Umbilical cord mesenchymal stem cells (UC-MSCs) have been widely used in regenerative medicine, but there is limited research on the stability of UC-MSCs formulation during production. This study aims to assess the stability of the cell stock solution and intermediate product throughout the production process, as well as the final product following reconstitution, in order to offer guidance for the manufacturing process and serve as a reference for formulation reconstitution methods. Three batches of cell formulation were produced and stored under low temperature (2-8 ℃) and room temperature (20-26 ℃) during cell stock solution and intermediate product stages. The storage time intervals for cell stock solution were 0, 2, 4, and 6 h, while for intermediate products, the intervals were 0, 1, 2, and 3 h. The evaluation items included visual inspection, viable cell concentration, cell viability, cell surface markers, lymphocyte proliferation inhibition rate, and sterility. Additionally, dilution and culture stability studies were performed after reconstitution of the cell product. The reconstitution diluents included 0.9% sodium chloride injection, 0.9% sodium chloride injection + 1% human serum albumin, and 0.9% sodium chloride injection + 2% human serum albumin, with dilution ratios of 10-fold and 40-fold. The storage time intervals after dilution were 0, 1, 2, 3, and 4 h. The reconstitution culture media included DMEM medium, DMEM + 2% platelet lysate, 0.9% sodium chloride injection, and 0.9% sodium chloride injection + 1% human serum albumin, and the culture duration was 24 h. The evaluation items were viable cell concentration and cell viability. The results showed that the cell stock solution remained stable for up to 6 h under both low temperature (2-8 ℃) and room temperature (20-26 ℃) conditions, while the intermediate product remained stable for up to 3 h under the same conditions. After formulation reconstitution, using sodium chloride injection diluted with 1% or 2% human serum albumin maintained a viability of over 80% within 4 h. It was observed that different dilution factors had an impact on cell viability. After formulation reconstitution, cultivation in medium with 2% platelet lysate resulted in a cell viability of over 80% after 24 h. In conclusion, the stability of cell stock solution within 6 h and intermediate product within 3 h meets the requirements. The addition of 1% or 2% human serum albumin in the reconstitution diluent can better protect the post-reconstitution cell viability.

ObjectiveTo analyze the long-term trends of the disease burden of diabetes attributed to metabolic factors in China from 1990 to 2019, and provide scientific recommendations for diabetes prevention and control in China. MethodsDescriptive analysis was conducted on the disease burden data of diabetes attributed to metabolic factors in China from 1990 to 2019, obtained from GBD 2019, encompassing death form diabetes, disability-adjusted life years (DALY), years of life lost (YLL), and years lived with disability (YLD). Joinpoint regression models were employed to analyze the long-term trends in mortality and DALY rates. Furthermore, the study examined the impact of two metabolic risk factors, high fasting plasma glucose (FPG) levels and high body mass index (BMI) levels, on the disease burden of diabetes. ResultsFrom 1990 to 2019, the overall standardized mortality and DALY rates attributed to metabolic factors for diabetes in the general population in China showed an upward trend, with both average annual percent changes (AAPCs) of 0.1% in the total population. The trend was upward in males with AAPCs of 0.9% and 0.6%, while it was downward in females with AAPCs of -0.4% and -0.3%. As age increased, the disease burden of diabetes attributed to metabolic factors showed an upward trend, with high FPG and high BMI ranking as the top two attributing risk factors. The disease burden of diabetes attributed to metabolic factors was higher in Chinese males than females. ConclusionThe disease burden of diabetes attributed to metabolic factors is increasing among the overall population and particularly among males, while the burden for female is declining. There is a need to increase intervention efforts for males aged 65 and above, provide scientific guidance on residents’ diet and lifestyle habits, and control blood glucose and body weight.

