Stability of varenicline concentration in saliva over twenty-one days at three storage temperatures

2021 ◽  
Author(s):  
Maria Novalen ◽  
Meghan J Chenoweth ◽  
Bin Zhao ◽  
Larry W Hawk, Jr. ◽  
Rachel F Tyndale
Keyword(s):  
Quality Control ◽  
Smoking Cessation ◽  
Room Temperature ◽  
Freezing And Thawing ◽  
Storage Duration ◽  
Non Invasive ◽  
Specimen Collection ◽  
Repeated Freezing ◽  
The Stability ◽  
Storage Temperatures

Abstract Introduction Varenicline is the most efficacious drug for smoking cessation; saliva varenicline concentrations can be useful for the evaluation of adherence in smoking cessation trials. Saliva is a useful non-invasive matrix for mail-in specimen collection, if stable. We investigated the stability of varenicline in saliva at different storage temperatures simulating the time it takes to mail in a sample. Methods We evaluated the concentrations of varenicline, nicotine, cotinine, 3’-hydroxycotinine and 3’-hydroxycotinine/cotinine (3HC/COT) ratio in quality control saliva samples (and after repeated freezing and thawing), and in smokers’ saliva samples, stored for up to 21 days at room temperature (~25°C), 4°C and -80°C. Results In saliva quality control samples, concentrations of varenicline, nicotine, cotinine, 3’-hydroxycotinine and 3HC/COT remained unchanged and showed little within-sample variation (CV≤5.5%) for up to 21 days at the three storage temperatures; they were also not altered after three thaw-freeze cycles. In smokers’ saliva, a significant main effect of storage duration, but not temperature, was observed for varenicline, cotinine and 3’-hydroxycotinine, but not for nicotine or the 3HC/COT ratio. However, these changes were within analytical (i.e. equipment) variation resulting in little within-sample variation (CV≤5.8%) for all analytes in smokers saliva. Conclusions Varenicline, the other analytes and the 3HC/COT ratio remained stable in saliva during storage for 21 days at all temperatures tested and after repeated freezing and thawing with only minor changes in concentration over time. These findings support the potential use of mail-in approach for saliva samples in varenicline smoking cessation clinical trials. Implications Assessing saliva varenicline concentrations can be useful for the evaluation of adherence in smoking cessation trials. Saliva is a non-invasive matrix suitable for mail-in specimen collection. This is the first investigation of stability of varenicline in saliva. Varenicline, nicotine, cotinine, 3’-hydroxycotinine and 3HC/COT were stable in saliva for up to 21 days at room temperature (~25°C), 4°C and -80°C, supporting the use of a mail-in approach for saliva specimen in smoking cessation trials.

scholarly journals STUDIES ON OXIDATION AND REDUCTION BY PNEUMOCOCCUS

1924 ◽  
Vol 39 (3) ◽  
pp. 357-366 ◽  
Author(s):  
Oswald T. Avery ◽  
James M. Neill
Keyword(s):  
Yeast Extract ◽  
Room Temperature ◽  
Prolonged Exposure ◽  
Freezing And Thawing ◽  
Peroxide Formation ◽  
Cell Extracts ◽  
Repeated Freezing ◽  
Phosphate Solutions ◽  
Animal Tests

In the present paper methods have been described for the preparation of sterile extracts of pneumococci. These extracts may be obtained by dissolving the bacteria in broth cultures by means of bile, or by extraction of the cellular substances by repeated freezing and thawing of broth or saline suspensions of unwashed cells. Under special precautions these extracts may be passed through Berkefeld filters without loss of potency. In this procedure, as in all other manipulations incident to their preparation, the extracts should be protected as far as possible from contact with air. All extracts were proved sterile by cultural and animal tests. Sterile extracts of unwashed pneumococcus cells promptly form peroxide on exposure to air. Peroxide formation is almost as active in extracts aerated at 2°C. as in those exposed to the air at room temperature. Detectable amounts of peroxide may be produced by these cell extracts within the reaction range of pH 5 to 9, the optimal zone lying at reactions less acid than pH 6. The peroxide-forming activity of the extracts is gradually diminished by prolonged exposure to 55°C., and is completely destroyed by heating at 65°C. for 5 minutes. Cell extracts of pneumococci which have been thoroughly washed prior to extraction in salt or phosphate solutions exhibit no peroxide-forming activity. These extracts of washed cells may be activated by the addition of the cell washings, yeast extract, or muscle infusion.

