Two-Step Microfluidics Approach Enables Electronic Detection of Biomarkers in Blood

The potential of first-void (FV) urine as a non-invasive liquid biopsy for detection of human papillomavirus (HPV) DNA and other biomarkers has been increasingly recognized over the past decade. In this study, we investigated whether the volume of this initial urine stream has an impact on the analytical performance of biomarkers. In parallel, we evaluated different DNA extraction protocols and introduced an internal control in the urine preservative. Twenty-five women, diagnosed with high-risk HPV, provided three home-collected FV urine samples using three FV urine collection devices (Colli-Pee) with collector tubes that differ in volume (4, 10, 20 mL). Each collector tube was prefilled with Urine Conservation Medium spiked with phocine herpesvirus 1 (PhHV-1) DNA as internal control. Five different DNA extraction protocols were compared, followed by PCR for GAPDH and PhHV-1 (qPCR), HPV DNA, and HBB (HPV-Risk Assay), and ACTB (methylation-specific qPCR). Results showed limited effects of collection volume on human and HPV DNA endpoints. In contrast, significant variations in yield for human endpoints were observed for different DNA extraction methods (p < 0.05). Additionally, the potential of PhHV-1 as internal control to monitor FV urine collection, storage, and processing was demonstrated.

Download Full-text

Interfacing aptamers, nanoparticles and graphene in a hierarchical structure for highly selective detection of biomolecules in OECT devices

Scientific Reports ◽

10.1038/s41598-021-88546-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Carlotta Peruzzi ◽

Silvia Battistoni ◽

Daniela Montesarchio ◽

Matteo Cocuzza ◽

Simone Luigi Marasso ◽

...

Keyword(s):

Biomedical Applications ◽

Au Nanoparticles ◽

Limit Of Detection ◽

High Sensitivity ◽

Minimal Invasiveness ◽

Hierarchic Structure ◽

Final Response ◽

Detection Of Biomolecules ◽

Good Signal ◽

Detection Of Biomarkers

AbstractIn several biomedical applications, the detection of biomarkers demands high sensitivity, selectivity and easy-to-use devices. Organic electrochemical transistors (OECTs) represent a promising class of devices combining a minimal invasiveness and good signal transduction. However, OECTs lack of intrinsic selectivity that should be implemented by specific approaches to make them well suitable for biomedical applications. Here, we report on a biosensor in which selectivity and a high sensitivity are achieved by interfacing, in an OECT architecture, a novel gate electrode based on aptamers, Au nanoparticles and graphene hierarchically organized to optimize the final response. The fabricated biosensor performs state of the art limit of detection monitoring biomolecules, such as thrombin-with a limit of detection in the picomolar range (≤ 5 pM) and a very good selectivity even in presence of supraphysiological concentrations of Bovine Serum Albumin (BSA-1mM). These accomplishments are the final result of the gate hierarchic structure that reduces sterich indrance that could contrast the recognition events and minimizes false positive, because of the low affinity of graphene towards the physiological environment. Since our approach can be easily applied to a large variety of different biomarkers, we envisage a relevant potential for a large series of different biomedical applications.

Download Full-text

Aptamer-linked in vitro expression assay for ultrasensitive detection of biomarkers

Analytica Chimica Acta ◽

10.1016/j.aca.2020.12.036 ◽

2021 ◽

Vol 1146 ◽

pp. 118-123

Author(s):

Min-Seok Baek ◽

Kyung-Ho Lee ◽

Ju-Young Byun ◽

Yong-Beom Shin ◽

Dong-Myung Kim

Keyword(s):

Ultrasensitive Detection ◽

In Vitro Expression ◽

Detection Of Biomarkers

Download Full-text

Metal Nanoparticle and Quantum Dot Tags for Signal Amplification in Electrochemical Immunosensors for Biomarker Detection

Chemosensors ◽

10.3390/chemosensors9040085 ◽

2021 ◽

Vol 9 (4) ◽

pp. 85

Author(s):

Anton Popov ◽

Benediktas Brasiunas ◽

Asta Kausaite-Minkstimiene ◽

Almira Ramanaviciene

Keyword(s):

Signal Amplification ◽

Electrochemical Immunosensor ◽

Metal Nanoparticle ◽

Biomarker Detection ◽

Analytical Instruments ◽

Electrochemical Immunosensors ◽

Highly Sensitive ◽

Recent Developments ◽

Electrochemical Signal ◽

Detection Of Biomarkers

With the increasing importance of healthcare and clinical diagnosis, as well as the growing demand for highly sensitive analytical instruments, immunosensors have received considerable attention. In this review, electrochemical immunosensor signal amplification strategies using metal nanoparticles (MNPs) and quantum dots (Qdots) as tags are overviewed, focusing on recent developments in the ultrasensitive detection of biomarkers. MNPs and Qdots can be used separately or in combination with other nanostructures, while performing the function of nanocarriers, electroactive labels, or catalysts. Thus, different functions of MNPs and Qdots as well as recent advances in electrochemical signal amplification are discussed. Additionally, the methods most often used for antibody immobilization on nanoparticles, immunoassay formats, and electrochemical methods for indirect biomarker detection are overviewed.

Download Full-text

Raman-Spektren von SnJ4, GeJ4, TiBr4 und TiJ4 in flüssiger und kristalliner Phase / Raman Spectra of SnJ4, GeJ4, TiBr4, and TiJ4 in the Liquid and Crystalline Phase

Zeitschrift für Naturforschung B ◽

10.1515/znb-1970-1212 ◽

1970 ◽

Vol 25 (12) ◽

pp. 1374-1381 ◽

Cited By ~ 8

Author(s):

W. Kiefer ◽

H. W. Schrötter

Keyword(s):

Raman Spectra ◽

Ruby Laser ◽

Detection System ◽

Point Group ◽

Visible Region ◽

Group Symmetry ◽

Pure Liquid ◽

Electronic Detection ◽

Polarization Studies ◽

First Time

The Raman spectra of four molecules absorbing in the visible region (SnJ4, GeJ4, TiBr4, and TiJ4) are presented. They were excited with a quasi-continuous ruby laser and recorded with a special electronic detection system. Except for TiJ4, complete Raman spectra of crystal powder pellets could be obtained for the first time. The assignment reported by previous authors was confirmed by accurate polarization studies of solutions or pure liquid. The assignment is also in the solid state possible on the basis of Td point group symmetry. The fundamental vibrations of TiJ4 in solutions are: ν1 (A1) =162, ν2 (E) =51, ν3 (F2) =319 and ν4 (F2) Y = 67 cm-1

Download Full-text