Cyano bonded silica monolith—Development of an in situ modification method for analytical scale columns

The Retention Characteristics of a Novel Phenyl Analytical Scale First Generation Monolith

“…Comparable to a phenyl endcapped particle packed column efficiency of 34,000 N=m. [7] However, were substantially lower than a C18 endcapped modified monolith (73,000 N=m), [1] a cyano endcapped modified phase (82,000 N=m), [3] and a commercial C18 endcapped monolith (60,000 N=m). [43] The lower plate count demonstrates that different ligands employed do not bind similarly to the silica monolithic scaffold, when employing the same in situ modification method.…”

“…The data in Table 2 also includes S coefficients measured on a variety of different surface density, propyl phenyl endcapped particle packed columns, [7] and a cyano endcapped monolith taken from prior work. [3] The methylene selectivity for the phenyl modified monolith (non-endcapped) displayed excellent linearity (R 2 value of 0.9992). For the endcapped phenyl modified monolith surface a polynomial best fit the results (R 2 value of 0.9997), this effect has not been observed on particle packed columns.…”

“…[43] The lower plate count demonstrates that different ligands employed do not bind similarly to the silica monolithic scaffold, when employing the same in situ modification method. [1,3] A phenyl analytical scale silica monolith does not exist for comparison.…”

“…The in situ modification method by our group has proven to successfully bond a chosen selectivity onto the surface of a commercial bare silica analytical scale monolith, without losing the integrity of the monolithic bed. [1][2][3] The in situ modification method's trimethylsilylation endcapping approach was maintained in this study, [1][2][3] as it has proven successful to reduce peak tailing. [4] It has been established that phenyl type stationary phases provide a unique selectivity and surface chemistry to alkyl phases for reversed phase high performance liquid chromatography (RP-HPLC).…”

“…[1][2][3]5,7,17,20] Retention selectivity regarding the methylene and phenyl group is studied by a set of alkylbenzenes and linear polycyclic aromatic hydrocarbons (PAHs) by plotting S vs. n (where n represents the nth member of the homologous series). Linearity in these relationships should be observed, increasing in a consistent manner with the increase of n. Discontinuity in these plots means a loss of resolution or convergence of the LSS relationships.…”