Effect of storage temperature and shaking rate on pH and blood-gas results for two quality-control products.

1988 ◽  
Vol 34 (9) ◽  
pp. 1910-1912 ◽  
Author(s):  
K W Ryder ◽  
S J Jay ◽  
M R Glick ◽  
J R Woods
Keyword(s):  
Quality Control ◽  
Room Temperature ◽  
Storage Temperature ◽  
Control Program ◽  
Blood Gas ◽  
Quality Control Program ◽  
Storage Temperatures

Abstract Directions for pre-analytical handling of ampules of two commercially available aqueous quality-control products (contrlL and G.A.S.) contain vague instructions such as "store at room temperature" and "shake vigorously" before analysis. We examined the effect of different storage temperatures (25, 31, and 38 degrees C) and shaking rate (one, two, and four shakes per second) on pH and blood-gas results. For both products, increasing the storage temperature significantly decreased pO2 results, the magnitude of the bias being greatest for those solutions with the highest O2 tensions. However, increasing the shaking rate partly offset this bias. Increasing storage temperature also decreased results for pCO2 and increased results for pH for both manufacturers' ampules with the highest CO2 tensions, and this bias was not offset by increasing the shaking rate. We conclude that both storage temperature and shaking rate must be precisely defined and carefully monitored before these products are used in a quality-control program.

scholarly journals Long-term stability of clinically relevant chemistry analytes in pleural and peritoneal fluid

2020 ◽  
Vol 30 (2) ◽  
pp. 234-241
Author(s):  
Lara Milevoj Kopcinovic ◽  
Marija Brcic ◽  
Jelena Culej ◽  
Marijana Miler ◽  
Nora Nikolac Gabaj ◽  
...  
Keyword(s):  
Peritoneal Fluid ◽  
Room Temperature ◽  
Storage Period ◽  
Total Proteins ◽  
Long Term Stability ◽  
Time Periods ◽  
The Stability ◽  
Stability Limits ◽  
Storage Temperatures

Introduction: Our aim was to investigate the stability of clinically relevant analytes in pleural and peritoneal fluids stored in variable time periods and variable storage temperatures prior to analysis. Materials and methods: Baseline total proteins (TP), albumin (ALB), lactate dehydrogenase (LD), cholesterol (CHOL), triglycerides (TRIG), creatinine (CREA), urea, glucose and amylase (AMY) were measured using standard methods in residual samples from 29 pleural and 12 peritoneal fluids referred to our laboratory. Aliquots were stored for 6 hours at room temperature (RT); 3, 7, 14 and 30 days at - 20°C. At the end of each storage period, all analytes were re-measured. Deviations were calculated and compared to stability limits (SL). Results: Pleural fluid TP and CHOL did not differ in the observed storage periods (P = 0.265 and P = 0.170, respectively). Statistically significant differences were found for ALB, LD, TRIG, CREA, urea, glucose and AMY. Peritoneal fluid TP, ALB, TRIG, urea and AMY were not statistically different after storage, contrary to LD, CHOL, CREA and glucose. Deviations for TP, ALB, CHOL, TRIG, CREA, urea and AMY in all storage periods tested for both serous fluids were within the SL. Deviations exceeding SL were observed for LD and glucose when stored for 3 and 7 days at - 20°C, respectively. Conclusions: TP, ALB, CHOL, TRIG, CREA, urea and AMY are stable in serous samples stored up to 6 hours at RT and/or 30 days at - 20°C. Glucose is stable up to 6 hours at RT and 3 days at - 20°C. The stability of LD in is limited to 6 hours at RT.

Protective effect of glycerol against the increase in alkaline phosphatase activity of lyophilized quality-control serum.

