Conventional apolar stationary phases

A summary of the Hnear relahonships exishng between log Pod and logk can be found in the supplementary material (see Sechon 13.5). A part of these relationships carmot be used for the prediction of log Pod values due the low range of Hpophihcity covered by the solutes or the weak stahstics resulhng from the low number of solutes measured and their limited chemical diversity. 

Studies of octylsilane (OS) phases, deactivated by end-capping, have shown that such stationary phases lead to a discrimination between compounds according to their H-bond donor capacity, as the stationary phase presents strong accessible H-bond acceptor groups (-Si-O-Si-) [22, 23]. For OS phases with a uniform matrix of cross-Hnked polysiloxane alkyl groups, relatively low correlations between log few and log Poet were found. 

Chemically bonded stahonary phases, e.g. alkylamide silica reversed phases, were also developed. Despite a generally good stability and good quality of resolution and less interachons with free silanol groups, correlahons between log Pod and log kw are relahvely poor compared to a number of other stahonary phases [26]. Finally, monolithic silica stahonary phases have also been applied for Upo-philicity determinahon of a series of P-blockers [27]. 

A soluhon explored to definitely eliminate the problem of interachons with free silanol groups was the use of non-silica based stahonary phases. Many studies recently reviewed [9] were conducted on this class of stahonary phases to test their usefulness for UpophiUcity prediction. A few of these phases including polybutadiene-coated alumina [4] and octadecyl-bonded alumina show intereshng results. Conversely, several of them show poor correlahons or correlahons not better than those obtained on ODS stahonary phases between the retenhon parameter and log Pod- 

Recently, other 1AM stahonary phases based on different types of phospholipids like phosphahdylserine (lAM.PS), phosphahdylethanolamine (1AM.PE) or sphin- 

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