One‐Pot Synthesis of Spheres‐on‐Sphere Silica Particles from a Single Precursor for Fast HPLC with Low Back Pressure

Abstract

Spheres-on-sphere (SOS) silica particles are prepared in a one-pot scalable synthesis from mercaptopropyltrimethoxysilane with hydrophilic polymer and cationic surfactant under alkaline conditions. The SOS particles exhibit solid-core porous-shell properties. The fast separation of small molecules and proteins with low back pressure are demonstrated by high-performance liquid chromatography (HPLC) for the columns packed with SOS-particles.

Tuning Morphology of Nanostructured ZIF-8 on Silica Microspheres and Applications in Liquid Chromatography and Dye Degradation

“…During the thermal treatment in air at 550°C, the organic components including the carbon chains and surface functional groups were decomposed to produce inorganic silica. 37 Therefore, the SOS surface functional groups (−COOH, −SH, and −NH 2 ) could not contribute to the degradation performance, although the surface functional groups did impact the ZIF-8 morphology. The SOS-SH@ZIF-8 composite mcirospheres ( Figure 1B) were chosen because of the relatively uniform coating of small ZIF-8 nanocrystals.…”

“…This resulted from the ZIF-8 coating because the as-prepared SOS-SH particles were nonporous. 37 The apparent BET surface area of the composite microspheres was 495 m 2 /g with pore volume of 0.19 mL/g. Total N 2 uptake of 124 mL/g at a relative pressure p/p 0 = 0.95 is 31% of that observed for the pure bulk ZIF-8 (400 mL/g).…”

Core–shell microspheres with porous nanostructured shells for liquid chromatography

“…Recently, a unique type of core−shell particle with large macropores was reported by Ahmed et al. . The particles were prepared by one‐pot synthesis at room temperature from a single precursor 3‐mercaptopropyltrimethoxysilane.…”

“…For the SOS particles, both the nanospheres and microspheres are nearly free of mesopores, although a type I nitrogen isotherm was generated implying the presence of microporosity <1 nm in size after low temperature sintering . Surfactants have minimal contribution in microporosity formation and the microporosity is believed to be mainly from the decomposition of 3‐mercaptopropyltrimethoxysilane during sintering.…”

“…The current core-shell particles preparation method does have its limitation, e.g., poor QC in multiple-step synthesis, time consuming and a large amount of waste, particularly when constructing the particles with thick shell. Recently, a unique type of core−shell particle with large macropores was reported by Ahmed et al [90]. The particles were prepared by one-pot synthesis at room temperature from a single precursor 3-mercaptopropyltrimethoxysilane.…”