Determination of impurities in insulinlike growth factor with ESMS

ES-MS provides an excellent means for quality control of recombinant proteins, some of which are now used as drugs, e.g. human insulin, interferons, erythropoietin and tissue plasminogen activating factor.1 The advantage of ES-MS in the determination of proteins is that multiple charges can be formed on a protein to bring it within range of standard mass spectrometers which have a mass range of 1000-2000 amu. A protein with a charge of 10+ and a MW of 10 000 would show up at 1000 amu. It would...

Examples of IR spectra of drug molecules

Some examples of interpretations are given in Figures 5.10-5.14 and Tables 5.3-5.6. In the examples only limited interpretation of the fingerprint region is attempted since often assignments in this region are not certain. Even above 1500 cnr' it is sometimes difficult to assign bands thus IR is not a primary structure elucidation technique. The major absorptions which can be observed in drug molecules, stg. strong absorption md. medium absorption wk. weak absorption brd. broad shp. sharp conj....

Titrimetric and chemical analysis methods

Primary standards and standard solutions Direct acid base titrations in the aqueous phase Weak acid strong base and weak base strong acid titrations Indirect titrations in the aqueous phase Estimation of esters by back titration Estimation of alcohols and hydroxyl values by reaction with acetic anhydride AA Iodine-absorbing substances in penicillins Titrations using iodide as a lipophilic anion Use of Potentiometrie titration to determine pKa values Karl Fischer titration coulometric end-point...