Photonic Crystal Effects on Upconversion Enhancement of LiErF4:0.5%Tm3+@LiYF4 for Noncontact Cholesterol Detection

• DOI: 10.1021/acsami.1c21834
• Publication Date: 2021-12-29T15:21:04Z
• Authors: Ling Zhang; Songtao Hu; Yang Lu; Bin Jiang; Xiaomin Liu; Xiaodan Li; Xu Zhao; Xu Yan; Chenguang Wang; Xiaoteng Jia; Fengmin Liu; Biao Dong; Geyu Lu
• Keywords: vital compound; Biocompatible Materials; Biosensing Techniques; human health; Biochemistry; photonic band gap; 01 natural sciences; designed biosensor; Space Science; Materials Testing; wavelength excitation property; Yttrium; photonic crystal effects; fold enhancement; noncontact biosensor based; 5 ′- tetramethylbenzidine; Infectious Diseases; clinical diagnosis; Cholesterol; photonic crystals; Thulium; 4 </ sub; Medicine; opcs ); cholesterol cascade reactions; photonic crystal; concentration levels; alternative strategy; excellent specificity; Erbium; enhanced upconversion nanoparticles; 5; selectively tune; Chemical Sciences not elsewhere classified; detection limit; excitation field; Information Systems not elsewhere classified; ultimately achieved; highly consistent; 535; Lithium; 6 μm; upconversion enhancement; testing results; Humans; clinical cholesterol detection; Particle Size; 980 nm excitation; unique multi; oxidation products; luminescence intensity; Photons; accurate monitoring; great significance; Fluorine; 0104 chemical sciences; clinical diagnostic data; free cholesterol detection; 3 ′; various diseases; Nanoparticles; tightly associated; Neuroscience

Cholesterol is a vital compound in maintenance for human health, and its concentration levels are tightly associated with various diseases. Therefore, accurate monitoring of cholesterol is of great significance in clinical diagnosis. Herein, we fabricated a noncontact biosensor based on photonic crystal-enhanced upconversion nanoparticles (UCNPs) for highly sensitive and interference-free cholesterol detection. By compounding LiErF4:0.5%Tm3+@LiYF4 UCNPs with poly(methyl methacrylate) (PMMA) photonic crystals (OPCs), we were able to selectively tune the coupling of the photonic band gap to the excitation field and modulate the upconversion (UC) luminescence intensity, given the unique multi-wavelength excitation property of LiErF4:0.5%Tm3+@LiYF4. A 48.5-fold enhancement of the monochromatic red UC emission was ultimately achieved at 980 nm excitation, ensuring improved detection sensitivity. Based on the principle of quenching of the intense monochromic red UC emission by the oxidation products of 3,3',5,5'-tetramethylbenzidine (TMB) yielded from the cholesterol cascade reactions, the biosensor has a detection limit of 1.6 μM for cholesterol with excellent specificity and stability. In addition, the testing results of the as-designed biosensor in patients are highly consistent with clinical diagnostic data, providing a sensitive, reliable, reusable, interference-free, and alternative strategy for clinical cholesterol detection.