scholarly journals Stability Studies of Twenty-Four Analytes in Human Plasma and Serum

2002 ◽  
Vol 48 (12) ◽  
pp. 2242-2247 ◽  
Author(s):  
Bobby L Boyanton ◽  
Kenneth E Blick

Abstract Background: The stability and stoichiometric changes of analytes in plasma and serum after prolonged contact with blood cells in uncentrifuged Vacutainer® tubes were studied. Methods: We simultaneously investigated the stability of 24 analytes (a) after prolonged contact of plasma and serum with blood cells and (b) after immediate separation of plasma and serum (centrifuged twice at 2000g for 5 min). We verified biochemical mechanisms of observed analyte change by concomitant measurement of pH, Pco2, and Po2. Hemolysis was qualitatively and semiquantitatively assessed. All specimens were maintained at room temperature (25 °C) and analyzed in duplicate 0.5, 4, 8, 16, 24, 32, 40, 48, and 56 h after collection. Statistically significant changes from the 0.5 h mean were determined using repeated-measures ANOVA. The significant change limit was applied to determine clinically significant changes in measured analytes. Results: Fifteen of 24 analytes in plasma and serum maintained in contact with cells showed clinically relevant changes, with the degree of change more pronounced in most plasma specimens. All analytes in plasma and serum immediately separated from cells after collection were stable. Conclusion: Storage of uncentrifuged specimens beyond 24 h caused significant changes in most analytes investigated because of (a) glucose depletion and Na+,K+-ATPase pump failure; (b) the movement of water into cells, causing hemoconcentration; and (c) leakage of intracellular constituents and metabolites. Immediate separation of plasma or serum from cells provides optimal analyte stability at room temperature. When prolonged contact of plasma or serum with cells is unavoidable, use of serum is recommended because of the higher instability of plasma analytes.

2017 ◽  
Vol 74 (19) ◽  
pp. 1579-1583 ◽  
Author(s):  
Abdel Naser Zaid ◽  
Rania Shtayah ◽  
Ayman Qadumi ◽  
Mashour Ghanem ◽  
Rawan Qedan ◽  
...  

Abstract Purpose The stability of an extemporaneously prepared rosuvastatin suspension stored over 30 days under various storage conditions was evaluated. Methods Rosuvastatin suspension was extemporaneously prepared using commercial rosuvastatin tablets as the source of active pharmaceutical ingredient. The organoleptic properties, dissolution profile, and stability of the formulation were investigated. For the stability studies, samples of the suspension were stored under 2 storage conditions, room temperature (25 °C and 60% relative humidity) and accelerated stability chambers (40 °C and 75% relative humidity). Viscosity, pH, organoleptic properties, and microbial contamination were evaluated according to the approved specifications. High-performance liquid chromatography was used for the analysis and quantification of rosuvastatin in selected samples. Microbiological investigations were also conducted. Results The prepared suspension showed acceptable organoleptic properties. It showed complete release of rosuvastatin within 15 minutes. The pH of the suspension was 9.8, which remained unchanged during the stability studies. The microbiological investigations demonstrated that the preparation was free of any microbial contamination. In addition, the suspension showed stability within at least the period of use of a 100-mL rosuvastatin bottle. Conclusion Extemporaneously prepared rosuvastatin 20-mg/mL suspension was stable for 30 days when stored at room temperature.


Author(s):  
Surbhi Rohilla ◽  
Dinesh Chandra Bhatt

In the present investigation an attempt was made to focus on the stability aspects of itraconazole hollow microsphere at refrigerated condition, room temperature and at accelerated condition. In stability studies, more emphasis given on the effect of different temperature conditions on appearance, % drug content, % buoyancy and % drug release of formulation over a period of 6 months. Apart from above studies, SEM and FTIR analysis was done to determine any change in morphology or chemical structure. The results showed non-significant changes in pharmaceutical properties. From result findings, it can be concluded that the itraconazole hollow microspheres are stable formulation to sustain the drug in upper GIT for prolonged period of time.


PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11207
Author(s):  
Pakkapon Rattanachaisit ◽  
Sirinporn Suksawatamnuay ◽  
Supachaya Sriphoosanaphan ◽  
Kessarin Thanapirom ◽  
Panarat Thaimai ◽  
...  

