Contactless confined readout of quartz crystal resonator sensors

PostprintA configuration and method for contactless readout of the resonance response of a thickness-shear mode quartz resonator sensor is presented. The configuration uses a crystal with a large common electrode on the front face, and one, or more, small electrodes on the back face, leading to localized sensing regions. Each back electrode is capacitively coupled to a separated tip electrode. The tip consists of a small disc and a guard ring, which confine the electric field to the electrode area and make the measurement unaffected by the stray parallel capacitances. Analysis shows that the proposed configuration can be modeled as an extension of the Butterworth-Van Dyke (BVD) circuit and that, by a proper choice of the reference frequency around resonance, it is possible to obtain frequency readings that do not depend on the tip-to-crystal stand-off distance. Experimental results show that a mass load added on the front electrode can be consistently detected and measured irrespective of the tip-to-crystal stand-off distanc

Detection of DDT and carbaryl pesticides in honey by means of immunosensors based on high fundamental frequency quartz crystal microbalance (HFF-QCM)

[EN] BACKGROUND: In recent years there has been a concern about the presence of pesticides in honey because residues of DDT and carbaryl were found in honey samples. Traditional techniques, such as chromatography, reach the required limits of detection (LOD) but are not suitable for in situ implementation in the honey-packaging industry due to their high cost and the need for highly quali¿ed staff for routine operation. Biosensors offer simplicity, low cost, and easy handling for analytical purposes in food applications. RESULTS: Piezoelectric immunosensors based on high fundamental frequency quartz crystal microbalance (HFF-QCM) have been developed for the detection of carbaryl and DDT in honey. Biorecognition was based on competitive immunoassays in the conjugate-coated format, using monoclonal antibodies as speci¿c immunoreagents. The assay LODs attained by the HFF-QCM immunosensors were 0.05 ~gL¿1 for carbaryl and 0.24 ~gL¿1 for DDT, reaching a similar level of detectability to that of the usual reference techniques. The practical LODs in honey samples were 8 ~gkg¿1 for carbaryl and 24 ~gkg¿1 for DDT. The immunosensors¿ analytical performance allow the detection of these pesticides in honey at EU regulatory levels with good accuracy (recovery percentages ranging from 94% to 130% within the working range of each pesticide standard curve) and precision (coef¿cients of variation in the 9¿36% range). CONCLUSION: The proposed immunosensor is a promising analytical tool that could be implemented for quality control in the honey packaging industry, to simplify and to reduce the cost of the routine pesticide analysis in this appreciated natural food.This research was funded by the Spanish Ministry of Economy and Competitiveness with FEDER funds (AGL Project 2013-48646-R). L.C.C. was the recipient of a PhD fellowship from the European Social Fund and the Generalitat Valenciana (ACIF / 2016/132)Cervera-Chiner, L.; March, C.; Arnau Vives, A.; Jiménez Jiménez, Y.; Montoya, Á. (2020). Detection of DDT and carbaryl pesticides in honey by means of immunosensors based on high fundamental frequency quartz crystal microbalance (HFF-QCM). Journal of the Science of Food and Agriculture. 100(6):2468-2472. https://doi.org/10.1002/jsfa.10267S246824721006Blasco, C., Fernández, M., Pena, A., Lino, C., Silveira, M. I., Font, G., & Picó, Y. (2003). Assessment of Pesticide Residues in Honey Samples from Portugal and Spain. Journal of Agricultural and Food Chemistry, 51(27), 8132-8138. doi:10.1021/jf034870mRISSATO, S., GALHIANE, M., DEALMEIDA, M., GERENUTTI, M., & APON, B. (2007). Multiresidue determination of pesticides in honey samples by gas chromatography–mass spectrometry and application in environmental contamination. Food Chemistry, 101(4), 