kazakevich - hplc for pharmaceutical scientists (wiley, 2007)

... Applications of LC-NMR, 91620.4 LC-MS-NMR (or LC-NMR-MS or LC-NMR/MS), 91620.4.1 Introduction, 91620.4.2 Modes of Operation for LC-MS-NMR, 91720.4.3 Applications of LC-MS-NMR, 92620.5 Conclusions, ... technologies in-cluding automated high performance liquid chromatography (HPLC) , fast HPLC, automated method development, HPLC- MS (mass spectrometry), HPLC- NMR (nuclear magnetic resonance) and high-throughput ... 07936Li-Kang Zhang, Schering-Plough Research Institute, Kenilworth, NJ 07033xxvi CONTRIBUTORSPART I HPLC THEORY AND PRACTICE HPLC FOR PHARMACEUTICAL SCIENTISTS 1INTRODUCTIONYuri Kazakevich...

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Tài liệu HPLC for Pharmaceutical Scientists 2007 (Part 7A) pptx

... rates are applied. For example, optimum ﬂow rate of 1.0mL/minmay be employed for a 4.6-mm-i.d. column. A 2.1-mm-i.d. column hasoptimum ﬂow rate of 0.2 mL/min. For LC/ESI-MS, ESI-MS is compatible ... excellent tools for structural characterization of complex molecules.A third type of MS/MS instruments is a hybrid of tandem-in-space andtandem-in-time devices, including the Q-trap (QQ-2D-linear trap) ... trap) [45] and theion trap-FT-ICR (2D-linear ion trap-FT-ICR) [46]. The Q-trap takes the con-ﬁguration of triple quadrupole, with the third quadrupole replaced by a 2D-linear ion trap. The uniqueness...

Tài liệu HPLC for Pharmaceutical Scientists 2007 (Part 7B) pptx

... atoms in a structure can provide additional information for struc-tural characterization, such as the differentiation between N- or S-oxide for- mation and hydroxylation in drug metabolism studies. ... calibration can provide an order-of-magnitude greatermass accuracy than external calibration for the FT-MS analysis.One example is the high-resolution ESI-FT-ICR MS analysis of a mixture of ... 14.9 for all con-centrations. The assay performance data suggested the mean overall extrac-tion recovery of ET-743 from human control plasma was between 98.8 ± 10.5%(n = 3) [103].7.7.3.2 On-Line...

Tài liệu HPLC for Pharmaceutical Scientists 2007 (Part 8A) ppt

... (Figure 8-2 ). [2].TYPES OF METHODS 349Figure 8-1 . Synthesis of TMP. (Reprinted from reference 1, with permission.)Impurity 1 and Impurity 2, were identiﬁed as 2,4-diamino- 5-( -4 -ethoxy-3,5-dimethoxybenzyl) ... 2,4-diamino- 5-( -4 -ethoxy-3,5-dimethoxybenzyl) pyrimidine and 2,4-diamino- 5-( 3-bromo-4, 5- dimethoxybenzyl) pyrimidine, respectively (structures shown in Figure 8-3 ),using LC/MS, MS/MS, and NMR. Both these synthetic by-products were presumed ... Trimethoprim (TMP) ( 2-4 -diamino- 5-( 3,4, 5- trimethoxybenzyl)pyrimidine) is an antibacterial, folic acid antagonist that isusually used with sulfamethoxazole as a treatment for urinary tract infections.Shown...

Tài liệu HPLC for Pharmaceutical Scientists 2007 (Part 8B) pdf

... screening can be per-formed. For method column screening, generally columns with 10-cm or 5-cm× 3.0-mm i.d. could be used that are packed with 3- m particles. Implementa-tion of a column switcher ... the respective ana-lytical method that is applied to a real in-process sample or a dosage form for subsequent HPLC analysis. The analytical procedure must specify the manu-facturer, type of ... lot-to-lot reproducibility). The criteria for selec-tion may include that the column is stable for a certain number of columnvolumes (efﬁciency, tailing factor, retention time criteria for...

