scholarly journals Determination of Sulfate in Natural and Residual Waters by Turbidimetric Flow-Injection Analysis

2001 ◽  
Vol 84 (1) ◽  
pp. 59-64 ◽  
Author(s):  
Inês P A Morais ◽  
António O S S Rangel ◽  
M Renata S Souto
Keyword(s):  
Detection Limit ◽  
Flow Injection ◽  
Reference Method ◽  
Previous Treatment ◽  
Barium Chloride ◽  
Sulfate Solution ◽  
Injection System ◽  
Residual Water ◽  
Relative Standard

Abstract A turbidimetric flow-injection system was developed for the determination of sulfate in natural and residual water samples, with no previous treatment, using spectrophotometric detection. The precipitating agent, 7.0% (w/v) barium chloride solution prepared in 0.10% (w/v) polyvinyl alcohol, was added by using the merging-zones approach. A 100 mg/L sulfate solution in 0.07M nitric acid was mixed with the sample before it entered the injection loop to improve the detection limit, provide in-line pH adjustment, and prevent the interference of some anionic species. The relative standard deviations of the results were between 1.4 and 3.0% and were in agreement with results obtained by the reference method. Samples within a linear concentration range of 10–120 mg SO42−/L can be analyzed at a rate of 40/h. The detection limit is 5 mg SO42−/L.

scholarly journals Spectrophotometric flow injection procedure to indirect determination of paracetamol in pharmaceutical formulations using o-tolidine as reagent

2018 ◽  
Vol 33 (2) ◽  
pp. 47
Author(s):  
Orlando Fatibello-Filho ◽  
Heberth Juliano Vieira
Keyword(s):  
Standard Deviation ◽  
Detection Limit ◽  
Flow Injection ◽  
Pharmaceutical Formulations ◽  
Injection Method ◽  
Indirect Determination ◽  
Analytical Curve ◽  
Relative Standard ◽  
Injection Procedure

A spectrophotometric flow injection method for the determination of paracetamol in pharmaceutical formulations is proposed. The procedure was based on the oxidation of paracetamol by sodium hypochloride and the determination of the excess of this oxidant using o-tolidine dichloride as chromogenic reagent at 430 nm. The analytical curve was linear in the paracetamol concentration range from 8.50 x 10-6 to 2.51 x 10-4 mol L-1 with a detection limit of 5.0 x 10-6 mol L-1. The relative standard deviation was smaller than 1.2% for 1.20 x 10-4 mol L-1 paracetamol solution (n = 10). The results obtained for paracetamol in pharmaceutical formulations using the proposed flow injection method and those obtained using a USP Pharmacopoeia method are in agreement at the 95% confidence level.

scholarly journals Determination of Picogram Levels of Roxithromycin in Pharmaceutical, Human Serum, and Urine by Flow-Injection Chemiluminescence

2012 ◽  
Vol 2012 ◽  
pp. 1-5
Author(s):  
Jiangman Liu ◽  
Huan Yang ◽  
Yun Zhang ◽  
Min Wu ◽  
Haixiang Zhao ◽  
...  
Keyword(s):  
Human Serum ◽  
Flow Injection ◽  
Limit Of Detection ◽  
Inhibitory Effect ◽  
Injection System ◽  
Relative Standard ◽  
Flow Injection System ◽  
Flow Injection Chemiluminescence ◽  
Serum And Urine

A sensitive chemiluminescence (CL) method, based on the inhibitory effect of roxithromycin (ROX) on the CL reaction between luminol and dissolved oxygen in a flow-injection system, was first proposed for the determination of ROX at picogram levels. The decrement of CL intensity was linearly proportional to the logarithm of ROX concentrations ranging from 0.1 to 100 pg mL-1, giving the limit of detection (LOD) of 0.03 pg mL-1 (3σ). At a flow rate of 2.0 mL min-1, a complete analytical procedure including sampling and washing could be performed within 0.5 min, with relative standard deviations (RSDs) of less than 5.0% (n=5). The proposed procedure was applied successfully to the determination of ROX in pharmaceutical, human serum, and urine with the recoveries ranging from 90.0 to 110.0%.

scholarly journals DETERMINATION OF NITRAZEPAM IN PHARMACEUTICAL PREPARATIONS USING SOLID-PHASE REACTOR - REVERSE FLOW INJECTION ANALYSIS

2018 ◽  
Vol 11 (7) ◽  
pp. 487
Author(s):  
Mariam Jamal ◽  
Hind Hadi
Keyword(s):  
Flow Injection ◽  
Solid Phase ◽  
Reverse Flow ◽  
Injection System ◽  
Physical Parameters ◽  
Relative Standard ◽  
Solid Phase Reactor ◽  
Oxidation Reactor ◽  
Reverse Flow Injection