1719-1726. doi:10.1016/j.foodchem.2005.10.034Ruiz-Toledo, J., Vandame, R., Castro-Chan, R., Penilla-Navarro, R., Gómez, J., & Sánchez, D. (2018). Organochlorine Pesticides in Honey and Pollen Samples from Managed Colonies of the Honey Bee Apis mellifera Linnaeus and the Stingless Bee Scaptotrigona mexicana Guérin from Southern, Mexico. Insects, 9(2), 54. doi:10.3390/insects9020054Juan-Borrás, M., Domenech, E., & Escriche, I. (2016). Mixture-risk-assessment of pesticide residues in retail polyfloral honey. Food Control, 67, 127-134. doi:10.1016/j.foodcont.2016.02.051Marrazza, G. (2014). Piezoelectric Biosensors for Organophosphate and Carbamate Pesticides: A Review. Biosensors, 4(3), 301-317. doi:10.3390/bios4030301March, C., García, J. V., Sánchez, Á., Arnau, A., Jiménez, Y., García, P., … Montoya, Á. (2015). High-frequency phase shift measurement greatly enhances the sensitivity of QCM immunosensors. Biosensors and Bioelectronics, 65, 1-8. doi:10.1016/j.bios.2014.10.001Cervera-Chiner, L., Juan-Borrás, M., March, C., Arnau, A., Escriche, I., Montoya, Á., & Jiménez, Y. (2018). High Fundamental Frequency Quartz Crystal Microbalance (HFF-QCM) immunosensor for pesticide detection in honey. Food Control, 92, 1-6. doi:10.1016/j.foodcont.2018.04.026Montoya, A., March, C., Montagut, Y., Moreno, M., Manclus, J., Arnau, A., … Torres, R. (2017). A High Fundamental Frequency (HFF)-based QCM Immunosensor for Tuberculosis Detection. Current Topics in Medicinal Chemistry, 17(14), 1623-1630. doi:10.2174/1568026617666161104105210Rawson, A., Venu, S., Santhi, K., Paranthaman, R., & Sureshkumar, K. (2019). Liquid chromatography–mass spectrometry/mass spectrometry method development for the determination of carbaryl residue in honey. Pharmacognosy Magazine, 15(64), 205. doi:10.4103/pm.pm_641_18Abad, A., Primo, J., & Montoya, A. (1997). Development of an Enzyme-Linked Immunosorbent Assay to Carbaryl. 1. Antibody Production from Several Haptens and Characterization in Different Immunoassay Formats. Journal of Agricultural and Food Chemistry, 45(4), 1486-1494. doi:10.1021/jf9506904Abad, A., Manclús, J. J., Mojarrad, F., Mercader, J. V., Miranda, M. A., Primo, J., … Montoya, A. (1997). Hapten Synthesis and Production of Monoclonal Antibodies to DDT and Related Compounds. Journal of Agricultural and Food Chemistry, 45(9), 3694-3702. doi:10.1021/jf9704219González-Martínez, M. A., Morais, S., Puchades, R., Maquieira, A., Abad, A., & Montoya, A. (1997). Monoclonal Antibody-Based Flow-Through Immunosensor for Analysis of Carbaryl. Analytical Chemistry, 69(14), 2812-2818. doi:10.1021/ac961068tMarch, C., Manclús, J. J., Jiménez, Y., Arnau, A., & Montoya, A. (2009). A piezoelectric immunosensor for the determination of pesticide residues and metabolites in fruit juices. Talanta, 78(3), 827-833. doi:10.1016/j.talanta.2008.12.058Mauriz, E., Calle, A., Manclús, J. J., Montoya, A., Hildebrandt, A., Barceló, D., & Lechuga, L. M. (2007). Optical immunosensor for fast and sensitive detection of DDT and related compounds in river water samples. Biosensors and Bioelectronics, 22(7), 1410-1418. doi:10.1016/j.bios.2006.06.016Sapozhnikova, Y., Simons, T., & Lehotay, S. J. (2015). Evaluation of a Fast and Simple Sample Preparation Method for Polybrominated Diphenyl Ether (PBDE) Flame Retardants and Dichlorodiphenyltrichloroethane (DDT) Pesticides in Fish for Analysis by ELISA Compared with GC-MS/MS. Journal of Agricultural and Food Chemistry, 63(18), 4429-4434. doi:10.1021/jf505651gSun, J., Dong, T., Zhang, Y., & Wang, S. (2010). Development of enzyme linked immunoassay for the simultaneous detection of carbaryl and metolcarb in different agricultural products. Analytica Chimica Acta, 666(1-2), 76-82. doi:10.1016/j.aca.2010.03.051Mauriz, E., Calle, A., Abad, A., Montoya, A., Hildebrandt, A., Barceló, D., & Lechuga, L. M. (2006). Determination of carbaryl in natural water samples by a surface plasmon resonance flow-through immunosensor. Biosensors and Bioelectronics, 21(11), 2129-2136. doi:10.1016/j.bios.2005.10.01

A Real-Time Method for Improving Stability of Monolithic Quartz Crystal Microbalance Operating under Harsh Environmental Conditions

