The correlation between the chemical stability and the microbiological activity of polymyxin B in phosphate buffer pH 6.0 and in proprietary eye drops was evaluated. High Performance Liquid Chromatography (HPLC) was used to quantify the amount of the main components in samples stored at 43,50,55 and 60°C for a period of 500 h. The data indicated that there are significant differences in chemical stability among the different proprietary eye drops. The accurate decomposition rate constants and shelf-lives (~o) at 4°C of two of the six formulated eye drops and the standard polymyxin B solution stored in glass containers at pH 6.0 were established. It was concluded that microbiological assay by agar diffusion was unsuitable for determining the activity of control polymyxin B in phosphate buffer and polymyxin B in eye drops. Killing time determinations for polymyxin B against cell suspensions of P. aeruginosa NCTC 6750 were consequently used. Thioglycollate broth containingp- aminobenzoic acid (PABA) 0.16 %w/v and magnesium sulphate 1 %w/v was used as an inactivating recovery medium. The effect of preservatives and of second antibacterials contained in the eye drops were tested individually and combined with polymyxin B. Thiomersal 0.001 %w/v, trimethoprim 0.02 %w/v and thiomersal 0.001 %w/v plus trimethoprim 0.02 %w/v did not have an effect on the activity of polymyxin B 2000 U/ml. Neomycin was an exception and at the concentrations in the range 0.0192 to 0.16 %w/v exhibited an antagonistic effect. Chemical interaction between polymyxin B and neomycin could not be detected and it was considered that the inhibitory effect of neomycin may be the result of competition between polymyxin B and neomycin for the same binding sites on the cell surface. Gentamicin is active against P. aeruginosa NCTC 6750 and at concentrations of 0.075 and 0.036 %w/v it exhibited an additive effect with polymyxin B 2000 U/ml against the test organism. The results obtained with the samples stored at 55°C for a period of 500 h demonstrated the critical effect of pH. At a pH of 6.0 microbiological activity and chemical stability appeared optimal. The chemical stability data of five eye drop samples correlated with microbiological activity data. Exceptions were polymyxin B in one eye drop sample and control polymyxin B. These extensively decomposed samples showed good antibacterial activity which appeared to result from the activity of decomposition products. Chemical stability data for standard polymyxin B solution at pH 6.0 also correlated to microbiological activity data over the temperature range of 92 - 115°C. The polymyxin B retained detectable microbiological activity when the amount of PB1 was greater than 20%. It is suggested that the decomposition products which occurred at these higher temperatures did not possess antibacterial activity.

Magister Pharmaceuticae - MPharm / Sutherlandia frutescens (tribe Galegeae, Fabaceae), is a popular medicinal plant traditionally used in South Africa. In 2000, a company called Phyto Nova (Pty) Ltd. initiated large-scale cultivation and contract manufacturing of tablets, made from the powdered herb (i.e. thin stems and leaves). Most of these commercial Sutherlandia solid dosage forms are made from the dried leaf powder but recently a new product, viz. Promune™ capsules, made from a freeze-dried aqueous extract, came on the market and was claimed to be “better” as it mimics the traditional tea. However, the pharmaceutical quality and stability of these preparations have not yet been investigated. The objectives of this study were firstly, to develop a validated stability-indicating HPLC assay for sutherlandioside B (SU-B); secondly, to compare the SU-B levels in the two commercially available Sutherlandia products viz, the Phyto Nova Sutherlandia SU1™ tablet and the Promune™ capsule, and, thirdly, to determine the effect of elevated temperature and humidity as well as acid hydrolysis on the SU-B levels in these two products. / South Africa

<p>Sutherlandia frutescens (tribe Galegeae, Fabaceae), is a popular medicinal plant traditionally used in South Africa. In 2000, a company called Phyto Nova (Pty) Ltd. initiated large-scale cultivation and contract manufacturing of tablets, made from the powdered herb (i.e. thin stems and leaves). Most of these commercial Sutherlandia solid dosage forms are made from the dried leaf powder but recently a new product, viz. Promune&trade / capsules, made from a freeze-dried aqueous extract, came on the market and was claimed to be &ldquo / better&rdquo / as it mimics the traditional tea. However, the pharmaceutical quality and stability of these preparations have not yet been investigated. The objectives of this study were firstly, to develop a validated stability-indicating HPLC assay for sutherlandioside B (SU-B) / secondly, to compare the SU-B levels in the two commercially available Sutherlandia products viz, the Phyto Nova Sutherlandia SU1&trade / tablet and the Promune&trade / capsule, and, thirdly, to determine the effect of elevated temperature and humidity as well as acid hydrolysis on the SU-B levels in these two products.</p>

