Price: £193.00. Add to Cart. Add to Wish List Add to Compare. ASPEC ALUMINA-A, 200 mg, 3 mL caps, 50/Box. SKU: 54350768. Acidic ASPEC® Alumina solid phase extraction (SPE) cartridges contain a high-quality, polar sorbent used in the same way as ASPEC® Silica but with a better pH stabililty (range of 4.0 – 5.5).