1977 ◽  
Vol 23 (10) ◽  
pp. 1873-1877 ◽  
Author(s):  
K Tanishima ◽  
Y Minamikawa ◽  
N Yokogawa ◽  
M Takeshita
Keyword(s):  
Quality Control ◽  
Alkaline Phosphatase ◽  
Ethylene Glycol ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Maximum Activity ◽  
Freezing And Thawing ◽  
Practical Applications ◽  
Control Serum ◽  
Repeated Freezing

Abstract We studied the effectiveness of glycerol or ethylene glycol in preventing the increase in alkaline phosphatase activity of lyophilized or refrigerated quality-control serum after reconstitution or repeated freezing and thawing. Control serum reconstituted completely from the lyophilized state with subsequent storage at -20 degrees C showed a considerable decrease in alkaline phosphatase activity immediately after thawing, and a gradual increase in activity on allowing it to stand at room temperature. Adding glycerol or ethylene glycol to the reconstituted serum obviated these changes in activity, glycerol being more effective than ethylene glycol. Reconstituted serum with added glycerol maintained maximum activity before refrigeration during either storage for 30 days or on repeated freezing and thawing. Practical applications of this glycerol-supplemented control serum are discussed.

scholarly journals FACTORS INFLUENCING THE SURVIVAL OF SPIROCHETES IN THE FROZEN STATE

1939 ◽  
Vol 70 (6) ◽  
pp. 639-650 ◽  
Author(s):  
Thomas B. Turner ◽  
Nancy L. Brayton
Keyword(s):  
Room Temperature ◽  
Close Correlation ◽  
Gradual Decrease ◽  
Freezing And Thawing ◽  
Relapsing Fever ◽  
Rapid Cooling ◽  
Factors Influencing ◽  
Duration Of Storage ◽  
Before And After ◽  
Storage Temperatures

Titration experiments made with relapsing fever spirochetes before and after freezing showed the following: 1. With each freezing and thawing there is a slight but regular decrease in virulence, which decrease bears no relation to the duration of storage at – 78°C. Ordinarily infectivity is destroyed by more than 4 refreezings. 2. There was not always close correlation between motility and infectivity. 3. Cooling spirochetes from 0°C. to –78°C. over a 2 to 6 hour period damages them only slightly more than does rapid cooling, but warming from – 78°C. to 0°C. over a 2 to 6 hour period kills most of the organisms. Rapid thawing, as in a water bath, damages the spirochetes less than thawing more slowly, as at room temperature. 4. At storage temperatures of –12°C. and –20°C. there is a gradual decrease in virulence over a period of days or weeks, and by the 6th week the infectivity of the material is markedly reduced.

scholarly journals Investigation of quality indicators and studying the stability of “Propolis-AK” gel for the treatment of acne disease

2019 ◽  
pp. 64-75
Author(s):  
А. I. Tykhonov ◽  
T. G. Yarnykh ◽  
S. G. Bobro ◽  
O. S. Shpychak
Keyword(s):  
Quality Control ◽  
Shelf Life ◽  
Quality Indicators ◽  
Room Temperature ◽  
Storage Period ◽  
Storage Conditions ◽  
Social Adaptation ◽  
Control Methods ◽  
Aluminum Tubes ◽  
The Stability

In modern conditions, the incidence of acne, which is a polymorphic multifactorial disease of the sebaceous glands of the skin, has a tendency to significant growth. Localization of lesions on the face in almost all patients indicates the fact that acne has an effect on their psycho-emotional sphere and social adaptation, which makes this problem urgent and indicates the feasibility of creating new effective domestic medicines for treating this pathology. The aim of the work was to conduct research on the investigation of quality indicators and studying the stability of «Propolis-AK» gel of anti-inflammatory and antimicrobial action for the treatment of acne disease. The objects of research were model test-samples of «Propolis-AK» gel, for which were developed methodic for analyzing the qualitative composition and quantitative content of the active substances – propolis phenolic hydrophobic drug (PPHD) and azelaic acid (AA) in this dosage form, comprehensively allowing to evaluate the quality and criteria for the stability of the gel during the entire storage period for the following indicators: description, identification, homogeneity, tightness of the container, pH, package contents, microbiological purity, quantification. In addition, the requirements for packaging, labeling, transportation, storage conditions and shelf life were included in the draft of quality control methods. According to the results of the study of organoleptic and physical-chemical parameters of the developed «Propolis-AK» gel during storage at two temperature conditions (8‒15 °C and 15‒25 °C), it was found that the test samples of the gel under study remained fairly stable according to the studied indicators for 2 years and 3 months, which allows us to recommend a shelf life of 2 years at room temperature in aluminum tubes for the studied gel. According to the results of research, a specification for «Propolis-AK» gel for external use was developed as a component of the draft of quality control methods for the studied medicine. Studies have been conducted to establish the main indicators and methods of quality control of the developed «Propolis-AK» gel for the treatment of acne disease. According to the results of the tests, a “Specification” was developed, which was included in the draft of quality control methods and experimentally proved the stability of «Propolis-AK» gel prepared in pharmaceutical and industrial conditions for a prescribed shelf life of 24 months when stored in aluminum tubes with an internal lacquer coating in a cool place (8‒15 °C) and at room temperature (15‒25 °C).

