Abstract: The present invention relates to a method of purifying peptides and/or polypeptides, said method comprising or consisting of: (a) loading a sample comprising peptides and/or polypeptides under acidic or neutral aqueous conditions on mixed-phase solid phase extraction (SPE) material, wherein said material consists of or comprises reversed phase/ion exchange material; (b) washing said mixed-phase SPE material with (ba) an acidic or neutral composition comprising at least 50% (v/v) organic solvent; and/or (bb) an acidic or neutral aqueous solution; and (c) eluting said peptides and/or polypeptides from said mixed-phase SPE material with an alkaline composition comprising at least 50% (v/v) organic solvent.

Abstract: The present invention relates to a method of purifying peptides and/or polypeptides, said method comprising or consisting of: (a) loading a sample comprising peptides and/or polypeptides under acidic or neutral aqueous conditions on mixed-phase solid phase extraction (SPE) material, wherein said material consists of or comprises reversed phase/ion exchange material; (b) washing said mixed-phase SPE material with (ba) an acidic or neutral composition comprising at least 50% (v/v) organic solvent; and/or (bb) an acidic or neutral aqueous solution; and (c) eluting said peptides and/or polypeptides from said mixed-phase SPE material with an alkaline composition comprising at least 50% (v/v) organic solvent.

Abstract: The present invention relates to a cartridge comprising or consisting of, from top to bottom, the following elements: (a) an inlet; (b) a top volume; (c) at least one optional layer made of a first material; (d) adjacent to (b) or, if present, to (c), at least one layer of chromatographic material; (e) adjacent to (d) at least one layer made of first material; and (f) an outlet; wherein said first material is hydrophobic and porous.

Abstract: The present invention relates to a use of a tertiary amine as buffer in sample preparation, preferably for mass spectrometry and/or UV/vis spectroscopy, wherein the sample comprises proteins, polypeptides and/or peptides, and said sample preparation comprises: (a) protein, polypeptide and peptide denaturation; and (b) chemical isotope labelling and/or chemical cross-linking, wherein said sample preparation does not use primary amine buffers.

Abstract: The present invention relates to a method of purifying peptides and/or polypeptides, said method comprising or consisting of: (a) loading a sample comprising peptides and/or polypeptides under acidic or neutral aqueous conditions on mixed-phase solid phase extraction (SPE) material, wherein said material consists of or comprises reversed phase/ion exchange material; (b) washing said mixed-phase SPE material with (ba) an acidic or neutral composition comprising at least 50% (v/v) organic solvent; and/or (bb) an acidic or neutral aqueous solution; and (c) eluting said peptides and/or polypeptides from said mixed-phase SPE material with an alkaline composition comprising at least 50% (v/v) organic solvent.