Capsule Assay Research Articles

Determination of Tetracycline in Capsule Dosage Form

Background: Tetracycline antibiotic is widely prescribed that encourages the finding of rapid and reliable protocol for the determination of tetracycline hydrochloride in hard gelatine capsules. Recently, the standard addition method is used commonly with the aid of a UV-visible (UV-vis) spectrophotometer for such purpose. In this work, the authors aim to quantify the percent assay of Apcycline-250 capsules utilizing the standard addition protocol. Methods: Twenty filled and emptied capsules were weighed and an equivalent amount of 50 mg of tetracycline hydrochloride was diluted, filtered, and an appropriate standard was spiked and prepared for assay. Results: The λmax was found to be 348 nm and the absorbance vs. concentration standard addition curve was plotted for tetracycline hydrochloride capsules. This curve shows good linearity (R2 = 0.9994). The limit of detection (LoD) and limit of quantification (LoQ) were observed as 0.007937 and 0.02646, respectively. While the percent assay was 103.2%. Conclusion: The authors conclude that the standard addition technique is a reliable method to conduct rapid, economical, and validated day-by-day analyses work of tetracycline hydrochloride hard gelatine capsules.

Spectrophotometric Estimation of Iron (III) in Iron Polysaccharide Complex Capsule Formulation and its Accelerated Stability

Iron plays a pivotal role in human physiology, while its deficiency may prove fatal in severe cases. Analytical methods for the quantitative determination of iron are thus very important. Herein, we report the estimation of iron in iron Polysaccharide complex (IPSC) using raw material and formulations, through a spectrophotometric analytical method. IPSC capsules were formulated and their stability was studied by developing a simple and validated analytical method. The process is based on the acid hydrolysis of IPSC and the development of chromogen by reacting ammonium thiocyanate with IPSC, maximum absorption at 474 nm was observed. Beerand#39;s Lambert law (linearity response) was found in the range of 10-20 μg/ml with excellent correlation coefficient of determination (R = 0.998). The quantification and detection limits were established to be 0.45 mcg/ml and 0.14 mcg/ml correspondingly. The recovery of IPSC analysis was 99.25 to 102.28 %. Percentage assay of IPSC capsules showed results around 102.34 %. The formulated IPSC capsule was stable under accelerated conditions for 6 months (% assay andgt; 91.69). The dissolution profile over 60 minutes showed a better dissolution (94%) compared with the internationally marketed IPSC capsule (92%).

Assay of tipranavir capsules by a simple stability-indicating LC–UV method and cytotoxicity study of degraded samples

Tipranavir (TPV) is a protease inhibitor (PI) specially recommended for treatment-experienced patients who are resistant to other PI drugs. It was approved by FDA in 2005, but, until now, it has not been included in any official compendia. The objective of this study is to develop and validate a simple LC–UV method to assay TPV capsules, and to study the cytotoxicity of TPV and degraded samples over the cell viability. The optimized conditions were C8 Phenomenex® column (Luna®, 150 mm × 4.6 mm, 5 µm); mobile phase composed by methanol, acetonitrile, and acidified water pH 3.5 (40:31:29); flow rate 1.0 mL min−1 and detection at 254 nm. The cytotoxic effects of non-degraded and degraded TPV samples were evaluated in 3T3 cells by means of MTT viability assay. The method was linear in the range of 10–100 µg mL−1 (r = 0.9999) and specific, even in the presence of degradation products and impurities. The method showed suitable accuracy (mean recovery 100.02%), precision (RSD < 1.10%), and a two-level full factorial design indicated the robustness of the method. The degraded samples exhibited cytotoxicity patterns similar to TPV under controlled conditions. The method developed is appropriate for quality control of TPV capsules and stability studies.

