Drops: 4. Gelatinous or particulated precipitate.

4. Gelatinous or particulated precipitate.

The drop contains gelatinous protein precipitate, sometimes hard to see because it can be transparent.
Check the drop with dark-field illumination: the structural elements appear bright on a dark background.

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This is a good starting point (when no crystals are found). Optimize the condition by varying the pH, add a substrate or inhibitor or additive.

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With high PEG concentrations (viscose) the protein precipitated when mixing the drop. The drop will contain regions of heavy precipitate and regions that are clear.
Lower the precipitant concentration.