A Separation Study of Tricyclic Antidepressant Drugs by HPLC with β-Cyclodextrin Bonded Stationary Phase

Distinctive Supramolecular Features of β-Cyclodextrin Inclusion Complexes with Antidepressants Protriptyline and Maprotiline: A Comprehensive Structural Investigation

“…In attempts to search for TCA drugs whose side effects have been relieved by the β-CD encapsulation and their structural components are different from most TCAs, we come across the inclusion complexes of PRT and MPL, which are on the opposite side of the β-CD–TCA stability spectrum. The former is most stable [ 20 , 21 ], while the latter is least stable [ 20 ], based on the binding constants derived in solution. We envisage that the complex stability distinction is due to the -CH=CH- bridge in PRT and the -CH 2 –CH 2 - flexure in MPL, which are the most different structure portions compared to other TCAs; see Scheme 1 and Figure 1 .…”

“…In our research project on a comprehensive structural investigation of the β-CD–TCA inclusion complexes, although the TCA chemical structures are highly similar, their associations with β-CD differ in detail for both host and guest molecules from one complex to another. In particular, the most stable β-CD–PRT [ 21 ] and the least stable β-CD–MPL [ 20 ], it is noteworthy to what extent host β-CD and guest PRT, MPL molecules are changed structurally upon inclusion complexation to comply the induced-fit principle [ 42 ]. This has been addressed below and in Section 2.1 above.…”

“…Both PRT and MPL are less flexible due to the -CH=CH- group bridging both wings and the -CH 2 –CH 2 - flexure across the central 6-membered C-ring, respectively ( Scheme 1 ). Overall comparison among the 2° amine TCA complexes ( Table 1 ), the β-CD–PRT complex is the most stable with K a s of (14.2–24.0) × 10 3 M −1 [ 19 , 20 , 21 ], whereas the β-CD–MPL complex is the least stable with K a s of (4.8–4.9) × 10 3 M −1 [ 19 , 20 ]. This suggests that the β-CD complexation stabilities are strengthened by the presence of PRT -CH=CH- bridge and weaken by the existence of MPL -CH 2 –CH 2 - flexure.…”

Determination of the enantiomer and positional isomer impurities in atomoxetine hydrochloride with liquid chromatography using polysaccharide chiral stationary phases

“…Normal or reversedphase LC separations can be developed by evaluating solvent systems, chromatographic columns, aqueous buffer systems where appropriate, mobile phase pH, and/or temperature. Another option is to examine a more orthogonal chromatographic approach [16,17] which may include chiral chromatography either in reversed or normal-phase mode and using either a chiral mobile phase additive (CMPA) [18] or a CSP [19][20][21][22][23]. Furthermore, an orthogonal analytical technique may also be utilized and positional isomer separations have been reported using capillary electrophoresis (CE) [19,24], capillary electrochromatography [25], supercritical fluid chromatography [26] and gas chromatography [27].…”

Determination of Maprotiline Hydrochloride by Capillary Zone Electrophoresis

“…Maprotiline hydrochloride, 3-(9,10-dihydro-9,10ethanoanthracen-9-yl)-methylpropyl amine hydrochloride is a tetracyclic antidepressant (noradrenaline reuptake inhibitor) with structural similarities to tricyclic antidepressants. Various methods have been proposed for the determination of monoamine oxidase inhibitors and tricyclic antidepressants including gas chromatography (Valsami et al 1992), HPLC (Joron & Robert 1994), HPLC with chemiluminescence detection (Ishida et al 1995), UV-photodiode array detection (Ryan 1993), electrochemical detection (Koyama et al 1993) and b-cyclodextrin-bonded stationary phase (Piperaki et al 1993;Forgacs 1995). Maprotiline and some basic drugs of very similar structure have also been determined by micellar electrokinetic chromatography (Hansen et al 1995) and capillary isotachophoresis (Vlasicova & Polonsky 1994).…”