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S Cai

Publications and source records attributed to S Cai.

At least 55 records · Page 3Linked to original sources

[Effect of hypertonic saline solution on the viscoelasticities of erythrocyte membrane in rats subjected to hemorrhagic shock].

We have studied the effect of hypertonic saline solution on the viscoelasticities of erythrocyte membrane in hemorrhage-shocked rats using micropippette aspiration technique. Wistar rats were randomly divided into three groups of 0.9% NaCl(NS), 7.5% NaCl (HS) and 5% NaCl-3.5% NaAc (HSA), respectively. The animals were bled to reach a mean arterial pressure of 5.3 kPa in 10 minutes and maintained in shock for 90 minutes. 4 ml/kg NS, HS and HSA was given intravenously and respectively in 5 minutes following hemorrhagic shock. The blood was collected to determine the viscoelasticities of erythrocyte membrane at baseline, shock and after treatment. The results showed that the elastic moduli and viscous coefficients of erythrocyte membrane were increased obviously following hemorrhagic shock. HS raised elastic moduli and reduced viscous coefficients significantly compared with NS after treatment. The elastic moduli and viscous coefficients of erythrocyte membrane were decreased remarkably in HSA group than in NS and HS group. These data suggested that HSA could improve the viscoelasticities of erythrocyte membrane significantly in rats subjected to hemorrhagic shock.

Animals↗

[Alveolar macrophage and airway inflammation in patients with chronic obstructive pulmonary disease].

OBJECTIVE: To investigate the effects of alveolar macrophage(AM) on airway inflammation of chronic obstructive pulmonary disease(COPD). METHODS: Broncho alveolar fluid(BALF) and bronchial mucosa biopsies were performed as usual. The levels of macrophage inflammatory-1 alpha (MIP-1 alpha), gelatinase B (MMP-9), interleukin(IL)-8 in BALF and the culture supernatants of AMs were measured with ELISA. The levels of endothelin (ET) were measured with radioimmunoassay method. The AMs expressing lymphocytic functional associated antigen-1 (LFA-1) in BALF, the AMs in mucosa and the thickness of mucosa were measured with immunocytochemistry and immunohistochemistry technique. RESULTS: The levels of MIP-1 alpha, MMP-9, IL-8 and ET in the culture supernatants of AMs in patients with COPD were (1 446.9 +/- 126.7) microg/L, (16.98 +/- 5.15) microg /L, (43.98 +/- 5.54) ng/L, (168.10 +/- 21.22) microg/L respectively; while those were (1 123.5 +/- 90.6) microg/L, (5.24 +/- 0.93) microg/L, (25.99 +/- 6.05) ng/L, (124.68 +/- 9.96) microg/L in a control group. The number of macrophages in mucosa in patients with COPD was (1.71 +/- 0.48) cells/Hp, while that was (0.59 +/- 0.18) cells/Hp in the control group (0.63 +/- 0.25) x 10(4). Statistical significance was found between the two groups. The number of AMs and polymorphonuclear leucocyte in BALF were inversely correlated with forced expiratory volume in one second as percentage of predicted value(FEV(1)% Pre) (r = -0.511, P < 0.01; r = -0.562, P < 0.01). The levels of MMP-9 and ET in the culture supernatants of AMs were inversely correlated with FEV(1)% Pre(r = -0.678, P < 0.01; r = -0.871, P < 0.01). Both the level of MIP-1 alpha and the positive number of AM expressing LFA-1 in BALF were positively correlated with the number of AMs in BALF(r = 0.572, P < 0.01; r = 0.625, P < 0.01). CONCLUSION: AM may be involved in the process of airway inflammation and subsequent airway obstruction.

Adult↗

[A study of hepatitis B virus(HBV) anti-genome and its inhibitory effect on HBV replication].

