https://vital.seals.ac.za/vital/access/manager/Index ${session.getAttribute("locale")} 5 https://vital.seals.ac.za/vital/access/manager/Repository/vital:56776 Wed 21 Sep 2022 19:37:22 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:50038 Wed 20 Apr 2022 08:42:45 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3873 Wed 12 May 2021 23:26:47 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3743 Wed 12 May 2021 23:03:21 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3824 Wed 12 May 2021 22:53:35 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3742 Wed 12 May 2021 22:53:24 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3730 Wed 12 May 2021 20:50:58 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3749 Wed 12 May 2021 20:37:38 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:31475 Wed 12 May 2021 20:33:38 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3767 Wed 12 May 2021 20:32:08 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:37893 Wed 12 May 2021 20:10:00 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3746 Wed 12 May 2021 19:48:45 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3751 Wed 12 May 2021 19:31:21 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3823 Wed 12 May 2021 19:27:48 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3822 Wed 12 May 2021 19:21:50 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3832 Wed 12 May 2021 19:11:31 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:27450 Wed 12 May 2021 19:11:09 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:28591 Wed 12 May 2021 19:06:38 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:28594 Wed 12 May 2021 19:05:02 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3819 Wed 12 May 2021 19:04:45 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3759 Wed 12 May 2021 19:03:28 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:20776 Wed 12 May 2021 18:51:19 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3748 Wed 12 May 2021 18:34:59 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3827 Wed 12 May 2021 18:34:07 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3724 Wed 12 May 2021 18:33:50 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3731 Wed 12 May 2021 18:33:10 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:20632 Wed 12 May 2021 17:57:06 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3825 Wed 12 May 2021 17:52:09 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:28405 Wed 12 May 2021 17:20:09 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3754 Wed 12 May 2021 17:12:57 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:29930 Wed 12 May 2021 17:04:13 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3862 Wed 12 May 2021 16:47:29 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:25546 Wed 12 May 2021 16:45:48 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3856 Wed 12 May 2021 16:43:12 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3860 Wed 12 May 2021 16:38:12 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3756 trifluoperazine> perphenazine > rochlorperazine. In order to assess their photostability an HPLC method was developed and validated for linearity, accuracy and precision, selectivity, limit of detection and quantitation and ruggedness. Preliminary solution photostudies under controlled light conditions (UV, sunlight, fluorescent light) indicated that the rate of degradation followed first-order kinetics with perphenazine the most susceptible to.photodegradation under all light conditions studied. In vitro and in vivo metabolism yielding the 5-sulphoxide and its reported presence on decomposition of the phenothiazines25 led to the development of a synthetic procedure suitable for the sutphoxides of all four derivatives based on the method proposed by Owens et al. in order to provide standards for comparison in the photostudies⁷. Since ICH regulations require that impurities> 0.1 % are examined and identified⁷⁴ and semi-preparative isolation of photoproducts proved unsuccessful, LC-MS having been well documented for structural.elucidation⁷⁵ ⁷⁵ ⁷⁶ ⁷⁷ was used to characterize solution (UV, sunlight, fluorescent light) and preliminary solid (UV) photostudies. The chloroderivatives underwent dechlorination and sulphoxidation with subsequent photosubstitution in the case of prochlorperazine to yield the 2-hydroxy derivative and sulphoxidation of the dechloro-derivative of perphenazine. The sulphoxides of both trifluoperazine and fluphenazine were formed with further oxidation to the respective sulphones occurring. Preliminary solid state (UV) photostudies showed fluphenazine to be the least stable with 30.71 % degradation as opposed to 7.57% for prochlorperazine, 4.28% for perphenazine and 7.10% for trifluoperazine witn sulphoxidation observed to be. the major degradation pathway. Since in vitro metabolism of perazine derivatives is reported to occur via N-oxidation, N-demethylation, sulphoxidation and aromatic hydroxylation¹⁸ it does appear that there is some correlation between metabolic and photoproducts. However the fact that solution (UV) photostudies indicates trifluoperazine to be the most and perphenazine the least stable does not concur with the proposed order of pharmacological activity.]]