Deletion of arcD in Streptococcus pneumoniae D39 Impairs Its Capsule and Attenuates Virulence

The arginine deiminase system (ADS) is associated with arginine catabolism and plays a role in virulence of several pathogenic bacteria. In Streptococcus pneumoniae, the ADS genes exist as a locus consisting of arcABCDT. A recent genome-wide mutagenesis approach revealed that both arcD and arcT are potentially essential in a chinchilla otitis media (OM) model. In the present study, we generated ΔarcD, ΔarcT, and ΔarcDT mutants by homologous recombination and evaluated their infectivity. Our results showed that only arcD, and not arcT, of an OM isolate is required during chinchilla middle ear infection. Additionally, D39 ΔarcD exhibited enhanced nasopharyngeal colonization and was attenuated in both mouse pneumonia and bacteremia models. In vitro, D39 ΔarcD displayed enhanced adherence to A549 epithelial cells and increased phagocytosis by J774A.1 macrophages compared to those with the parental strain. This mutant also exhibited an impaired capsule, as detected using electron microscopy, immunofluorescence, and a capsule assay. We demonstrated that the capsule defect in the D39 ΔarcD mutant may not be associated with a deficiency in arginine but rather is likely caused by a loss of interaction between the capsule and the transmembrane protein ArcD.

頭蓋内腫瘍化学療法における抗腫瘍剤感受性試験としてのSubrenal Capsule Assay の基礎的実験ならびに臨床応用に関する研究

頭蓋内腫瘍化学療法における抗腫瘍剤感受性試験としてのSubrenal Capsule Assay の基礎的実験ならびに臨床応用に関する研究

5-fluorouracil and uft-sensitive gastric carcinoma has a high level of thymidylate synthase

The authors examined the relationship between the level of thymidylate synthase (TS) and the sensitivity to 5-fluorouracil (5-FU) and UFT, a combined oral preparation of 1-(2-tetrahydrofuryl)-5-fluorouracil (tegafur) and uracil in a molar ratio of 1:4. For the studies we used the subrenal capsule (SRC) assay and 15 human gastric cancer tissues. The TS levels were assayed by the ligand-binding technique, using [6-3H]FdUMP. The relative variation of tumor size (delta TuS/TuS0) was calculated to be as follows: delta TuS/TuS0 = [(TuS6 - TuS0)/TuS0] x 100 (%), where TuS6 was the tumor size on day 6 and TuS0 on day 0. The chemosensitivity was considered to be positive when delta TuS/TuS0 in the treated group decreased to below -10%. Decrease in tumor size was marked in case of exposure to UFT (-19.8 +/- 13.0%) (mean +/- standard deviation), compared with that to 5-FU (-9.0 +/- 7.2%), with a statistically significant difference (P less than 0.001). The TS level varied from 1.7 to 30.8 pmol/g gastric cancer tissue and the mean was 7.1 +/- 7.2 pmol/g tissue. A correlation was noted between the TS level and decrease in size of the tumor exposed to 5-FU (r = -0.671) or UFT (r = -0.758): gastric cancer tissue with higher level of TS is more sensitive to 5-FU and UFT than is that with a lower TS level. These findings show that the sensitivity to 5-FU and UFT of gastric cancer tissue is related to the TS level and that UFT shows promise for the treatment of patients with gastric cancer.

Chemosensitivity test for carcinoma of digestive organs

For the chemosensitivity for carcinoma of digestive organs, gastric, colorectal, and hepatic cancer tissues were examined using in vitro succinate dehydrogenase inhibition (SDI) test and in vivo subrenal capsule (SRC) assay. The chemosensitivity varied in the tissue. The origin of an organ tumor, histological differentiation, and difference of primary or metastatic lesions are critical for determining chemosensitivity. Biochemical analysis shows that antitumor drugs have an increased susceptibility in tissues with high activity of pyrimidine nucleotide synthesis.

Sensitivity test for 5-fluorouracil and its analogues, 1-(2-tetrahydrofuryl)-5-fluorouracil, uracil/1-(2-tetrahydrofuryl)-5-fluorouracil (4:1) and 1-hexylcarbamoyl-5-fluorouracil, using the subrenal capsule assay.

