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1.
Biomed Microdevices ; 24(4): 41, 2022 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-36399220

RESUMO

Lung cancer is the leading cause of cancer death in the United States. It has the lowest 5-year survival rate among the most common cancers and therefore, early diagnosis is critical to improve the survival rate. In this paper, a new handheld electronic device is proposed to detect nine lung cancer biomarkers in the exhaled breath. An electrochemical gas sensor was produced through deposition of a thin layer of graphene and Prussian blue on a chromium-modified silicon substrate. Selective binding of the analyte was formed by molecular imprinting polymer (MIP). Subsequent polymerization and removal of the analyte yielded a layer of a conductive polymer on top of the sensor containing molecularly imprinted cavities selective for the target molecule. The sensors were tested over 1-20 parts per trillion (ppt) level of concentration while the sensor resistance has been monitored as the sensors react to the analyte by resistance change. Pentane sensor was also tested for selectivity. A printed circuit board was designed to measure the resistance of each sensor and send the data to a developed application in smartphone through Bluetooth. This handheld device has the potential to be used as a diagnostic method in the near future.


Assuntos
Biomarcadores Tumorais , Neoplasias Pulmonares , Humanos , Polímeros/química , Neoplasias Pulmonares/diagnóstico , Pulmão , Eletrônica
2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 6167-6170, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34892524

RESUMO

A novel magnetoelectric (ME) antenna is fabricated to be integrated to the on-chip energy harvesting circuit for brain-computer interface applications. The proposed ME antenna resonates at the frequency of 2.57 GHz while providing a bandwidth of 3.37 MHz. The proposed rectangular ME antenna wireless power transfer efficiency is 0.304 %, which is considerably higher than that of micro-coils.Clinical Relevance- This provides a suitable energy harvesting efficiency for wirelessly powering up the brain implant devices.


Assuntos
Interfaces Cérebro-Computador , Tecnologia sem Fio , Próteses e Implantes
3.
Analog Integr Circuits Signal Process ; 105(3): 407-415, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34511725

RESUMO

A low-noise amplifier (LNA) topology with tunable input matching and noise cancellation is introduced and described in this paper, which was designed and optimized to interface with a magnetoelectric (ME) antenna in a 0.35 µm MEMS-compatible CMOS process. Compared to conventional antennas, acoustically actuated ME antennas have significantly smaller area for ease of integration. The LNA was simulated with an ME antenna model that was constructed based on antenna measurements. Input matching at the LNA-antenna interface is controlled with a circuit that varies the effective impedance of the gate inductor using a control voltage. Tunability of 455 MHz around 2.4 GHz is achieved for the optimum S11 frequency with a control voltage range of 0.3 V to 1.2 V. The proposed LNA has a noise cancelling feedback loop that improves the noise figure by 4.1 dB. The post-layout simulation results of the LNA show a 1-dB compression point of -7.4 dBm with an S21 of 17.8 dB.

4.
Alzheimers Dement (Amst) ; 12(1): e12088, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33088894

RESUMO

INTRODUCTION: Novel sensors were developed to detect exhaled volatile organic compounds to aid in the diagnosis of mild cognitive impairment associated with early stage Alzheimer's disease (AD). The sensors were sensitive to a rat model that combined the human apolipoprotein E (APOE)4 gene with aging and the Western diet. METHODS: Gas sensors fabricated from molecularly imprinted polymer-graphene were engineered to react with alkanes and small fatty acids associated with lipid peroxidation. With a detection sensitivity in parts per trillion the sensors were tested against the breath of wild-type and APOE4 male rats. Resting state BOLD functional connectivity was used to assess hippocampal function. RESULTS: Only APOE4 rats, and not wild-type controls, tested positive to several small hydrocarbons and presented with reduced functional coupling in hippocampal circuitry. DISCUSSION: These results are proof-of-concept toward the development of sensors that can be used as breath detectors in the diagnosis, prognosis, and treatment of presymptomatic AD.

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