We present a portable non-invasive approach for measuring indicators of inflammation and oxidative stress in the respiratory tract by quantifying a biomarker in exhaled breath condensate(EBC).We discuss the fabricatio...We present a portable non-invasive approach for measuring indicators of inflammation and oxidative stress in the respiratory tract by quantifying a biomarker in exhaled breath condensate(EBC).We discuss the fabrication and characterization of a miniaturized electrochemical sensor for detecting nitrite content in EBC using reduced graphene oxide.The nitrite content in EBC has been demonstrated to be a promising biomarker of inflammation in the respiratory tract,particularly in asthma.We utilized the unique properties of reduced graphene oxide(rGO);specifically,the material is resilient to corrosion while exhibiting rapid electron transfer with electrolytes,thus allowing for highly sensitive electrochemical detection with minimal fouling.Our rGO sensor was housed in an electrochemical cell fabricated from polydimethyl siloxane(PDMS),which was necessary to analyze small EBC sample volumes.The sensor is capable of detecting nitrite at a low over-potential of 0.7 V with respect to an Ag/AgCl reference electrode.We characterized the performance of the sensors using standard nitrite/buffer solutions,nitrite spiked into EBC,and clinical EBC samples.The sensor demonstrated a sensitivity of 0.21μAμM^(−1) cm^(−2) in the range of 20–100μM and of 0.1μAμM^(−1) cm^(−2) in the range of 100–1000μM nitrite concentration and exhibited a low detection limit of 830 nM in the EBC matrix.To benchmark our platform,we tested our sensors using seven pre-characterized clinical EBC samples with concentrations ranging between 0.14 and 6.5μM.This enzyme-free and label-free method of detecting biomarkers in EBC can pave the way for the development of portable breath analyzers for diagnosing and managing changes in respiratory inflammation and disease.展开更多
2009186 The clinical significance of noninvasive inflammatory markers in exhaled breath condensate and induced sputum in persistent asthmatic patients. TAN Chengwu(谭成戊),et al.Dept Respir Med,West China Hosp,Sichuan...2009186 The clinical significance of noninvasive inflammatory markers in exhaled breath condensate and induced sputum in persistent asthmatic patients. TAN Chengwu(谭成戊),et al.Dept Respir Med,West China Hosp,Sichuan Univ,Chengdu,Sichuan 610041.Chin J Interm Med,2009;48(4):299-303.展开更多
Background Pulmonary hypertension （PH） is a common complication of chronic obstructive pulmonary disease （COPD）. Although alveolar hypoxia is considered as a main cause of PH in COPD, structural and functional cha...Background Pulmonary hypertension （PH） is a common complication of chronic obstructive pulmonary disease （COPD）. Although alveolar hypoxia is considered as a main cause of PH in COPD, structural and functional changes of pulmonary circulation are apparent at the initial stage of COPD. We hypothesized that an inflammatory response and oxidative stress might contribute to the formation of PH in COPD. Methods We measured the levels of interleukin-6 （IL-6） and 8-iso-prostaglandin （8-iso-PSG） in exhaled breath condensate （EBC） and serum in 40 patients with COPD only or in 45 patients with COPD combined with PH. Pulmonary arterial systolic pressure （PASP） was assessed by Doppler echocardiography and defined as PH when the value of systolic pressure was greater than 40 mmHg. Results Compared with the COPD only group, the level of IL-6 in EBC was significantly increased in all 45 patients with COPD combined with PH （（8.27±2.14） ng/L vs. （4.95±1.19） ng/L, P 〈0.01）. The level of IL-6 in serum was also elevated in patients with COPD combined with PH compared with the COPD only group （（72.8±21.6） ng/L vs. （43.58±13.38） ng/L, P 〈0.01 ）. Similarly, we also observed a significant increase in the level of 8-iso-PSG in both EBC and serum in the COPD with PH group, compared with the COPD only group （EBC： （9.00±2.49） ng/L vs. （5.96±2.31） ng/L, P 〈0.01 and serum： （41.87±9.75） ng/L vs. （27.79±11.09） ng/L, P 〈0.01）. Additionally, the value of PASP in the PH group was confirmed to be positively correlated with the increase in the levels of IL-6 and 8-iso-PSG in both EBC and serum （r=0.477-0.589, P 〈0.05）. Conclusion The increase in the levels of IL-6 and 8-iso-PSG in EBC and serum correlates with the pathogenesis of PH in COPD.展开更多
基金This work was partially funded by the National Institutes of Health NIEHS Center Grant ES005022 and by the Rutgers University Electrical and Computer Engineering Department.