> Wed 12 May 2021 16:36:16 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3866 Wed 12 May 2021 16:33:12 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3849 Wed 12 May 2021 16:29:13 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3755 Wed 12 May 2021 16:23:46 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3771 Wed 12 May 2021 16:05:49 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:34583 Wed 12 May 2021 15:54:57 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3761 Wed 12 May 2021 15:53:48 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:41964 Wed 12 May 2021 15:07:56 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:42940 Wed 12 May 2021 14:54:05 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:41011 Wed 12 May 2021 14:53:50 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:27444 Tue 13 Jun 2023 11:29:15 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3766 Thu 13 May 2021 15:43:37 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3857 Thu 13 May 2021 13:27:11 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3733 Thu 13 May 2021 12:37:24 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3769 Thu 13 May 2021 10:28:35 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3760 Thu 13 May 2021 09:28:18 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:26599 0.999 were obtained for each assessment of linearity and FTC, TNF and EFV are linear in the range 0.4-40 μg/ml, 0.6-60 μg/ml and 1.2-120 μg/ml. The equation of the best-fit least squares regression lines for FTC, TNF and EFV were y = 0.0191x+0.0007, y = 0.0163x+0.0116 and y = 0.01x+0.016, respectively. The method is accurate as the y-intercept was < 2% of the detector response for all ARV, and the method is precise in terms of intra- and inter-assay precision as all % RSD < 2%. The stability-indicating nature of the method was demonstrated under acidic, alkaline and oxidative stress in addition to UV exposure and elevated temperatures, and the individual chromatograms were overlaid using Empower® 3 Software to establish whether there was interference with the peaks of interest. The forced degradation studies demonstrated the selectivity of the method for the ARV compounds. The method was applied to assay and in vitro dissolution studies of commercially available tablets. The amount of each active ingredient released from Atripla® was determined and compared to the amount of each drug released from Aspen Efavirenz® and Truvada® (a combination of FTC and TNF). The percent FTC released from Atripla® and Truvada® was similar based on the acceptance criteria for immediate-release BCS class 1 compounds. Statistical analysis was undertaken to compare the dissolution profiles of FTC, TNF and EFV. The percent of these compounds released in these studies indicate that bioequivalence testing would be required to declare these products interchangeable. The validated RP-HPLC and in vitro dissolution test method are suitable for routine quality control testing of solid oral dosage forms containing EFV, FTC and TNF, and as the dissolution method can discriminate between different formulations of the same molecule, these tools can also be used for analysis during formulation development studies. The method is not suitable for the analysis of the ARV plasma due to lack of sensitivity and an inability to quantitate the compounds at the required concentration levels. The use of HPLC with mass spectroscopy for quantitation would enhance the sensitivity of the method and may eliminate the quantitation of the molecules in the presence of interference that was observed when using UV detection. Fixed dose combination tablets are convenient for patient therapy and it is likely that in the future more molecules will be formulated into such dosage forms. However formulations such as these can pose significant difficulties when developing and using analytical methods for the quantitation of all compounds in the dosage form at the same time, in particular when the compounds have vastly different physico-chemical properties that impact the quality of a separation and therefore the analysis. Therefore when embarking on the development of FDC product cognisance of the difficulties of developing single methods for the analyses is required and approaches to overcome these difficulties should be considered.]]> Thu 13 May 2021 08:54:37 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3845 Thu 13 May 2021 08:22:13 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3820 Thu 13 May 2021 08:21:27 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3818 Thu 13 May 2021 08:08:29 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3843 Thu 13 May 2021 07:24:56 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:28538 Thu 13 May 2021 07:11:33 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:27441 Thu 13 May 2021 07:08:53 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:25414 Thu 13 May 2021 07:02:56 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3821 Thu 13 May 2021 07:02:33 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3764 Thu 13 May 2021 06:45:58 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3752 Thu 13 May 2021 06:26:12 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3831 Thu 13 May 2021 06:06:33 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3740 Thu 13 May 2021 05:53:41 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3747 Thu 13 May 2021 05:42:57 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3768 Thu 13 May 2021 05:09:22 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3758 Thu 13 May 2021 05:08:04 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3816 Thu 13 May 2021 05:05:04 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3863 Thu 13 May 2021 04:54:19 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3739 Thu 13 May 2021 04:41:32 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3757 Thu 13 May 2021 04:39:06 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3869 Thu 13 May 2021 04:37:15 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3826 Thu 13 May 2021 04:06:50 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3870 Thu 13 May 2021 03:35:30 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3763 