Nanomaterial Labels in Lateral Flow Immunoassays for Point-of-Care-Testing

Lateral flow immunoassays(LFIAs) have been developed rapidly in recent years and used in a wide range of application at point-of-care-testing(POCT),where small biomolecules can be conveniently examined on a test strip.Compared with other biochemical detection methods such as ELISA(enzyme linked immunosorbent assay) or mass spectrometry method,LFIAs have the advantages of low cost,easy operation and short time-consuming.However,it suffers from low sensitivity since conventional LFIA can only realize qualitative detection based on colorimetric signals.With the increasing demand for more accurate and sensitive determination,novel nanomaterials have been used as labels in LFIAs due to their unique advantages in physical and chemical properties.Colloidal gold,fluorescent nano particles,SERSactive nanomaterials,magnetic nanoparticles and carbon nanomaterials are utilized in LFIAs to produce different kinds of signals for quantitative or semi-quantitative detection.This review paper first gives a description of the LFIA principles,and then focuses on the state-of-the-art nanomaterial labelling technology in LFIAs.At last,the conclusion and outlook are given to inspire exploration of more advanced nanomaterials for the development of future LFIAs.

An integrated microfluidic device for the simultaneous detection of multiple antibiotics

Residual antibiotics in food pose a serious long-term threat to human health.Therefore,an on-site visualization method for antibiotic detection is required.However,the requirements of traditional antibiotic testing methods in terms of operator proficiency and equipment cost hinder the rapid point-of-caretesting detection of suspected samples.Herein,we reported an integrated microfluidic device combining a microfluidic chip containing cruciform valves with immunochromatographic strips for the rapid detection of multiple antibiotics in milk.The rapid qualitative and quantitative analysis of four types of antibiotics(sulfonamides,β-lactams,streptomycin,and tetracyclines)was performed using mobile phone photography and mobile phone application analysis.The detection time was maintained at 10 min.The limits of detection(LODs)for the four antibiotics were 0.15,0.12,0.25,and 0.29 ng/mL,respectively,and the selectivity for the different antibiotics was observed even in a highly complex matrix.This device successfully integrated separation and real-time detection onto a chip and might provide a promising perspective for the detection of multiple antibiotics in milk.

Detection of helminths by loop-mediated isothermal amplification assay:a review of updated technology and future outlook

Background:Helminths are endemic in more than half of the world's countries,raising serious public health concerns.Accurate diagnosis of helminth infection is crucial to control strategies.Traditional parasitological methods,serological tests and PCR-based assays are the major means of the diagnosis of helminth infeaion,but they are time-consuming and/or expensive,and sometimes provide inaccurate results.Loop mediated isothermal amplification(LAMP)assay,a sensitive,simple and rapid method was therefore developed for deteaion of helminths.This study aims to discuss the current status of application of LAMP on helminths detection and to make a comprehensive evaluation about this updated technology and its future outlook by comparing with several other diagnostic methods.Main body:This review summarizes LAMP assay applied for helminth detection and helminthiasis surveillance.The basic principle of LAMP is introduced to help better understand its characteristics and each reported assay is assessed mainly based on its detection sensitivity,specificity and limitations,in comparison with other common diagnostic tests.Moreover,we discuss the limitations of the assays so as to clarify some potential ways of improvement.Conclusions:Here,we summarize and discuss the advantages,disadvantages and promising future of LAMP in heliminth detection,which is expected to help update current knowledge and future perspectives of LAMP in highly sensitive and specific diagnosis and surveillance of helminthiasis and other parasitic diseases,and can contribute to the elimination of the diseases from endemic areas.