Objective:To investigate the effect of nuclear factor E2-related factor 2 (Nrf2) protein on ferroptosis in mice with sepsis-associated liver injury (SALI).Methods:The male Sprague-Dawley (SD) mice were divided into 6 groups according to the random number table method, with 6 mice in each group. The SALI model of mice was established by cecal ligation and puncture (CLP), and the Sham group was only treated with laparotomy. CLP+Fer-1 group, CLP+Erastin group, CLP+ML385 group and CLP+Curcumin group were intraperitoneally injected with iron death inhibitor Ferrostatin-1 (Fer-1) 10 mg·kg -1·d -1, iron death activator Erastin 20 mg·kg -1·d -1, Nrf2 inhibitor ML385 30 mg·kg -1·d -1 and Nrf2 activator Curcumin 100 mg·kg -1·d -1 after CLP, respectively; Sham group and CLP group were given normal saline 10 mg·kg -1·d -1, each group was administered continuously for 10 days. Ten days after operation, the serum and liver tissues of mice were collected to detect the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in serum, and the levels of malondialdehyde (MDA), glutathione (GSH) and Fe 2+ in liver homogenate. The pathological changes of liver tissue were observed under light microscope after hematoxylin-eosin (HE) staining. The shape and length of mitochondria in liver cells were observed under transmission electron microscope. The protein expressions of Nrf2, glutathione peroxidase 4 (GPX4) and prostaglandin-endoperoxide synthase 2 (PTGS2) in liver tissue were detected by Western blotting. Results:Compared with Sham group, the serum levels of ALT and AST in the CLP group were significantly increased; histologically, the hepatic cord was disordered, the cells were swollen and necrotic, and the length of mitochondria was significantly shortened; the levels of MDA and Fe 2+ in liver tissue increased significantly, and the content of GSH decreased significantly; the protein expressions of Nrf2 and GPX4 in liver tissue decreased, and the protein expression of PTGS2 increased significantly. Compared with CLP group, the serum levels of ALT and AST in CLP+Fer-1 group and CLP+Curcumin group were significantly decreased [ALT (U/L): 80.65±19.44, 103.45±20.52 vs. 283.50±37.12, AST (U/L): 103.33±11.90, 127.33±15.79 vs. 288.67±36.82, all P < 0.05]; microscopically, the hepatic cord was irregular, the cells were slightly swollen, and the mitochondrial length was significantly increased (μm: 1.42±0.09, 1.43±0.21 vs. 1.07±0.25, both P < 0.05); the levels of MDA and Fe 2+ in liver tissue decreased significantly, and the content of GSH increased significantly [MDA (mol/g): 0.87±0.23, 1.85±0.43 vs. 4.47±0.95, Fe 2+ (μg/g): 63.80±7.15, 67.48±6.28 vs. 134.52±14.32, GSH (mol/g): 1.95±0.29, 1.95±0.45 vs. 0.55±0.29, all P < 0.05]; the protein expressions of Nrf2 and GPX4 in liver tissue were significantly increased, and the protein expression of PTGS2 was significantly decreased (Nrf2/GAPDH: 1.80±0.28, 2.10±0.43 vs. 0.70±0.24, GPX4/GAPDH: 0.80±0.06, 0.93±0.07 vs. 0.48±0.02, PTGS2/GAPDH: 0.76±0.05, 0.84±0.01 vs. 1.02±0.09, all P < 0.05). However, the results of the above indexes in the CLP+Erastin group and CLP+ML385 group were opposite, and the serum levels of ALT and AST were significantly increased [ALT (U/L): 344.52±40.79, 321.70±21.10 vs. 283.50±37.12, AST (U/L): 333.50±27.90, 333.00±16.67 vs. 288.67±36.82, all P < 0.05]; microscopically, the arrangement of hepatic cords was disordered, the cells were obviously swollen and necrotic, and the length of mitochondria was significantly shortened (μm: 0.78±0.13, 0.67±0.07 vs. 1.07±0.25, both P < 0.05); the levels of MDA and Fe 2+ in liver tissue increased significantly, and the content of GSH decreased significantly [MDA (mol/g): 5.92±1.06, 5.62±0.56 vs. 4.47±0.95, Fe 2+ (μg/g): 151.40±8.03, 151.88±8.68 vs. 134.52±14.32, GSH (mol/g): 0.25±0.08, 0.23±0.11 vs. 0.55±0.29, all P < 0.05]; the protein expressions of Nrf2 and GPX4 in liver tissue were significantly decreased, and the protein expression of PTGS2 was significantly increased (Nrf2/GAPDH: 0.46±0.09, 0.46±0.11 vs. 0.70±0.24, GPX4/GAPDH: 0.34±0.05, 0.40±0.01 vs. 0.48±0.02, PTGS2/GAPDH: 1.24±0.13, 1.16±0.11 vs. 1.02±0.09, all P < 0.05). Conclusion:CLP-induced SALI can lead to ferroptosis in mice hepatocytes, and Nrf2 protein in liver tissue can mediate SALI by regulating ferroptosis.

