Ovarian cancer, the lethal form of all gynecological cancers, is a big threat to women’s health. Late diagnosis at the advanced stages is one of the major reasons for the ovarian cancer-related deaths. Conventionally, the up-regulated proteins CA125 (cancer antigen 125) and HE4 (human epididymis protein 4 are used as biomarkers to diagnose the OVC malignancies. The lack of sensitivity/specificity and the false-positive results create complexity in the diagnostic process. With specificity over 90 %, HE4 is suitable for diagnosing ovarian cancer. Herein, we have developed an ultrasensitive all-graphene quantum dot (GQD) Förster resonance energy transfer (FRET) probe for the ratiometric detection of HE4 biomarker. A set of two GQD samples were solvothermally prepared and then analyzed by the morphological, structural, and photophysical characterization. One GQD sample exhibited a strong green emission around 515 nm, while the other GQD sample displayed a strong red emission around 615 nm. The good spectral overlap between the green GQD emission and red GQD excitation made them as a better choice of donor-acceptor FRET probe. The green and red-emitting GQDs were conjugated with HE4 antibody and used as donor and acceptor, respectively for the ratiometric sensing of HE4 ovarian cancer biomarker. The all GQD FRET probe was able to detect as low as 4.8 pM, along with a large dynamic detection range up to 300 nM. The selectivity and interference effect of the developed FRET probe was also investigated against different protein combinations.

卵巢癌是所有妇科癌症的致命形式，对妇女健康构成重大威胁。晚期晚期诊断是卵巢癌相关死亡的主要原因之一。通常，上调的蛋白质CA125（癌抗原125）和HE4（人附睾蛋白4）被用作诊断OVC恶性肿瘤的生物标记物，缺乏敏感性/特异性和假阳性结果在诊断过程中造成了复杂性。特异性超过90％，HE4适用于诊断卵巢癌，在此，我们开发了一种超灵敏的全石墨烯量子点（FQ）Förster共振能量转移（FRET）探针，用于按比例检测HE4生物标记物，一组两个GQD样品溶剂热制备，然后通过形态，结构，和光物理特征。一个GQD样品在515 nm附近表现出强烈的绿色发射，而另一个GQD样品在615 nm附近表现出强烈的红色发射。绿色GQD发射和红色GQD激发之间的良好光谱重叠使它们成为供体-受体FRET探针的更好选择。将绿色和红色发光GQD与HE4抗体偶联，分别用作供体和受体，以按比例感测HE4卵巢癌生物标志物。所有GQD FRET探针都能检测到低至4.8 pM，动态检测范围高达300 nM。还针对不同的蛋白质组合研究了开发的FRET探针的选择性和干扰作用。而其他GQD样品在615 nm附近显示出强红色发射。绿色GQD发射和红色GQD激发之间的良好光谱重叠使它们成为供体-受体FRET探针的更好选择。将绿色和红色发光GQD与HE4抗体偶联，分别用作供体和受体，以按比例感测HE4卵巢癌生物标志物。所有GQD FRET探针都能检测到低至4.8 pM，动态检测范围高达300 nM。还针对不同的蛋白质组合研究了开发的FRET探针的选择性和干扰作用。而其他GQD样品在615 nm附近显示出强红色发射。绿色GQD发射和红色GQD激发之间的良好光谱重叠使它们成为供体-受体FRET探针的更好选择。将绿色和红色发光GQD与HE4抗体偶联，分别用作供体和受体，以按比例感测HE4卵巢癌生物标志物。所有GQD FRET探针都能检测到低至4.8 pM，动态检测范围高达300 nM。还针对不同的蛋白质组合研究了开发的FRET探针的选择性和干扰作用。将绿色和红色发光GQD与HE4抗体偶联，分别用作供体和受体，以按比例感测HE4卵巢癌生物标志物。所有GQD FRET探针都能检测到低至4.8 pM，动态检测范围高达300 nM。还针对不同的蛋白质组合研究了开发的FRET探针的选择性和干扰作用。将绿色和红色发光GQD与HE4抗体偶联，分别用作供体和受体，以按比例感测HE4卵巢癌生物标志物。所有GQD FRET探针都能检测到低至4.8 pM，动态检测范围高达300 nM。还针对不同的蛋白质组合研究了开发的FRET探针的选择性和干扰作用。