Sequential Injection Analysis for Automation and Evaluation of Drug Liberation Profiles: Clotrimazole Liberation Monitoring

A fully automated sequential injection system was tested in terms of its application in liberation testing, and capabilities and limitations were discussed for clotrimazole liberation from three semisolid formulations. An evaluation based on kinetic profiles obtained in short and longer sampling intervals and steady-state flux values were applied as traditional methods. The obtained clotrimazole liberation profile was faster in the case of Delcore and slower for Clotrimazol AL and Canesten cream commercial formulations. The steady-state flux values for the tested formulations were 52 µg cm−2 h−1 for Canesten, 35 µg cm−2 h−1 for Clotrimazol AL, and 7.2 µg cm−2 h−1 for Delcore measured in 4 min sampling intervals. A simplified approach for the evaluation of the initial rate based on the gradient between the second and third sampling points was used for the first time and was found to correspond well with the results of the conventional methods. A comparison based on the ratio of the steady-state flux and the initial rate values for Canesten and Clotrimazol AL proved the similarity of the obtained results. The proposed alternative was successfully implemented for the comparison of short-term kinetic profiles. Consequently, a faster and simpler approach for dissolution/liberation testing can be used.

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Sequential Injection System for Analysis of Degree Brix, Orthophosphate and pH in Raw Sugarcane Juice Applicable to Sugar Industry

Molecules ◽

10.3390/molecules26216484 ◽

2021 ◽

Vol 26 (21) ◽

pp. 6484

Author(s):

Phoonthawee Saetear ◽

Nattinee Saechua ◽

Kamonthip Sereenonchai

Keyword(s):

Field Effect Transistors ◽

Sugar Industry ◽

Sugarcane Juice ◽

Injection System ◽

Sequential Injection Analysis ◽

Ph Sensing ◽

Sequential Injection ◽

Linear Calibration ◽

Molybdenum Blue ◽

Cane Juice

This work presents, for the first time, a new sequential injection analysis (SIA) method to simultaneously analyze degree Brix, orthophosphate and pH in raw cane juice. These key parameters relate to price of harvested sugarcane and quality of cane juice for sugar production. The SIA system employed two detectors: the first detector is a diode-array spectrophotometer, equipped with a regular flow cell, for measurements of degree Brix and orthophosphate. Quantitative of degree Brix (°Bx; ca. % (w/w) sucrose) was based on manipulation of the schlieren effect at the interface between plugs of sample and water. Orthophosphate analysis was carried out based on the molybdenum blue method with significant reduction in consumption of the reagents. Compensation of the schlieren effect from sucrose for determination of orthophosphate was achieved by using a dual-wavelength spectrometric detection. Second detector is a pH-sensing device, called ion-selective field-effect transistors (ISFET). The ISFET is based on the current through the ISFET arising according to the H+ concentration in solution. Our developed SIA system provides linear calibration graphs fitting for purpose in analysis of sugarcane juice (pH: 0–14, °Bx: 1.0–7.0 and P2O5: 20–200 mg L−1). Simultaneous analysis of sugarcane juice for pH, °Bx and P2O5 is carried out within 5 min (12 sample per h). Precision of SIA system is acceptable (RSD < 3%). Our SIA system gave quantitative results insignificantly different, as compared with conventional methods for analysis of pH, °Bx and P2O5 in sugarcane juice.

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Solid-phase reactors in sequential injection analysis. Determination of manganese(II) in tap water and effluent streams using a solid-phase lead(IV) dioxide reactor in a sequential injection system

Fresenius Journal of Analytical Chemistry ◽

10.1007/s002160000527 ◽

2001 ◽

Vol 370 (6) ◽

pp. 776-780 ◽

Cited By ~ 6

Author(s):

E. B. Naidoo ◽

J. F. van Staden

Keyword(s):

Solid Phase ◽

Tap Water ◽

Injection System ◽

Sequential Injection Analysis ◽

Sequential Injection ◽

Phase Lead ◽

Analysis Determination

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Development of an In Situ Analyzer Based on Sequential Injection Analysis and Liquid Waveguide Capillary Flow Cell for the Determination of Dissolved Reactive Phosphorus in Natural Waters

Sensors ◽

10.3390/s20102967 ◽

2020 ◽

Vol 20 (10) ◽

pp. 2967

Author(s):

Zeming Yang ◽

Cai Li ◽

Zhenzhao Zhang ◽

Guixin Lu ◽

Zifeng Cai ◽

...

Keyword(s):

Natural Waters ◽

Capillary Flow ◽

Northern South China Sea ◽

River Estuary ◽

Chemical Separation ◽

Flow Cell ◽

Injection System ◽

Sequential Injection Analysis ◽

Sequential Injection

This study presents an innovative technique for the in situ analysis of aquatic biochemical elements detected through wet chemical processes. A new compact in situ phosphate analyzer based on sequential injection analysis, liquid waveguide capillary flow cell and spectrophotometry was developed, and a safe and modular electronics-chemical separation mechanical structure was designed. The sequential injection system of this analyzer was optimized, and the major functions of this analyzer were studied and estimated. With a 10 cm liquid waveguide capillary flow cell and a 6.3 min time cost of detection, the analyzer reaches a detection limit of 1.4 μg·L−1 (≈14.7 nM, [PO43−]) and a consumption of 23 μL at most for each reagent. This analyzer was operated in situ and online during two scientific research cruises in the Pearl River Estuary and northern South China Sea. The advantages of this analyzer include its simple versatile manifold, full automation, low chemical consumption and electronics-chemical separate safe structure. Long-term in situ performance of this analyzer will be validated in the future.

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A Simplified Approach For Assessing Gravity-Viscous Effects In Horizontal Steady State Solvent Floods

10.2523/6823 ◽

1968 ◽

Author(s):

D. Pearson ◽

J. Bray ◽

N. Strom

Keyword(s):

Steady State ◽

Viscous Effects ◽

Simplified Approach

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Validation of On-line Respiration Meter and its Applications by Computer Simulation

Water Science & Technology ◽

10.2166/wst.1992.0578 ◽

1992 ◽

Vol 26 (5-6) ◽

pp. 1355-1363 ◽

Cited By ~ 2

Author(s):

C-W. Kim ◽

H. Spanjers ◽

A. Klapwijk

Keyword(s):

Steady State ◽

Activated Sludge ◽

Respiration Rate ◽

Oxygen Demand ◽

Operating Conditions ◽

Mass Balances ◽

Short Term ◽

Respiration Rates ◽

On Line ◽

Made In

An on-line respiration meter is presented to monitor three types of respiration rates of activated sludge and to calculate effluent and influent short term biochemical oxygen demand (BODst) in the continuous activated sludge process. This work is to verify if the calculated BODst is reliable and the assumptions made in the course of developing the proposed procedure were acceptable. A mathematical model and a dynamic simulation program are written for an activated sludge model plant along with the respiration meter based on mass balances of BODst and DO. The simulation results show that the three types of respiration rate reach steady state within 15 minutes under reasonable operating conditions. As long as the respiration rate reaches steady state the proposed procedure calculates the respiration rate that is equal to the simulated. Under constant and dynamic BODst loading, the proposed procedure is capable of calculating the effluent and influent BODst with reasonable accuracy.

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