Efficacy of coating activated carbon with milk proteins to prevent binding of bacterial cells from foods for PCR detection

Abstract

Foods contaminated with pathogens are common sources of illness. Currently, the most common and sensitive rapid detection method involves the PCR. However, food matrices are complex and contain inhibitors that limit the sensitivity of the PCR. The use of coated activated carbon can effectively facilitate the removal of PCR inhibitors without binding targeted bacterial cells from food samples. With the use of activated carbon coated with milk proteins, a cell recovery at pH 7.0 of 95.7%±2.0% was obtained, compared to control uncoated activated carbon, which yielded a cell recovery of only 1.1%±0.8%. In addition, the milk protein coated activated carbon was able to absorb similar amounts of soluble compounds as uncoated activated carbon, with the exception of bovine hemoglobin. This suggests that the use of milk proteins to coat activated carbon may therefore serve as a suitable replacement for bentonite in the coating of activated carbon, which has previously been used for the removal of PCR inhibitors from food.

Keywords: ABS; Activated carbon; Cell recovery; MP-CAC; Milk proteins; PBS; PCR inhibitors; Salmonella; TSA(+); TSB(+); acetate-buffered saline; dH(2)O; deionized water; milk protein coated activated carbon; phosphate-buffered saline; tryptic Soy Agar supplemented with 0.5% glucose; tryptic Soy Broth supplemented with 0.5% glucose.