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Identify all issues

P/S: No need to describe in detail. Just identify the issues

e.g. CS1: (a) peak tailing; (b) ghosting

0.80 0.045 0.60 0.040 a MPA: 0.1% TFA in water MPB: 0.1% TFA in ACN Gradient: 25% -65% B in 15 min Baseline shift = 0.1 AU UV Spectrum Of 0.05 % TFA vs. Water 20.40 0.035 0.030 0.20 0.025 0.00 AU 0.020 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18:00 20:00 22.00 Minutes 0.015 0.010 0.90 b 0.006 MPA: 0.05% TFA in water MPB: 0.03% TFA in ACN Baseline shift -0.002 AU 0.000 0.60 0.40 220.00 240.00 20.00 290.00 300.00 nim 0.20 0.00 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 20.00 22.00 Minutes Figure 10.15. Chromatograms illustrating gradient shift problems at 230 nm encountered during method development of an impurity test method for a drug substance (Section 8.8.2). The UV spectrum of 0.05% TFA vs. water is shown in the inset, showing considerable absorbance at 230nm