Systems and methods for performing reactions in an unsealed environment

An open system for performing a reaction, comprising:

• a support functionalized for linking a biopolymer or biological particle and for performing the reaction, wherein the support comprises a bead, pin, comb, wafer, well or microchip;
• a nanoliter dispensing pipette for dispensing an amount of a liquid onto the surface of the support;
• a temperature controlling device for regulating the temperature of the support;
• and
• means for controlling the amount of liquid dispensed, wherein the amount of liquid dispensed corresponds to the amount of liquid that evaporates from the support, wherein the system is not sealed.

A system, comprising:

• a solid support having a target site for retaining or containing a liquid;
• a liquid dispensing system for dispensing a liquid to the target site;
• a temperature controlling system, which regulates the temperature of the solid support;
• and
• an interface for indicating an amount of liquid to be dispensed to the target site, wherein the amount of liquid to be dispensed corresponds to an amount of liquid that evaporates from the target site, wherein:
• the interface monitors the level of a liquid on the target site;
• and
• the interface comprises a light source and a photometer.

A system, comprising:

• a solid support having a target site for retaining or containing a liquid;
• a liquid dispensing system for dispensing a liquid to the target site;
• a temperature controlling system, which regulates the temperature of the solid support;
• and
• an interface for indicating an amount of liquid to be dispensed to the target site, wherein the amount of liquid to be dispensed corresponds to an amount of liquid that evaporates from the target site, wherein the interface monitors the concentration of a component in the liquid.

A system comprising:

• means for dispensing a liquid;
• means for containing a reaction volume comprising a microchip or glass slide, wherein the microchip or glass slide comprises on a surface, an array of hydrophilic regions and adjacent hydrophobic regions;
• means for controlling the temperature of the reaction volume containing means;
• and
• means for regulating an amount of liquid dispensed from the liquid dispensing means based on the temperature of the reaction volume containing means.

A method for performing a reaction in an unsealed environment, comprising the steps of:

• a) dispensing a predetermined submicroliter volume of liquid onto a target site on a surface of a support;
• b) determining an amount or rate of evaporation of the liquid from the target site;
• and
• c) dispensing a further amount of liquid to the target site, wherein the further amount dispensed corresponds to the amount of liquid that evaporates from the target site, thereby maintaining the reaction volumes and concentration of reactant at a predetermined volume throughout the course of the reaction.

A method for performing a reaction in an unsealed environment, comprising the steps of:

• a) dispensing a predetermined submicroliter volume of liquid onto a target site on a surface of a support;
• b) determining an amount or rate of evaporation of the liquid from the target site, wherein the amount or rate of evaporation is determined by monitoring the conductance of the liquid at the target site;
• and
• c) dispensing a further amount of liquid to the target site, wherein the further amount dispensed corresponds to the amount of liquid that evaporates from the target site, thereby maintaining the reaction volume at a predetermined volume throughout the course of the reaction.

A method for performing a reaction in an unsealed environment, comprising the steps of:

• a) dispensing a predetermined submicroliter volume of liquid onto a target site on a surface of a support;
• b) determining an amount or rate of evaporation of the liquid from the target site;
• and
• c) dispensing a further amount of liquid to the target site, wherein the further amount dispensed corresponds to the amount of liquid that evaporates from the target site, thereby maintaining the reaction volume at a predetermined volume throughout the course of the reaction, wherein the reaction is a nucleic acid amplification reaction.

A method for performing a reaction in an unsealed environment, comprising the steps of:

• a) dispensing a predetermined submicroliter volume of liquid onto a target site on a surface of a support;
• b) determining an amount or rate of evaporation of the liquid from the target site;
• and
• c) dispensing a further amount of liquid to the target site, wherein the further amount dispensed corresponds to the amount of liquid that evaporates from the target site, thereby maintaining the reaction volume at a predetermined volume throughout the course of the reaction, wherein:
• the reaction is one of a plurality of reactions, and
• the plurality of reactions are performed at a single target site.

A method for performing a reaction in an unsealed environment, comprising the steps of:

• a) dispensing a predetermined submicroliter volume of liquid onto a target site on a surface of a support;
• b) determining an amount or rate of evaporation of the liquid from the target site;
• and
• c) dispensing a further amount of liquid to the target site, wherein the further amount dispensed corresponds to the amount of liquid that evaporates from the target site, thereby maintaining the reaction volume at a predetermined volume throughout the course of the reaction, wherein:
• the reaction is one of a plurality of reactions;
• each reaction in the plurality is performed at a single target site;
• and
• the method comprises synthesis of a combinatorial library.

A method for performing a reaction in an unsealed environment, comprising the steps of:

• a) dispensing a predetermined submicroliter volume of liquid onto a target site on a surface of a support;
• b) determining an amount or rate of evaporation of the liquid from the target site;
• and
• c) dispensing a further amount of liquid to the target site, wherein the further amount dispensed corresponds to the amount of liquid that evaporates from the target site, thereby maintaining the reaction volume at a predetermined volume throughout the course of the reaction;
• and
• d) detecting a component of the reaction, detecting a component of the reaction.

A method for performing a plurality of reactions in an unsealed environments, comprising the steps of:

• a) providing a plurality of reaction mixtures, wherein each reaction in the plurality is at a target site on a surface of a solid support;
• b) monitoring the amount of liquid that evaporates from reaction mixtures in the plurality;
• and
• c) dispensing into the reaction mixtures an amount of liquid that corresponds to the amount of liquid that evaporates from the reaction mixtures, thereby maintaining the volume of the reaction mixtures in the plurality at a predetermined volume, wherein one or more of the reaction mixtures in the plurality comprises one or more biopolymers.

A method for performing a plurality of reactions in an unsealed environments, comprising the steps of:

• a) providing a plurality of reaction mixtures, wherein each reaction in the plurality is at a target site on a surface of a solid support;
• b) monitoring the amount of liquid that evaporates from reaction mixtures in the plurality;
• c) dispensing into the reaction mixtures an amount of liquid that corresponds to the amount of liquid that evaporates from the reaction mixtures, thereby maintaining the volume of the reaction mixtures in the plurality at a predetermined volume;
• and
• d) detecting a component of a reaction mixture in the plurality.

A method for performing a plurality of reactions in an unsealed environment, comprising:

• a) providing a plurality of reaction mixtures, wherein each reaction in the plurality is performed at a target site on a surface of a solid support that contains or retains the reaction mixtures;
• b) monitoring the amount of liquid that evaporates from reaction mixtures in the plurality;
• and
• c) dispensing into the reaction mixtures an amount of liquid that corresponds to the amount of liquid that evaporates from the reaction mixtures, thereby maintaining the volume of the reaction mixtures in the plurality at a predetermined volume, whereby the concentrations of reactants in the reaction mixtures remain constant.