Six citrate phosphate dextrose (CPD)-saline adenine glucose mannitol (SAG M) quadruple systems were evaluated for the preparation and storage of leukocyte-poor platelet concentrates (PC) from buffy coats. The platelet storage bags examined were manufactured from normal polyvinylchloride (PVC) or special-type plastics. Biotest supplied PVC 76 (n = 14) and PVC 763 (n = 16) NPBI supplied PSV 3277 (n = 15) and DPL-110 (n = 14) and Terumo supplied Teruflex (n = 18) and molded Teruflex (n = 14). The PC were stored for 7 days at 22 degrees C on a horizontally shaking platform. Cell counts, pH, PO2, PCO2, morphology score and swirling patterns were monitored at 5, 72, 120 and 168 h. The plasma volumes averaged 63 ml and ranged from 39 to 81 ml, the overall mean +/- SD platelet concentration was 0.89 +/- 0.33 X 10(9)/ml. None of the PC had a leukoyte count higher than 10 X 10(6) per unit. After storage for 168 h, the pH ranged from 6.56 to 7.40 for all brands. The PO2 remained stable and even rose significantly (p less than 0.05) during storage in the NPBI PSV 3277 and Terumo molded Teruflex bags. The PCO2 decreased equally in all bags. Morphology scores were well maintained in 98% of all PC for up to 120 h, and in 83% at 168 h. A swirling pattern score of 2.5 or greater predicted with a specificity of 100% a good morphology score in the PC.(ABSTRACT TRUNCATED AT 250 WORDS)