Sulfated lignocellulose nanofibril based composite aerogel towards adsorption-photocatalytic removal of tetracycline.

The design-on-demand of lignocellulose nanofibril-based materials for contaminant disposal is worth exploring. Herein, we mildly extract sulfated lignocellulose nanofibrils from bagasse via a deep eutectic solvent-based approach, and use them as a matrix for TiO2 nanoparticles (TNPs) towards adsorption-photocatalytic synergistic removal of tetracycline (TC). The resultant lignocellulose-based nanocomposite aerogel possessing a high specific surface area (95.3 m2/g), surface charge density (1.78 mmol/g) and well-preserved lignocellulosic structure, strongly adsorbed TC with a maximum adsorption capacity of 70 mg/g via a combination of intermolecular interactions (i.e., hydrogen bonding and π-π stacking) and electrostatic forces. Furthermore, the excellent photocatalytic activity of uniformly distributed TNPs in combination with the outstanding adsorption capacity of nanocomposite aerogel can synergistically remove TC in a dynamic and continuous process, during which ~90 % TC (10 mg/L) was efficiently removed within 40 min. HPLC-MS was performed to reveal the degradation pathways of TC. Meanwhile, our developed nanocomposite aerogel demonstrated favorable structural stability and recyclability, which together supported its durability for environmental remediation.

Multiplexed all-solid-state ion-sensitive light-addressable potentiometric sensor (ISLAPS) system based on silicone-rubber for physiological ions detection.

Light-addressable potentiometric sensor (LAPS) has been widely used in biomedical applications since its advent. As a member of the potentiometric sensors, ion-sensitive LAPS (ISLAPS) can be obtained by modifying ion selective sensing membrane on the sensor surface. Compared with the conventional ion-selective electrodes (ISEs) with liquid contact, the all-solid-state ISEs have more advantages such as easy maintenance, more convenient for miniaturization and practical applications. However, the commonly used ion-sensitive membrane (ISM) matrix like PVC has many limitations such as poor adhesion to silicone-based sensor and easy overflow of the plasticizer from the membrane. In this work, LAPS was combined with a variety of ionophore-doped all-solid-state silicone-rubber ISMs for the first time, to establish a program-controlled multiplexed ISLAPS system for physiological ions (Na+, K+, Ca2+ and H+) detection. The silicone-rubber ISMs have better adhesion to silicon-based sensors without containing plasticizers, which can avoid the plasticizer pollution and improve the long-term stability. A layer of poly(3-octylthiophene-2,5-diyl) (P3OT) was pre-modified on the sensor surface to inhibit the formation of an aqueous layer and improve the sensor lifetime. With the aid of a translation stage, the light spot automatically illuminated the detection sites in sequence, and the response of the four ions could be obtained in one measurement within 1 min. The proposed multiplexed ISLAPS has good sensitivity with micromolar limit of detection (LOD), good selectivity and long-term stability (more than 3 months). The results of the real Dulbecco's Modified Eagle Medium (DMEM) sample detection proved that the ISLAPS system can be used for the physiological ions detection, and is promising to realize a multi-parameter microphysiometer.