OBJECTIVEA method for determined oxygen permeability (Dk) of finished soft contact lens.

METHODSOxygen permeability(Dk) of 10 group finished soft contact lens was determined by polarographic method, and the values were linearly calibrated using the measured and established Dk values of the specified reference materials.

RESULTSOnly one Dk value fell outside of the requirement of GB 11417.3-2012 tolerance for Dk (± 20%).

CONCLUSIONIt is great practicability when determined the oxygen permeability (Dk) of finished soft contact lens by polarographic method which were linearly calibrated using the measured and established Dk values of the specified equal thickness reference materials without the measured lens customized 4 different thickness.

Calibration ; Contact Lenses, Hydrophilic ; Oxygen ; metabolism ; Permeability ; Polarography

AIMTo develop a new method for the determination of clarithromycin.

METHODSThe catalytic wave of clarithromycin in the presence of K2S2O8 was used for improving the analytical sensitivity. The rapid determination of clarithromycin has been carried out by linear single sweep polarography.

RESULTSThe reduction wave of clarithromycin appeared at ca. -0.79 V (vs SCE) in 0.24 mol x L(-1) KH2PO4-Na2HPO4 (pH 6.81) supporting electrolyte, which was ascribed to the reduction of carbonyl group on C-9 position. In the presence of 0.01 mol x L(-1) K2S2O8, the reduction wave was catalyzed to produce a parallel catalytic wave. The peak current of the catalytic wave was ca. Twenty times higher than that of the corresponding reduction wave. Based on the catalytic wave, a new method for the determination of clarithromycin has been proposed. The peak current of the catalytic wave was rectilinear to clarithromycin concentration in the range of 4.0 x 10(-7)-5.0 x 10(-5) mol x L(-1). The detection limit was 2.0 x 10(-7) mol x L(-1).

CONCLUSIONThe proposed method could be used for the direct determination of clarithromycin in pharmaceuticals and urine without preliminary separation.

Anti-Bacterial Agents ; analysis ; chemistry ; Catalysis ; Clarithromycin ; analysis ; chemistry ; Hydrogen-Ion Concentration ; Polarography ; methods ; Potassium Compounds ; chemistry ; Sulfates ; chemistry

AIMTo establish a polarographic method of parallel catalytic hydrogen wave for determination of glimepiride.

METHODSThe catalytic wave of glimepiride in the presence of K2S2O8 was used to improve the analytical sensitivity. The rapid determination of glimepiride was done by linear single sweep polarography.

RESULTSThe catalytic hydrogen wave of glimepiride was measured at ca. -1.36 (vs SCE) in 0.09 mol x L(-1) Na2B4O7-KH2PO4 (pH 6.24 +/- 0.1) supporting electrolyte. When 1.0 x 10(-2) mol x L(-1) K2S2O8 was present, the current increased by 25 times, and the peak potentioal was unchanged, producing a more sensitive parallel catalytic hydrogen wave. The peak current of the parallel catalytic hydrogen wave was rectilinear to the glimepiride concentration in the range 1.0 x 10(-7) - 4.2 x 10(-5) mol x L(-1) (r = 0.9990, n = 9). The detection limit was 5.0 x 10(-8) mol x L(-1).

CONCLUSIONThe proposed method could be applied to the determination of glimepiride in pharmaceuticals without preliminary separation.

Catalysis ; Humans ; Hypoglycemic Agents ; analysis ; urine ; Male ; Polarography ; methods ; Potassium Compounds ; analysis ; Sulfates ; analysis ; Sulfonylurea Compounds ; analysis ; urine

AIMTo investigate the inclusion of coenzyme Q10 with beta-cyclodextrin (beta-CD).

METHODSThe inclusion of the electroactive guest molecule coenzyme Q10 with the host molecule beta-CD was studied by the polarography. The change of the reduction peak current of the inclusion complex with time and the change of the peak potential of the inclusion complex with beta-CD concentration were examined. In order to study the photostability, the change of the reduction peak current of both coenzyme Q10 and coenzyme Q10-beta-CD inclusion complex with time were also examined under light, separately.