OBJECTIVE: To study the combination of triplex forming oligodeoxynucleotides (TFO) with hepatitis B virus gene and its effect on replication of HBV. METHODS: An oligodeoxynucleotide (TFO20) which can form triplex with SP1 sites in HBV core promoter was synthesized and was linked with biotin. Both the liposome-TFO20 and naked TFO20 were transfected to HepG2.2.15 cells, which was detected by SABC assay and showed signals that TFO20 was combined with HBV DNA. ELISA, reverse transcript (RT)-PCR and fluorescence quantitative PCR were used to investigate the change of HBV DNA, 3.5 kb/3.4 kb RNA, 2.4 kb/2.1 kb RNA, HBsAg and HBeAg in HepG2.2.15 cells before and after treatment with TFO20. RESULTS: The ratio of liposome-TFO20 and naked TFO20 transfected to HepG2.2.15 cells were 80% and 40%, respectively. TFO20 signals mainly distributed in the nucleus and cytoplasm. After treatment with TFO20, the level of HBV DNA was reduced from 10(7.01) to 10(4.94), while 3.5 kb/3.4 kb RNA, 2.4 kb/2.1 kb RNA, HBsAg and HBeAg were also reduced by 70.2%, 31.6%, 37.0%, 78.2% respectively. CONCLUSIONS: TFO20 can be transfected into cells by packing with liposome and can be combined with HBV DNA. TFO20 can effectively inhibit replication of HBV.

DNA Viruses↗

[The effect of Paeonol on erythrocyte deformability determined by micropipette aspiration technique].

OBJECTIVE: The effect of Paeonol (PAE) on erythorcyet(RBC) deformability was studied in order to provide experimental data for the application in clinic and the evaluation in pharmacological action. METHODS: Micropipette Aspiration Technique was used to determine the RBC deformation length. The method of calculation was also simplified and a new apparent deformation Index(ADI) was defined. RESULTS: PAE could increase the ADImin and ADImax and decrease Tmax significantly. CONCLUSION: PAE has the effect of deformational ability on RBC. Micropipette aspiration technique is a feasible method for determining the effect of traditional Chinese medicine on erythrocyte deformability.

Acetophenones↗

[Correlation of endotracheal tube biofilm and recurrent ventilator-associated pneumonia with Pseudomonas aeruginosa].

OBJECTIVE: To determine the correlation of endotracheal tube biofilm (ETT-BF) and recurrent ventilator-associated pneumonia with Pseudomonas aeruginosa (PA-VAP) in long-term ventilation patients. METHODS: Pulsed-field gel electrophoresis (PFGE) of Spe I enzyme-restricted chromosomal DNA was performed to identify the DNA patterns of Pseudomonas aeruginosa from ETT-BF, pharynx and lower respiratory tract secretion in 15 VAP patients. The chromosomal DNA fingerprint profile of each strain was compared with those from all other strains to calculate the similarity by using the correlation coefficient. The strains were then grouped and groups were depicted as a dendrite using the average clustering algorithm. RESULTS: When bacteria has been isolated from ETT-BF, the same DNA pattern species are isolated from the lower respiratory tract secretion in 7 of 15 patients. Recurrent PA-VAP is caused by closely related and indistinguishable isolates in 6 of 15 patients. All PEGE patterns from 9 patients are different from one another (correlation coefficient < 31.2%). CONCLUSIONS: The close pathogenic relationship between ETT-BF and lower airway secretion suggests that adhesive colonization of ETTs may be an important factor in the pathogenesis of VAP.

Aged↗

[The change of concentration of endothelin derived from alveolar macrophages and in induced sputum in patients with chronic bronchitis].

OBJECTIVE: To evaluate the changes of levels of endothelin (ET) in induced sputum, the culture supernatants of alveolar macrophages (AMs) and the culture supernatants of alveolar macrophages (AMs) when cultivated with aminophylline and lipopolysaccharide (LPS) in patients with chronic bronchitis and COPD. Then to investigate the role of ET derived from AMs in chronic bronchitis and COPD. METHODS: Fourteen patients with chronic bronchitis and thirteen patients with COPD were studied. Fourteen healthy were enrolled as control. Bronchoscopy and bronchial alveolar lavage were performed routinely, BAL cells were count with hemacytometer and differentater with wright stain. Sputum induction with 4% saline was performed on twenty-six subjects. The levels of ET in BALF and in the culture supernatants of AMs were measured by radioimmunoassay methods. RESULTS: (1) The number of all cells, neutrophils and AMs in BALF of patients with chronic bronchitis and COPD were significantly higher than those of healthy control group (P < 0.01 respectively). (2) The levels of ET in the culture supernatants of AMs and induced sputum were higher in heathy than those in patients with chronic bronchitis and COPD (P < 0.01 respectively). But there were no differences between patients with chronic bronchitis and COPD (P > 0.05 respectively). (3) Positive correlation was found between the levels of ET in the culture supernatants of AMs and those in induced sputum (r = 0.741, P < 0.01), between the number of AMs and the levels of ET in induced sputum (r = 0.597, P < 0.01). (4) Negative correlation was found between FEV(1)% of predicted value and the levels of ET in the culture supernatants of AMs in patients with COPD (r = -0.828, P < 0.01), between FEV(1)% of predited value and the levels of ET in induced sputum in patients with COPD (r = -0.748, P < 0.05). (5) In the culture with aminophylline, the level of ET derived from AMs remained stable (P > 0.05). But in the culture with LPS, the level of ET was significantly higher than that in the culture with DMEM (P < 0.01). CONCLUSIONS: (1) The characteristics of non-specific airway inflammation in patients with chronic bronchitis and COPD is the increased numbers of neutrophils and AMs. (2) AMs are perhaps important sources of ET in the lung. LPS can stimulate AMs to secrete more ET. ET derived from AMs takes part in development of COPD.

