How to process synovial fluid samples of gouty arthritis and extract its exosomes for subsequent cytokine analysis.

BACKGROUND: The comparative analysis of ultracentrifugation (UC) and polyethylene glycol (PEG)-based precipitation for the isolation of exosomes in gouty arthritis synovial fluid (GASF) is rarely reported, and it is not known whether different isolation methods can influence subsequent cytokine analysis. METHODS: GA patients were enrolled during a 1-year period from May 2021 to May 2022. Morphology, particle number, size, purity, protein concentration, and biomarker proteins of GASF-derived exosomes in both extraction methods were observed using transmission electron microscopy, nanoparticle tracer analysis, bicinchoninic acid assay, and Western blotting. An ELISA-based assay platform was used to detect the cytokines in exosomes using Meso Scale Discovery. RESULTS: Thirty-two cases of fresh GASF were taken and randomly divided between the UC group (n = 16) and the PEG group (n = 16). Transmission electron microscopy images and nanoparticle tracer analysis results showed round vesicles measuring 100 nm on average. The protein expressions of TSG101, CD63, and CD81 in exosomes of the 2 groups were measured via Western blotting. The number and protein concentration of GASF-derived exosome particles from the PEG group were significantly higher than that of the UC group (P < .001). However, in the purity estimation, the UC group reflected significantly higher exosomes extractability (P < .01). Expression of IL-6 and IL-8 in the GASF-derived exosomes were higher in the UC group (P < .05), showing a median of 3.31 (interquartile range, IQR: 0.84-13.16) pg/mL, and a median of 2.87 (IQR: 0.56-13.17) pg/mL, respectively; moreover, IL-1ß was mostly undetectable in the PEG group. CONCLUSION: The UC method was found to yield exosomes of a higher purity, albeit at a lower quantity but with more abundant inflammatory cytokines; whereas the opposite was the case for the PEG group. The chemical precipitation method might not be suitable in terms of extracting GASF-derived exosomes for inflammation and immunity studies.

Acupoint application therapy for diarrhea-predominant irritable bowel syndrome: a protocol for systematic review and network meta-analysis.

BACKGROUND: Irritable bowel syndrome is a chronic functional gastrointestinal disease, of which diarrhea-predominant irritable bowel syndrome (IBS-D) is a common subtype. In China, acupoint application therapy is currently widely used as an effective complementary therapy for IBS-D. In the clinical management of IBS-D, acupoint application is usually combined with other therapies, including acupuncture, moxibustion, and Chinese herbal and Western medicine. However, at present, evidence regarding the most effective options for treating IBS-D is insufficient. Therefore, this protocol proposes a systematic review and network meta-analysis for evaluating the effectiveness of acupoint application and its combination therapies in treating IBS-D, and for identifying the acupoint application-related treatments with the highest probability of being the best intervention. METHODS: Six English electronic databases (PubMed, Ovid MEDLINE, Scopus, Web of Science, the Cochrane Library, and EMBASE), four Chinese electronic databases [China National Knowledge Infrastructure (CNKI), China Science and Technology Journal Database (CQVIP), WanFang, and SinoMed), and one Japanese medical database (Citation Information by National Institute of Informatics (CiNii)] will be searched for eligible randomized controlled trials from their inception to June 1, 2022. The efficacy and safety of acupoint application therapy and its combination therapies for patients with IBS-D will be evaluated. The STATA 14.0 (StataCorp, USA) software package will be used for the meta-analysis. A Bayesian network meta-analysis (NMA) will be performed using R (version 4.0.2) and Aggregate Data Drug Information System (ADDIS, version 1.16.8) software packages. Bias risk will be assessed using the Cochrane Collaboration's risk of bias tool; specifically, publication bias will be evaluated using Egger's test and funnel plots. The rank probabilities of various outcomes for each intervention will be calculated, clustered, and ranked using the cumulative ranking curve method. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) method will be employed to assess the certainty of evidence for NMA outcomes. CONCLUSIONS: This study will aim to determine the clinical efficacy of acupoint application therapy and its combined therapy in the treatment of IBS-D and provide an evidence-based foundation for identifying the best acupoint application program.

