Fluorescence Detection of Carbofuran in Aqueous Extracts Based on Dual-emission SiO2 @Y2 O3 :(Eu3+ ,Tb3+ )@MIP Core-shell structurally Nanoparticles

Molecularly Imprinted Ratiometric Fluorescent Sensors for Analysis of Pharmaceuticals and Biomarkers

Currently, analyzing pharmaceuticals and biomarkers is crucial for ensuring medication safety and protecting life and health, and there is an urgent need to develop new and efficient analytical techniques in view of the limitations of traditional analytical methods. Molecularly imprinted ratiometric fluorescent (MI-RFL) sensors have received increasing attention in the field of analytical detection due to their high selectivity, sensitivity and anti-interference ability, short response time, and visualization. This review summarizes the recent advances of MI-RFL sensors in the field of pharmaceuticals and biomarkers detection. Firstly, the fluorescence sources and working mechanisms of MI-RFL sensors are briefly introduced. On this basis, new techniques and strategies for preparing molecularly imprinted polymers, such as dummy template imprinting, nanoimprinting, multi-template imprinting, and stimulus-responsive imprinting strategies, are presented. Then, dual- and triple-emission types of fluorescent sensors are introduced. Subsequently, specific applications of MI-RFL sensors in pharmaceutical analysis and biomarkers detection are highlighted. In addition, innovative applications of MI-RFL sensors in point-of-care testing are discussed in-depth. Finally, the challenges of MI-RFL sensors for analysis of pharmaceuticals and biomarkers are proposed, and the research outlook and development trends of MI-RFL sensors are prospected.

Carbofuran pesticide toxicity to the eye

Pesticide exposure to eyes is a major source of ocular morbidities in adults and children all over the world. Carbofuran (CF), N-methyl carbamate, pesticide is most widely used as an insecticide, nematicide, and acaricide in agriculture, forestry, and gardening. Contact or ingestion of carbofuran causes high morbidity and mortality in humans and pets. Pesticides are absorbed in the eye faster than other organs of the body and damage ocular tissues very quickly. Carbofuran exposure to eye causes blurred vision, pain, loss of coordination, anti-cholinesterase activities, weakness, sweating, nausea and vomiting, abdominal pain, endocrine, reproductive, and cytotoxic effects in humans depending on amount and duration of exposure. Pesticide exposure to eye injures cornea, conjunctiva, lens, retina, and optic nerve and leads to abnormal ocular movement and vision impairment. Additionally, anticholinesterase pesticides like carbofuran are known to cause salivation, lacrimation, urination, and defecation (SLUD). Carbofuran and its two major metabolites (3-hydroxycarbofuran and 3-ketocarbofuran) are reversible inhibitors of acetylcholinesterase (AChE) which regulates acetylcholine (ACh), a neurohumoral chemical that plays an important role in corneal wound healing. The corneal epithelium contains high levels of ACh whose accumulation by AChE inhibition after CF exposure overstimulates muscarinic ACh receptors (mAChRs) and nicotinic ACh receptors (nAChRs). Hyper stimulation of mAChRs in the eye causes miosis (excessive constriction of the pupil), dacryorrhea (excessive flow of tears), or chromodacryorrhea (red tears). Recent studies reported alteration of autophagy mechanism in human cornea in vitro and ex vivo post carbofuran exposure. This review describes carbofuran toxicity to the eye with special emphasis on corneal morbidities and blindness.