RESULTSIn 0.1 mol x L(-1) HAc/NaAc (pH 4.7) buffer-ethanol/water (60:40) medium, coenzyme Q10 was included with p-CD to form an 1:1 inclusion complex. The formation constant Kf was 1.26 x 10(4) L x mol(-1) the apparent formation rate constant was 6.64 x 10(-2) min(-1). The photodegradation apparent rate constant of coenzyme Q10 as 7.77 x 10(-3) min(-1) and that of the coenzyme Q10-beta-CD inclusion complex was 3.38 x 10(-3) min(-1).

CONCLUSIONThe inclusion of coenzyme Q10 with beta-CD took place. The stability of coenzyme Q10 to lights was improved in a certain degree due to the formation of the inclusion complex.

Coenzymes ; chemistry ; Drug Compounding ; methods ; Light ; Oxidation-Reduction ; radiation effects ; Polarography ; methods ; Ubiquinone ; analogs & derivatives ; chemistry ; beta-Cyclodextrins ; chemistry

PURPOSE: Thallous-201 chloride produced at Korea Cancer Center Hospital(KCCH) is used in detecting cardiovascular disease and cancer. Thallium impurity can cause emesis, catharsis and nausea, so the presence of thallium and other metal impurities should be determined. According to USP and KP, their amounts must be less than 2 ppm in thallium and 5 ppm in total. In this study, the detection method of trace amounts of metal impurities in [201Tl]TlCl injection with polarography was optimized without environmental contamination. MATERALS AND METHODS: For the detection of metal impurities, Osteryoung Square Wave Stripping Voltammetry method was used in Bio-Analytical System (BAS) 50W polarograph. The voltammetry was composed of Dropping Mercury Electrode (DME) as a working electrode, Ag/AgCl as a reference electrode and Pt wire as a counter electrode. Square wave stripping method, which makes use of formation and deformation of amalgam, was adopted to determine the metal impurities, and pH 7 phosphate buffer was used as supporting electrolyte. RESULTS: T1, Cu and Pb in thallous-201 chloride solution were detected by scanning from 300 mV to -800 mV. Calibration curves were made by using TlNO3, CuSO4 and Pb(NO3)2 as standard solutions. Tl was confirmed at -450 mV peak potential and Cu at -50 mV. Less than 2 ppm of Tl and Cu was detected and Pb was not detected in KCCH-produced thallous-201 chloride injection. CONCLUSION: Detection limit of thallium and copper is approximately 50 ppb with this method. As a result of this experiment, thallium and other metal impurities in thallous-201 chloride injection, produced at Korea Cancer Center Hospital, are in the regulation of USP and KP. Polarograph could be applied for the determination of metal impurities in the quality control of radiopharmaceuticals conveniently without environmental contamination.
Calibration ; Cardiovascular Diseases ; Catharsis ; Copper ; Electrodes ; Hydrogen-Ion Concentration ; Korea ; Limit of Detection ; Metals, Heavy* ; Nausea ; Polarography* ; Quality Control ; Radiopharmaceuticals ; Thallium ; Vomiting

AIMTo propose a new simple and sensitive voltammetric method for determination of proteins.

METHODSProtein with sulfhydryl or disulfide bond in 0.5 mol x L(-1) NaOH, 1.5 x 10(-4) mol x L(-1) Pb2+ and 0.02% tetrabutylammonium iodide was heated in boiling water for 5 minutes. The reactive product gave a well defined reductive adsorption wave at -0.66 V (vs SCE) by means of single sweep polarography, and the height of derivative wave was proportional to the concentration of proteins.

RESULTSThe peak height was linearly proportional to bovine serum albumin (BSA) or human serum albumin (HSA) concentration in range of 7.5 x 10(-10) -3.0 x 10(-7) mol x L(-1) (r(BSA) = 0.9995, and r(HSA) = 0.9990). The detection limit of BSA or HSA was 3.0 x 10(-10) mol x L(-1). For lysozyme (Lyso), the concentration range was from 1.4 x 10(-8) to 1.3 x 10(-6) mol x L(-10 (r(Lyso) = 0.9997) and the detection limit was 7.0 x 10(-9) mol x L(-1).