Amine organocatalysts for highly ortho-selective chlorination of anilines with sulfuryl chloride.

A metal catalyst free approach for regioselective ortho-chlorination of anilines has been developed using a secondary amine as the organocatalyst and sulfuryl chloride as the halogen source under mild conditions. A wide range of substrates were compatible with this catalytic system. In addition, this catalytic protocol has been applied to the efficient synthesis of bioactive compounds and modification of drug derivatives. Further studies indicated that the anionic trichloride species was responsible for the ortho-selectivity.

Is Chinese herbal formula (nourishing Yin therapy) effective and well tolerated as an adjunct medication to hydroxychloroquine in the treatment of primary Sjögren's syndrome? A meta-analysis of randomised controlled trials.

BACKGROUND: Previously, data mining methodology was used to identify 71 patented prescriptions in Chinese patent databases, indicating that Yin-nourishing therapy (YNT) may be an adjunct medication to hydroxychloroquine in the treatment of primary Sjögren's syndrome (pSS). The purpose of this study was to investigate effects of the addition of YNT, which includes tonifying liver and kidney therapy (TLKT) and replenishing Qi and nourishing Yin therapy (RQNYT), in the treatment of pSS. METHODS: Fourteen databases (including Chinese, English, Japanese, Korean and Latin databases) were searched to identify randomised controlled trials (RCTs) of YNT plus hydroxychloroquine (YNTPH) versus hydroxychloroquine alone in patients with pSS. Relevant publications up to June 2021 were selected. A meta-analysis and trial sequential analysis (TSA) were performed using Review Manager 5.3, Stata 14.0 and TSA 0.9 software. The quality of identified studies was assessed based on the Cochrane risk of bias tool and GRADE (grading of recommendations, assessment, development and evaluation) criteria. RESULTS: We included five RCTs with a total of 345 participants. Pooled results indicated significant differences in short-term outcomes, which were assessed via European League Against Rheumatism (EULAR) Sjögren's Syndrome Patient Reported Index (ESSPRI), EULAR Sjögren's Syndrome Disease Activity Index (ESSDAI), tear production, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and immunoglobulin G (IgG) results when YNTPH was compared with hydroxychloroquine use alone (p < 0.05). No significant difference in salivary flow rate was reported. The most common side effect reported for both groups was gastrointestinal reaction. Sensitivity analyses suggested that heterogeneity might be ascribed to clinical methodology. Subgroup analyses revealed heterogeneities regarding salivary flow rate were eliminated. TLKT appeared to be better than RQNYT for improving salivary flow rate. TSA only supported changes in ESSPRI, ESSDAI and ESR values. For all studies, the quality of evidence was low. CONCLUSION: YNTPH may be an effective complementary therapy. Current evidence, however, is insufficient for determining whether YNTPH is more effective than hydroxychloroquine alone. Well-designed RCTs are needed to determine the role of YNT in pSS treatment.

Comparative efficacy and safety of four classical prescriptions for clearing damp-heat recommended by clinical guidelines in treating rheumatoid arthritis: a network meta-analysis.