Objective: A simple and fast reverse flow injection system including a solid-phase reactor containing PbO2 with spectrophotometric detection was suggested for the determination of nitrazepam (NIT) in pharmaceutical tablets.Methods: The method was based on oxidation of the reagent (phloroglucinol) with PbO2 immobilized in a polymeric matrix which was then coupled with reduced NIT in aqueous medium. The pink-colored product was measured at 530 nm.Results: The calibration graph was linear over the range of 50–400 μg/mL with a relative standard deviation of <2% (n=29) and a sample throughput of 48 samples per hour. The variables of the solid-phase reactor such as composition, particle size, and length of the reactor were studied. The chemical and physical parameters, which affect the reverse flow method, were also studied.Conclusion: The oxidation reactor engaged with a flow system was successfully applied for the determination of NIT with good sensitivity and precision.

scholarly journals Spectrophotometric flow injection system for determination of Zn2+ in ophthalmic formulations using Alizarin red S

2018 ◽  
Vol 34 (2) ◽  
pp. 67
Author(s):  
Orlando Fatibello-Filho ◽  
Heberth Juliano Vieira
Keyword(s):  
Flow Injection ◽  
Sampling Rate ◽  
Alizarin Red S ◽  
Injection System ◽  
Borate Buffer Solution ◽  
Buffer Solution ◽  
Solution Ph ◽  
Alizarin Red ◽  
Relative Standard

A spectrophotometric flow injection method for the determination of Zn(II) in ophthalmic formulations was developed. In this work, Zn(II) ion was complexed with Alizarin red S in borate buffer solution (pH 9.0) and the chromophore produced was monitored at 520 nm. The analytical curve was linear in the Zn(II) concentration range from 6.05 x 10-6 to 1.50 x 10-4 mol L-1 with a detection limit of 3.60 x 10-6 mol L-1. Recoveries ranged from 96.3 to 105 % and a relative standard deviation of 1.2 % (n = 10) for 5.5x10-5 mol L-1 Zn(II) reference solution were obtained. The sampling rate was 60 h-1 and the results obtained of Zn(II) in ophthalmic products using this procedure are in close agreement with those obtained using a comparative spectrophotometric procedure at 95 % confidence level.

scholarly journals A simple flow-injection method for the determination of blood glucose using a Technicon immobilized enzyme coil

1989 ◽  
Vol 11 (2) ◽  
pp. 87-88 ◽  
Author(s):  
Sveinbjörn Gizurarson
Keyword(s):  
Blood Glucose ◽  
Detection Limit ◽  
Flow Injection ◽  
Immobilized Enzyme ◽  
Single Channel ◽  
Glucose Solution ◽  
Injection System ◽  
Flow Injection System ◽  
Simple Flow

The applicability of a single-channel flow-injection system with immobilized enzyme coil (Technicon) and UV detection to the determination of glucose is described. The method was used for a pure glucose solution and for serum. The detection limit was 0.10 mM, the rate of determination was 20-40 per hour and the precision was satisfactory. The system is very simple and practical when many analysis are to be determined periodically.

scholarly journals Merging Zones Standard Addition Technique for Determination of Copper in Beer by Flow Injection Atomic Absorption Spectrophotometry

1998 ◽  
Vol 81 (3) ◽  
pp. 645-647 ◽  
Author(s):  
Sílvia M V Fernandes ◽  
António O S S Rangel ◽  
José L F C Lima
Keyword(s):  
Atomic Absorption ◽  
Flow Injection ◽  
Sampling Rate ◽  
Reference Method ◽  
Atomic Absorption Spectrophotometry ◽  
Injection System ◽  
Absorption Spectrophotometry ◽  
Standard Additions ◽  
Determination Of Copper

abstract A flow injection system for determination of copper in beer by atomic absorption spectrophotometry by the standard additions method is described. The manifold, based on the merging zone technique, prevents the burner head from clogging, as observed with the conventional reference method. With 5 standard additions, results are comparable with those of the reference method. Relative deviations were less than 5.8%, precision was better than 6.4%, and sampling rate was about 30 samples/ h. A less precise, less accurate, but faster procedure (75 samples/h) is possible with only 2 standard additions. The detection limit was 5µg/l.

scholarly journals DETERMINATION OF ACETATE IN FOODS BY ION CHROMATOGRAPHY-FLOW INJECTION

1995 ◽  
Vol 3 (3) ◽  
pp. 9-22
Author(s):  
E. Esteve-Juan ◽  
R. Puchades ◽  
A. Maquieira
Keyword(s):  
Standard Deviation ◽  
Detection Limit ◽  
Ion Chromatography ◽  
Chromatographic Analysis ◽  
Reference Method ◽  
Spectrophotometric Detection ◽  
Flow Rates ◽  
Injection Volume ◽  
Relative Standard