Adult↗

[Airway inflammation and macrophage inflammatory protein-1alpha, gelatinase B level in patients with COPD].

OBJECTIVE: To investigate the levels of macrophage inflammatory protein-1alpha (MIP-1alpha) and gelatinase-B (MMP-9) in bronchial alveolar lavage fluids (BALF) and supernatants of the cultured alveolar macrophages (AM) in patients with chronic bronchitis (CB) and chronic obstructive pulmonary disease (COPD). METHODS: Bronchial alveolar lavage (BAL) was performed bronchoscopically in CB group, COPD group, and control group. Total cells were counted using hemacytometer. Differential cell counts were made with Wright's stained cell smear. The levels of MIP-1alpha, MMP-9 in BALF and in supernatants of cultured AMs were measured by ELISA. RESULTS: The numbers of AMs and neutrophils in BALF in patients with CB and COPD groups were significantly higher than those in control group (P < 0.05). The levels of MIP-1alpha and MMP-9 in BALF and the supernatants of cultured AMs in patients with CB and COPD groups were higher than those in control group (P < 0.05). The levels of MIP-1alpha and MMP-9 in BALF were positively correlated with those in the supernatants of cultured AMs (r = 0.253, P < 0.05; r = 0.529, P < 0.01). The number of AMs in BALF was positively correlated with the level of MIP-1alpha and MMP-9 in BALF (r = 0.558, P < 0.01; r = 0.405, P < 0.01). Both AMs counts and the levels of MIP-1alpha, MMP-9 in BALF were inversely correlated with FEV(1.0)%pred (r = -0.322, P < 0.05; r = -0.319, P < 0.05; r = -0.616, P < 0.01). The levels of MIP-1alpha and MMP-9 in supernatants of the culture AMs were increased significantly after LPS stimulation (P < 0.05). CONCLUSION: AMs, which may be the most important cellular source of MIP-1alpha and MMP-9 in COPD, accelerate MIP-1alpha and MMP-9 accumulation in the lung, which exaggerates inflammation process in the airway.

Adult↗

[K. pneumoniea endotoxin induced mice beta-defensin-4 mRNA expression and its signaling transduction].

OBJECTIVE: To investigate the in vivo effects of Klebsiella pneumoniae endotoxin(LPS) on beta-defensin expression and the relevant signaling transduction pathway. METHODS: A LPS tolerant mouse C3H/HeJ with a point mutation at Toll-like receptor-4 (TLR4) gene and its wild type strain C3H/HeN were used in this study. C3H/HeJ and C3H/HeN were injected with 4 mg/kg of LPS intraperitoneally. The tracheas, lungs and kidneys of the C3H/HeJ and C3H/HeN were collected respectively at different LPS-treated time points, and the total RNA of each sample was extracted. The expression of mice beta-defensin-3 and/or beta-defensin-4 mRNA in these tissues was determined by reverse transcriptase-polymerase chain reaction (RT-PCR). The sequence of cDNA amplified from the lung of C3H/HeN treated by LPS for 24 h was analyzed. By using western blot, p-I kappa B alpha (phosphorylated I kappa B alpha) and I kappa B alpha of in the lungs of C3H/HeJ and C3H/HeN were detected at different time points after treatment with LPS or without LPS. RESULTS: 1. beta-defensin-4 mRNA was detected in the lungs of C3H/HeN after 24 h treatment with LPS. In contrast, no signal was determined in C3H/HeJ mice with LPS treatment and the C3H/HeN mice without LPS treatment. 2. Compared with the control, increas of the p-I kappa B alpha was observed in the lungs of C3H/HeN at 4 h after treatment with LPS, while both the p-I kappa B alpha and I kappa B alpha contents showed a tendency to go down at 8 h after treatment and dramatically decreased at 24 h. But there were no changes in the of p-I kappa B alpha and I kappa B alpha content the lungs of C3H/HeJ under the same conditions. CONCLUSION: K. pneumoniea endotoxin could induce the expression of beta-defensin-4 mRNA in the lung of C3H/HeN, and TLR4-mediated NF-kappa B activation signaling pathway may be responsible for this event.