[EN] Monolithic quartz crystal microbalance (MQCM) has recently emerged as a very promising technology suitable for biosensing applications. These devices consist of an array of miniaturized QCM sensors integrated within the same quartz substrate capable of detecting multiple target analytes simultaneously. Their relevant benefits include high throughput, low cost per sensor unit, low sample/reagent consumption and fast sensing response. Despite the great potential of MQCM, unwanted environmental factors (e.g., temperature, humidity, vibrations, or pressure) and perturbations intrinsic to the sensor setup (e.g., mechanical stress exerted by the measurement cell or electronic noise of the characterization system) can affect sensor stability, masking the signal of interest and degrading the limit of detection (LoD). Here, we present a method based on the discrete wavelet transform (DWT) to improve the stability of the resonance frequency and dissipation signals in real time. The method takes advantage of the similarity among the noise patterns of the resonators integrated in an MQCM device to mitigate disturbing factors that impact on sensor response. Performance of the method is validated by studying the adsorption of proteins (neutravidin and biotinylated albumin) under external controlled factors (temperature and pressure/flow rate) that simulate unwanted disturbances.This work was supported by the European Commission Horizon 2020 Programme, Capturing non-Amplified Tumor Circulating DA with Ultrasound Hydrodynamics, under Grant H2020FETOPEN-2016-2017/737212-CATCH-U-DNA. M. Calero is the recipient of the doctoral fellowship BES-2017-080246 from the Ministerio de Economia, Industria y Competitividad de Espana.Fernández Díaz, R.; Calero-Alcarria, MDS.; Jiménez Jiménez, Y.; Arnau Vives, A. (2021). A Real-Time Method for Improving Stability of Monolithic Quartz Crystal Microbalance Operating under Harsh Environmental Conditions. Sensors. 21(12):1-12. https://doi.org/10.3390/s21124166S112211

Fomentando el aprendizaje autorregulado en la asignatura Conversión y Procesado de la Energía mediante la incorporación de los ODS a sus contenidos

[EN] According to empirical evidence, those students who present a Self-Regulated Learning (SRL) pattern are more likely to achieve academic success. This pattern is characterized by the fact that students control their own learning processes and develop responsibility and autonomy over them. In this paper, a teaching innovation is presented that aims to promote self-regulation in students of the Energy Conversion and Processing subject of the Degree in Telecommunications Technologies and Services Engineering at the Universitat Politècnica de València. To achieve this, we propose to take advantage of the existing synergy between the Sustainable Development Goals of the United Nations Organization and the contents of the subject. Specifically, we propose a methodology that seeks to increase the level of intrinsic motivation of our students through activities that highlight the relevance and usefulness of the skills of the subject and guide the student to get involved in the learning process, fostering curiosity, understanding of work done and sense of self-efficacy. This article presents the methodology developed, the results obtained and the initial conclusions.[ES] Según las evidencias empíricas, aquellos alumnos que presentan un patrón de aprendizaje autorregulado tienen mayores posibilidades de lograr el éxito académico. Dicho patrón se caracteriza por que los estudiantes controlan sus propios procesos de aprendizaje y desarrollan responsabilidad y autonomía sobre ellos. En este trabajo, se presenta una innovación docente que tiene como objetivo potenciar la autorregulación en los estudiantes de la asignatura Conversión y Procesado de la Energía del Grado en Ingeniería de Tecnologías y Servicios de Telecomunicación de la Universitat Politècnica de València. Para lograrlo, proponemos aprovechar la sinergia existente entre los Objetivos de Desarrollo Sostenible de la Organización de las Naciones Unidas y los contenidos de la asignatura. Concretamente, planteamos una metodología que busca incrementar el nivel de motivación intrínseca de nuestros alumnos por medio de actividades que resaltan la relevancia y utilidad de las competencias de la asignatura y orientan al alumno a involucrarse en el proceso de aprendizaje, fomentando la curiosidad, la comprensión del trabajo realizado y el sentido de autoeficacia. Este artículo presenta la metodología desarrollada, los resultados obtenidos y las conclusiones iniciales.Fernández Díaz, R.; Jimenez Jimenez, Y.; Hernández Ferrer, A.; Arnau Vives, A. (2022). Fomentando el aprendizaje autorregulado en la asignatura Conversión y Procesado de la Energía mediante la incorporación de los ODS a sus contenidos. Editorial Universitat Politècnica de València. 435-444. https://doi.org/10.4995/INRED2022.2022.1579943544