BACKGROUND: In China, along with conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs), some herbal formulae for clearing damp-heat are widely applied in treating rheumatoid arthritis (RA). We aimed to summarize and compare the clinical effects of 4 guideline-recommended formulae, including Baihuguizhi decoction, Dangguiniantong decoction, Simiao pill, and Xuanbi decoction. METHODS: PubMed, Cochrane Library, EMBASE, Chinese National Knowledge Infrastructure (CNKI), Chinese Science and Technique Journals (CQVIP), WanFang, and SinoMed (CBM) databases were searched for randomized controlled trials from inception to July 2020 evaluating the efficacy and safety of these recommended herbal formulae combined with 1 csDMARD versus csDMARD alone in RA patients. A pairwise meta-analysis was conducted in RevMan 5.3 software, and a Bayesian network meta-analysis (NMA) was performed with Stata 14.0, R 4.0.2, GeMTC 0.14.3, and JAGS 4.3.0 software. Cochrane Handbook 5.1.0 was used to assess the risk of bias. Publication bias was evaluated using Egger's test, the trim-fill adjustment, and funnel plots. Trial sequential analysis (TSA) was performed to validate the overall results. The rank probability of interventions was calculated and clustered by the surface under the cumulative ranking curve (SUCRA). Pharmacologic actions of formulae were explored through the network pharmacology approach. RESULTS: A total of 15 studies, including 1,079 individuals, were identified. Simiao pill + csDMARD [SMPPD, odds ratio (OR) =6.62, 95% confidence interval (CI): 2.88 to 16.84] was superior to csDMARDs alone in clinical efficiency, and was more able to reduce C-reactive protein and erythrocyte sedimentation rate levels [mean difference (MD) =-7.91, 95% CI: -17.41 to -1.25; MD =-9.31, 95% CI: -14.48 to -5.56 respectively]. Although publication bias was observed (P=0.033), the trim-fill method indicated that the pooled values kept stable. Fewer adverse events (AEs) were shown with SMPPD (6.45%). TSA confirmed the results of efficacy rate at SMPPD. Network pharmacology included 5 common components and 66 common targets among 4 formulae in treating RA, involving regulating immunity and relieving inflammation. DISCUSSION: SMPPD might be a preferable complementary therapy for RA. However, considering the limitations of this study, recommendations for clinical practice should be validated by the results of further well-designed studies.

Adoption of a new gait system to evaluate the clinical effects of minimally invasive needle-knife scope therapy for the treatment of rheumatoid arthritis of the knee joint.

BACKGROUND: The purpose of this study was to use kinematic gait analysis, to evaluate the clinically curative effects of minimally invasive needle-knife scope therapy in the treatment of rheumatoid arthritis (RA) of the knee joint. METHODS: A total of 32 patients with RA of the knee joint were treated with minimally invasive needle-knife scope therapy. All patients were assessed with a kinematic gait analysis system, and then analyzed and compared the measurements with the kinematic gait performances of 28 healthy middle-aged and elderly participants. RESULTS: Before receiving the therapy, the ranges of motion (ROMs) of the patients' tibial inward and outward rotation, flexion and extension, anterior and posterior displacement of the tibia, and tibial upward and downward movement were all smaller than those of the healthy middle-aged and elderly group (P<0.05). After receiving the therapy, the patients' knees had a remarkably larger ROM. After one month of this therapy, they had a noticeably greater ROM in flexion and extension, tibial inward and outward rotation, and upward and downward movement of the tibia (P<0.05). After 1 month of therapy, the patients' maximum flexion angle and tibial posterior displacement angle were noticeably greater than beforehand (P<0.01). After 1 year of therapy, the patients' flexion and extension range became remarkably greater than it was after 1 month of the therapy (P<0.01). Their ranges of DOF reflected no apparent difference to the healthy middle-aged and elderly group, which remained smaller than the latter (P<0.05). After 1 year of therapy, the maximum values of the patients' flexion angle, tibial internal rotation angle, tibial posterior displacement angle, and tibial downward movement angle were remarkably higher than before commencing treatment (P<0.05). CONCLUSIONS: Minimally invasive needle-knife scope therapy enables a good recovery of function for patients with RA and remarkably improves the DOF of knees. Gait analyses are more objective, accurate, and quantitative than other indexes, and thus may become a new means to assess the changes in knee joint functions.

Long-term hydroxychloroquine therapy improves the quality of sleep in patients with primary Sjögren's syndrome: a real-world study.

