A process is described for making acrylic acid from dextrose, which comprises fermenting dextrose; removing solids from the resulting fermentation broth; removing lactic acid from the clarified broth by extraction into an organic solvent; separating out the lactic acid-loaded organic solvent while recycling at least a portion of the remainder back to the fermentation step; reacting the lactic acid with ammonia to provide a dehydration feed comprising ammonium lactate while preferably recycling the organic solvent; carrying out a vapor phase dehydration of the ammonium lactate to produce a crude acrylic acid product; and purifying the crude acrylic acid by distillation followed by melt crystallization, chromatography or both melt crystallization and chromatography.

A method comprising separating a plurality of arsenic species using a mixed mode column and a strong acid. The plurality of arsenic species includes at least one of each of an anionic arsenic species, a cationic arsenic species, a neutral arsenic species, and a zwitterionic arsenic species.

An ion exchange resin for use as a stationary phase in an ion chromatography column. The ion exchange resin has a negatively charged substrate particle, a positively charged polymer layer bound to the negatively charged substrate particle, a linker, and an ion exchange group. The ion exchange group includes a sulfonamide group and an amine, in which the ion exchange group is coupled to the positively charged polymer layer via the linker. When the sulfonamide is in a neutral form, a positively charged amine group provides retention; while when the sulfonamide is in an anionic form, the sulfonamide anion becomes a counter ion to the positively charged amine group, forming a zwitterion that reduces retention at that site. Accordingly, the retention time is able to be controlled by adjusting the mobile phase pH.

An enantioselective zwitterionic ion-exchange material comprising a chiral selector component (SO) comprising at least one cation exchange group and at least one anion exchange group and a carrier, carrying said selector component, wherein the chiral selector component comprises at least one chiral linker moiety to connect said ion exchange groups in a non-macrocyclic fashion, and said chiral linker moiety contains at least one - interaction site.

A method of isolating exosomes includes conducting at least one purification step in the presence of an organic zwitterion having a molecular weight of less than about 350 Daltons, a buffering pK of a negatively charged portion of the organic zwitterion is at least one full pH unit below an operating pH at which the at least one purification step is conducted, and a buffering pK of the positively charged portion of the organic zwitterion is at least one full pH unit above the operating pH.

An ion exchange resin for use as a stationary phase in an ion chromatography column. The ion exchange resin has a negatively charged substrate particle, a positively charged polymer layer bound to the negatively charged substrate particle, a linker, and an ion exchange group. The ion exchange group includes a sulfonamide group and an amine, in which the ion exchange group is coupled to the positively charged polymer layer via the linker. When the sulfonamide is in a neutral form, a positively charged amine group provides retention; while when the sulfonamide is in an anionic form, the sulfonamide anion becomes a counter ion to the positively charged amine group, forming a zwitterion that reduces retention at that site. Accordingly, the retention time is able to be controlled by adjusting the mobile phase pH.