文摘We present a portable non-invasive approach for measuring indicators of inflammation and oxidative stress in the respiratory tract by quantifying a biomarker in exhaled breath condensate(EBC).We discuss the fabrication and characterization of a miniaturized electrochemical sensor for detecting nitrite content in EBC using reduced graphene oxide.The nitrite content in EBC has been demonstrated to be a promising biomarker of inflammation in the respiratory tract,particularly in asthma.We utilized the unique properties of reduced graphene oxide(rGO);specifically,the material is resilient to corrosion while exhibiting rapid electron transfer with electrolytes,thus allowing for highly sensitive electrochemical detection with minimal fouling.Our rGO sensor was housed in an electrochemical cell fabricated from polydimethyl siloxane(PDMS),which was necessary to analyze small EBC sample volumes.The sensor is capable of detecting nitrite at a low over-potential of 0.7 V with respect to an Ag/AgCl reference electrode.We characterized the performance of the sensors using standard nitrite/buffer solutions,nitrite spiked into EBC,and clinical EBC samples.The sensor demonstrated a sensitivity of 0.21μAμM^(−1) cm^(−2) in the range of 20–100μM and of 0.1μAμM^(−1) cm^(−2) in the range of 100–1000μM nitrite concentration and exhibited a low detection limit of 830 nM in the EBC matrix.To benchmark our platform,we tested our sensors using seven pre-characterized clinical EBC samples with concentrations ranging between 0.14 and 6.5μM.This enzyme-free and label-free method of detecting biomarkers in EBC can pave the way for the development of portable breath analyzers for diagnosing and managing changes in respiratory inflammation and disease.
文摘2009186 The clinical significance of noninvasive inflammatory markers in exhaled breath condensate and induced sputum in persistent asthmatic patients. TAN Chengwu(谭成戊),et al.Dept Respir Med,West China Hosp,Sichuan Univ,Chengdu,Sichuan 610041.Chin J Interm Med,2009;48(4):299-303.
文摘Background Pulmonary hypertension （PH） is a common complication of chronic obstructive pulmonary disease （COPD）. Although alveolar hypoxia is considered as a main cause of PH in COPD, structural and functional changes of pulmonary circulation are apparent at the initial stage of COPD. We hypothesized that an inflammatory response and oxidative stress might contribute to the formation of PH in COPD. Methods We measured the levels of interleukin-6 （IL-6） and 8-iso-prostaglandin （8-iso-PSG） in exhaled breath condensate （EBC） and serum in 40 patients with COPD only or in 45 patients with COPD combined with PH. Pulmonary arterial systolic pressure （PASP） was assessed by Doppler echocardiography and defined as PH when the value of systolic pressure was greater than 40 mmHg. Results Compared with the COPD only group, the level of IL-6 in EBC was significantly increased in all 45 patients with COPD combined with PH （（8.27±2.14） ng/L vs. （4.95±1.19） ng/L, P 〈0.01）. The level of IL-6 in serum was also elevated in patients with COPD combined with PH compared with the COPD only group （（72.8±21.6） ng/L vs. （43.58±13.38） ng/L, P 〈0.01 ）. Similarly, we also observed a significant increase in the level of 8-iso-PSG in both EBC and serum in the COPD with PH group, compared with the COPD only group （EBC： （9.00±2.49） ng/L vs. （5.96±2.31） ng/L, P 〈0.01 and serum： （41.87±9.75） ng/L vs. （27.79±11.09） ng/L, P 〈0.01）. Additionally, the value of PASP in the PH group was confirmed to be positively correlated with the increase in the levels of IL-6 and 8-iso-PSG in both EBC and serum （r=0.477-0.589, P 〈0.05）. Conclusion The increase in the levels of IL-6 and 8-iso-PSG in EBC and serum correlates with the pathogenesis of PH in COPD.