Effect of Times to Blood Processing on the Stability of Blood Proteins Associated with Dementia

2020 ◽  
Vol 49 (3) ◽  
pp. 303-311
Author(s):  
Jui-Feng Chang ◽  
Huei-Chun Liu ◽  
H.H. Chen ◽  
Wen-Ping Chen ◽  
Jian-Lin Juang ◽  
...  
Keyword(s):  
Room Temperature ◽  
Amyloid Β ◽  
Blood Proteins ◽  
Blood Draw ◽  
Temperature Plasma ◽  
Blood Samples ◽  
Blood Processing ◽  
The Times ◽  
The Stability ◽  
Storage Temperatures

<b><i>Background:</i></b> The stability of proteins in the collecting tubes after blood draw is critical to the measured concentrations of the proteins. Although the guidelines issued by the Clinical and Laboratory Standards Institute (CLSI) suggest centrifugation should take place within 2 h of drawing blood, it is very difficult to follow these guidelines in hospitals or clinics. It is necessary to study the effect of times to blood processing on the stability of the proteins of interest. <b><i>Methods:</i></b> In this work, the plasma proteins of interest were those relevant to dementia, such as amyloid β 1–40 (Aβ<sub>1–40</sub>), Aβ<sub>1–42</sub>, Tau protein (Tau), and α-synuclein. The times to blood processing after blood draw ranged from 0.5 to 8 h. The storage temperatures of blood were room temperature (approx. 25°C) and 30°C. After storage, blood samples were centrifuged at room temperature to obtain plasma samples. Ultrasensitive immunomagnetic reduction was applied to assay these proteins in the plasma. <b><i>Results:</i></b> The levels of plasma Aβ<sub>1–40</sub>, Tau, and α-synuclein did not significantly change until 8 h after blood draw when stored at room temperature. Plasma Aβ<sub>1–42</sub> levels did not change significantly after 8 h of storage at room temperature before blood processing. Higher storage temperatures, such as 30°C, for blood samples accelerated the significant variations in the measured concentrations of Aβ<sub>1–40</sub>, Tau, and α-synuclein in plasma. <b><i>Conclusion:</i></b> According to these results, for clinical practice, it is suggested that blood samples be stored at room temperature for no longer than 4.5 h after blood draw until centrifugation for the assay of dementia biomarkers in plasma.

scholarly journals Mass Screening Using Saliva Samples and Pooled Testing Strategy For SARS-CoV-2 RT-PCR Detection in Latvia

2021 ◽  
Author(s):  
Didzis Gavars ◽  
Mikus Gavars ◽  
Dmitry Perminov ◽  
Janis Stasulans ◽  
Justine Stana ◽  
...  
Keyword(s):  
Field Study ◽  
Rt Pcr ◽  
Sample Distribution ◽  
Pooled Testing ◽  
Non Invasive ◽  
Specimen Collection ◽  
Invasive Method ◽  
Self Service ◽  
The Stability ◽  
Serial Measurements

