A novel polyhedral oligomeric silsesquioxane (POSS)-containing aptamer-modified hybrid affinity monolith with excellent hydrophilicity and unique architecture without Si–OH groups is presented herein, and the nonspecific adsorption caused by the hydrophobic nature of the monolithic column or polar interaction with silanol groups is minimized. Via a simple “one-pot” procedure, hydrophilic monomers were facilely polymerized with the POSS-methacryl substituted (POSS-MA) and aptamer; a highly hydrophilic nature was obtained and the lowest contact angle of 11° was achieved. By using ochratoxin A (OTA) as the model analyte, highly selective recognition of OTA in the mixture was achieved and the control of nonspecific interactions and the cross-reactivity of OTB and AFB1 were significantly improved. The recovery yield of OTB caused by nonspecific adsorption in the resultant monolith was only about 0.1% and remained steady even with the coexistence of a high OTB content (OTA : OTB = 1 : 50), which reached the best level to date and was obviously less than the 6.1% occurring in the hydrophobic POSS-containing control monolith, 8.3% in the POSS-PEI@AuNPs@aptamer affinity monolith and 18.7% in the silica-hybrid affinity monolith. When applied to wine and wheat samples, the nonspecific adsorption was significantly reduced and efficient discrimination of OTA was obtained with better results than that of the hydrophobic POSS-containing affinity column. This provides an attractive tool for minimizing the nonspecific adsorption for highly selective on-column recognition.
Yanan Sun,Hengzhi You,Chengyang Hong,Feng Ge,Hao Liu
This study investigates the influence of chain length on the crystalline structure and thermodynamic behavior of side-chain polyhedral oligomeric silsesquioxane (POSS)-containing homopolymers. A series of precisely synthesized POSS-containing polymers with exact chain lengths was prepared using precision chemistry. Comprehensive characterization revealed that the covalent attachment of crystalline POSS cages to the polymer backbone confined their crystallization to a 2D lattice, fundamentally distinct from the chain-folding mechanism of conventional polymers. Polarized optical microscopy confirmed the absence of birefringence during crystallization, consistent with this constrained geometry. Differential scanning calorimetry demonstrated that the melting temperature systematically increased with longer chain lengths, attributed to reduced configurational entropy in the molten state, but remained invariant with isothermal crystallization temperature for each sample. Crystal structure analysis confirmed identical interlamellar spacing and crystalline packing across different chain lengths, supporting a model where POSS cages form crystalline bilayers sandwiching the incompatible polyester backbone layer. These findings provide robust experimental validation for the 2D lattice crystallization model in POSS-containing polymers and establish precise molecular design as a key strategy for tailoring the hierarchical organization and thermal properties of hybrid nanocomposites.
危险品化学品经营许可证（带存储）