Thu 13 May 2021 02:51:09 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:26600 Thu 13 May 2021 02:49:04 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3750 Thu 13 May 2021 02:47:17 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3762 Thu 13 May 2021 02:10:24 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3829 Thu 13 May 2021 01:36:56 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3770 Thu 13 May 2021 01:25:12 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:20983 Thu 13 May 2021 01:13:37 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3745 Thu 13 May 2021 01:12:16 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:26601 5% w/v led to a reduction in DLC and EE and an increase in PS with minimal impact on the ZP. Stability studies conducted at 25°C/65% RH and 40°C/75% RH for up to 30 days following manufacture revealed that batch SLM 15 manufactured using 10% w/v Labrafil® M2130 CS, 5% w/v KTZ and a combination of 4% w/v Pluronic® F-68, 2% w/v Tween 80 and 1% w/v sodium cholate produced the most stable dosage form when stored at 25°C/65% RH for up to 30 days. However, storage at 40°C/75% RH resulted in instability of the formulation. An aqueous dispersion of KTZ-loaded SLM has been developed and assessed and may offer an alternative to extemporaneous preparations used for KTZ therapy in paediatric and immuno-compromised patients.]]> Thu 13 May 2021 01:07:54 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3765 Thu 13 May 2021 00:59:57 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3753 Thu 13 May 2021 00:58:14 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:28593 Thu 13 May 2021 00:58:01 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3858 Thu 13 May 2021 00:56:49 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3729 Thu 13 May 2021 00:33:01 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3744 Thu 13 May 2021 00:05:50 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:27491 Thu 13 Apr 2023 14:17:25 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:27487 Thu 13 Apr 2023 13:21:19 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:27482 Thu 13 Apr 2023 10:12:27 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:28430 Thu 09 Mar 2023 13:07:21 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:28428 Thu 09 Mar 2023 11:57:44 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3741 Thu 06 Jul 2023 19:30:07 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:71771 Sat 02 Mar 2024 08:09:23 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:47448 Mon 24 Apr 2023 12:10:59 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:27447 Fri 06 Aug 2021 10:31:06 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3726 Fri 06 Aug 2021 10:17:09 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:42109 80%. The formulation composition identified was subsequently used for the optimization of the manufacturing parameters viz. sonication time and amplitude, using a Central Composite Design (CCD) . The LC and EE, in vitro CLA release, cytotoxicity, osmolarity, pH, degree of crystallinity and lipid modification, elemental analysis and surface morphology of the optimized batch was investigated and mon itored to ensure that CLA - loaded NLC, of the desirable quality, had been produced. On the day of manufacture the mean PS and PDI of the optimized CLA - loaded NLC formulation adjusted to physiological osmolarity (250 – 450 mOsm/kg) was 461.9 ± 40.16 nm and 0. 523 ± 0.104, respectively. The ZP for the optimized NLC generated on the day of manufacture using HPLC grade water as the dispersion medium was - 20.5 ± 4.82 mV. The pH and osmolarity of the optimized CLA - loaded NLC formulation was 7.76 ± 0.01 and 316 ± iii 2 m Osm/Kg, respectively and the EE was 88.62 ± 0.23 %. The optimized NLC exhibited a decreased crystallinity in comparison to the bulk lipid materials. DSC, WAXS and FT - IR revealed that CLA was molecularly dispersed in the nanocarriers. The optimized CLA - load ed NLC exhibited muco - adhesive properties, when tested under stationary conditions using laser doppler anemometry (LDA). The optimized formulation also exhibited sustained release of CLA over 24 hours during in vitro release testing and CLA release was bes t described using the Baker - Lonsdale model . The cumulative % CLA released over 24 hours was 56.13 ± 0.23% and mass balance analysis revealed 41.38 ± 0.02% CLA had been retained in the NLC. In vitro cytotoxicity testing revealed that the optimized CLA - NLC w ere less cytotoxic to HeLa cells when compared to CLA alone and further confirmed that the lipids and excipients used in these studies were of GRAS status . Stability studies revealed that the EE reduced over 28 days by 14.42% and 5.14% when stored at 4 °C and 22 °C , respectively. In addition, the particle size increased from the nm to μm range for samples stored at 22 °C. The findings are a good starting point but require further optimization to ensure prolongation of stability. In addition , the technology requires additional developmental studies and a powder for reconstitution for use as a single - dose considered as single dose packaging may be a solution to the compromised formulation stability observed in these studies. The CLA - NLC produced in these stu dies exhibit sound product attributes which serve as a useful foundation for the novel delivery of antibiotics to the eye. The results suggest that the optimized NLC have the potential to enhance precorneal retention and increase ocular availability of CLA , which in turn may be useful to reduce the required dose and dosing frequency when administering CLA as a reconstituted solution to treat susceptible organisms that infect ocular tissues.]]> Fri 06 Aug 2021 09:14:42 SAST ]]>