If you want to use EasyDMA with ADC, you will have to go with the nRF52832 or the new nRF52840 (currently only available in engineering samples). Both these chips have a SAADC peripheral supporting EasyDMA and a sampling rate of up to 200 kHz. Are you planning to transfer all the ADC data over ESB? ESB is not supported by nRF52840 yet.
Given that you sample only one channel, and can buffer up data to fill the transmission packets, this should not be a problem. Each sample will be stored in a 16-bit variable and with a sample rate of 8 kHz, this would give 128 Kb of data every second. As described in this blog post, nRF51 devices can achieve a throughput of 1.28 Mbps using ESB, and the nRF52 can achieve even higher rate. Note that this high throughput might not be compatible with legacy devices so you will need device that can support this in the other end of the link as well. nRF52832 devices can also achieve throughput of up to ~1365 Kbps using the 2 Mbit mode of BLE 5, as described in this blog post.
Given that you sample only one channel, and can buffer up data to fill the transmission packets, this should not be a problem. Each sample will be stored in a 16-bit variable and with a sample rate of 8 kHz, this would give 128 Kb of data every second. As described in this blog post, nRF51 devices can achieve a throughput of 1.28 Mbps using ESB, and the nRF52 can achieve even higher rate. Note that this high throughput might not be compatible with legacy devices so you will need device that can support this in the other end of the link as well. nRF52832 devices can also achieve throughput of up to ~1365 Kbps using the 2 Mbit mode of BLE 5, as described in this blog post.