A fast method for monitoring the shifts in resonance frequency and dissipation of the QCM sensors of a Monolithic array in biosensing applications

© 2021 IEEE. Personal use of this material is permitted. Permissíon from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertisíng or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.[EN] Improvement of data acquisition rate remains as an important challenge in applications with Quartz Crystal Microbalance (QCM) technology where high throughput is required. To address this challenge, we developed a fast method capable of measuring the response of a large number of sensors and/or overtones, with a high time resolution. Our method, which can be implemented in a low-cost readout electronic circuit, is based on the estimation of fr (frequency shift) and D (dissipation shift) from measurements of the sensor response obtained at a single driving frequency. By replacing slow fitting procedures with a direct calculation, the time resolution is only limited by the physical characteristics of the sensor (resonance frequency and quality factor), but not by the method itself. Capabilities of the method are demonstrated by monitoring multiple overtones with a single 5 MHz sensor and a Monolithic QCM array comprising 24 50MHz-sensors. Accuracy of the method is validated and compared with the state-of-the-art, as well as with a reference method based on impedance analysis.This work was supported in part by the Ministerio de Economía, Industria y Competitividad de España-Agencia Estatal de Investigación with Fondo Europeo de Desarrollo Regional (FEDER) Funds under Grant AGL2016-77702-R and in part by the European Commission Horizon 2020 Programme (Capturing non-amplified tumor circulating DNA with ultrasound hydrodynamics) under Agreement H2020-FETOPEN-2016-2017/737212-CATCH-UDNA. The work of María Calero was supported by the Spanish Ministry of Economy, Industry and Competitiveness, Madrid, Spain, under Grant BES-2017-080246.Fernández Díaz, R.; Calero-Alcarria, MDS.; García Narbón, JV.; Reiviakine, I.; Arnau Vives, A.; Jiménez Jiménez, Y. (2021). A fast method for monitoring the shifts in resonance frequency and dissipation of the QCM sensors of a Monolithic array in biosensing applications. IEEE Sensors Journal. 21(5):6643-6651. https://doi.org/10.1109/JSEN.2020.3042653S6643665121

High Fundamental Frequency Quartz Crystal Microbalance (HFF-QCM) immunosensor for pesticide detection in honey

[EN] Quantification of chemical residues in honey is a market requirement to ensure consumer safety. The most common method used to analyze these compounds is the LC/MS/MS methodology, which requires highly qualified technicians and a tedious pre-treatment of the sample. The honey-packaging industry needs cheaper and faster alternatives for routine control. HFF-QCM (High Fundamental Frequency Quartz Crystal Microbalance) sensors are becoming a good option due to their high sensitivity, fast detection and low cost, while avoiding complex sample pre-treatment. The HFF-QCM technology is based on piezoelectric sensors with frequencies in the range from several tenths of MHz to hundreds of MHz. In this work a 100 MHz HFF-QCM sensor was used in a monoclonal antibody-based competitive immunoassay for specific bio-recognition of carbaryl pesticide as testing contaminant. The work intends to validate the use of HFF-QCM technology, in comparison with liquid chromatography-tandem mass spectrometry (LC-MS/MS) technique, for the detection of contaminants in honey. For this purpose, the validation criteria required by SANCO 12571/2013 guidance document were considered. The precision and accuracy (recovery) of both methods were determined by comparison of 5 replicates at 4 different concentrations (from 0 to 100 ¿g/kg) using the same honey matrix. HFF-QCM technology showed good accuracy, with recovery percentages always between 110 and 120%. As regards to precision, HFF-QCM coefficients of variation (CV) were around 10% higher than those recommended by GC SANCO 12571/2013. HFF-QCM limits of detection (LOD) and quantification (LOQ) were in the same order of magnitude as those for LC-MS/MS, which allows the analysis of carbaryl residues in honey under the established maximum residue limits (MRL), without sample pre-treatment. These results show that biosensors based on HFF-QCM technology has become a serious alternative to the traditional analytical techniques for food quality and safety applications.The authors are grateful for financial support from the Ministry of Economy and Competitiveness of Spain under the project AGL2013-48646-R. We also want to thank “Generalitat Valenciana” for the financial support to hire research personnel through the grant “Ayudas para la contratación de personal investigador en formación de carácter predoctoral” to carry out this research (DOC Num.7615/15.09.2015).Cervera-Chiner, L.; Juan Borrás, MDS.; March, C.; Arnau Vives, A.; Escriche Roberto, MI.; Montoya, Á.; Jiménez Jiménez, Y. (2018). High Fundamental Frequency Quartz Crystal Microbalance (HFF-QCM) immunosensor for pesticide detection in honey. Food Control. 92:1-6. https://doi.org/10.1016/j.foodcont.2018.04.026S169