<p>Sutherlandia frutescens (tribe Galegeae, Fabaceae), is a popular medicinal plant traditionally used in South Africa. In 2000, a company called Phyto Nova (Pty) Ltd. initiated large-scale cultivation and contract manufacturing of tablets, made from the powdered herb (i.e. thin stems and leaves). Most of these commercial Sutherlandia solid dosage forms are made from the dried leaf powder but recently a new product, viz. Promune&trade / capsules, made from a freeze-dried aqueous extract, came on the market and was claimed to be &ldquo / better&rdquo / as it mimics the traditional tea. However, the pharmaceutical quality and stability of these preparations have not yet been investigated. The objectives of this study were firstly, to develop a validated stability-indicating HPLC assay for sutherlandioside B (SU-B) / secondly, to compare the SU-B levels in the two commercially available Sutherlandia products viz, the Phyto Nova Sutherlandia SU1&trade / tablet and the Promune&trade / capsule, and, thirdly, to determine the effect of elevated temperature and humidity as well as acid hydrolysis on the SU-B levels in these two products.</p>

Glykerat hemoglobin, HbA1c, är en indikation på genomsnittligt glukosvärde. HbA1c används vid diagnostisering av diabetes men också uppföljning av diagnostiserade diabetiker. Uppföljningen visar hur väl diabetiker förhåller sig till kost men också medicinering. Informationen av patientens HbA1c värde spelar en stor roll i vidare behandlingar. Analysmetoden HbA1c är inte helt standardiserad vilket har medfört att flera analysmetoder utvecklats för HbA1c. Syftet med denna studie var att undersöka om en enzymatisk, Direct enzymatic HbA1c eller immunologisk analysmetod, Hemoglobin A1c kan lösa problemet med hemoglobin-variationer vid analys av HbA1c som idag analyseras med HPLC som rutin på klinisk kemi-laboratorium i Västerås. Genomförandet gjordes på två instrument, TOSOH G7 och AU 680. TOSOH:s värden (HPLC) användes vid jämförelse av de två analysmetoderna på AU680. Förberedelse och behandling, såsom hemolysering, skedde innan proven sattes i instrumentet AU680. Resultatet (n=134) visade att analysmetoden Hemoglobin A1c förhöll sig väl till HPLC analysmetod (R 2=0,98) jämfört med vad analysmetoden Direct enzymatic HbA1c gjorde (R2=0,86). Likartade resultat kunde observeras för Hemoglobin A1c (R2=0,98) och Direct enzymatic Hba1c (R2=0,95) då bara patientprov med hemoglobin-varianter analyserades (n=10). Mann-Whitney’s U-test vid analys av hemoglobin varianter med Hemoglobin A1c visade en tendens till signifikant skillnad gentemot HPLC analysen (p=0,051; n=34). Fel reagens erhölls från reagenstillverkaren gällande Direct enzymatic, Detta kan förklara det erhållna resultatet och kräver fler analyser med korrekta reagens. Hemoglobin A1c bör även undersökas vidare med mer omfattande provmaterial för möjlig standardisering i rutin hos KKTM i Västerås. / Glycated hemoglobin, HbA1c, is an indication of average long-term glucose. HbA1c is used as a diagnostic method for diabetes but also as a follow-up for diagnosed diabetics. Follow-ups shows how well a diabetic relates to diet but also medication. The information of the patient's HbA1c value plays an important factor in further treatments. The analysis method for HbA1c is not standardized, which has resulted in several analysis methods developed for HbA1c. The purposes of this study were to investigate whether an enzymatic, Direct enzymatic HbA1c or immunological assay method, Hemoglobin A1c, can solve the problem of hemoglobin variations in the analysis of HbA1c, which is currently analyzed by HPLC as a routine at the clinical chemistry laboratory in Västerås The implementation was performed on two instruments, TOSOH G7 and AU 680. The values from TOSOH (HPLC) were used for comparison of the two analysis methods applied on the AU680. Preparation and treatment, such as hemolysis, occurred before putting the samples into the AU680 instrument. The result showed that the Hemoglobin A1c assay method was well-matched with HPLC assay (R2 = 0.98) in comparison to that of the Direct enzymatic HbA1c assay method (R2 = 0.86). Similar results could be observed for Hemoglobin A1c (R2 = 0.98) and Direct Enzyme HbA1c (R2 = 0.95) when only samples from patients with hemoglobin variants were analyzed (n=10). Solely analysis of hemoglobin variants with Hemoglobin A1c showed a boundary case for a significant difference compared to HPLC analysis (P = 0.051; n=134). Incorrect reagents were obtained from the reagent manufacturer in the case of Direct enzymatic. This can explain the results obtained. Hemoglobin A1c should also be investigated with more extensive test materials for possible standardization in the routine of KKTM in Västerås.

Magister Pharmaceuticae - MPharm