Background Hepatitis B virus (HBV) pregenomic RNA (pgRNA) has gained increasing attention owing to its role in replication of covalently closed circular DNA (cccDNA) in HBV. This marker has the potential to be used in clinical programs aimed to manage HBV infections. However, several reports on HBV pgRNA levels in clinical cases have conflicting results. RNA is easily degraded when exposed to heat and other environmental stressors. However, the stability of HBV pgRNA, during blood sample collection before the standard automated quantification, has never been estimated. This study aimed to demonstrate the effect of two different temperature conditions and storage durations on the stability of HBV pgRNA. Method Blood from forty patients with chronic hepatitis B infection, who also showed evidence of active HBV DNA replication, was collected and processed within 2 h of collection. Plasma from each patient was divided and stored at 4 °C and 25 °C (room temperature) for six different storage durations (0, 2, 6, 12, 24, and 48 h) and subsequently transferred to −80 °C for storage. The effect of multiple cycles of freezing and thawing of plasma at −20 °C or −80 °C was evaluated using samples from ten patients. Quantification of pgRNA from the samples was performed simultaneously, using the digital polymerase chain reaction (dPCR) method. The differences in pgRNA levels at baseline and each time point were compared using generalized estimating equation (GEE). A change greater than 0.5 log10 copies/mL of pgRNA is considered clinically significant. Statistical analyses were conducted using Stata 16.0. Results The mean HBV pgRNA level in the initially collected plasma samples was 5.58 log10copies/mL (ranging from 3.08 to 8.04 log10 copies/mL). The mean pgRNA levels in samples stored for different time periods compared with the initial reference sample (time 0) significantly decreased. The levels of pgRNA for 6, 12, 24, and 48 h of storage reduced by −0.05 log10 copies/mL (95% confidence interval (CI) −0.095 to −0.005, p = 0.03), −0.075 log10 copies/mL (95% CI [−0.12 to −0.03], p = 0.001), −0.084 log10 copies/mL (95% CI [−0.13 to −0.039], p =  < 0.001), and −0.120 log10 copies/mL (95% CI [−0.17 to −0.076], p =  < 0.001), respectively. However, these changes were below 0.5 log10 copies/mL and thus were not clinically significant. Compared with the samples stored at 4 °C, there were no significant differences in pgRNA levels in samples stored at 25 °C for any of the storage durations (−0.01 log10 copies/mL; 95% CI [−0.708 to 0.689], p = 0.98). No significant difference in the levels of pgRNA was observed in the plasma samples, following four freeze-thaw cycles at −20 °C and −80 °C. Conclusion The plasma HBV pgRNA level was stable at 4 °C and at room temperature for at least 48 h and under multiple freeze-thaw cycles. Our results suggest that pgRNA is stable during the process of blood collection, and therefore results of pgRNA quantification are reliable.


1994 ◽  
Vol 28 (6) ◽  
pp. 712-714 ◽  
Author(s):  
Daniel T. Casto

OBJECTIVE: To evaluate the stability of ondansetron hydrochloride undiluted and mixed in dextrose 5% injection or NaCl 0.9% injection during storage in polypropylene syringes when frozen, refrigerated, or at room temperature. DESIGN: Batch quantities of ondansetron 0.25, 0.5, 1.0, and 2.0 mg/mL were prepared and individual doses of 10.5 mg were drawn into polypropylene syringes that were stored at −20 °C for up to 3 months, at 4 °C for up to two weeks, or at 22–25 °C for two days, and various combinations of these conditions. At defined sampling times aliquots were withdrawn from syringes, the solution visually inspected, pH measured, and ondansetron concentration determined by HPLC. Drug loss of ≥10 percent of the original content of the solution was considered clinically significant. RESULTS: The ondansetron concentration in each solution, regardless of storage conditions, remained above 90 percent of the original concentration at each observation time (range 92–107 percent). No changes in color or clarity of any of the solutions were observed, and only slight fluctuations in pH (≤0.05) were noted. CONCLUSIONS: Ondansetron 2 mg/mL undiluted, or at concentrations of 0.25, 0.5, or 1 mg/mL, mixed in dextrose 5% injection or NaCl 0.9% injection was determined to be stable when stored in polypropylene syringes for each storage condition at all time points studied, including the maximum for each: three months at −20 °C, followed by 14 days at 4 °C, and by 48 hours at 22–25 °C.


2001 ◽  
Vol 47 (10) ◽  
pp. 1829-1835 ◽  
Author(s):  
Yoshiyuki Tanaka ◽  
Yuichiro Noda ◽  
Mayumi Kobayashi ◽  
Yasuko Yamada ◽  
Konomu Hirao

Abstract Background: Blood sampling by finger puncture is convenient, but the need for centrifugation and the problem of hemolysis remain, as does instability when samples must be shipped for analysis. We aimed to develop a blood-sampling device that provided high yields of serum with limited hemolysis and enabled preservation of serum components for at least 7 days at room temperature. Methods: For separation of blood cells, we devised a grooved, asymmetric, polysulfonate membrane impregnated with sucrose. We evaluated hemoglobin (Hb) concentrations in the serum, assay values for 15 frequently measured serum components (including glucose), and the stability of analytes in the device. Results: In sera from the new device, the Hb concentration was ≤0.43 mg/L. Recovered serum contained 65.0% ± 4.2% (mean ± SD; n = 41) of each of the serum components obtained by centrifugation. Serum components were stable in the device for 10 days at room temperature (25 °C). Conclusions: The newly developed device allows recovery of 60% of serum components from microvolumes of blood by finger puncture with neither degradation of analytes at room temperature nor hemolysis.