Amino Acid Sequence↗

[Clinical study of the sentinel lymph node of patients with laryngeal and hypopharyngeal carcinomas].

OBJECTIVE: To investigate the methods of detecting the sentinel lymph node of laryngeal and hypopharyngeal carcinomas and its predictive value in the cervical metastasis of the carcinoma. METHODS: In 29 patients who suffered from laryngeal or hypopharyngeal carcinoma with NO neck, the patent blue was injected into the surrounding tissue of the tumor during the operation to identify the sentinel lymph nodes. The sentinel lymph nodes were dyed blue. The frozen histopathology was done during the operation, the lymph nodes at the ipsilateral side of the neck were dissected completely, and the routine histopathology was done as the gold standard to study the predictive value of the sentinel lymph node in the metastasis of the cervical node. RESULTS: Of 29 patients, 28 patients' sentinel lymph nodes were detected successfully during operation. There was an average of 2.5 lymph nodes per side per patient. Most of the sentinel lymph nodes were in the level II and level III regions of the ipsilateral side of the neck, and there were bilateral sentinel nodes in patients suffered from superglottic carcinoma. Three patients' sentinel lymph nodes were found to be positive in the frozen inspection, and the routine histopathology confirmed the result. The micrometastasis rate was 10.7% (3/28). There were no metastatic lymph nodes found in patients who were negative for the sentinel lymph nodes during the operative frozen histopathology. The predicted value of the sentinel lymph nodes to the cervical lymph node metastasis was 100 per cent. CONCLUSION: There is a very important predicted value of sentinel lymph nodes in the cervical metastasis of patients suffered from laryngeal and hypopharyngeal carcinomas. It could reduce the neck dissection in patients with laryngeal and hypopharyngeal carcinomas.

Adult↗

Evaluation of the diagnostic criteria for the localization of acquired arteriovenous fistulas by color Doppler flow imaging.

OBJECTIVE: To evaluate the diagnostic criteria for the localization of acquired arteriovenous fistulas (AVFs) by color Doppler flow imaging (CDFI) based on the features of their hemodynamic changes. METHODS: The shape and hemodynamic changes of involved vessels which could be helpful to localize the sites of fistulas were studied according to the observation of 10 cases of acquired AVFs. RESULTS: The sites of the fistulas could be shown by two-dimensional ultrasonography and color flow imaging in 40% and 80% cases, respectively. In all cases, turbulent high-velocity flow was present at the sites of the fistulas, low resistant flow was present in the arteries proximal to the fistulas, and artery-like flow was detected in the veins. CONCLUSION: CDFI was accurate for the localization of acquired AVFs, which were mainly localized by their hemodynamic changes shown by pulse Doppler ultrasound.

Adolescent↗

[Determination of enantiomeric purity of (S)-(-)-alpha-phenylethylamine by NMR].

It was reported the determination of enantiomeric purities of (S)-(-)-alpha-phenylethylamine by 1H NMR, using (2R, 3R)-dibenzoyl-tartaric acid as chiral solvating agent. 1H NMR chemical shift non-equivalence of the methyl doublet of alpha-phenylethylamine was 0.08 ppm(base-line separation) in solvent CDCl3, when the concentration of the sample was 0.051 mol.L-1, the molar ratio between chiral solvating agent and the sample was 0.33. The enantiomeric purities could be determined by the peak areas of the methyl doublet of alpha-phenylethylamine. The relative standard deviation depended upon the enantiomeric purities of sample. With enantiomeric purities as high as 99.1% ee, the RSD was 0.3% (n = 4).

Magnetic Resonance Spectroscopy↗

[In situ IR study of the reaction behavior of clusters [VnCr3-n (mu 3-O) (mu-O2CCH3)6(THF)3]X[n = 0-3, X = Cl-, ClO4-, (VO5)0.5-] and [VnFe3-n(mu 3-O) (mu-O2CCH3)6(THF)3]X(n = 0-3, X = Cl-) in nitrogen atmosphere].