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

Objective: To identify the main metals involved in cognitive impairment in the Chinese oldest old, and explore the association between these metal exposures and cognitive impairment. Methods: A cross-sectional study was conducted on 1 568 participants aged 80 years and older from Healthy Aging and Biomarkers Cohort Study (2017 to 2018). Fasting venous blood was collected to measure the levels of nine metals (selenium, lead, cadmium, arsenic, antimony, chromium, manganese, mercury, and nickel). The cognitive function of these participants was evaluated by using the Chinese version of the Mini-Mental State Examination (CMMSE). The random forest (RF) was applied to independently identify the main metals that affected cognitive impairment. The multivariate logistic regression model and restricted cubic splines (RCS) model were used to further verify the association of the main metals with cognitive impairment. Results: The age of 1 568 study subjects was (91.8±7.6) years old, including 912 females (58.2%) and 465 individuals (29.7%) with cognitive function impairment. Based on the RF model (the out-of-bag error rate was 22.9%), the importance ranking of variables was conducted and the feature screening of five times ten-fold cross-validation was carried out. It was found that selenium was the metal that affected cognitive function impairment, and the other eight metals were not included in the model. After adjusting for covariates, the multivariate logistic regression model showed that with every increase of 10 μg/L of blood selenium levels, the risk of cognitive impairment decreased (OR=0.921, 95%CI: 0.889-0.954). Compared with the lowest quartile(Q₁) of blood selenium, the ORs (95%CI) of Q₃ and Q₄ blood selenium were 0.452 (0.304-0.669) and 0.419 (0.281-0.622) respectively. The RCS showed a linear dose-response relationship between blood selenium and cognitive impairment (P_nonlinear>0.05). Conclusion: Blood selenium is negatively associated with cognitive impairment in the Chinese oldest old.