2020 ◽  
Vol 90 (5) ◽  
pp. 627-633
Author(s):  
Marcos J. Carruitero ◽  
Aron Aliaga-Del Castillo ◽  
Daniela Garib ◽  
Guilherme Janson

ABSTRACT Objectives To evaluate the stability of maxillary interincisor diastema closure and the relationship between space relapse and interincisor diastema width, overjet, overbite, angulations between adjacent maxillary anterior teeth and presence of intermaxillary osseous cleft after orthodontic treatment with extractions. Materials and Methods Twenty-four individuals with a maxillary interincisor diastema pretreatment, treated with maxillary first premolar extractions were evaluated. Dental casts and panoramic radiographs taken at pretreatment (T1), posttreatment (T2), and posttreatment follow-up (T3) were assessed. Periapical radiographs at T1 and T2 were also evaluated. Diastema relapse was assumed when T3-T2 interincisor space change was greater than zero. Diastema relapse was considered clinically significant when it was at least 0.50 mm. Data were analyzed using repeated-measures analysis of variance followed by post hoc Tukey tests or Friedman followed by Wilcoxon tests. T-test or Mann-Whitney U-test, Pearson correlation coefficient, and multiple linear regression analyses were also performed. Results No statistically significant relapse of maxillary interincisor diastemas was found. The percentage of clinically significant relapse of the maxillary interincisor diastemas was 27.78%. Specifically, for the interincisor midline diastema, it was 8.33%. Conclusions Maxillary interincisor diastema closure showed no statistically significant relapse after orthodontic treatment with premolar extractions. Clinically significant stability for maxillary interincisor diastema closure was 72.22% and, specifically, for interincisor midline diastema closure, it was 91.67%.


2016 ◽  
Vol 36 (4) ◽  
pp. 421-426 ◽  
Author(s):  
Dwarakanathan Ranganathan ◽  
Saiyuri Naicker ◽  
Steven C. Wallis ◽  
Jeffrey Lipman ◽  
Sharad K. Ratanjee ◽  
...  

Background and objectivesPatients with peritoneal dialysis (PD)-associated peritonitis may be advised to store PD-bags with pre-mixed antibiotics at home, although there is a paucity of antibiotic stability studies in the commonly used icodextrin solutions. The purpose of this study was to assess the stability of various antibiotics in PD-bags when stored at different temperatures over a 14-day period.Methods7.5% icodextrin PD-bags were dosed with gentamicin 20 mg/L ( n = 9), vancomycin 1,000 mg/L ( n = 9), cefazolin 500 mg/L ( n = 9) and ceftazidime 500 mg/L ( n = 9) as for intermittent dosing. Combinations of gentamicin/vancomycin ( n = 9), cefazolin/ceftazidime ( n = 9), and cefazolin/gentamicin ( n = 9) were also tested. Nine drug-free bags were used as controls. Bags were stored in triplicate at 37°C, room-temperature (25°C), and refrigeration (4°C). Antibiotic concentrations were quantified at various time intervals using validated chromatography. Storage duration was considered unstable if the concentration of the antibiotic dropped ≤ 90% of the initial value.ResultsGentamicin was stable for 14 days at all temperatures. Vancomycin was stable for 4 days at 37°C and for 14 days at both 25°C and 4°C. The gentamicin and vancomycin combination was stable for 4 days at 37°C and for 14 days at 25°C and 4°C. Cefazolin alone was stable for 24 hours at 37°C, 7 days at 25°C, and 14 days at 4°C. Ceftazidime alone was stable for only 6 hours at 37°C, 2 days at 25°C, and 14 days at 4°C. The cefazolin and ceftazidime combination was stable for 24 hours at 37°C, 2 days at 25°C, and 14 days at 4°C. The cefazolin and gentamicin combination was stable for 1 day at 37°C, 4 days at 25°C, and 14 days at 4°C.ConclusionsAntibiotics premixed in icodextrin PD-bags have varying stabilities with stability generally least at 37°C and best at 4oC, permitting storage for 14 days when refrigerated and pre-warming to body temperature prior to administration. Further research confirming the sterility of these antibiotic-containing bags is recommended.