The reaction behavior of the title complexes have been investigated by means of in situ IR in nitrogen atmosphere. It has been found that they enabled the acetic acid to convert to acetone and methane in different temperatures. The results indicate that the sequence of the ketonization reaction activity for the clusters was [V3OAT] > [VFe2OAT], [V2CrOAT] > [Fe3OAT], [VCr2OAT] > [Cr3OAT] [OAT = (mu 3-O) (mu-O2CCH3)6 (THF)3], and the sequence of the methanation reaction activity for the clusters was [Cr3OAT] > [VCr2OAT], [V2CrOAT] > [V3OAT] > [VFe2OAT], [Fe2OAH]. The ketonization reaction activity of [Fe3OAT] were obviously lower than that of [Fe3OAH] [OAH = (mu 3-O) (mu-O2CCH3)6 (H2O)3] and the methanation reaction activity of [Cr3OAT] were also much lower than that of [Cr3OAH]. The difference between [Fe3OAH], [Cr3OAT] and [Fe3OAH], [Cr3OAH] mentioned above were discussed.

English Abstract↗

[In situ IR study of the reaction behavior of transition metal oxides-propionic acid system, Fe2Cr(mu 3-O) (mu-O2CC2H5)6(H2O)3Cl.xH2O and Cr3 (mu 3-O) (mu-O2CC2H5)6(H2O)3NO3.xH2O].

The reaction behavior of the title complexes have been investigated by means of in situ IR in nitrogen atmosphere. It has been found that they enabled the propionic acid to convert to acetaldehyde and pentanone in different temperature. The sequence of the ketonization reaction activity for metal oxides Fe3O4 > MnO2 > Cr2O3 > Co2O3 > Ni2O3 has analogy to that for metal clusters [Fe2MnOPH] > [Fe3OPH] > [Fe2CrOPH] > [Fe2CoOPH] > [Fe2NiOPH] > [Cr3OPH][OPH = (mu 3-O)(mu-O2CC2H5)6(H2O)3]. For the ketonization reactions, the reaction temperatures of transition-metal oxides were much higher than that of corresponding metal clusters [Fe2MOPH]. It has been verified that the active component of metal cluster [Fe2MOPH] is not the corresponding transition-metal oxides. The difference between Fe3O4 and Fe2O3 which catalyze the conversion of propionic acid to acetaldehyde and pentanone respectively were demonstrated.

English Abstract↗

[Impacts of chemotherapy on long-term survival of patients with advanced epithelial ovarian cancer].

OBJECTIVE: To investigate the role of first-line chemotherapy in the management of advanced epithelial ovarian cancer (AEOC) and the effects on long-term survival epithelial. METHODS: From January 1986 to December 1997, 348 cases of stage III and IV epithelial ovarian cancer treated at our institute were reviewed retrospectively, and the patients were divided into optimal and suboptimal groups according to the size of residual disease after primary cytoreduction. Survival was calculated by Kaplan-Meier method with difference in survival estimated by Log-rank test. Long-term survival (5 years) determining factors were identified by Logistic regression model. RESULTS: The median age was 55 years (range, 20-82 years). In the optimal group, there was a significant difference in survival between patients with and without intraperitoneal chemotherapy, with an estimated median survival of 46 months and 36 months respectively (chi2 = 7.39, P = 0.0065). In the suboptimal group, the estimated median survival was 22 months in patients with more than 6 cycles of chemotherapy, 11 months in those less than 6 cycles (chi2 = 4.31, P = 0.0380). Neoadjuvant chemotherapy, tumor grade were independent prognostic factors of survival in this group. Size of residual disease, intraperitoneal chemotherapy, and tumor grade were determinants of long-term survival of AEOC. CONCLUSIONS: Multi-courses ( > 6) of platinum-based intravenous chemotherapy prolonged the survival of patients with suboptimal cytoreduction. Intraperitoneal chemotherapy was one of the dominant long-term survival determinants, and mainly on those with size of residual disease less than 1 cm.

Adult↗

pH and external Ca(2+) regulation of a small conductance Cl(-) channel in kidney distal tubule.

