Why Should You Overlay the gel? What Should You Use for an Overlay? Regarding Reproducible Polymerization, What Practices Will Ensure That Your Bands Run the Same Way Every Time? What Is the Importance of Reagent Purity on Protein..343 What Catalyst Concentration Should You Use? Electrophoresis and Staining Which Gel Should You Use? SDS-PaGe, Native PAGe or Will Your SDS Gel Accurately Indicate the Molecular Weight of Your Proteins? 345 Should You Use a Straight Gel or a gradient Gel? 345 What Issues Are Relevant for Isoelectric Focusing? 346 How Can You Resolve Proteins between Al 300 and 1000 kDa? What Issues are Critical for successful native page? 348 348 Location of band of interest 348 How Can You be sure that Your proteins have sufficient N Well into a Native page 348 Buffer Systems for Native PAGE What Can Go Wrong with the Performance of a Discontinuous Buffer Syste What Buffer System Should You Use for Peptide Electrophoresis? 350 Power issues 350 Constant Current or Constant VoltageWhen and Why Are Nucleic Acids Almost Always Separated via Constant Voltage? 352 Why Are Sequencing Gels Electrophoresed under Constant power? 352 Should You Run Two Sequencing Cells off the Same Power Supply under Constant Power Improving Resolution and Clarity of Protein Gels 353 How Can You Generate Reproducible Gels with Perfect Bands Every Time? Sample Preparation--Problems with Protein Samples 353 What Procedures and Strategies Should Be Used to Optimize Protein Sample Preparation Is the Problem Caused by Sample Preparation or by the Electrophoresis? 332 BoozWhy Should You Overlay the Gel? What Should You Use for an Overlay? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 341 Regarding Reproducible Polymerization, What Practices Will Ensure That Your Bands Run the Same Way Every Time? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 341 What Catalyst Concentration Should You Use? . . . . . . . . . . 343 What Is the Importance of Reagent Purity on Protein Electrophoresis and Staining? . . . . . . . . . . . . . . . . . . . . . . . 343 Which Gel Should You Use? SDS-PAGE, Native PAGE or Isoelectric Focusing? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 345 Will Your SDS Gel Accurately Indicate the Molecular Weight of Your Proteins? . . . . . . . . . . . . . . . . . . . . . . . . . . . 345 Should You Use a Straight % Gel or a Gradient Gel? . . . . . 345 What Issues Are Relevant for Isoelectric Focusing? . . . . . . 346 How Can You Resolve Proteins between Approximately 300 and 1000kDa? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 347 What Issues Are Critical for Successful Native PAGE? . . . . . . 348 Sample Solubility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 348 Location of Band of Interest . . . . . . . . . . . . . . . . . . . . . . . . . 348 How Can You Be Sure That Your Proteins Have Sufficient Negative Charge to Migrate Well into a Native PAGE Gel? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 348 Buffer Systems for Native PAGE . . . . . . . . . . . . . . . . . . . . . . . 349 What Can Go Wrong with the Performance of a Discontinuous Buffer System? . . . . . . . . . . . . . . . . . . . . . . . . . . 349 What Buffer System Should You Use for Peptide Electrophoresis? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 350 Power Issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 350 Constant Current or Constant Voltage—When and Why? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 351 Why Are Nucleic Acids Almost Always Separated via Constant Voltage? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 352 Why Are Sequencing Gels Electrophoresed under Constant Power? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 352 Should You Run Two Sequencing Cells off the Same Power Supply under Constant Power? . . . . . . . . . . . . . . . . . . . . . 352 Improving Resolution and Clarity of Protein Gels . . . . . . . . . 353 How Can You Generate Reproducible Gels with Perfect Bands Every Time? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 353 Sample Preparation—Problems with Protein Samples . . . . . . 353 What Procedures and Strategies Should Be Used to Optimize Protein Sample Preparation? . . . . . . . . . . . . . . . 353 Is the Problem Caused by Sample Preparation or by the Electrophoresis? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 354 332 Booz