There is no device called "IS Nitro Capture." "NITRO" was the DS development codename; "IS" may be a confusion with "Iris" or "Intensity Shuttle." Here are real solutions:
Recommendation: For casual play, Analogue Pocket + DS Adapter + Dock. For professional capture, send your DS to Loopy / Merov / Katsukity for internal HDMI board install.