Abstract: Filter cartridge assemblies and housings are provided and include a tubular housing having an inner wall, an outer wall, a first end, and a second end. The housings include inner walls with shoulders or other radially-inwardly extending flow directors at the intersections of adjacent sections of the tubular body. The assemblies include a plurality of filter media sections within the housing, and each of the plurality of filter media sections preferably has a different filter media composition. One or more of the filter media sections traverses one or more of the shoulders or other radially-inwardly extending flow directors such that the flow directors evenly direct the flow of fluid through the assembly. The assemblies find particular applicability in dialysis systems.

Abstract: Filter cartridge assemblies and housings are provided and include a tubular housing having an inner wall, an outer wall, a first end, and a second end. The housings include inner walls with shoulders or other radially-inwardly extending flow directors at the intersections of adjacent sections of the tubular body. The assemblies include a plurality of filter media sections within the housing, and each of the plurality of filter media sections preferably has a different filter media composition. One or more of the filter media sections traverses one or more of the shoulders or other radially-inwardly extending flow directors such that the flow directors evenly direct the flow of fluid through the assembly. The assemblies find particular applicability in dialysis systems.

Abstract: An improved Schiff's reagent for detection of aldehydes (such as formaldehyde and gluteraldehyde) contains a para-rosaniline compound (such as para-rosaniline hydrochloride), orthophosphoric acid, a bisulfite compound (such as sodium metabisulfite), a phosphate compound (such as sodium orthophosphate monobasic), and water. This reagent provides lower detection levels and faster results than the reagents of the prior art, and is particularly useful in testing the rinse solutions of reusable medical equipment (such as hemodialysis equipment).

Abstract: A process for making particulate substantially water-insoluble magnesium phosphate product and method of use of the product for removing ammonia from aqueous solutions. The particulate magnesium phosphate product acts as a remarkably effective scavenger wherein under equilibrium conditions only about six (6) grams of the product are required to bind the ammonia (more exactly, ammonium ions) liberated from one (1) gram of the urea, a result far superior to traditional zirconium phosphate (ZP) prior art materials which under ideal conditions require about 17 to 20 grams of ZP per gram of urea. The particulate magnesium phosphate product can also be used for the removal of ammonium ions either produced by enzymatic or non-enzymatic hydrolysis of urea or proteins or amino acids or available as NH.sub.4.sup.+ from its native source. The magnesium phosphate product is made by forming a slurry of water and magnesium hydroxide in the presence of a phosphate ion-containing buffer having a pH of about 6.5 to about 8.