The chemosensitivity of 20 human neoplastic tissues including 13 gastric and 7 colorectal cancers was tested using 5-fluorouracil (5-FU) and its analogues: 1-(2-tetrahydrofuryl)-5-FU (FT), uracil/FT (UFT) and 1-hexylcarbamoyl-5-FU (HCFU), and the in vivo subrenal capsule (SRC) assay. The relative variation of tumor size (delta TS/TSo) was calculated as follows: delta TS/TS0 = (TS6-TS0/TS0) x 100%, where TS6 was the tumor size on day 6 and TS0 on day 0, and the chemosensitivity was considered to be sensitive when delta TS/TS0 in the treated group was decreased to below -10%. The mean tumor size was -10.9 +/- (SD) 10.9% for 5-FU, -12.3 +/- 17.1% for FT, -18.4 +/- 15.8% for UFT and -17.9 +/- 15.4% for HCFU. The decrease of tumor size was marked when exposed to UFT (p less than 0.01) or HCFU (p less than 0.02), compared with that to 5-FU. Positive correlations were noted between the tumor sizes of 5-FU and its analogues (5-FU vs. FT, r = 0.851; 5-FU vs. UFT, r = 0.746; 5-FU vs. HCFU, r = 0.685). In 9 tissues resistant to 5-FU, 2 (22%) were sensitive to FT, 4 (44%) to UFT, 5 (56%) to HCFU and 7 tissues (78%) to at least one of these analogues. These results suggest that the SRC assay is useful for predicting the effective drug among 5-FU and 5-FU analogues, for individual patients with cancer.

Subrenal capsule (SRC) assay as a chemotherapeutic tool

Subrenal capsule (SRC) assay as a chemotherapeutic tool

Kinetic Method of Tetracycline and Oxytetracycline Assay Using Spect-Rophotometric Measurements

Abstract A Kinetic method is based on the degradation rate of tetracycline (TC) or oxytetracycline (OTC) to their anhydro derivatives with subsequent spectrophotometric measurements. With optimized degradation rate parameters, calibration curves relating decrease in absorbance difference (of alkaline solution versus acid solution) as a funotion of concentration in a range of 0.8-4.0 mg% are linear with negligible interecept. The method is applicable for powder and capsule assays and gives results within the pharmacopoeial limits.

AC Polarographic Determination of Cloxacillin

Hydrolysis of cloxacillin at pH 4.0 yields an electroactive product which can be determined by polarography. Depending on the concentration of cloxacillin, one of 2 peaks was obtained: The potential ac peaks for a 4.36 mM cloxacillin solution were peak I, -0.23 V and peak II, -0.13 V. For analytical purposes, the first peak was used. A linear relationship was established for levels of cloxacillin between 2.2 X 10(-5) and 2.2 X 10(-3)M. Average recovery was 98.8% (SD 1.8), indicating satisfactory accuracy for the method. Individual capsule and composite assays as well as interference tests are described.

Polarographic determination of temazepam in soft gelatin capsule formulations.

Precise and accurate procedures have been developed for the polarographic determination of temazepam in soft gelatin capsules. The capsule contents can be determined either by direct-current or by differential-pulse polarography. In order to cover the possibility of temazepam having diffused into the capsule shell a whole capsule assay has been developed based on directcurrent polarography: the differential pulse signal is considerably suppressed by the gelatin present in the shell. For capsules that have undergone storage tests at high temperatures leading to denaturisation, an enzyme dissolution step is included. The procedures are not subject to interference from known degradation products, and can therefore be used for stability determinations.

Modification of Present Procedures for the Determination of Conjugated Estrogens (Equine) in Various Low-Dosage Forms

Abstract The presently used procedures for the colorimetric determination of conjugated estrogens (equine) have been modified for the assay of tablets, capsules, liquids, and creams of low declaration per dosage unit. Modifications in sample chromatographic column preparation and elution have provided a more efficient extraction of the steroids.