Incorporation of Benzalkonium Chloride to Improve the Antimicrobial Properties of Lignocellulosic Material

TEMPO nanofibrillated cellulose (TNFC), carboxymethyl cellulose (CMC), and lignin were applied as nanoscale carrier molecules for benzalkonium chloride (BZK), a well-known organic biocide. The resulting hybrid suspension was analyzed for biocidal activity against Escherichia coli (E. coli) and dried for scanning electron microscopy analysis using a solvent exchange and freeze drying technique. The results indicate that there is slow release of BZK in suspension, which is desirable for long-term antimicrobial activity. Instant biocidal activity can be achieved with a minimal inhibitory concentration of 0.116 M BZK-TNFC hybrid suspension. Lignin and CMC used in complex with BZK to create a 0.046 M BZK-Lignin and 0.046 M BZK-CMC suspension demonstrated increased antimicrobial activity with longer exposure times. Initial concentrations of E. coli were 3.1 x 10^-6 and 0.5 x 10^-6, while 24 hour exposure at 37° C resulted in complete inhibition of bacteria.