This study introduces a novel fluorescent probe, quinoline-derived half-curcumin-dioxaborine (Q-OB), for detecting amyloid-β (Aβ) oligomers in cerebrospinal fluid (CSF) samples from Alzheimer's disease (AD) patients. Q-OB was designed to finely tailor the hydrophobicity of its biannulate donor motifs, enhancing its sensitivity and selectivity towards Aβ oligomers. In vitro, Q-OB effectively monitored the oligomerization of Aβ during amyloid fibril formation, demonstrating its potential for early diagnosis of AD. The fluorescence intensity of Q-OB in AD patients' CSF showed significant changes, with log (I/I0) values of 0.34 ± 0.13 for cognitive normal, 0.15 ± 0.12 for mild cognitive impairment, and 0.14 ± 0.10 for AD dementia, indicating a clear distinction between AD stages. These findings suggest that Q-OB can serve as a reliable tool for early diagnosis of AD, potentially aiding in the development of appropriate treatment strategies. The study also highlights the importance of early diagnosis in AD, emphasizing the need for more accurate and accessible diagnostic methods.This study introduces a novel fluorescent probe, quinoline-derived half-curcumin-dioxaborine (Q-OB), for detecting amyloid-β (Aβ) oligomers in cerebrospinal fluid (CSF) samples from Alzheimer's disease (AD) patients. Q-OB was designed to finely tailor the hydrophobicity of its biannulate donor motifs, enhancing its sensitivity and selectivity towards Aβ oligomers. In vitro, Q-OB effectively monitored the oligomerization of Aβ during amyloid fibril formation, demonstrating its potential for early diagnosis of AD. The fluorescence intensity of Q-OB in AD patients' CSF showed significant changes, with log (I/I0) values of 0.34 ± 0.13 for cognitive normal, 0.15 ± 0.12 for mild cognitive impairment, and 0.14 ± 0.10 for AD dementia, indicating a clear distinction between AD stages. These findings suggest that Q-OB can serve as a reliable tool for early diagnosis of AD, potentially aiding in the development of appropriate treatment strategies. The study also highlights the importance of early diagnosis in AD, emphasizing the need for more accurate and accessible diagnostic methods.