Tài liệu HPLC for Pharmaceutical Scientists 2007 (Part 8C) pdf

... shorter columns for gradient scoutingexperiments (5 cm × 4.6mm ) packed with 3- m columns or use a high-pressure system (max pressure 15,000 psi) with 10-cm × 2.1-mm, 1. 7- m parti-cles. Use 35–45°C ... ionized form or use a 25 mM ammonium hydroxide buffer(pH 10.5) or 25 mM N-methyl pyrrolidine buffer (pH 10.5) to analyze in itsneutral form. Use a 10-cm × 3.0-mm column packed with 3- m particles ... theseparation performed on a polar end-capped column, Synergy-Hydro-RP(Phenomenex, Torrance, CA). Similar trends in the retention dependence rel-ative to wwpH were observed for all impurities...

Tài liệu HPLC for Pharmaceutical Scientists 2007 (Part 8D) pdf

... were conducted on a 1 5- × 4.6-mm, 3- m column.However, the pH scouting analysis could have been performed faster. A 5-cm× 4.6-mm column on a conventional low-pressure HPLC system could havebeen ... 5-cm or 10-cm × 2.1-mm column, packed with 1. 7- m particles,could have been used in conjunction with an ultrahigh-pressure HPLC system,allowing for further reduction of the analysis time for ... out with these two LC-MS-compatible mobile phases: 10 mM ammonium acetate solution (Figure 8-4 0A)and 10 mM ammonium bicarbonate (Figure 8-4 0B) with the same gradient con-ditions and no changes...

Tài liệu HPLC for Pharmaceutical Scientists 2007 (Part 8E) docx

... canΠΠrLrLrr23024630460425.....-i.d.column-i.d.column-i.d.column2-i.d.column2==METHOD DEVELOPMENT APPROACHES 425be performed for further structural elucidation of the impurities. Deuteratedexperiments can be performed ... synthetic by-product elucidation. Take, for example, the two compounds 5-aminoindazole and 1-aminoindan, both ofwhich have an [M + H]+of 133.9. An HPLC method was developed to sepa-rate these ... rate, what would be the equivalent ﬂow rate for a 15-cm × 3- mm column? Using the following equation, this can be calculated.( 8-2 )If you divide the 1.5-mL/min ﬂow rate by 0.425, then a ﬂow rate...

Tài liệu HPLC for Pharmaceutical Scientists 2007 (Part 8F) docx

... DEVELOPMENTFigure 8-6 4. Separation of synthetic tocopherols by reversed-phase HPLC (280 nm).(1) δ-tocopherol, (2) γ-tocopherol, (3) β-tocopherol, (4) α-tocopherol, (5) α-tocopherylacetate. ... band dis-tortion of the peaks in the chromatogram. Columns packed with 5- m parti-cles typically use 2- m porosity inlet frits to contain the packing; for the 3- mparticles, 0. 5- or 2- m porosity ... less troublesome when mobile phases are ﬁltered. For HPLC applica-tions, the 0. 2- m-pore-size ﬁlter is typically selected for removal of particu-440 METHOD DEVELOPMENTlates that may arise from...

Tài liệu HPLC for Pharmaceutical Scientists 2007 (Part 1) docx

... interactions employedin normal-phase HPLC (see Chapter 5).2. Dispersive forces are employed in reversed-phase HPLC (see Chapter 4).3. Ionic forces are employed in ion-exchange HPLC (see Chapter 4,Section ... stronger interaction inreversed-phase HPLC) , which are insoluble in polar or aqueous solvents.Figure 1-5 demonstrates the application of normal-phase HPLC for the sepa-ration of a mixture of different ... and typical application areas of eachof the above-mentioned HPLC modes is given below.1.6.1 Normal-Phase Chromatography (NP HPLC) Normal-phase HPLC explores the differences in the strength of...

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