Home-made chemically competent cells generally have an order of magnitude lower competence than commercially prepared competent cells. Sometimes even less. They're good for routine plasmid maintenance, but they can be tricky to use for cloning where you may have low-efficiency ligations. I'd recommend testing a control plasmid, as suggested above. When you run the test transformation transform more DNA than usual and plate more cells than usual. I prepared chemically competent cells using the LabRat protocol (http://www.thelabrat.com/protocols/23.shtml), and followed NEB's high efficiency transformation protocol (https://www.neb.com/protocols/1/01/01/high-efficiency-transformation-protocol-c2987). I'd suggest that you transform up to 10ng of plasmid and plate up to 50-100ul of the transformed cells. That should give you some colonies, but it may give you a lawn -- so plate a few dilutions as well.
You can use a commercially available high quality plasmid to transform the competent cells and check the transformation efficiency. If you are using your own plasmid please check the antibiotic resistance gene and plate to screen transformants by using appropriate antibiotic selection.
Highly competent BL21 cells are difficult to make in-house. Nevertheless, check the efficiency by transforming the cells with known concentration of pUC19.
Home-made chemically competent cells generally have an order of magnitude lower competence than commercially prepared competent cells. Sometimes even less. They're good for routine plasmid maintenance, but they can be tricky to use for cloning where you may have low-efficiency ligations. I'd recommend testing a control plasmid, as suggested above. When you run the test transformation transform more DNA than usual and plate more cells than usual. I prepared chemically competent cells using the LabRat protocol (http://www.thelabrat.com/protocols/23.shtml), and followed NEB's high efficiency transformation protocol (https://www.neb.com/protocols/1/01/01/high-efficiency-transformation-protocol-c2987). I'd suggest that you transform up to 10ng of plasmid and plate up to 50-100ul of the transformed cells. That should give you some colonies, but it may give you a lawn -- so plate a few dilutions as well.
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