DNA and amino acids are important biomolecules in living organisms. Probing such biomolecules with structural characters can provide valuable information for life study. Here, gold plasmonic nanopores (GPNs) with high SERS activity (a local enhancement factor higher than 109) are synthesized at the tip of a glass nanopipette. An electric field drives individual molecules to translocate through the GPNs, which enables in situ collection of the surface-enhanced Raman scattering (SERS). Nonresonant biomolecules, including nucleobases, amino acids, and oligonucleotides (DNA), with single nucleobase differences can be distinguished. The intensity of SERS is tunable by modulating the affinity between DNA and the GPNs. The present study shows the feasibility of applying a plasmonic nanopore to DNA and protein detection, which may also provide an easy way for tracking single molecule translocation by developing a well-defined single plasmonic nanopore.

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Background and ObjectivesTo characterize the clinical and neuroimaging phenotypes of patients with autoantibodies to γ-aminobutyric acid type A receptor (GABAAR).MethodsTen patients with autoantibodies against GABAAR from Huashan Hospital Autoimmune Encephalitis cohort were identified. We used MRI assessments and clinical examinations to summarize major clinical profile and visualize and quantify lesion distribution features. The relationship between clinical features, neuroimaging phenotypes, and topology of GABAAR expression were further investigated.ResultsThe median age at onset of 10 patients (8 male patients and 2 female patients) with anti-GABAAR encephalitis was 41.5 years (range: 17–73 years). All patients had prominent seizures and multifocal spotted or confluent lesions involved in limbic, frontal, and temporal lobes on brain MRI. Bilateral but asymmetric lesions in cingulate gyri were observed in all patients. These involved lesions could change dynamically with immunotherapies and relapse. Distribution of patients' brain MRI lesions was positively correlated with gene expression level of β3 subunit–containing GABAAR (Spearman ρ = 0.864, p = 0.001), the main target of autoantibodies. According to topology of lesions, patients with anti-GABAAR encephalitis could be classified into 2 clinical-radiological types: confluent type with bilateral confluent lesions involved in almost all limbic, frontal, and temporal lobes and spotted type with multiple scattered small-to-medium patchy lesions. Patients with confluent type exhibited worse clinical presentations and outcomes when compared with those with spotted type (maximum modified Rankin scale [mRS]: 5 [5–5] vs 3.5 [3–4], respectively, p = 0.008; follow-up mRS: 4 [2–6] vs 0.5 [0–1], respectively, p = 0.016).DiscussionAnti-GABAAR encephalitis has distinctive neuroimaging phenotype. Cingulate gyri were frequently involved in this disorder. The topology of lesions might be associated with the distribution of β3 subunit–containing GABAAR and reflected patients' disease severity and outcomes.