Abstract: A method comprises loading a sample portion into a sample chamber which comprises means for minimizing diffusion of the sample portion, subjecting the sample portion to an amplification step, and determining whether the sample portion contains at least one molecule of a target nucleic acid. If the sample portion contains a single molecule of the target nucleic acid, the sample portion would attain a detectable concentration of the target nucleic acid after a single round of amplification. Also, a microfluidic device comprising a sample portion and a sample chamber comprising means for minimizing diffusion of the sample portion. Also, a microfluidic device comprising a sample chamber and an amplification targeting reagent positioned in the first sample chamber.

Abstract: A method comprising for each individual sample of a plurality of samples, loading at least one sample portion of the individual sample into at least one respective sample chamber of a plurality of sample chambers, subjecting the sample portions to at least a first amplification step; and then determining whether sample portions contain at least one molecule of the target nucleic acid. For each sample portion, if the sample portion contains at least a single molecule of the target nucleic acid, the sample portion would attain a detectable concentration of the target nucleic acid after a single round of amplification.

Abstract: A method comprising depositing a sample portion in a sample retaining means, and forcing a curable fluid across an exposed surface of the sample retaining means, thereby displacing excess first sample from the exposed surface without displacing the sample from the sample retaining means. Also, a method comprising depositing a sample portion in a sample retaining means, removing excess sample from an exposed surface of the sample retaining means, and depositing a curable fluid on the exposed surface. Also, a microfluidic device comprising a sample chamber, a first sample portion in the sample chamber, and a curable fluid and/or a cured fluid positioned on an exposed surface of a sample retaining means.

Abstract: A microfluidic device comprising a first surface portion and a first sample retaining element, which have differing affinities to a fluid, and a method comprising supplying a sample to such a device. In some embodiments, the differing affinity is a result of plasma, ion embedding, surface charging, chemical, optical, electronic and/or electromagnetic treatment. Also, a microfluidic device comprising at least one microcapillary device having a sample retaining element, at least one surface of which exhibits hydrophobicity, hydrophilicity, electromagnetic force exertion and electrostatic force exertion. Also, a microfluidic device comprising a first element having a hydrophilic pattern comprising at least a first sample retaining element. Also, a method comprising supplying a sample to a channel between a first element and a second element, and inducing in the first element at least one hydrophilic pattern by electrets or by internal or external electrodes to provide a charged surface.

Abstract: A method comprises loading one or more sample portions into respective sample chambers, subjecting each of the sample portions to an amplification step, for each sample portion, determining whether the sample portion contains at least one molecule of a target nucleic acid; and then quantifying a number of the sample portions which contain at least one molecule of the target nucleic acid, and/or quantifying a number of peaks indicative of the detectable concentration, and/or detecting an intensity of at least one peak indicative of a concentration of the target nucleic acid. Any of the sample portions which contains a single molecule of the target nucleic acid would attain a detectable concentration of the target nucleic acid after a single round of amplification.

Abstract: A method comprising loading a sample portion into a sample chamber inside a microcapillary device, subjecting the sample portion to at least a first amplification step, and then determining whether the first sample portion contains at least one molecule of a target nucleic acid. Also, a microfluidic device comprising a sample chamber inside a microcapillary device, and a sample portion and/or an amplification targeting reagent in the sample chamber. Also, a microfluidic assembly comprising a microcapillary device having a sample chamber containing a reagent which enables amplification of a target nucleic acid. Also, a microfluidic device comprising a microcapillary device having a sample retaining means which contains a sample portion and/or an amplification targeting reagent.

Abstract: A microfluidic device comprising a first sample chamber and a first sample portion positioned in the first sample chamber. If the first sample portion contains a single molecule of a target nucleic acid, the first sample portion would attain a detectable concentration of the target nucleic acid after a single round of amplification. Also, a microfluidic device comprising a first sample chamber and at least one amplification targeting reagent positioned in the first sample chamber. If a sample portion which comprises at least a single molecule of a target nucleic acid is positioned in the first sample chamber, the sample portion would attain a detectable concentration of the target nucleic acid after a single round of amplification.

Abstract: A method comprising subjecting one or more sample portion(s) to a single amplification step, thereby amplifying a single molecule in the sample portion to a detectable level, and, in some embodiments, then determining whether the sample portion contains at least one molecule of the target nucleic acid. In some embodiments, the sample portion is in a porous sample structure, or in a sample chamber which comprises means for minimizing diffusion of the sample portion, or in a sample chamber which is inside a microcapillary device, or in a sample retaining means.

Abstract: A method comprises loading a sample portion into a first porous structure, subjecting the sample portion to an amplification step, and determining whether the sample portion contains at least one molecule of a target nucleic acid. If the sample portion contains a single molecule of the target nucleic acid, the sample portion would attain a detectable concentration of the target nucleic acid after a single round of amplification. Also, a microfluidic device comprising a porous sample structure and a sample portion positioned in the porous sample structure. Also, a microfluidic device comprising a porous sample structure and an amplification targeting reagent positioned in the porous sample structure.

Abstract: A method comprising loading sample into at least two sample chambers, subjecting the sample portions in each sample chamber to at least a first amplification step, and determining whether each sample portion contains at least one molecule of a target nucleic acid. If a sample portion contains at least a single molecule of the target nucleic acid, it would attain a detectable concentration of the target nucleic acid after a single round of amplification. Also, a method for detecting whether at least one molecule of a first target nucleic acid is present in a first sample and detecting whether at least one molecule of a second target nucleic acid is present in a second sample. Also, a microfluidic device comprising sample chambers comprising respective ingredients which will react with respective target nucleic acids if contacted with the target nucleic acids and subjected to a round of amplification.

Abstract: A method comprising loading a sample into a microfluidic device which comprises plural sample chambers, subdividing the sample into a plurality of sample portions, such that respective sample portions are positioned in each of a plurality of the sample chambers, and subjecting the sample portions loaded into the respective sample chambers to at least a first amplification step. Each of the sample chambers has a respective volume such that if a sample portion positioned in the sample chamber comprises at least one molecule of a target nucleic acid, the target nucleic acid would attain a detectable concentration in the sample chamber after a single round of amplification.