1992 ◽  
Vol 26 (6) ◽  
pp. 768-771 ◽  
Author(s):  
C. Lynn Graham ◽  
George E. Dukes ◽  
Cheng-Fang Kao ◽  
Jeanne M. Bertch ◽  
Lawrence J. Hak

OBJECTIVE: To determine the stability of ondansetron hydrochloride in large-volume parenteral solutions under four storage and time-period conditions. DESIGN/METHOD: Ondansetron was added to each of the following commercially available solutions to make final concentrations of approximately 24 and 96 μg/mL: NaCl 0.9%, D5W, and lactated Ringer's solution. SETTING: University analytical laboratory. MAIN OUTCOME MEASURES: Each solution was studied at both concentrations under the following conditions: (1) 1 day refrigerated, 2 days room temperature; (2) 7 days refrigerated, 2 days room temperature; (3) 14 days refrigerated, 2 days room temperature; and (4) 14 days room temperature. All solutions were exposed to fluorescent light when under room temperature conditions and were studied in triplicate. Ondansetron concentrations of samples were obtained periodically throughout each storage/time condition via a specific, stability-indicating HPLC method. RESULTS: A clinically significant loss of concentration was defined as >10 percent decrease from the initial concentration. In all solutions and at both concentrations studied, the mean ondansetron concentration was ≥90 percent under all storage and time conditions. CONCLUSIONS: Ondansetron can be stored and administered in these solutions without loss of potency.


Author(s):  
Michael Worlako Klu ◽  
John Antwi Apenteng ◽  
Bright Selorm Addy ◽  
David Ntinagyei Mintah ◽  
Elikem Katsekpor

Objective: Stability studies on flucloxacillin sodium in reconstituted oral suspensions were carried out. The experiment sought to investigate the effects that the different types of water for reconstitution and different storage conditions have on the stability of flucloxacillin sodium in the reconstituted suspensions.Methods: Suspensions of flucloxacillin sodium were reconstituted with tap water, commercial bottled water (Voltic brand was used), commercial sachet water (Everpure brand was used) treated tap water and distilled water and stored under refrigeration (RF) (4-6 °C), at room temperature (RT) (31-33 °C) and in a bowl of water (BW) (26-27 °C). Assay of flucloxacillin sodium was by iodimetry at predetermined time intervals for 8 d.Results: The amount of flucloxacillin sodium in all the suspensions stored under the various storage conditions reduced with time and at different rates. The percentage breakdown, a parameter of stability, was calculated for each reconstituted suspension stored at the different conditions investigated and they were as follows: commercial bottled water (RT-22.40 %, RF-9.90 % and BW-15.90 %), distilled water (RT-29.14 %, RF-18.0 %, BW-28.80 %), tap water (RT-25.0%, RF-14.60 % and BW-25.10 %) and commercial sachet water (RT-25.0 %, RF-10.17 % and BW-22.50 %).Conclusion: At the end of the study, it was found that those suspensions reconstituted with the commercial bottled water were the most stable and had the smallest breakdown of flucloxacillin sodium whereas those reconstituted with distilled water were the least stable and had the largest breakdown of flucloxacillin sodium. Commercial sachet water reconstituted more stable suspensions than tap water. Also, the suspensions stored under refrigeration were the most stable followed by those stored in a bowl of water. The formulations kept at room temperature were the least stable and thus, had the largest breakdown of flucloxacillin sodium.


2008 ◽  
Vol 99 (02) ◽  
pp. 416-426 ◽  
Author(s):  
Manuel Zürcher ◽  
Irmela Sulzer ◽  
Gabriela Barizzi ◽  
Bernhard Lämmle ◽  
Lorenzo Alberio

SummaryMany preanalytical variables affect the results of coagulation assays. A possible way to control some of them would be to accept blood specimens shipped in the original collection tube. The aim of our study was to investigate the stability of coagulation assays in citrated whole blood transported at ambient temperature for up to two days after specimen collection. Blood samples from 59 patients who attended our haematology outpatient ward for thrombophilia screening were transported at ambient temperature (outdoor during the day, indoor overnight) for following periods of time: <1 hour, 4–6, 8–12, 24–28 and 48–52 hours prior to centrifugation and plasma-freezing. The following coagulation tests were performed: PT, aPTT, fibrinogen, FII:C, FV:C, FVII:C, FVIII:C, FIX:C, FX:C, FXI:C,VWF:RCo,VWF:Ag, AT, PC activity, total and free PS antigen, modified APC-sensitivity-ratio, thrombin-antithrombin-complex and D-dimer. Clinically significant changes, defined as a percentage change of more than 10% from the initial value, were observed for FV:C, FVIII:C and total PS antigen starting at 24–28 hours, and for PT, aPTT and FVII:C at 48–52 hours. No statistically significant differences were seen for fibrinogen, antithrombin, or thrombin-antithrombin complexes (Friedman repeated measures analysis of variance).The present data suggest that the use of whole blood samples transported at ambient temperature may be an acceptable means of delivering specimens for coagulation analysis. With the exception of factorV andVIII coagulant activity, and total PS antigen all investigated parameters can be measured 24–28 hours after specimen collection without observing clinically relevant changes.


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