Construction Of Zinc Germanate Immunoluminescence Nanoprobe For The Detection Of Urinary Tract Infections

Urinary tract infections(UTIs),the inflammations caused by pathogenic bacterial invasion in urinary tracts,have been considered to be one of the most common diseaserelated infections worldwide.As a significant threat to human health,UTIs can cause pyelonephritis,urosepsis,premature birth,and even death.Thus,periodic check-ups are essential for UTI patients after recovery due to the high recurrence rates.However,urine culture,as the diagnostic gold standard for UTIs,requires time-consuming processes,leading to considerable economic burden to patients.Development of an immediate,convenient,and economical urinalysis method will be of extreme significance for the rapid diagnosis and early intervention of UTIs.In recent years,immunoluminescence has been widely used in the fields of biosensing and clinical diagnosis due to its high sensitivity and specificity.Moreover,the visual signal produced by luminescence can be observed by the naked eye,making it suitable to establish point-of-care(POC)testing.However,reliance on manual observation rather than spectrophotometric measurement leads to large subjective uncertainty,as well as difficulty in reporting quantitative data.As one type of digital technology,machine vision(MV)has emerged as ‘computer eyes’ to simulate human visual function and objective perception.The MV algorithm can report accurate and reliable results after rapid processing and analysis of digital images captured by cameras.Furthermore,the results can be easily quantified due to the robust computing algorithms,thus eliminating subjective errors in manual observations.In this regard,MV is capable of more reliable POC applications and thus is promising for developing ‘family doctor’diagnosis.In this study,we synthesized zinc germanate immunoluminescence nanoprobes(ZGO: Mn NPs),which specifically detected bacterial pathogens,and studied its detection performance.Besides,we integrated a MV-based image algorithm into photonic crystal-based substrate to construct an POC platform for luminescence quantitation of ZGO: Mn NPs.For a further step,we used this platform to achieve POC testing of bacteria pathogens in human urine and evaluated its performance in detection of UTIs.The detailed contents are described as follows:(1)Luminescence zinc germanate nanorods,prepared by hydrothermal method,was modified with carboxyl groups and further functionalized with antibodies to bacteria.This probe can bind to the surfaces of bacteria through antibody-antigen recognition,which achieving the specific detection of bacterial pathogens.We confirmed that this probe has excellent luminescence properties,high specificity and high sensitivity.Thus,it has great potential for constructing the POC detection strategy of bacterial pathogens and the family diagnosis of urinary tract infection.(2)After photonic crystal-based substrate and MV-based image processing program were developed,an immunoluminescence nanoprobe platform was constructed to quantitatively analyze luminescence of ZGO: Mn NPs,and then used for detection of bacterial pathogens in human urine samples.In addition,we evaluated the feasibility,specificity and detection limit of this platform.The results show that this cooperation between algorithm and nanoprobes results in a low detection limit and wide dynamic range.For patients with chronic diseases,such as hypertension and diabetes,this immunoluminescence nanoprobe platform is expected to provide a high-quality,reliable,and affordable tool for modern health management and personalized medicine in the big data era.