Abstract: A microfluidic detection unit comprises at least one fluid injection section, a fluid storage section and a detection section. Each fluid injection section defines a fluid outlet; the fluid storage section is in gas communication with the atmosphere and defines a fluid inlet; the detection section defines a first end in communication with the fluid outlet and a second end in communication with the fluid inlet. A height difference is defined between the fluid outlet and the fluid inlet along the direction of gravity. When a first fluid is injected from the at least one fluid injection section, the first fluid is driven by gravity to pass through the detection section and accumulate to form a droplet at the fluid inlet, such that a state of fluid pressure equilibrium of the first fluid is established.

Abstract: A microfluidic detection unit comprises at least one fluid injection section, a fluid storage section and a detection section. Each fluid injection section defines a fluid outlet; the fluid storage section is in gas communication with the atmosphere and defines a fluid inlet; the detection section defines a first end in communication with the fluid outlet and a second end in communication with the fluid inlet. A height difference is defined between the fluid outlet and the fluid inlet along the direction of gravity. When a first fluid is injected from the at least one fluid injection section, the first fluid is driven by gravity to pass through the detection section and accumulate to form a droplet at the fluid inlet, such that a state of fluid pressure equilibrium of the first fluid is established.

Abstract: A method for detecting albumin based on a colorimetric assay and a system thereof are disclosed. Gold nanoparticles are added into the sample preparing device having a sample without spectroscopic tags, wherein the sample without spectroscopic tags is formed as the alkaline solution to avoid the interference substances adhering on the gold nanoparticles. The gold nanoparticles are concentrated by using the microfluidic concentrator with the circular ion exchange membrane by applying an external electric field across two electrodes. The image of the concentrated gold nanoparticles is captured by the image capturing device for measuring the saturation intensities of the image, wherein there is a relation between the saturation intensities and the concentration of the albumin in the sample without spectroscopic tags. The concentration of the albumin of the sample without spectroscopic tags is obtained by the relation and the measured saturation intensities.

Abstract: A method for detecting albumin based on a colorimetric assay and a system thereof are disclosed. Gold nanoparticles are added into the sample preparing device having a sample without spectroscopic tags, wherein the sample without spectroscopic tags is formed as the alkaline solution to avoid the interference substances adhering on the gold nanoparticles. The gold nanoparticles are concentrated by using the microfluidic concentrator with the circular ion exchange membrane by applying an external electric field across two electrodes. The image of the concentrated gold nanoparticles is captured by the image capturing device for measuring the saturation intensities of the image, wherein there is a relation between the saturation intensities and the concentration of the albumin in the sample without spectroscopic tags. The concentration of the albumin of the sample without spectroscopic tags is obtained by the relation and the measured saturation intensities.

Abstract: A method for obtaining the binding kinetic rate constants using fiber optic particle plasmon resonance (FOPPR) sensor, suitable for a test solution with two or more concentrations, which employs the following major steps: providing one FOPPR sensor instrument system, obtaining optical time-resolved signal intensities starting at the initial time to the steady state of the two or more regions, substituting the measured signal intensity values into the formula which is derived by using the pseudo-first order rate equation model. In addition, this method measures the temporal signal intensity evolution under static conditions as the samples are quickly loaded. As a result, unlike the conventional device where the sample is continuously infused, the method is able to measure the association and dissociation rate constants of which the upper bounds are not limited by the sample flow rate.

Abstract: A method for obtaining the binding kinetic rate constants using fiber optic particle plasmon resonance (FOPPR) sensor, suitable for a test solution with two or more concentrations, which employs the following major steps: providing one FOPPR sensor instrument system, obtaining optical time-resolved signal intensities starting at the initial time to the steady state of the two or more regions, substituting the measured signal intensity values into the formula which is derived by using the pseudo-first order rate equation model. In addition, this method measures the temporal signal intensity evolution under static conditions as the samples are quickly loaded. As a result, unlike the conventional device where the sample is continuously infused, the method is able to measure the association and dissociation rate constants of which the upper bounds are not limited by the sample flow rate.

Abstract: A method for estimating binding kinetic rate constants by using a fiber optic particle plasmon resonance (FOPPR) sensor mainly employs the steps of: providing a FOPPR sensor instrument system, obtaining optical signal intensities at an initial time and steady state signal intensities of first and second regions in an intensity versus time graph separately, substituting the measured signal intensity values into a formula derived by using a pseudo-first order rate equation model. According to this method, no fluorophore labeling is required. In addition, this method measures a temporal signal intensity evolution under static conditions as the samples are quickly loaded. As a result, unlike the conventional device where the sample is continuously infused, the method is able to measure binding and decomposition rate constants whose upper limit is not limited by a sample flow rate.