High Fundamental Frequency Quartz Crystal Microbalance (HFF-QCMD) Immunosensor for detection of sulfathiazole in honey

[EN] In this study, a piezoelectric immunosensor based on High Fundamental Frequency Quartz Crystal Microbalance (HFF-QCMD) technology was developed for detection of sulfathiazole in honey. The biorecognition was based on a competitive immunoassay in the conjugate-coated format, using monoclonal antibodies as specific im-munoreagents. The quantification of sulfathiazole was performed by building the corresponding calibration standard curve in diluted honey (1/140). Due to the competitive nature of the immunoassay, the standard curve showed a sigmoidal pattern with limits of detection (LOD) and quantification (LOQ) of 0.10 ¿g/kg and 2 ¿g/kg honey, respectively. The LOD reached by this immunosensor is 40¿50 times lower than those reported by other techniques for antibiotic detection. Moreover, this method requires minimum honey pre-treatment, making it faster and simpler than other methods. This immunosensor meets the precision and accuracy requirements established by SANCO guidelines, when sulfathiazole concentration in honey is not lower than 10 ¿g/kg. These findings could be the basis for reaching enough reliability for lower concentrations. Therefore, HFF-QCMD immunosensors can be considered a feasible alternative to current techniques for rapid and highly sensitive determination of sulfathiazole in honey with minimum sample preparation.The Spanish Ministry of Economy and Competitiveness, with FEDER-funds, has financially supported this work through the AGL 2013-48646-R project. Furthermore, authors are grateful for financial support from the European Social Fund and the Generalitat Valenciana for the PhD grant (Ayudas para la contratación de personal investigador en formación de carácter predoctoral) to Lourdes Cervera Chiner (ACIF/2016/132). The authors would also like to thank the Universitat Politècnica de València for the support provided for contracting Marisol Juan Borrás in the frame of PAID-10-17 (Ayuda para la contratación de acceso al Sistema Español de Ciencia, Tecnología e Innovación en Estructuras de Investigación).Cervera-Chiner, L.; Jiménez Jiménez, Y.; Montoya, Á.; Juan-Borras, MDS.; Pascual, N.; Arnau Vives, A.; Escriche Roberto, MI. (2020). High Fundamental Frequency Quartz Crystal Microbalance (HFF-QCMD) Immunosensor for detection of sulfathiazole in honey. Food Control. 115:1-6. https://doi.org/10.1016/j.foodcont.2020.107296S1611

High Fundamental Frequency (HFF) Monolithic Resonator Arrays for Biosensing Applications: Design, Simulations, Experimental, Characterization

© 2020 IEEE. Personal use of this material is permitted. Permissíon from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertisíng or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.[EN] Miniaturized, high-throughput, cost-effective sensing devices are needed to advance lab-on-a-chip technologies for healthcare, security, environmental monitoring, food safety, and research applications. Quartz crystal microbalance with dissipation (QCMD) is a promising technology for the design of such sensing devices, but its applications have been limited, until now, by low throughput and significant costs. In this work, we present the design and characterization of 24-element monolithic QCMD arrays for high-throughput and low-volume sensing applications in liquid. Physical properties such as geometry and roughness, and electrical properties such as resonance frequency, quality factor, spurious mode suppression, and interactions between array elements (crosstalk), are investigated in detail. In particular, we show that the scattering parameter, S 21 , commonly measured experimentally to investigate crosstalk, contains contributions from the parasitic grounding effects associated with the acquisition circuitry. Finite element method simulations do not take grounding effects into account explicitly. However, these effects can be effectively modelled with appropriate equivalent circuit models, providing clear physical interpretation of the different contributions. We show that our array design avoids unwanted interactions between elements and discuss in detail aspects of measuring these interactions that are often-overlooked.The authors would also like to thank Jorge Martínez from the Laboratory of High Frequency Circuits (LCAF) of the Universitat Politècnica de València (UPV) for assistance with profilometry, and Manuel Planes, José Luis Moya, Mercedes Tabernero, Alicia Nuez, and Joaquin Fayos from the Electron Microscopy Services of the UPV for helping with the AFM, and SEM measurements. M. Calero is the recipient of the doctoral fellowship BES-2017-080246 from the Spanish Ministry of Economy, Industry and Competitiveness, Madrid, Spain.Fernández Díaz, R.; Calero-Alcarria, MDS.; Reviakine, I.; García, JV.; Rocha-Gaso, MI.; Arnau Vives, A.; Jiménez Jiménez, Y. (2021). High Fundamental Frequency (HFF) Monolithic Resonator Arrays for Biosensing Applications: Design, Simulations, Experimental, Characterization. IEEE Sensors Journal. 21(1):284-295. https://doi.org/10.1109/JSEN.2020.3015011S28429521

