The invention relates to devices and methods for chemical analysis, specifically to devices for extracting molecules, e.g. biomolecules such as peptides, and/or proteins, from a mixture of molecules in a solution and performing sample treatment on the extracted molecules before presenting them to an analysis instrument. The method for analysis of samples uses a combined sample treatment and sample carrier device. Said device comprises a plate with inlets at one side connected to respective compartments situated at respective array positions for receiving samples to be treated and analysed, each compartment being in communication with an outlet enabling fluid flow through the plate. The method comprises the steps of supplying an external container with a sample; optionally, subjecting the sample to a first treatment in the external container; transferring the sample to the combined sample treatment and sample carrier device; and subjecting the sample to a second treatment exploiting fluid flow through the device, wherein a medium is trapped in the device.