The invention is in the field of regulation of enzymatic activity in nucleic acid modifying reactions. It describes a method of regulating enzymatic activity by adding chelating agents to the reaction composition and exploits the fact that both the binding of divalent cations to these chelating agents and the pH of commonly used buffers is temperature dependent. PCR experiments that are hampered by non-specific side products can be regulated such that the target sequence is amplified in a more specific manner.

This application provides fluidic devices, such as microfluidic devices, which can be used for the creation and/or manipulation of droplets in droplet-based microfluidic systems, as well as systems and methods for using the same. The microfluidic devices can be used to generate droplets, extract or inject volume to droplets, and/or split droplets. Also provided are methods for generating nucleosomes, and isolated DNA from nucleosomes (or from non-nucleosomes), for example using the disclosed devices.

This application provides fluidic devices, such as microfluidic devices, which can be used for the creation and/or manipulation of droplets in droplet-based microfluidic systems, as well as systems and methods for using the same. The microfluidic devices can be used to generate droplets, extract or inject volume to droplets, and/or split droplets. Also provided are methods for generating nucleosomes, and isolated DNA from nucleosomes (or from non-nucleosomes), for example using the disclosed devices.

Provided is a method for producing a cell contained base, the method being capable of providing a cell contained base highly accurately controlled in number of nucleic acid molecules contained in a low-concentration nucleic acid standard sample, the method including a liquid droplet discharging step of discharging a cell suspension in the form of a liquid droplet with a liquid droplet discharging unit onto a base including at least one cell contained region; a cell number counting step of counting a number of cells contained in the liquid droplet with a plurality of sensors from two or more directions while the liquid droplet is flying into the cell contained region; and a liquid droplet landing step of landing the liquid droplet in the at least one cell contained region in a manner that a predetermined number of cells are located in the at least one cell contained region.

Provided is a method for producing a cell contained base, the method being capable of providing a cell contained base highly accurately controlled in number of nucleic acid molecules contained in a low-concentration nucleic acid standard sample, the method including a liquid droplet discharging step of discharging a cell suspension in the form of a liquid droplet with a liquid droplet discharging unit onto a base including at least one cell contained region; a cell number counting step of counting a number of cells contained in the liquid droplet with a plurality of sensors from two or more directions while the liquid droplet is flying into the cell contained region; and a liquid droplet landing step of landing the liquid droplet in the at least one cell contained region in a manner that a predetermined number of cells are located in the at least one cell contained region.

The present invention discloses a convective PCR apparatus by using a transparent conductive thin film to replace the traditional metal heater. The PCR reaction is activated when the container with reagents contacted the heated transparent conductive thin film and the temperature inside the container raised to initiate the convective circulation. Also, the present invention could apply for a quantitative PCR reaction by adding a specific probe, a fluorescent dye, a light source, or a photon receiver.

The present invention discloses a convective PCR apparatus by using a transparent conductive thin film to replace the traditional metal heater. The PCR reaction is activated when the container with reagents contacted the heated transparent conductive thin film and the temperature inside the container raised to initiate the convective circulation. Also, the present invention could apply for a quantitative PCR reaction by adding a specific probe, a fluorescent dye, a light source, or a photon receiver.

Devices, systems, and their methods of use, for generating droplets are provided. One or more geometric parameters of a microfluidic channel can be selected to generate droplets of a desired and predictable droplet size.

A minimal-copy-ratio of templates is a problem in detecting early stage cancer where minimal copies of somatic cancer-specific mutations are targeted in the presence of large copies of wildtype genome DNA, commonly a 1/10,000 or even less minimal-copy-ratios between the mutant target and wildtype control templates. To overcome this problem, delayed pyrophosphorolysis activated polymerization (delayed-PAP) was developed which can delay product accumulation of the wildtype control to a much later time or cycle, such as by 15 cycles or by 30,000 folds. In the multiplex format, delayed-PAP is particularly useful to amplify not only the wildtype control but also mutant target templates accurately and consistently in the minimal-copy-ratio situation.

A minimal-copy-ratio of templates is a problem in detecting early stage cancer where minimal copies of somatic cancer-specific mutations are targeted in the presence of large copies of wildtype genome DNA, commonly a 1/10,000 or even less minimal-copy-ratios between the mutant target and wildtype control templates. To overcome this problem, delayed pyrophosphorolysis activated polymerization (delayed-PAP) was developed which can delay product accumulation of the wildtype control to a much later time or cycle, such as by 15 cycles or by 30,000 folds. In the multiplex format, delayed-PAP is particularly useful to amplify not only the wildtype control but also mutant target templates accurately and consistently in the minimal-copy-ratio situation.