High-Bandpass Filters in Electrocardiography: Source of Error in the Interpretation of the ST Segment

Introduction. Artifactual variations in the ST segment may lead to confusion with acute coronary syndromes. Objective. To evaluate how the technical characteristics of the recording mode may distort the ST segment. Material and Method. We made a series of electrocardiograms using different filter configurations in 45 asymptomatic patients. A spectral analysis of the electrocardiograms was made by discrete Fourier transforms, and an accurate recomposition of the ECG signal was obtained from the addition of successive harmonics. Digital high-pass filters of 0.05 and 0.5 Hz were used, and the resulting shapes were compared with the originals. Results. In 42 patients (93%) clinically significant alterations in ST segment level were detected. These changes were only seen in “real time mode” with high-pass filter of 0.5 Hz. Conclusions. Interpretation of the ST segment in “real time mode” should only be carried out using high-pass filters of 0.05 Hz.Buendıa Fuentes, F.; Arnau Vives, M.; Arnau Vives, A.; Jiménez Jiménez, Y.; Rueda-Soriano, J.; Zorio-Grima, E..; Osa-Saez, A.... (2012). High-Bandpass Filters in Electrocardiography: Source of Error in the Interpretation of the ST Segment. ISRN Cardiology. 2012:706217-706227. doi:10.5402/2012/706217S706217706227201

Acoustic Array Biochip Combined with Allele-Specific PCR for Multiple Cancer Mutation Analysis in Tissue and Liquid Biopsy

[EN] Regular screening of point mutations is of importance to cancer management and treatment selection. Although techniques like next-generation sequencing and digital polymerase chain reaction (PCR) are available, these are lacking in speed, simplicity, and cost-effectiveness. The development of alternative methods that can detect the extremely low concentrations of the target mutation in a fast and cost-effective way presents an analytical and technological challenge. Here, an approach is presented where for the first time an allele-specific PCR (AS-PCR) is combined with a newly developed high fundamental frequency quartz crystal microbalance array as biosensor for the amplification and detection, respectively, of cancer point mutations. Increased sensitivity, compared to fluorescence detection of the AS-PCR amplicons, is achieved through energy dissipation measurement of acoustically ¿lossy¿ liposomes binding to surface-anchored dsDNA targets. The method, applied to the screening of BRAF V600E and KRAS G12D mutations in spiked-in samples, was shown to be able to detect 1 mutant copy of genomic DNA in an excess of 104 wild-type molecules, that is, with a mutant allele frequency (MAF) of 0.01%. Moreover, validation of tissue and plasma samples obtained from melanoma, colorectal, and lung cancer patients showed excellent agreement with Sanger sequencing and ddPCR; remarkably, the efficiency of this AS-PCR/acoustic methodology to detect mutations in real samples was demonstrated to be below 1% MAF. The combined high sensitivity and technology-readiness level of the methodology, together with the ability for multiple sample analysis (24 array biochip), cost-effectiveness, and compatibility with routine workflow, make this approach a promising tool for implementation in clinical oncology labs for tissue and liquid biopsy.This work was supported by the European Union's Horizon H2020-FETOPEN-1-2016-2017 under grant agreement no. 737212 (CATCH-U-DNA).Naoumi, N.; Michaelidou, K.; Papadakis, G.; Simaiaki, AE.; Fernández Díaz, R.; Calero-Alcarria, MDS.; Arnau Vives, A.... (2022). Acoustic Array Biochip Combined with Allele-Specific PCR for Multiple Cancer Mutation Analysis in Tissue and Liquid Biopsy. ACS Sensors. 7(2):495-503. https://doi.org/10.1021/acssensors.1c02245S4955037