A single channel characterization of the Cl(-) channels in distal nephron was undertaken using vesicles prepared from plasma membranes of isolated rabbit distal tubules. The presence in this vesicle preparation of ClC-K type Cl(-) channels was first established by immunodetection using an antibody raised against ClC-K isoforms. A ClC-K1 based functional characterization was next performed by investigating the pH and external Ca(2+) regulation of a small conductance Cl(-) channel which we identified previously by channel incorporation experiments. Acidification of the cis (external) solution from pH 7.4 to 6.5 led to a dose-dependent inhibition of the channel open probability P(O). Similarly, changing the trans pH from 7.4 to 6.8 resulted in a 4-fold decrease of the channel P(O) with no effect on the channel conductance. Channel activity also appeared to be regulated by cis (external) Ca(2+) concentration, with a dose-dependent increase in channel activity as a function of the cis Ca(2+) concentration. It is concluded on the basis of these results that the small conductance Cl(-) channel present in rabbit distal tubules is functionally equivalent to the ClC-K1 channel in the rat. In addition, the present work constitutes the first single channel evidence for a chloride channel regulated by external Ca(2+).

Animals↗

Corneal macrophage infiltrates following ocular herpes simplex virus type 1 challenge vary in BALB/c mice vaccinated with different vaccines.

Macrophage cell infiltrates in the cornea were examined following ocular herpes simplex virus type 1 (HSV-1) challenge of vaccinated BALB/c mice. Mice were vaccinated with individual HSV-1 glycoproteins, cocktails of different HSV-1 glycoproteins, or live avirulent HSV-1 (strain KOS). Cryostat sections of cornea were taken at different times after challenge and reacted with M1/70, F4/80, BM8, or MOMA-1 monoclonal antibodies. The pattern of macrophage responses in the cornea differed depending on the vaccine that was given prior to HSV-1 ocular challenge. No macrophage response was detected in mice vaccinated with the highly protective 5gPs consisting of the five glycoproteins gB, gC, gD, gE, and gI. In contrast, mock vaccinated mice and mice vaccinated with gK, which is known to exacerbate HSV-1 induced eye disease, had high sustained macrophage responses. Mice vaccinated with 7gPs (5gPs+gG and gH) had moderate levels of macrophages. It appeared that (1) the most effective vaccines induced no detectable infiltrating macrophages in the eyes, while the least efficacious vaccines had very high levels of infiltrating macrophages; (2) presence of CD11b(+) cells in the cornea appeared to correlate with enhanced blepharitis, but did not appear to affect corneal scarring; and (3) presence of F4/80(+) cells in the cornea tended to correlate with increased corneal scarring.

Animals↗

Effect of latrunculin-A on morphology and actin-associated adhesions of cultured human trabecular meshwork cells.

PURPOSE: Determine the effects of the actin cytoskeleton disrupting compound latrunculin-A (LAT-A) on morphology, cytoskeleton, and cellular adhesions of cultured human trabecular meshwork (HTM) cells. METHODS: HTM cells were cultured to high confluence with endothelial-like morphology and treated with LAT-A at different doses and duration. Topography of living cells was evaluated by videomicroscopy. Distribution and organization of the actin-based cytoskeleton, vinculin- and paxillin-containing focal contacts, and beta-catenin-rich intercellular adhesions were determined by immunofluorescence and digital microscopy. RESULTS: LAT-A induced pronounced but highly reversible rounding of HTM cells, intercellular separation, and disruption of actin filaments. beta-catenin-rich intercellular adherens junctions were particularly sensitive to LAT-A. Vinculin- and paxillin-containing focal contacts were only partially affected and appeared to be more resistant to the drug than the intercellular interactions. CONCLUSIONS: The increase in outflow facility in the living primate eye induced by LAT-A may be due to the disorganization and disruption of the actin cytoskeleton and its associated cellular adhesions in the trabecular meshwork.

Actins↗

[Rapid determination of the ozone in water].

A new potassium iodide--N, N-diethy1-1,4-phenylen-ediammonium sulfate (DPD) spectrophotometry method for the determination of the ozone in water was established. The method was based on the quantitative reaction between the ozone and potassium iodide in buffered solution(pH 3.35): O3 + 2I- + 2H+-->O2 + I2 + H2O. Iodine could react with DPD regent and produce pink color. Its absorption was determined at 510 nm with spectrophotometer. The range of direct determination was 0-1.00 mg/L. Beer's law was obeyed in this range. The detection limit was 0.01 mg/L. The relative standard deviations were from 1.2% to 2.7% (n = 10). The recoveries were from 98.6% to 106.6%. Water samples were determined with both this method and iodimetry. The results were comparable. The method was applied to the determination of the ozone in water sample with satisfactory results. It was practical and reliable.

Ozone↗