BACKGROUND: Patients with primary Sjögren's syndrome (pSS) often suffer from sleep disturbance. Studies suggest it may be related to symptoms, including xerostomia and dry eyes. Clinical studies have confirmed that hydroxychloroquine (HCQ) has a definite effect on pSS, but there is no clear report about its effect on sleep disorders in pSS patients. METHODS: A total of 383 pSS patients were enrolled and followed up. The Pittsburgh Sleep Quality Index (PSQI) was used to evaluate the sleep quality of the patients, and the World Health Organization Quality of Life Brief Version (WHOQOL-BREF) scale was used to evaluate the quality of life (QoL) of patients. The European League assessed the patient's condition against Rheumatism Sjögren's syndrome patients reported index (ESSPRI). According to PSQI, patients were divided into two groups: good sleep group (GSG) and poor sleep group (PSG). The risk factors of sleep disorder are analyzed by univariate and multivariate analysis. The patients were further divided into HCQ-administered group and non-administered group, and the differences of baseline characteristics and outcome in follow-up between the two groups were compared. RESULTS: There were 208 patients with PSG (54.3%) and 175 patients with GSG (45.7%). Further, there is no statistical difference between the two groups in baseline data. Also, there were 112 cases (53.8%) and 118 cases (67.4%) taking HCQ in the two groups, respectively, P=0.007. Univariate and multivariate analysis showed that long-term use of HCQ, menopause, and income were related to sleep quality. The patients were divided into the HCQ-administered group (n=230) and non-administered group (n=153) according to whether they took HCQ. One hundred eighteen patients (51.3%) in the HCQ-administered group had a good sleep, and 58 patients in the non- administered group had a good sleep (37.9%), P<0.05. At followup, the PSQI of the two groups were 7.3±2.1 vs. 8.1±2.4, respectively, P<0.05 and the ESSPRI were 4.9±1.1 vs. 5.4±1.3, P<0.05. The QoL of the two groups of patients was statistically different in all four dimensions, P<0.05. CONCLUSIONS: Long-term use of HCQ can reduce the risk of sleep disturbance in patients with primary Sjögren's syndrome.

Distributive differences of P2Xs between the forelimb and hind limb of adjuvant arthritis rats and intervention by Notopterygh rhizoma et radix.

CONTEXT: Notopterygium incisum Ting ex H. T. Chang (Umbelliferae) (NI) specializes in treatment of upper limb rheumatoid arthritis (RA), but the exact mechanism is unclear. P2Xs are useful targets for inflammatory pain therapy. It led us to hypothesize that NI may preferentially act on particular P2Xs and these receptors may be unevenly distributed in the upper/lower limb. OBJECTIVE: To investigate P2Xs distribution in the upper/lower limb and NI's targets in upper limb RA. MATERIALS AND METHODS: The SD rats were randomized into 11 groups of 10 animals each. Eight experimental groups were established by the injection of 0.1 mL FCA into the plantar surface of rat paw. Three control groups suffered the same volume of saline. The articular cavities were then taken on the seventh day to detect P2Xs expression. NI (3 g/kg) and prednisone (10 mg/kg) were respectively given by oral gavage once daily for 14 d. The swelling degree and P2Xs were evaluated individually. RESULTS: In normal rats, the expressions of P2X3 and P2X6 in forelimb were markedly higher than that of in hind limb (P < 0.05). After induced by FCA, P2X1, P2X3, P2X4, P2X5 and P2X7 were increased significantly (P < 0.01). The biggest difference was P2X3. In NI treatment rats, swelling degree of the 7th/14th day in forelimb was 68.24%/38.89%, whereas that of in hind limb was 88.72%/79.92%. P2X3 mRNA and protein expression was significantly reduced as contrasted with the control group (P < 0.05). CONCLUSIONS: P2X3 receptor was predominantly expressed in the forelimb RA rat. NI relieved the FCA-induced RA by inhibiting upper limb's P2X3 receptor.

[Efficacy of fan-needle radiofrequency for knee osteoarthritis guided by meridians-muscles theory].