Aged, 80 and over ; Female ; Humans ; Selenium ; Cohort Studies ; Cross-Sectional Studies ; Metals/analysis* ; Cognitive Dysfunction/epidemiology* ; China/epidemiology*

Humans ; Lymphangioma/surgery* ; Female ; Breast Neoplasms

Objectives: To investigated the safety and efficacy of treating patients with acute non-ST-segment elevation myocardial infarction (NSTEMI) and elevated levels of N-terminal pro-hormone B-type natriuretic peptide (NT-proBNP) with levosimendan within 24 hours of first medical contact (FMC). Methods: This multicenter, open-label, block-randomized controlled trial (NCT03189901) investigated the safety and efficacy of levosimendan as an early management strategy of acute heart failure (EMS-AHF) for patients with NSTEMI and high NT-proBNP levels. This study included 255 patients with NSTEMI and elevated NT-proBNP levels, including 142 males and 113 females with a median age of 65 (58-70) years, and were admitted in the emergency or outpatient departments at 14 medical centers in China between October 2017 and October 2021. The patients were randomly divided into a levosimendan group (n=129) and a control group (n=126). The primary outcome measure was NT-proBNP levels on day 3 of treatment and changes in the NT-proBNP levels from baseline on day 5 after randomization. The secondary outcome measures included the proportion of patients with more than 30% reduction in NT-proBNP levels from baseline, major adverse cardiovascular events (MACE) during hospitalization and at 6 months after hospitalization, safety during the treatment, and health economics indices. The measurement data parameters between groups were compared using the t-test or the non-parametric test. The count data parameters were compared between groups using the χ² test. Results: On day 3, the NT-proBNP levels in the levosimendan group were lower than the control group but were statistically insignificant [866 (455, 1 960) vs. 1 118 (459, 2 417) ng/L, Z=-1.25,P=0.21]. However, on day 5, changes in the NT-proBNP levels from baseline in the levosimendan group were significantly higher than the control group [67.6% (33.8%,82.5%)vs.54.8% (7.3%,77.9%), Z=-2.14, P=0.03]. There were no significant differences in the proportion of patients with more than 30% reduction in the NT-proBNP levels on day 5 between the levosimendan and the control groups [77.5% (100/129) vs. 69.0% (87/126), χ²=2.34, P=0.13]. Furthermore, incidences of MACE did not show any significant differences between the two groups during hospitalization [4.7% (6/129) vs. 7.1% (9/126), χ²=0.72, P=0.40] and at 6 months [14.7% (19/129) vs. 12.7% (16/126), χ²=0.22, P=0.64]. Four cardiac deaths were reported in the control group during hospitalization [0 (0/129) vs. 3.2% (4/126), P=0.06]. However, 6-month survival rates were comparable between the two groups (log-rank test, P=0.18). Moreover, adverse events or serious adverse events such as shock, ventricular fibrillation, and ventricular tachycardia were not reported in both the groups during levosimendan treatment (days 0-1). The total cost of hospitalization [34 591.00(15 527.46,59 324.80) vs. 37 144.65(16 066.90,63 919.00)yuan, Z=-0.26, P=0.80] and the total length of hospitalization [9 (8, 12) vs. 10 (7, 13) days, Z=0.72, P=0.72] were lower for patients in the levosimendan group compared to those in the control group, but did not show statistically significant differences. Conclusions: Early administration of levosimendan reduced NT-proBNP levels in NSTEMI patients with elevated NT-proBNP and did not increase the total cost and length of hospitalization, but did not significantly improve MACE during hospitalization or at 6 months.
Male ; Female ; Humans ; Aged ; Natriuretic Peptide, Brain ; Simendan/therapeutic use* ; Non-ST Elevated Myocardial Infarction ; Heart Failure/drug therapy* ; Peptide Fragments ; Arrhythmias, Cardiac ; Biomarkers ; Prognosis

