tailieunhanh - HPLC for Pharmaceutical Scientists 2007 (Part 8E)

422 METHOD DEVELOPMENT Figure 8-47. Resolution map for all critical pairs. Color scale on the left indicates the minimum resolution that is predicted for a particular color in the resolution map. The x axis is the gradient time and the y axis is the temperature. The crosshair can be moved to obtained the predicted conditions for optimal resolution of all critical pairs. See color plate. | 422 METHOD DEVELOPMENT Figure 8-47. Resolution map for all critical pairs. Color scale on the left indicates the minimum resolution that is predicted for a particular color in the resolution map. The x axis is the gradient time and the y axis is the crosshair can be moved to obtained the predicted conditions for optimal resolution of all critical pairs. See color plate. Figure 8-48. Top Drylab-predicted chromatogram versus bottom verification run. METHOD DEVELOPMENT APPROACHES 423 Running Forced Degradation Samples. Prior to initiating method development as was mentioned in Section the structure must be analyzed to predict most probable degradation products. For this compound in this case study it has an amide functionality so most probable impurity is the carboxylic acid impurity. It was indeed determined by a forced degradation study acidic conditions that it was the major acid hydrolysis degradation product. Using the method that was optimized by Drylab a forced degradation sample was run that was stressed at 50 C for 1 week in pH 1 diluent. It was noted that a major impurity was formed Figure 8-49 and was determined to be the carboxylic acid impurity by MS analysis. This compound contains an amide and is prone to hydrolysis. Scheme 2 shows the potential degradation pathway. Therefore to enhance the retention of this potential degradation product the initial organic composition of the gradient was reduced from 35 to 25v v acetonitrile Figure 8-49 . The carboxylic acid impurity has an enhanced retention at lower organic composition and had adequate resolution between active and impurity eluting after main component was still obtained. nh2 . Z I 1 R C R c OH2 R c o H NH. ÎNH R C NH3 XÔ H Scheme 2. Using this optimized method shown in Figure 8-49 that starts at 25v v acetonitrile LC-MS studies were performed to determine the M H ion of the impurity that has been resolved from the main peak. The mass spectrum of Product M was taken and .

• Y học thường thức
• method development
• HPLC
• Pharmaceutical Scientists 2007
• HPLC Theory
• tài liệu chuyên ngành dược
• sách học dược sĩ
• A first course in the finite element method
• The finite element method
• Introduction to the stiffness method
• Development of truss equations
• Development of beam equations
• The plane stress
• Analysis of economic development of Ukraine regions based on taxonomy method
• Analysis of economic development
• Efficiency of further activities
• Regional economic development level
• Vietnam Journal of Science and Technology
• Development of spectrophotometric method
• Development of spectrophotometric method for determination of ceftazidime
• Marshall reagent in pharmaceutical preparation
• Bratton Marshall reagent
• Human development
• Lecture Human development
• Studying development
• Methods for studying development
• Scientific method
• Developmental studies
• The stiffness method
• Grid equations
• From quality supervision method
• Supervision method
• Quality guaranty principles
• The development
• Intergration of Vietnam education
• Higher education
• Lecture Finite element method
• Finite element method
• Bài giảng Phương pháp phần tử hữu hạn
• Transformation of vectors in two dimensions
• Solution of plane truss
• Beam stiffness
• Distributed loading
• Development of quality index method
• Quality index method
• Black tiger shrimp
• The remaining shelf life
• A quality index method
• Development of multivariate calibration method
• Multivariate calibration method
• Simultaneous determination of nickel
• Zinc in tap water
• Partial least squares
• Development and validation of a simple spectrophotometric method
• A simple spectrophotometric method
• Quantification of chloride in polymeric materials
• The dissolution of the polymer
• Vietnam Journal of Chemistry
• Development of spectrophotometric method for determination
• Mesalazine in pharmaceutical preparation
• Spectrophotometric method for determination
• Pentasa and Sunmesacol
• Common excipients present
• The development of coastal village owned enterprises
• Independent village development
• Village Owned Enterprises
• The method of analysis of Strengths
• Essential oil
• Geographical origin
• Isotope ratio
• The development of the GC MS
• The GC MS analytical method
• The isotope ratio of linalool
• Artificial neural network
• Multiple regression analysis
• Artificial neural networks
• Mixture of ascorbic acid
• Parental experiences
• Home video method
• Infant motor development
• Alberta Infant Motor Scale
• Enabling Pediatric Physical Therapists
• New method development
• Validation for identification
• Quantification of methoxyfenozide insecticide residues
• Methoxyfenozide insecticide residues in grapes
• High performance liquid chromatography
• Summary of analytical chemistry thesis
• Analytical chemistry thesis
• Development the analysis method of stimulators
• Gibberellin and cytokin in vegetables
• J matrix method
• algebraic method
• theoretical calculations
• unsteady flows
• atomic
• rotor stator interactions
• nuclear physics
• Science and technology development
• Extended finite element method
• Simulating the mechanical behavior
• Multiple random holes and inclusions
• Functionally graded material
• The finite element method software
• The abstract of Doctoral dissertation
• Chemometric method
• Molecular absorption spectrum overlapping
• Chemometric method for the simultaneous determination
• Market Vietnam
• Social sciences
• The Blended Socratic Method of Teaching
• Enhance critical thinking skills
• Undergraduate business students
• Socratic method of teaching
• Chiral separation techniques
• Preparative chiral separations
• Glycopeptide chiral stationary phases
• Enantiomeric separations
• Priority setting
• Forestry research project
• Multi criteria method
• Sustainable development
• Areas of research opportunity
• Development of causal model of sustainable hospital supply chain management
• Causal model of sustainable hospital supply chain management
• The intuitionistic fuzzy cognitive map method
• Service supply chain
• Sustainable supply chain management