OBJECTIVE: To observe the efficacy difference between fan-needle radiofrequency guided by meridians-muscles theory and oral administration of medication for knee osteoarthritis (KOA). METHODS: One hundred patients with KOA were randomly divided into an acupuncture group and a medication group, 50 cases in each one. The patients in the acupuncture group were treated with fan-needle radiofrequency guided by meridians-muscles theory at tendon nodes around knee joints (ashi points), 4 points per treatment, once every two weeks and two treatments were given. The patients in the medication group were treated with oral administration of celecoxib capsules, 1 capsule every day for 4 weeks. The visual analogue scale (VAS) and Western Ontario and McMaster Universities (WOMAC) in the two groups were observed before treatment, after treatment and during 4-week follow-up visit. The clinical efficacy was evaluated. RESULTS: Compared before treatment, the VAS was reduced in the two groups after treatment and during 4-week follow-up visit (all P<0.05), and the VAS score in the acupuncture group was lower than that in the medication group (both P<0.05). Compared before treatment, the pain score, stiffness score, activity function score and total score of WOMAC were reduced in the two groups after treatment and during 4-week follow-up visit (all P<0.05), and the scores in the acupuncture group were lower than those in the medication group (all P<0.05). After treatment, the total effective rate was 80.0% (40/50) in the acupuncture group, which was superior to 56.0% (28/50) in the medication group (P<0.05). During 4-week follow-up visit, the total effective rate was 76.0% (38/50) in the acupuncture group, which was superior to 40.0% (20/50) in the medication group (P<0.05). CONCLUSION: The efficacy of fan-needle radiofrequency guided by meridians-muscles theory is superior to oral administration of celecoxib capsules for KOA, which could relieve joint pain and stiffness, improve joint mobility, and has long effective duration.

Herba Gelsemii elegantis is detoxified by ramulus et folium Mussaendae pubescentis extract by modulating hepatic cytochrome P450 and glutathione S-transferase enzymes in rats.

Herba Gelsemii elegantis (GE) has been frequently used as a Chinese folk medicine but has high acute toxicity. In Traditional Chinese Medicine, it may be detoxified by Ramulus et Folium Mussaendae pubescentis (MP), but the detoxification mechanism has remained elusive. The present study aimed to evaluate the detoxification mechanisms by which MP modulates the effect of GE in rats, including the inhibition of hepatic cytochrome P (CYP)450 and glutathione S-transferase (GST) enzymes. Male Sprague Dawley rats were orally administered GE at three doses (0.36, 0.43 or 0.54 g/kg) alone and, at the highest dose, in combination with MP (21.6 g/kg) every day for 7 consecutive days. The control group of animals received the same volume of saline. The mRNA and protein expression of hepatic CYPs representative of two subfamilies (CYP2E1 and CYP1A2) were separately assessed by reverse-transcription quantitative polymerase chain reaction (RT-qPCR), western blot and immunohistochemistry assays. The mRNA and protein expression as well as enzyme activity of hepatic GST were assessed by RT-qPCR, western blot and colorimetric assays, respectively. The results indicated that GE significantly inhibited CYP2E1 mRNA and protein expression in a dose-dependent manner. Co-administration of MP increased CYP2E1 mRNA and protein expression as compared with the high GE dose alone. Cells expressing CYP2E1, located around the hepatic vascular plexus under a clear background, were identified by immunohistochemical staining. The results for CYP1A2 were similar to those for CYP2E1. At all concentrations used, GE significantly inhibited GST mu 1 (GSTm1) mRNA and protein expression in a dose-dependent manner, as compared with the control. Combination of GE and MP increased the mRNA and protein expression of GSTm1 as compared with the high dose of GE. However, the differences in GST-pi mRNA and protein expression between the GE and GE + MP groups were not significant. Of note, rats co-treated with MP were significantly protected from the decrease in GST activity produced by GE. The present study indicated that co-administration of GE and MP upregulated the activities of CYP450 and GST enzymes when compared with GE alone. This modulation may explain for the effect of MP in reducing the acute toxicity of GE.

