell ◽

Mrna Expression ◽

Capillary Tube ◽

Quantitative Polymerase Chain Reaction ◽

Tube Formation ◽

Endothelial Cell Proliferation ◽

Control Group ◽

Capillary Tubes ◽

Cell Functions

Gold nanoparticles (AuNPs) are used for diagnostic and therapeutic purposes, especially antiangiogenesis, which are accomplished via inhibition of endothelial cell proliferation, migration, and tube formation. However, no research has been performed on the effects of AuNPs in pericytes, which play vital roles in endothelial cell functions and capillary tube formation during physiological and pathological processes. Therefore, the effects of AuNPs on the morphology and functions of pericytes need to be elucidated. This study treated human placental pericytes in monoculture with 20 nm AuNPs at a concentration of 30 ppm. Ki-67 and platelet-derived growth factor receptor-β (PDGFR-β) mRNA expression was measured using real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Cell migration was assessed by Transwell migration assay. The fine structures of pericytes were observed by transmission electron microscopy. In addition, 30 ppm AuNP-treated pericytes and intact human umbilical vein endothelial cells were cocultured on Matrigel to form three-dimensional (3D) capillary tubes. The results demonstrated that AuNPs significantly inhibited proliferation, reduced PDGFR-β mRNA expression, and decreased migration in pericytes. Ultrastructural analysis of pericytes revealed AuNPs in late endosomes, autolysosomes, and mitochondria. Remarkably, many mitochondria were swollen or damaged. Additionally, capillary tube formation was reduced. We found that numerous pericytes on 3D capillary tubes were round and did not extend their processes along the tubes, which resulted in more incomplete tube formation in the treatment group compared with the control group. In summary, AuNPs can affect pericyte proliferation, PDGFR-β mRNA expression, migration, morphology, and capillary tube formation. The findings highlight the possible application of AuNPs in pericyte-targeted therapy for antiangiogenesis.

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