CONCLUSIONThe method is simple, rapid, sensitive and applicable to the assay of diluted human serum albumin samples.

Adsorption ; Animals ; Humans ; Lead ; Muramidase ; analysis ; Polarography ; methods ; Quaternary Ammonium Compounds ; Serum Albumin ; analysis ; chemistry ; Serum Albumin, Bovine ; analysis ; chemistry ; Sodium Hydroxide

AIMTo propose a polarographic method for the determination of irisquinone.

METHODSA reduction wave of irisquinone was recorded by single sweep oscillopolarography.

RESULTSIn 8.0 x 10(-3) mol.L-1 Na2B4O7-1.6 x 10(-2) mol.L-1 KH2PO4 (pH 7.7) supporting electrolyte, a redution wave of irisquinone with peak potential -1.23 V (vs SCE) achieved high sensitivity. The 2nd-order derivative peak current of the reduction wave was proportional to irisquinone concentration in the range of 1.5 x 10(-7)-5.2 x 10(-6) mol.L-1 (gamma = 0.9992, n = 9). The detection limit was 6.0 x 10(-8) mol.L-1. Relative standard deviation (RSD) was 0.87% by performing 13 independent measurements on 2.0 x 10(-6) mol.L-1 irisquinone.

CONCLUSIONThe proposed method was sensitive, simple, rapid, and can be applied to the determination of irisquinone in raw medicine and capsule.

Antineoplastic Agents, Phytogenic ; administration & dosage ; analysis ; chemistry ; Benzoquinones ; administration & dosage ; analysis ; chemistry ; isolation & purification ; Capsules ; Electrochemistry ; Iris ; chemistry ; Plants, Medicinal ; chemistry ; Polarography ; Seeds ; chemistry

In order to overcome the existing shortcomings of the non-invasive blood glucose polarized light measurement methods of optical heterodyne detection and direct detection, we present in this paper a new orthogonal twin-polarized light (OTPL) non-invasive blood glucose measurement method, which converts the micro-angle rotated by an optical active substance such as glucose to the energy difference of OTPL, amplifies the signals by the high-sensitivity lock-in amplifier made of relevant principle, controls Faraday coil current to compensate the changes in deflection angle caused by blood glucose, and makes use of the linear relationship between blood glucose concentration and Faraday coil current to calculate blood glucose concentration. In our comparative experiment using the data measured by LX-20 automatic biochemical analyzer as a standard, a 0.9777 correlation coefficient is obtained in glucose concentration experiment, and a 0.952 in serum experiment. The result shows that this method has higher detection sensitivity and accuracy and lays a foundation for the development of practical new type of non-invasive blood glucose tester for diabetic patients.
Animals ; Blood Glucose ; analysis ; Blood Glucose Self-Monitoring ; instrumentation ; methods ; Diabetes Mellitus ; blood ; Humans ; Optical Rotation ; Optics and Photonics ; Pilot Projects ; Polarography ; Rabbits

AIMTo propose a novel polarographic method for the determination of acetylspiramycin (ASPM) is proposed.

METHODSIn 0.1 mol x L(-1) NH4Cl-NH3 x H2O (pH 8.9) buffer containing dissolved oxygen, ASPM yielded a sensitive parallel catalytic hydrogen wave with the peak potential of -1.63 V (vs SCE) by single sweep polarography.

RESULTSThe 2nd order derivative peak currents (i(p)") of the parallel catalytic hydrogen waves of ASPM showed a linear relationship with its concentrations in the range from 1.74 x 10(-3) microg x mL(-1) to 3.84 microg x mL(-1) (r = 0.9979, n=13). Its detection limit was 5.80 x l0(-4) microg x mL(-1) (3sigma) and RSD (n=13) was 1.24% at the concentration level of 0.871 microg x mL(-1).

CONCLUSIONThe proposed method could be applied to the determination of ASPM in ASPM tablets.

Anti-Bacterial Agents ; administration & dosage ; analysis ; Catalysis ; Hydrogen ; Hydrogen-Ion Concentration ; Oxygen ; chemistry ; Polarography ; methods ; Reproducibility of Results ; Spiramycin ; administration & dosage ; analogs & derivatives ; analysis ; Tablets