Non enzymatic glucose biosensor design, fabrication, and application.

O diabetes é uma das quatro principais doenças não transmissíveis e se tornou uma das doenças que mais crescem no mundo. Será a sétima principal causa de morte em todo o mundo até 2030. A Federação Internacional de Diabetes (IDF) divulgou um novo relatório que demonstra que a população global com diabetes atingiu 537 milhões, aumentando 16% desde sua estimativa anterior em 2019. Infelizmente, não há cura conhecida para esta condição crônica de saúde; a única alternativa para prevenir complicações para pacientes com diabetes é monitorar constantemente seus níveis de glicose no sangue. Além disso, o intervalo seguro para os níveis de glicose no sangue é muito estreito (entre 80-120 mg/dl). Portanto, o método de detecção deve ser capaz de detectar uma ligeira mudança na concentração nesta faixa. Para medir o nível de glicose, os biossensores são muito práticos. Um biossensor é um transdutor capaz de converter uma resposta biológica em um sinal mensurável. É apresentado um novo polímero de impressão molecular biossensorial com microfluido de micro-ondas sensível e de baixo custo. O dispositivo sensor é baseado em ressonadores de stub duplos para caracterizar soluções de glicose na água. A ponta de um dos stubs é revestida com MIP para aumentar a seletividade do sensor e, portanto, a sensibilidade em comparação com o polímero não revestido ou não impresso. O sensor foi fabricado em substrato FR4 para fins de baixo custo. Na presença do MIP, observou-se que o sensor carregado com uma solução de glicose variando de 50 mg/dL a 400 mg/dL experimentou uma mudança de frequência de absorção de 73 MHz quando as soluções fluem em um canal microfluídico passando pela área de detecção, enquanto o sensor Descobriu-se que o LLD do sensor era de 2,4 ng/dL. Os resultados experimentais mostraram uma alta sensibilidade de 1,3 MHz /(mg/dL) em termos de frequência de absorção.Diabetes is one of the four main noncommunicable diseases and has become one of the fastestgrowing diseases in the world. It will be the seventh leading cause of death worldwide by 2030. The International Diabetes Federation (IDF) has released a new report that demonstrates the global population with diabetes has reached 537 million, increasing 16% since their previous estimation in 2019. Unfortunately, there is no known cure for this chronic health condition; the only alternative to prevent complications for diabetes patients is constantly monitoring their blood glucose levels. Also, the safe range for blood glucose levels is very narrow (between 80-120 mg/dl). Therefore, the sensing method should be able to detect a slight change in concentration in this range. In order to measure the glucose level, biosensors are very practical. A biosensor is transducer capable of converting a biological response into a measurable signal. A novel, low-cost, sensitive microwave microfluidic glucose detecting biosensor incorporating molecularly imprinted polymer is presented. The sensing device is based on dual stub resonators to characterize water glucose solutions. The tip of one of the stubs is coated with MIP to increase the selectivity of the sensor and hence the sensitivity compared to the uncoated or non-imprinted polymer one. The sensor was fabricated on an FR4 substrate for low-cost purposes. In the presence of the MIP, the sensor load-ed with a glucose solution ranging from 50 mg/dL to 400 mg/dL was observed to experience an absorption frequency shift of 73 MHz when the solutions flow in a microfluidic channel passing sensing area, while the Lower Limit of Detection (LLD) of the sensor was discovered to be 2.4 ng/dL. The experimental results showed a high sensitivity of 1.3 MHz /(mg/dL) in terms of absorption frequency

A Highly Sensitive Molecularly Imprinted Polymer (MIP)-Coated Microwave Glucose Sensor

A novel, low-cost, sensitive microwave microfluidic glucose detecting biosensor incorporating molecularly imprinted polymer (MIP) is presented. The sensing device is based on a stub resonator to characterize water glucose solutions. The tip of one of the stubs is coated with MIP to increase the selectivity of the sensor and hence the sensitivity compared to the uncoated or to the coated with non-imprinted polymer (NIP) sensor. The sensor was fabricated on a FR4 substrate for low-cost purposes. In the presence of the MIP, the sensor loaded with a glucose solution ranging from 50 mg/dL to 400 mg/dL is observed to experience an absorption frequency shift of 73 MHz when the solutions flow in a microfluidic channel passing sensing area, while the lower limit of detection (LLD) of the sensor is discovered to be 2.4 ng/dL. The experimental results show a high sensitivity of 1.3 MHz/(mg/dL) in terms of absorption frequency

A Microwave-Based Microfluidic Cell Detecting Biosensor for Biological Quantification Using the Metallic Nanowire-Filled Membrane Technology

A label-free, sensitive, miniaturized sensing device was developed for detecting living cells in their flow stream. The outstanding performance of this biosensor in distinguishing living cells in cell suspension was achieved by integrating microstrip stub resonator above a microfluidic structure using the metallic nanowire-filled membrane technology. The cell suspension flows in a microfluidic channel placed between the tip of the stub resonator and its ground plane as the substrate to take advantage of the uniform and concentrated field distribution. We studied the changes in relative permittivity due to the presence of a single living cell in the phase of the transmitted signal (S21). An average variation of as much as 22.85 ± 1.65° at ~11.1 GHz is observed for the living cell sensing using this optimized device. This biosensor could detect rapid flowing cells in their biological medium in real-time and hence, can be used as an early diagnosis and monitoring tool for diseases