Abstract: The present invention is directed to methods for quantitatively measuring biomolecules by using magnetic nanoparticles. Through the use of the magnetic nanoparticles and the bioprobes coated to the magnetic nanoparticles, the biomolecules conjugated with the bioprobes result in the formation of particle clusters. By measuring the changes in magnetic properties resulting from the existence of the bio-targets, the amount of the bio-targets in a sample to be tested can be measured.

Abstract: A superconductive quantum interference device (SQUID) system is provided for measuring the alternating current (AC) magnetic susceptibility of material at a single frequency or a mixing frequency from multiple frequencies, such as mf1+nf2, where f1 and f2 are two excitation frequencies of two primary coils. The system includes a magnetic-flux sourcing unit for producing an AC magnetic flux on a sample and a magnetic-flux reading unit for reading the induced magnetic flux from the sample via a magnetic flux transformer. The magnetic-flux reading unit includes a SQUID set for detecting the induced magnetic flux, so as to obtain the magnetic susceptibility of the sample in converting calculation.

Abstract: A superconductive quantum interference device (SQUID) system is provided for measuring the alternating current (AC) magnetic susceptibility of material at a single frequency or a mixing frequency from multiple frequencies, such as mf1+nf2, where f1 and f2 are two excitation frequencies of two primary coils. The system includes a magnetic-flux sourcing unit for producing an AC magnetic flux on a sample and a magnetic-flux reading unit for reading the induced magnetic flux from the sample via a magnetic flux transformer. The magnetic-flux reading unit includes a SQUID set for detecting the induced magnetic flux, so as to obtain the magnetic susceptibility of the sample in converting calculation.

Abstract: A composition for magnetofecting genetic materials into cells with the assistant of an external magnetic force is described. The composition includes hydrophilic vectors, magnetic nanoparticles, and genetic materials, wherein the magnetic nanoparticles and the genetic materials are enveloped inside the hydrophilic vectors.

Abstract: The present invention is directed to methods for quantitatively measuring biomolecules by using magnetic nanoparticles. Through the use of the magnetic nanoparticles and the bioprobes coated to the magnetic nanoparticles, the biomolecules conjugated with the bioprobes result in the formation of particle clusters. By measuring the changes in magnetic properties resulting from the existence of the bio-targets, the amount of the bio-targets in a sample to be tested can be measured.

Abstract: The present invention is designed as the diagnostic methods using magnetic nanoparticles to quantitatively measure the ligands or biomolecules for assessing/evaluating the status or risks of diseases, such as atherosclerosis, infection/inflammatory diseases, and tumors. Through the use of the magnetic nanoparticles and the bio-receptors coated to the magnetic nanoparticles, the ligands conjugated with the bio-receptors can be detected or marked, and the amount of the ligands in a sample can be determined by measuring the changes in magnetic properties resulting from the existence of the ligands.

Abstract: A method for designing and tuning a refractive index of a magnetic fluid is performed by adjusting some characteristic parameters. The characteristic parameters include the type of carrier, the type of magnetic particles, the concentration of the magnetic ingredient; the wavelength of an intended light onto the magnetic fluid layer; the strength of applied magnetic field; the sweep rate of the magnetic field; the direction of the applied magnetic field; the strength of applied magnetic field associated with the thickness of the magnetic fluid layer; and the strength of applied magnetic field associated with the temperature. A magnetic fluid with a designed value of refractive index under zero magnetic field is synthesized by carefully selecting the carrier and the volume concentration of the magnetic particles, and this value can further be tuning around the designed value by changing the forgoing characteristic parameters.

Abstract: A method for designing and tuning a refractive index of a magnetic fluid is performed by adjusting some characteristic parameters. The characteristic parameters include the type of carrier, the type of magnetic particles, the concentration of the magnetic ingredient; the wavelength of an intended light onto the magnetic fluid layer; the strength of applied magnetic field; the sweep rate of the magnetic field; the direction of the applied magnetic field; the strength of applied magnetic field associated with the thickness of the magnetic fluid layer; and the strength of applied magnetic field associated with the temperature. A magnetic fluid with a designed value of refractive index under zero magnetic field is synthesized by carefully selecting the carrier and the volume concentration of the magnetic particles, and this value can further be tuning around the designed value by changing the forgoing characteristic parameters.

Abstract: Methods for preparing homogeneous magnetic fluid compositions capable of forming ordered one dimensional structures or two dimensional lattices in response to externally applied magnetic fields are disclosed. The compositions are prepared using improved co-precipitation methods in which the steps of the procedure have been tuned to reduce sample heterogeneity. Fe.sub.3 O.sub.4 or MnFe.sub.2 O.sub.4 particles are coated with a surfactant and dispersed in a continuous carrier phase to form these homogeneous magnetic fluid compositions. The ability of these compositions to generate ordered structures can be tested by holding a magnet near a thin film of the compositions and observing the formation of colors in the region near the magnet. Methods for controlling the characteristic spacing of the ordered structures formed by the composition also are disclosed.

Abstract: Methods for preparing homogeneous magnetic fluid compositions capable of forming ordered one dimensional structures or two dimensional lattices in response to externally applied magnetic fields are disclosed. The compositions are prepared using improved co-precipitation methods in which the steps of the procedure have been tuned to reduce sample heterogeneity. Fe.sub.3 O.sub.4 particles are coated with a surfactant and dispersed in a continuous carrier phase to form these homogeneous magnetic fluid compositions. The ability of these compositions to generate ordered structures can be tested by holding a magnet near a thin film of the compositions and observing the formation of colors in the region near the magnet. Methods for controlling the characteristic spacing of the ordered structures formed by the composition also are disclosed.

Abstract: Methods for preparing homogeneous magnetic fluid compositions capable of forming ordered one dimensional structures or two dimensional lattices in response to externally applied magnetic fields are disclosed. The compositions are prepared using improved co-precipitation methods in which the steps of the procedure have been tuned to reduce sample heterogeneity. Fe.sub.3 O.sub.4 particles are coated with a surfactant and dispersed in a continuous carrier phase to form a homogeneous magnetic fluid composition. The ability of the composition to generate ordered structures can be tested by holding a magnet near a thin film of the compositions and observing the formation of colors in the region near the magnet. Methods for controlling the characteristic spacing of the ordered structures formed by the composition are also disclosed.