Meridian-sinew release therapy for the treatment of refractory rheumatoid arthritis.

OBJECTIVE: To evaluate the efficacy and safety of Meridian-sinew Release therapy in Chinese patients with refractory active Rheumatoid Arthritis (RA). SUMMARY OF BACKGROUND DATA: Few studies focused on the effect of combination of Meridian-sinew Release therapy and Methotrexate (MTX) on refractory active RA of Chinese patients. METHODS: Eighty refractory active rheumatoid arthritis patients were randomized to receive Meridian-sinew Release+MTX 10 mg (n=40), MTX 10 mg (n=40) every week for 12 weeks. The primary end point was the proportion of patients achieving ≥20% improvement in the American College of Rheumatology criteria (ACR20) at week 12. Secondary efficacy endpoints included 28-joint disease activity score with ESR (DAS28-ESR), simplified disease activity index (SDAI), clinical disease activity index (CDAI) and Health Assessment Questionnaire-Disability Index (HAQ-DI). RESULTS: Week 12 ACR20 response rates were significantly greater in Meridian-sinew Release+MTX group (30/38 (78.9%)) than in MTX group (19/37 (51.3%)), (P<0.001), as were ACR50 and ACR70 response rates. Patients treated with Meridian-sinew Release+MTX were significantly more likely to achieve clinical remission, using various definitions, at 12 weeks versus MTX alone. A larger percentage of Meridian-sinew+MTX patients than MTX alone patients were in states of low disease activity or remission for DAS28-ESR, SDAI and CDAI after 12 weeks of treatment. CONCLUSION: Our study suggests that Meridian-sinew Release therapy was well tolerated and efficacious in improving clinical outcomes in Chinese patients with refractory active RA.

[Treatment of Knee Osteoarthritis by Tendons of Minimally Invasive Therapy Combined Drug Ther- apy: a Clinical Observation of Sixty Cases].

OBJECTIVE: To assess the efficacy of tendons of minimally invasive therapy (TMIT) combined drug therapy by comparing it with treatment by drug therapy alone on patients with knee osteoarthritis (KOA). METHODS: Totally 60 KOA patients were assigned to the treatment group and the control group according to random digit table, 30 in each group. Patients in the control group took Hydrochloric Acid Glucosamine Capsule and Celecoxib Capsule. Patients in the treatment group additionally received TMIT. The treatment course for all was 4 weeks. Scores for visual analogue scale (VAS) and the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index were observed and recorded at week 1 and 4 after treatment by acupotomology mirror. RESULTS: Compared with before treatment, improvement was shown in VAS score, pain and stiffness degrees, activities and functions, and WOMAC scores at week 1 and 4 after treatment in all patients with statistical difference (P < 0.05). Besides, better effect was shown in the treatment group (P < 0.05). CONCLUSIONS: TMIT combined drug therapy could relieve KOA patients' pain, stiffness and joint activities, elevate the overall efficacy. TMIT was easily operated with less injury.

Evaluating meridian-sinew release therapy for the treatment of knee osteoarthritis.

Objective. In recent years, public health experts have concluded that the impact of osteoarthritis is equal in magnitude to that of cardiovascular disease. Osteoarthritis of the knee is prevalent in the elderly population; however, there are currently no effective treatments for this condition. In this study, we investigated the efficacy of "meridian-sinew release," a newly developed technique which entails using a meridian-sinew scope and a meridian-sinew knife to treat osteoarthritis of the knee. Methods. Patients (N = 90) with knee osteoarthritis were prospectively randomized to meridian-sinew release therapy, acupuncture therapy, or drug therapy groups, respectively. Outcome evaluation included pain, stiffness, physiological function, total symptom score, and overall changes in the condition. Results. After 12 weeks, patients' general assessment (GA) and doctors' general assessment (GA) of the condition were not significantly different among the three groups. However, significant differences in primary endpoint pain, joint stiffness, and total symptom score were found between the meridian-sinew group and the acupuncture group and between the meridian-sinew group and the control group (P < 0.05). No adverse events occurred during the trial. Conclusion. Our study suggests that meridian-sinew release therapy can improve knee osteoarthritis, alleviate joint pain, and improve functional movement disorder. It is a safe and effective treatment for knee osteoarthritis.

