3D-nanostructured Au electrodes for the event-specific detection of MON810 transgenic maize

In the present work, the development of a genosensor for the event-specific detection of MON810 transgenic maize is proposed. Taking advantage of nanostructuration, a cost-effective three dimensional electrode was fabricated and a ternary monolayer containing a dithiol, a monothiol and the thiolated capture probe was optimized to minimize the unspecific signals. A sandwich format assay was selected as a way of precluding inefficient hybridization associated with stable secondary target structures. A comparison between the analytical performance of the Au nanostructured electrodes and commercially available screen-printed electrodes highlighted the superior performance of the nanostructured ones. Finally, the genosensor was effectively applied to detect the transgenic sequence in real samples, showing its potential for future quantitative analysis

Nanomotor-based biocatalytic patterning of helical metal microstructures

A new nanomotor-based surface-patterning technique based on the movement of a magnetically powered enzyme-functionalized flexible nanowire swimmer offers the ability to create complex helical metal microstructures

First bioelectronic immunoplatform for quantitative secretomic analysis of total and metastasis-driven glycosylated haptoglobin

The glycosylation status of proteins is increasingly used as biomarker to improve the reliability in the diagnosis and prognosis of diseases as relevant as cancer. This feeds the need for tools that allow its simple and reliable analysis and are compatible with applicability in the clinic. With this objective in mind, this work reports the first bioelectronic immunoplatforms described to date for the determination of glycosylated haptoglobin (Hp) and the simultaneous determination of total and glycosylated Hp. The bioelectronic immunoplatform is based on the implementation of non-competitive bioassays using two different antibodies or an antibody and a lectin on the surface of commercial magnetic microcarriers. The resulting bioconjugates are labeled with the horseradish peroxidase (HRP) enzyme, and after their magnetic capture on disposable electroplatforms, the amperometric transduction using the H2O2/hydroquinone (HQ) system allows the single or multiple detection. The developed immunoplatform achieves limits of detection (LODs) of 0.07 and 0.46 ng mL-1 for total and glycosylated Hp in buffer solution, respectively. The immunoplatform allows accurate determination using simple and relatively short protocols (approx. 75 min) of total and glycosylated Hp in the secretomes of in vitro-cultured colorectal cancer (CRC) cells with different metastatic potentials, which is not feasible, due to lack of sensitivity, by means of some commercial ELISA kits and Western blot methodology.Funding Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. Spanish Ministerio de Ciencia e Innovación (PID2019-103899RB-I00 and RTI2018-095756-B-I00), AES-ISCIII Program co-founded by FEDER funds (PI17CIII/00045 and PI20CIII/00019 grants), TRANSNANOAVANSENS-CM Program from the Comunidad de Madrid (Grant S2018/NMT-4349).S

Revealing prevalent cancers by interrogating glycoproteins with sustainable immunoelectrochemical tools

Trabajo presentado en el 4th European Biosensor Symposium, celebrado en Aquisgrán (Alemania), del 27 al 30 de agosto de 2023Introduction. The worldwide incidence and death toll of colorectal and pancreatic cancers (CRC and PDAC) have increased considerably since 1990. For this reason, both early detection and regular follow-up are considered key factors in improving patient prognosis. In this sense, the determination of the total content of specific proteins and their aberrantly glycosylated fraction in oncologic processes could help to achieve the proposed goals. Results and Discussion. In this work, two simple but highly competitive electrochemical immunoplatforms for the determination of total and glycosylated post-translational modified haptoglobin (Hp) [1], and CA19-9 [2] (candidate biomarkers associated with colorectal and pancreatic cancer, respectively) are presented. As seen in Figure 1, these biotools are uplifted in the use of magnetic immunocaptors and another antibody or a lectin as detector elements lastly labeled with HRP, which enables subsequent amperometric detection. The presented bioplatforms exhibit attractive characteristics in terms of simplicity, affordability, and point-of-care application compared to the conventional available methodologies, highlighting low detection limits (0.07 and 0.46 ng mL¿1 for total and glycosylated Hp, respectively, and 1.5 U mL¿1 for CA19-9), and short assay times (< 2 h). The workability of these quantitative bioplatforms for the analysis of secretomes from cultured CRC cells with the distinct potential to metastasize (Hp) or serum samples from healthy and PDAC-diagnosed subjects (CA19-9) was assessed to definitely confirm full exploitation of all the above exposed enticing attributes. Conclusions. Our findings clearly revealed the unquestionable ability of these modern electrochemical immunoplatforms to discriminate between healthy and cancer-diagnosed subjects, as well as to assess disease progression, positioning these simple but effective methodologies as advanced electroanalytical tools with proven real biomedical applications, and the hope of aiding in the accurate diagnosis of prevalent and high mortality cancers