scholarly journals An Implantable Inductive Near-Field Communication System with 64 Channels for Acquisition of Gastrointestinal Bioelectrical Activity

Sensors ◽  
2019 ◽  
Vol 19 (12) ◽  
pp. 2810 ◽  
Author(s):  
Amir Javan-Khoshkholgh ◽  
Aydin Farajidavar

High-resolution (HR) mapping of the gastrointestinal (GI) bioelectrical activity is an emerging method to define the GI dysrhythmias such as gastroparesis and functional dyspepsia. Currently, there is no solution available to conduct HR mapping in long-term studies. We have developed an implantable 64-channel closed-loop near-field communication system for real-time monitoring of gastric electrical activity. The system is composed of an implantable unit (IU), a wearable unit (WU), and a stationary unit (SU) connected to a computer. Simultaneous data telemetry and power transfer between the IU and WU is carried out through a radio-frequency identification (RFID) link operating at 13.56 MHz. Data at the IU are encoded according to a self-clocking differential pulse position algorithm, and load shift keying modulated with only 6.25% duty cycle to be back scattered to the WU over the inductive path. The retrieved data at the WU are then either transmitted to the SU for real-time monitoring through an ISM-band RF transceiver or stored locally on a micro SD memory card. The measurement results demonstrated successful data communication at the rate of 125 kb/s when the distance between the IU and WU is less than 5 cm. The signals recorded in vitro at IU and received by SU were verified by a graphical user interface.

Author(s):  
Jordan Frith

The phrase the Internet of things was originally coined in a 1999 presentation about attaching radio frequency identification (RFID) tags to individual objects. These tags would make the objects machine-readable, uniquely identifiable, and, most importantly, wirelessly communicative with infrastructure. This chapter evaluates RFID as a piece of mobile communicative infrastructure, and it examines two emerging forms: near-field communication (NFC) and Bluetooth low-energy beacons. The chapter shows how NFC and Bluetooth low-energy beacons may soon move some types of RFID to smartphones, in this way evolving the use of RFID in payment and transportation and enabling new practices of post-purchasing behaviors.


Electronics ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 188
Author(s):  
Žiga Korošak ◽  
Nejc Suhadolnik ◽  
Anton Pleteršek

The aim of this work is to tackle the problem of modulation wave shaping in the field of near field communication (NFC) radio frequency identification (RFID). For this purpose, a high-efficiency transmitter circuit was developed to comply with the strict requirements of the newest EMVCo and NFC Forum specifications for pulse shapes. The proposed circuit uses an outphasing modulator that is based on a digital-to-time converter (DTC). The DTC based outphasing modulator supports amplitude shift keying (ASK) modulation, operates at four times the 13.56 MHz carrier frequency and is made fully differential in order to remove the parasitic phase modulation components. The accompanying transmitter logic includes lookup tables with programmable modulation pulse wave shapes. The modulator solution uses a 64-cell tapped current controlled fully differential delay locked loop (DLL), which produces a 360° delay at 54.24 MHz, and a glitch-free multiplexor to select the individual taps. The outphased output from the modulator is mixed to create an RF pulse width modulated (PWM) output, which drives the antenna. Additionally, this implementation is fully compatible with D-class amplifiers enabling high efficiency. A test circuit of the proposed differential multi-standard reader’s transmitter was simulated in 40 nm CMOS technology. Stricter pulse shape requirements were easily satisfied, while achieving an output linearity of 0.2 bits and maximum power consumption under 7.5 mW.


2020 ◽  
Vol 11 (2) ◽  
pp. 425-432 ◽  
Author(s):  
Shegufta Farazi ◽  
Fan Chen ◽  
Henry Foster ◽  
Raelene Boquiren ◽  
Shelli R. McAlpine ◽  
...  

A pH responsive pMAA nanogel that demonstrates high loading capacity and rapid intracellular delivery of hydrophilic peptides.


2021 ◽  
Vol 900 ◽  
pp. 115674
Author(s):  
Muthaiah Annalakshmi ◽  
Sakthivel Kumaravel ◽  
T.S.T. Balamurugan ◽  
Shen-Ming Chen ◽  
Ju-Liang He

2015 ◽  
Vol 51 (32) ◽  
pp. 6948-6951 ◽  
Author(s):  
Yanfeng Zhang ◽  
Qian Yin ◽  
Jonathan Yen ◽  
Joanne Li ◽  
Hanze Ying ◽  
...  

Anin vitroandin vivodrug-reporting system is developed for real-time monitoring of drug release via the analysis of the concurrently released near-infrared fluorescence dye.


2021 ◽  
Author(s):  
Biswajit Roy ◽  
Rakesh Mengji ◽  
Samrat Roy ◽  
Bipul Pal ◽  
Avijit Jana ◽  
...  

In recent times, organelle-targeted drug delivery systems gained tremendous attention due to the site specific delivery of active drug molecules resulting in enhanced bioefficacy. In this context, the phototriggered drug delivery system (DDS) for releasing an active molecule is superior as it provides spatial and temporal control over the release. So far, near infrared (NIR) light responsive organelle targeted DDS has not yet been developed. Hence, we introduced a two-photon NIR-light responsive lysosome targeted ʽAIE + ESIPTʼ active single component DDS based on naphthalene chromophore. The Two-photon absorption cross-section of our DDS is 142 GM at 850 nm. The DDS was converted into pure organic nanoparticles for biological applications. Our nano-DDS is capable of selective targeting, AIE-luminogenic imaging, and drug release within the lysosome. In vitro studies using cancerous cell lines showed that our single component photoresponsive nanocarrier exhibited enhanced cytotoxicity and real-time monitoring ability of the drug release.


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