Performance Characteristics of Nanoporous Carbon Membranes for Protein Ultrafiltration

Abstract

Nanoporous carbon membranes could be very attractive for applications of ultrafiltration in the biotechnology industry because of their greater mechanical strength and longer membrane life. The objective of this study was to obtain quantitative data on the performance characteristics of nanoporous carbon membranes formed within a stainless steel support that was first modified by deposition of silica particles within the macroporous support. The nanoporous carbon membrane effectively removed small solutes from a protein solution using diafiltration, with performance comparable to that of commercial polymeric membranes. Protein fouling was evident, although the nanoporous carbon membranes were easily regenerated; cleaning with 0.5 N NaOH at 50 degrees C completely restored the water permeability for multiple cycles. The nanoporous carbon membranes were also compatible with steam sterilization. Significant increases in process flux could be obtained using periodic back-pulsing, with no evidence of any structural alterations in the membrane. These results clearly demonstrate the potential benefits and opportunities for using nanoporous carbon membranes for protein ultrafiltration.

Placental Chemokine Receptor D6 Is Functionally Impaired in Pre-Eclampsia

“…Plasma membranes (post-nuclear particulate fraction without cytosolic components) from trophoblast cells were isolated as described elsewhere [31]. Briefly, cell pellet was resuspended in 2,5 ml of ice-cold buffer (250 mM sucrose, 20 mM HEPES, pH 7.4, 2 mM EGTA, 3 mM NaN3) containing freshly added protease inhibitors (200 μM pheylmethylsulphonylfluoride and 1 μM leupeptin; Sigma) and homogenized in a 5ml glass Dounce homogenizer.…”