Objective: This cross-sectional investigation aimed to determine the incidence, clinical characteristics, prognosis, and related risk factors of olfactory and gustatory dysfunctions related to infection with the SARS-CoV-2 Omicron strain in mainland China. Methods: Data of patients with SARS-CoV-2 from December 28, 2022, to February 21, 2023, were collected through online and offline questionnaires from 45 tertiary hospitals and one center for disease control and prevention in mainland China. The questionnaire included demographic information, previous health history, smoking and alcohol drinking, SARS-CoV-2 vaccination, olfactory and gustatory function before and after infection, other symptoms after infection, as well as the duration and improvement of olfactory and gustatory dysfunction. The self-reported olfactory and gustatory functions of patients were evaluated using the Olfactory VAS scale and Gustatory VAS scale. Results: A total of 35 566 valid questionnaires were obtained, revealing a high incidence of olfactory and taste dysfunctions related to infection with the SARS-CoV-2 Omicron strain (67.75%). Females(χ2=367.013, P<0.001) and young people(χ2=120.210, P<0.001) were more likely to develop these dysfunctions. Gender(OR=1.564, 95%CI: 1.487-1.645), SARS-CoV-2 vaccination status (OR=1.334, 95%CI: 1.164-1.530), oral health status (OR=0.881, 95%CI: 0.839-0.926), smoking history (OR=1.152, 95%CI=1.080-1.229), and drinking history (OR=0.854, 95%CI: 0.785-0.928) were correlated with the occurrence of olfactory and taste dysfunctions related to SARS-CoV-2(above P<0.001). 44.62% (4 391/9 840) of the patients who had not recovered their sense of smell and taste also suffered from nasal congestion, runny nose, and 32.62% (3 210/9 840) suffered from dry mouth and sore throat. The improvement of olfactory and taste functions was correlated with the persistence of accompanying symptoms(χ2=10.873, P=0.001). The average score of olfactory and taste VAS scale was 8.41 and 8.51 respectively before SARS-CoV-2 infection, but decreased to3.69 and 4.29 respectively after SARS-CoV-2 infection, and recovered to 5.83and 6.55 respectively at the time of the survey. The median duration of olfactory and gustatory dysfunctions was 15 days and 12 days, respectively, with 0.5% (121/24 096) of patients experiencing these dysfunctions for more than 28 days. The overall self-reported improvement rate of smell and taste dysfunctions was 59.16% (14 256/24 096). Gender(OR=0.893, 95%CI: 0.839-0.951), SARS-CoV-2 vaccination status (OR=1.334, 95%CI: 1.164-1.530), history of head and facial trauma(OR=1.180, 95%CI: 1.036-1.344, P=0.013), nose (OR=1.104, 95%CI: 1.042-1.171, P=0.001) and oral (OR=1.162, 95%CI: 1.096-1.233) health status, smoking history(OR=0.765, 95%CI: 0.709-0.825), and the persistence of accompanying symptoms (OR=0.359, 95%CI: 0.332-0.388) were correlated with the recovery of olfactory and taste dysfunctions related to SARS-CoV-2 (above P<0.001 except for the indicated values). Conclusion: The incidence of olfactory and taste dysfunctions related to infection with the SARS-CoV-2 Omicron strain is high in mainland China, with females and young people more likely to develop these dysfunctions. Active and effective intervention measures may be required for cases that persist for a long time. The recovery of olfactory and taste functions is influenced by several factors, including gender, SARS-CoV-2 vaccination status, history of head and facial trauma, nasal and oral health status, smoking history, and persistence of accompanying symptoms.
Female ; Humans ; Adolescent ; SARS-CoV-2 ; Smell ; COVID-19/complications* ; Cross-Sectional Studies ; COVID-19 Vaccines ; Incidence ; Olfaction Disorders/etiology* ; Taste Disorders/etiology* ; Prognosis

Objective: To analyze the prevalence and the risk factors of fungal sepsis in 25 neonatal intensive care units (NICU) among preterm infants in China, and to provide a basis for preventive strategies of fungal sepsis. Methods: This was a second-analysis of the data from the "reduction of infection in neonatal intensive care units using the evidence-based practice for improving quality" study. The current status of fungal sepsis of the 24 731 preterm infants with the gestational age of <34⁺⁰ weeks, who were admitted to 25 participating NICU within 7 days of birth between May 2015 and April 2018 were retrospectively analyzed. These preterm infants were divided into the fungal sepsis group and the without fungal sepsis group according to whether they developed fungal sepsis to analyze the incidences and the microbiology of fungal sepsis. Chi-square test was used to compare the incidences of fungal sepsis in preterm infants with different