Flow rate dependent extra-column variance from injection in capillary liquid chromatography

Core–Shell, Ultrasmall Particles, Monoliths, and Other Support Materials in High-Performance Liquid Chromatography

“…Zou and coworkers studied the photoinitiated thiol-yne click reaction of 1,7-octadiyne with 1,6-hexanedithiol or pentaerythritol tetrakis(3-mercaptopropionate) (PTM) 161 164 , and higher performance of monoliths with greater extent of crosslinking was shown, the net column efficiency was not very high. The positive effect of hypercrosslinking on column efficiency and permeability was also shown by Urban 165 .…”

“…163 Column efficiency, H = ∼15 μm for a small alkylbenzene at u = 0.3−0.4 mm/s in 70/30 = acetonitrile/water, and slightly larger H for unretained uracil were reported with K = 0.63−0.82 × 10 −14 m 2 for the TRIM monolith. Although correction for extra-column band broadening was included 164 and higher performance of monoliths with greater extent of cross-linking was shown, the net column efficiency was not very high. The positive effect of hypercross-linking on column efficiency and permeability was also shown by Urban.…”

Numerical investigation of band spreading generated by flow-through needle and fixed loop sample injectors

“…Whereas these analytically obtainable inj-values relate to a few well-defined injection peak shapes, it should be noted these shapes are seldom observed in practice. Experimental values for 4 1/inj reported in literature cover a very broad span of values, ranging from 0.125 to 50 [7,9,10,[12][13][14][18][19][20][21][22] . This wide variation can in part be explained by the fact that the distinction between 𝜎 𝑉,𝑖𝑛𝑗,𝑣𝑜𝑙 2 and 𝜎 𝑉,𝑖𝑛𝑗 2 is not always made and because different types of injectors (full loop, partial loop or flow-through needle injector) were considered.…”

Current trends in the development of porous polymer monoliths for the separation of small molecules

“…different instrumentation) may skew resulting efficiency, especially on instrumentation where extra‐column contribution is not optimized. When extra‐column volumes are minimized, column efficiency improves significantly .…”