Methods and devices for performing chemical reactions under controlled temperatures are described. In one embodiment, the devices provided by the invention comprise a housing dimensioned to hold a reaction chamber disposed within an interior volume of the housing. The reaction chamber has thermally conductive interior and exterior surfaces defining an internal volume therein at a first temperature. The device also includes at least one thermally conductive temperature-control bladder disposed therein, which bladder is configured to receive a temperature-control substance at a second temperature into said bladder and expel said temperature-control substance from said bladder. The bladder is further configured such that upon receiving the temperature-control substance, the bladder expands to abut substantially at least a portion of said exterior surfaces of said reaction chamber to enable thermal exchange between said temperature-control substance the said internal volume of reaction chamber.