Serum-separating tube Serum-separating tube Serum-separating tubes, also known as serum separator tubes or SSTs, are used in medical clinical chemistry tests requiring blood serum. SSTs are sometimes called "marble-top tubes," "tiger-tops," or "gold-topped tubes", referring to the stoppers which are either gold, red with a gold ring on top, or marbled red and grey. Marble-top tubes are also referred to as "tiger-tops" in some clinics. SPS tubes have a paler colour, sometimes leading confusion; these are known as "yellow tops" not "gold". Trademarked versions include Covidien "Corvac" tubes. They contain a special gel that separates blood cells from serum, as well as
Blood, Sweat & Tears pursue a solo career. He was briefly replaced by Bobby Doyle and then Jerry Fisher, who went on to front the next incarnation of Blood, Sweat & Tears. Fred Lipsius left as well and was briefly replaced by Joe Henderson, before Lou Marini settled into the new lineup. Another founding member, Dick Halligan, also departed, replaced by jazz pianist Larry Willis (from the Cannonball Adderley Quintet), and Swedish guitarist Georg Wadenius, from the popular Swedish outfit Made in Sweden, joined as lead guitarist around the same time. The new edition of Blood, Sweat & Tears released "New Blood" in September