Construction of eco-friendly dual carbon dots ratiometric fluorescence probe for highly selective and efficient sensing mercury ion.

In present work, blue carbon dots (b-CDs) were derived from ammonium citrate and guanidine hydrochloride, and red carbon dots (r-CDs) were stemmed from malonate, ethylenediamine and meso­tetra (4-carboxyphenyl) porphin based on facile hydrothermal method. Eco-friendly ratiometric fluorescence probe was innovatively constructed to effectively measure Hg2+ utilizing b-CDs and r-CDs. The developed probe displayed two typical emission peaks at 450 nm from b-CDs and 650 nm from r-CDs under the excitation at 360 nm. Mercury ion has strong quenching effect on the fluorescence intensity at 450 nm due to the electron transfer process and the fluorescence change at 450 nm was used as the response signal, whereas the fluorescence intensity at 650 nm kept unchangeable which resulted from the chemical inertness between Hg2+ and r-CDs, serving as the reference signal in the sensing system. Under optimal circumstances, this probe exhibited an excellent linearity between the fluorescence response values of ΔF450/F650 and Hg2+ concentrations over range of 0.01-10 µmol/L, and the limit of detection was down to 5.3 nmol/L. Furthermore, this probe was successfully employed for sensing Hg2+ in practical environmental water samples with satisfied recoveries of 98.5%-105.0%. The constructed ratiometric fluorescent probe provided a rapid, environmental-friendly, reliable, and efficient platform for measuring trace Hg2+ in environmental field.

Pharmaceutical waste management system - Are the current techniques sustainable, eco-friendly and circular? A review.

Most households and healthcare facilities usually dispose of contaminated, unused, or expired (CUE) medicines with municipal wastes, the disposal of which usually amounts to $790/ton in the USA and £450/ton in the UK. Solid (e.g., tablets, capsules, powders) and semi-solid (e.g., ointment, creams) pharmaceuticals are managed with incineration/pyrolysis, encapsulation, and engineered landfills, whereas wastewater treatment plants (WWTPs) are recommended for liquid pharmaceutical wastes (PWs). However, to date, the sustainability and eco-friendliness profile of these techniques are only subjectively ensured, leading to controversial viewpoints in many guidelines. Each technique has relative strengths and weaknesses, and their comparative weighting to maximize these profiles is sought after. The present comprehensive review aims to fulfil knowledge gaps in this regard. Four electronic databases (e.g., PubMed/MEDLINE, Scopus, and ScienceDirect) were searched for PW management (PWM)-related qualitative and quantitative articles published till December 31, 2022. Articles without details of waste disposal techniques and their health and environmental impacts were excluded. Based on the literature review, we determine that incineration can be considered a sustainable option for solid and semi-solid PWs, and WWTPs can be eco-friendly for liquid PWs, whereas encapsulation and landfilling are less sustainable. It is high time that objectively proven sustainable and eco-friendly techniques be implemented for PWM based on their dosage forms or nature of hazards. Medicine take-back, eco-pharmacovigilance, extended producer responsibility, co-payment, and life cycle analysis of pharmaceuticals focusing on reduction, reuse/re-dispensing can be integrated to make existing models sustainable, circular, and eco-friendly.

The effect of credence attributes on willingness to pay a premium for organic food: A moderated mediation model of attitudes and uncertainty.

Objective: With consumers' concerns about food safety and the environment growing, the interest in organic food has increased. However, due to the late start of the organic food market in China, the market size of the Chinese organic food industry is still relatively small. This study aims to examine whether organic food credence attributes have an impact on consumers' attitudes and willingness to pay a premium (WTPP), in order to provide valuable information to facilitate the development of the organic food market in China. Methods: A questionnaire survey was conducted with 647 respondents in China. Structural equation modeling (SEM) was utilized to verify the model and test the relationships among the constructs. Results: SEM analyses showed that credence attributes stimulate consumers' attitudes and increase consumers' WTPP. Utilitarian attitudes and hedonistic attitudes play a partially mediating role in the relationship between credence attributes and WTPP. Uncertainty negatively moderates the role between utilitarian attitudes and WTPP, while it positively moderates the role between hedonistic attitudes and WTPP. Discussion: The findings reveal the motivations and barriers for Chinese consumers to purchase organic food at a premium, providing a theoretical basis for companies to gain a deeper understanding of consumer groups and develop organic food marketing strategies.

A Modified 3D-QSAR Model Based on Ideal Point Method and Its Application in the Molecular Modification of Plasticizers with Flame Retardancy and Eco-Friendliness.

The addition of plasticizers makes plastics flammable, and thus, poses a potential risk to the environment. In previous researches, plasticizers with flame retardancy had been synthesized, but their eco-friendliness had not been tested or described. Thus, in this paper, eco-friendliness plasticizers with flame retardancy were designed based on phthalic acid esters (PAEs), which are known as common plasticizers and major plastic additives. For a comprehensive analysis, such as flammability, biotoxicity, and enrichment effects, 17 PAEs' comprehensive evaluation values were calculated based on the ideal point method. Further, a multi-effect three-dimensional quantitative structure-activity relationship (3D-QSAR) model of PAEs' flammability, biotoxicity and enrichment effects was constructed. Thus, 18 dimethyl phthalate (DMP) derivatives and 20 diallyl phthalate (DAP) derivatives were designed based on three-dimensional contour maps. Through evaluation of eco-friendliness and flammability, six eco-friendly PAE derivatives with flame retardancy were screened out. Based on contour maps analysis, it was confirmed that the introduction of large groups and hydrophobic groups was beneficial to the simultaneous improvement of PAEs' comprehensive effects, and multiple effects. In addition, the group properties were correlated significantly with improved degrees of the comprehensive effects of corresponding PAE derivatives, confirming the feasibility of the comprehensive evaluation method and modified scheme.