Abstract BackgroundThe number of COVID-19 cases is increasing globally and there is an urgency for a simple non-invasive method for the detection of SARS-CoV-2. Our study aimed to demonstrate that saliva can be used as a specimen for SARS-CoV-2 detection notably for the screening of extensive population groups via pooling. MethodsWe performed 36 serial measurements of 8 SARS-CoV-2 positive saliva samples to confirm the stability of the specimen and completed 37 pools of saliva samples by adding one positive specimen per pool. We collected paired nasopharyngeal/oropharyngeal swabs (NPS) and saliva specimens and processed them within 24 hours of collection. To demonstrate that saliva is an appropriate specimen for SARS-CoV-2 detection a field study including 3,660 participants was performed between September 29 and October 1, 2020. A new solution for distribution and collection of self-sampled saliva was designed, produced and installed. All methods were performed in accordance with the relevant guidelines and regulations.ResultsSaliva specimens were stable for testing for up to 24 hours. The results of saliva samples were consistent with those obtained from NPS from the same patient with 90% sensitivity (95% CI 68.3%-98.7%) and 100% specificity during the first two weeks after the onset of symptoms. Using pooling strategy 796 RT-PCR tests were performed. All pools showed 100% positivity in different pooling proportions. Overall, 44 saliva samples (1.2%) tested positive for SARS-CoV-2 during the field study. In total, between September 29 and April 10, 415 673 RT-PCR saliva tests were performed. The contactless self-service terminals were placed in hospitals, factories and municipalities as an additional way to submit self-collected saliva for testing.ConclusionOur findings demonstrate that saliva is an appropriate specimen for pooling and SARS-CoV-2 screening with accurate diagnostic performance. Patient-performed simple specimen collection allows testing an extensive number of people rapidly, obtaining results of the spread of SARS-CoV-2 and allowing authorities to take timely measures. Automated sample distribution and collection points are accessible 24/7 allowing safe, contactless and more efficient way to submit various kind of samples for testing.

scholarly journals The Effects of “Dry Swab” Incubation on SARS-CoV-2 Molecular Testing

2021 ◽  
Author(s):  
Bijal A Parikh ◽  
Meghan A Wallace ◽  
Broc T McCune ◽  
Carey-Ann D Burnham ◽  
Neil W Anderson
Keyword(s):  
Room Temperature ◽  
Molecular Testing ◽  
Liquid Media ◽  
Liquid Transport ◽  
Viral Transport ◽  
Specimen Collection ◽  
Safety Risks ◽  
Positive Specimen ◽  
The Stability ◽  
Roche Cobas

Abstract Background Widespread testing of SARS-CoV-2 has resulted in shortages of collection devices and transport media. We evaluated the stability of flocked swabs inoculated with SARS-CoV-2-containing specimen incubated dry (i.e., without transport medium) at room temperature. Methods A pool of SARS-CoV-2 positive specimen was used to inoculate flocked swabs. Five swabs were placed immediately into universal transport media (UTM) following inoculation, and tested immediately (day 0). Fifteen of the swabs were placed into sterile 15-mL conical tubes and incubated at room temperature for 1, 2, or 7 days. Following incubation, swabs were hydrated in separate vials of UTM and tested. This protocol was repeated for viral transport media (VTM) and saline. As a comparison, a series of swabs was prepared and tested in parallel, but stored in the corresponding liquid transport media (UTM, VTM, or saline) and incubated at room temperature. Testing was performed at 1, 2, and 7 days postinoculation in duplicate. All molecular testing was performed using the Roche cobas SARS-CoV-2 assay. Results All dry swabs tested on days 1, 2, and 7 provided results that were within 2 cycle thresholds (CTs) of the average CT values for swabs hydrated in the same media and tested on day 0. There was no statistical difference in CT values between swabs incubated in liquid media versus dry swabs incubated at room temperature prior to hydration in liquid media. Conclusions The utilization of “dry swabs” may simplify specimen collection, negate the need for liquid transport media, and mitigate safety risks while preserving the accuracy of testing.

scholarly journals Stability of Antibiotics for Intraperitoneal Administration in Extraneal 7.5% Icodextrin Peritoneal Dialysis Bags (Stab Study)

2016 ◽  
Vol 36 (4) ◽  
pp. 421-426 ◽  
Author(s):  
Dwarakanathan Ranganathan ◽  
Saiyuri Naicker ◽  
Steven C. Wallis ◽  
Jeffrey Lipman ◽  
Sharad K. Ratanjee ◽  
...  
Keyword(s):  
Peritoneal Dialysis ◽  
Room Temperature ◽  
Intraperitoneal Administration ◽  
Stability Studies ◽  
Initial Value ◽  
Time Intervals ◽  
Storage Duration ◽  
Different Temperatures ◽  
The Stability ◽  
Drug Free

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.

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