A method for acetate determination using IC separation and FI post-column spectrophotometric detection based on the La(OH)3-I2 reaction has been developed. The chromatographic conditions (eluants, flow-rates, sensitivity, and so on) and FI variables (length of coils, injection volume, pH, ... ) were optimized. Linearity was observed over the concentration range 0 to 1 gl-1 with HAc as standard (r = 0.9916) and a detection limit of 0.1 g AcH/l. The IC-FI method afforded a low relative standard deviation (3.6%) and was free from interferences. The IC-FI procedure was applied to the determination of acetate in mustard sauce and the results obtained agree with those provided by the reference method. Additionally, the developed method permits the simultaneous chromatographic analysis of other anions such as chloride, nitrate, phosphate, sulphate, and so on.

scholarly journals Spectrophotometric flow injection procedure to indirect determination of paracetamol in pharmaceutical formulations using o-tolidine as reagent

2008 ◽  
Vol 33 (2) ◽  
pp. 47-54 ◽  
Author(s):  
O. Fatibello-Filho ◽  
H. J. Vieira
Keyword(s):  
Standard Deviation ◽  
Detection Limit ◽  
Flow Injection ◽  
Pharmaceutical Formulations ◽  
Injection Method ◽  
Indirect Determination ◽  
Analytical Curve ◽  
Relative Standard ◽  
Injection Procedure

A spectrophotometric flow injection method for the determination of paracetamol in pharmaceutical formulations is proposed. The procedure was based on the oxidation of paracetamol by sodium hypochloride and the determination of the excess of this oxidant using o-tolidine dichloride as chromogenic reagent at 430 nm. The analytical curve was linear in the paracetamol concentration range from 8.50 x 10-6 to 2.51 x 10-4 mol L-1 with a detection limit of 5.0 x 10-6 mol L-1. The relative standard deviation was smaller than 1.2% for 1.20 x 10-4 mol L-1 paracetamol solution (n = 10). The results obtained for paracetamol in pharmaceutical formulations using the proposed flow injection method and those obtained using a USP Pharmacopoeia method are in agreement at the 95% confidence level.

scholarly journals Ultrasensitive determination of amoxicillin using chemiluminescence with flow injection analysis

2006 ◽  
Vol 20 (1) ◽  
pp. 37-43 ◽  
Author(s):  
Xiaofeng Xie ◽  
Zhenghua Song
Keyword(s):  
Hydrogen Peroxide ◽  
Standard Deviation ◽  
Detection Limit ◽  
Flow Injection ◽  
Pharmaceutical Preparations ◽  
Chemiluminescence Intensity ◽  
Relative Standard ◽  
Human Urine And Serum ◽  
Urine And Serum

Results presented here reveal that amoxicillin can greatly enhance the chemiluminescence intensity generated from the reaction between luminol and hydrogen peroxide. The increment chemiluminescence signal was linearly dependent on amoxicillin concentration in the range from 10 pg·ml−1to 2 ng·ml−1(r2=0.9978) offering a detection limit as low as 3.5 pg·ml−1(3σ). At a flow rate of 2.0 ml·min−1, one analysis cycle, including sampling and washing, can be accomplished in 20 s with a relative standard deviation of less than 5%. The sensitive flow injection method was applied successfully to determine of amoxicillin in pharmaceutical preparations, human urine and serum without any pretreatment procedure, with recovery from 90.0% to 110.0% and relative standard deviations of less than 5.0%.

scholarly journals Determination of Manganese in Feedstuffs by Flow Injection Spectrophotometry Based on Rapid Formation of Permanganate at Room Temperature

2001 ◽  
Vol 84 (4) ◽  
pp. 1011-1016 ◽  
Author(s):  
Jing-Fu Liu ◽  
Ying-Di Feng ◽  
Gui-Bin Jiang
Keyword(s):  
Standard Deviation ◽  
Detection Limit ◽  
Flow Injection ◽  
Room Temperature ◽  
Sampling Rate ◽  
Relative Standard ◽  
Rapid Flow ◽  
Rapid Formation ◽  
Optimized Conditions

Abstract A simple and rapid flow injection spectrophotometric procedure was developed for determination of manganese. In the presence of pyrophosphate and acetate, manganese was immediately oxidized to permanganate by periodate at room temperature in slightly alkaline medium. Under optimized conditions, the determination was made with a sampling rate of 120/h, a linear range of 0–30 mg/L Mn(II), a detection limit (S/N = 3) of 0.08 mg/L, and a relative standard deviation of 0.6% (n = 11) at 10 mg/L Mn(II). The proposed method was used to determine manganese in trace mineral premixes and feedstuffs. Results agreed well with those obtained by the standard atomic absorption spectroscopy method.

Sign in / Sign up

Export Citation Format

Share Document