Figure 10 UV spectrum of FBS before and after adsorption by MTCFs@SIP@CBMA and MTCFs@NIP@CBMA (a); SDS-PAGE analysis of adsorption for BSA by MTCFs@SIP@CBMA from FBS (b). Lane 1: marker; lane 2: FBS stock solution; lane 3: remaining FBS solution after adsorption by MTCFs@SIP@CBMA; lane 4: remaining FBS solution after adsorption by MTCFs@NIP@CBMA; lane 5: the eluent from MTCFs@SIP@CBMA; The dosage of protein solution was 10 μL.
Reusability of MTCFs@SIP@CBMA
Reusability played a very important role for the popularization and application of imprinted materials. In this section, after adsorbing BSA with the same MTCFs@SIP@CBMA and MTCFs@NIP@CBMA, the adsorbed template BSA was eluted with 6% HAc. The adsorption-desorption process was repeated eight times and the adsorption amount was measured each time. As shown in Figure 11a, the adsorption capacity of MTCFs@SIP@CBMA on BSA only lost 4.76% after eight cycles. This loss was caused by the incomplete template elution and the destruction of the imprinting sites due to repeated elution processes. Compared with MTCFs@SIP@CBMA, due to the absence of imprinting sites on MTCFs@NIP@CBMA, the effect of the elution procedure on its adsorption capacity was negligible. Moreover, the morphology of MTCFs@SIP@CBMA after eight cycles of recycling was observed. The SEM and TEM photos are shown in Figure 11b and c. It can be seen that MTCFs@SIP@CBMA maintained a good hollow tubular structure. The VSM curve of MTCFs@SIP@CBMA after eight repeated cycles is shown in Figure 11d. It was observed that the repeated elution process hardly had effect on the magnetic properties of MTCFs@SIP@CBMA. The specific saturation magnetization after eight uses was 6.11 emu/g. Based on the above analysis results, MTCFs@SIP@CBMA possessed excellent reusability, which provided a possibility for further application expansion.