gestational ages and birth weights and in different NICU. Multivariate Logistic regression analysis was used to study the outcomes of preterm infants with fungal sepsis, which were further compared with those of preterm infants without fungal sepsis. The 144 preterm infants in the fungal sepsis group were matched with 288 preterm infants in the non-fungal sepsis group by propensity score-matched method. Univariate and multivariate Logistic regression analysis were used to analyze the risk factors of fungal sepsis. Results: In all, 166 (0.7%) of the 24 731 preterm infants developed fungal sepsis, with the gestational age of (29.7±2.0) weeks and the birth weight of (1 300±293) g. The incidence of fungal sepsis increased with decreasing gestational age and birth weight (both P<0.001). The preterm infants with gestational age of <32 weeks accounted for 87.3% (145/166). The incidence of fungal sepsis was 1.0% (117/11 438) in very preterm infants and 2.0% (28/1 401) in extremely preterm infants, and was 1.3% (103/8 060) in very low birth weight infants and 1.7% (21/1 211) in extremely low birth weight infants, respectively. There was no fungal sepsis in 3 NICU, and the incidences in the other 22 NICU ranged from 0.7% (10/1 397) to 2.9% (21/724), with significant statistical difference (P<0.001). The pathogens were mainly Candida (150/166, 90.4%), including 59 cases of Candida albicans and 91 cases of non-Candida albicans, of which Candida parapsilosis was the most common (41 cases). Fungal sepsis was independently associated with increased risk of moderate to severe bronchopulmonary dysplasia (BPD) (adjusted OR 1.52, 95%CI 1.04-2.22, P=0.030) and severe retinopathy of prematurity (ROP) (adjusted OR 2.55, 95%CI 1.12-5.80, P=0.025). Previous broad spectrum antibiotics exposure (adjusted OR=2.50, 95%CI 1.50-4.17, P<0.001), prolonged use of central line (adjusted OR=1.05, 95%CI 1.03-1.08, P<0.001) and previous total parenteral nutrition (TPN) duration (adjusted OR=1.04, 95%CI 1.02-1.06, P<0.001) were all independently associated with increasing risk of fungal sepsis. Conclusions: Candida albicans and Candida parapsilosis are the main pathogens of fungal sepsis among preterm infants in Chinese NICU. Preterm infants with fungal sepsis are at increased risk of moderate to severe BPD and severe ROP. Previous broad spectrum antibiotics exposure, prolonged use of central line and prolonged duration of TPN will increase the risk of fungal sepsis. Ongoing initiatives are needed to reduce fungal sepsis based on these risk factors.
Infant ; Infant, Newborn ; Humans ; Birth Weight ; Intensive Care Units, Neonatal ; Retrospective Studies ; Tertiary Care Centers ; Infant, Extremely Low Birth Weight ; Gestational Age ; Infant, Extremely Premature ; Sepsis/epidemiology* ; Retinopathy of Prematurity/epidemiology* ; Bronchopulmonary Dysplasia/epidemiology*

OBJECTIVE: Late 2019 witnessed the outbreak and widespread transmission of coronavirus disease 2019 (COVID-19), a new, highly contagious disease caused by novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Consequently, considerable attention has been paid to the development of new diagnostic tools for the early detection of SARS-CoV-2. METHODS: In this study, a new poly-N-isopropylacrylamide microgel-based electrochemical sensor was explored to detect the SARS-CoV-2 spike protein (S protein) in human saliva. The microgel was composed of a copolymer of N-isopropylacrylamide and acrylic acid, and gold nanoparticles were encapsulated within the microgel through facile and economical fabrication. The electrochemical performance of the sensor was evaluated through differential pulse voltammetry. RESULTS: Under optimal experimental conditions, the linear range of the sensor was 10 ^-13-10 ^-9 mg/mL, whereas the detection limit was 9.55 fg/mL. Furthermore, the S protein was instilled in artificial saliva as the infected human saliva model, and the sensing platform showed satisfactory detection capability. CONCLUSION The sensing platform exhibited excellent specificity and sensitivity in detecting spike protein, indicating its potential application for the time-saving and inexpensive detection of SARS-CoV-2.
Humans ; Microgels ; Spike Glycoprotein, Coronavirus ; COVID-19/diagnosis* ; Gold ; Metal Nanoparticles ; SARS-CoV-2