An electrochemiluminescent biosensor for glucose based on the electrochemiluminescence of luminol on the nafion/glucose oxidase/poly(nickel(II)tetrasulfophthalocyanine)/multi-walled carbon nanotubes modified electrode.

A poly(nickel(II) tetrasulfophthalocyanine)/multi-walled carbon nanotubes composite modified electrode (polyNiTSPc/MWNTs) was fabricated by electropolymerization of NiTSPc on MWNTs-modified glassy carbon electrode (GCE). The modified electrode was found to be able to greatly improve the emission of luminol electrochemiluminescence (ECL) in a solution containing hydrogen peroxide. Glucose oxidase (GOD) was immobilized on the surface of polyNiTSPc/MWNTs modified GC electrode by Nafion to establish an ECL glucose sensor. Under the optimum conditions, the linear response range of glucose was 1.0x10(-6) to 1.0x10(-4) mol L(-1) with a detection limit of 8.0x10(-8) mol L(-1) (defined as the concentration that could be detected at the signal-to-noise ratio of 3). The ECL sensor showed an outstanding well reproducibility and long-term stability. The established method has been applied to determine the glucose concentrations in real serum samples with satisfactory results.

An electrochemiluminescent biosensor for uric acid based on the electrochemiluminescence of bis-[3,4,6-trichloro-2-(pentyloxycarbonyl)-phenyl] oxalate on an ITO electrode modified by an electropolymerized nickel phthalocyanine film.

Nickel(ii) tetrasulfophthalo-cyanine (NiTSPc) could be electrodeposited onto an indium tin oxide (ITO) electrode to form an electropolymerization film of NiTSPc. The electrochemiluminescent (ECL) behavior of bis-[3,4,6-trichloro-2-(pentyloxy-carbonyl)-phenyl] oxalate (BTPPO) on this modified electrode was investigated in detail. The emission of ECL of BTPPO can be greatly enhanced by hydrogen peroxide at this modified electrode. Thus, a new ECL biosensor for uric acid was developed based on the enzymatic reaction of uric acid in the presence of uricase to produce H(2)O(2). The developed sensor has been used to detect uric acid in real serum samples, and the results compared well with those obtained by the routine method.

A new electrochemiluminescent sensing system for glucose based on the electrochemiluminescent reaction of bis-[3,4,6-trichloro-2-(pentyloxycarbonyl)-phenyl] oxalate.

In this paper, the electrochemiluminescence (ECL) behavior of bis-[3,4,6-trichloro-2-(pentyloxycarbonyl)-phenyl] oxalate (BTPPO) at glassy carbon electrode (GCE) in phosphate buffer solution in the presence of hydrogen peroxide has been investigated when linear sweep voltammetry was applied. The optimum chemical conditions and electrochemical parameters for this ECL system have been investigated in detail. Under the optimum conditions, it was found that the concentration of BTPPO was linear with the ECL intensity in the range of 3.0xl0(-6) to 3.0x10(-4)mol/L, and the detection limit (S/N=3) for BTPPO was 1.0x10(-7)mol/L. The possible mechanism for ECL of BTPPO at the GCE in the presence of hydrogen peroxide was also discussed. Furthermore, based on the fact that glucose oxidase can react with glucose to produce hydrogen peroxide, a new ECL sensing system of BTPPO has been developed for detection of glucose. The enhanced ECL intensity has a linear relationship with the concentration of glucose in the range of 1.0xl0(-4) to 1.0x10(-3)mol/L, and the detection limit for glucose is found to be 5.0x10(-5)mol/L (S/N=3).