Ethylenediaminetetraacetic acid blood samples were collected at weeks 12, 24, and 48; and 50 microlitres of whole blood was pipetted onto Whatman 903 Proteinsaver cards which were dried overnight and then stored in airtight freezer-safe bags at -80°C. An indirect method for quantifying TFV-DP was used, which has been validated at the Division of Clinical Pharmacology, University of Cape Town.18 (link) It consists of solid phase separation of tenofovir and TFV-DP, enzyme dephosphorylation of TFV-DP to tenofovir, and then high-performance liquid chromatography with tandem mass spectrometry to detect tenofovir.18 (link) Dolutegravir trough concentrations were sampled 12±2 hours after the last dose for participants on supplemental dolutegravir, and 24±4 hours for participants receiving TLD only.17 (link) Dolutegravir concentrations in plasma were analysed by liquid-liquid extraction in a method validated by the Division of Clinical Pharmacology, University of Cape Town.19 (link) For TFV-DP concentrations, the lower limit of quantification (LLQ) is 16.6 fmol/punch and for dolutegravir concentrations the LLQ is 0.03 μg/mL. Viral loads were measured using Abbott Realtime® HIV-1 polymerase chain reaction assay (Abbott Molecular, Des Plaines, IL), which is able to quantify virus ribonucleic acid over a range of 20 to 107 copies/mL.
903 protein saver card
Manufactured by Cytiva
Sourced in United Kingdom
903 Protein Saver Cards are a type of filter paper used for the collection, transport, and storage of dried blood samples. The cards provide a convenient and reliable method for preserving protein samples for subsequent analysis.
Automatically generated - may contain errors
Lab products found in correlation
Whatman, by Cytiva (68 mentions)
Whatman 3 filter paper, by Cytiva (1 mentions)
Qiaamp dna investigator kit, by Qiagen (1 mentions)
Geneamp pcr system 9700, by Thermo Fisher Scientific (1 mentions)
Sodium heparin vacutainer, by BD (1 mentions)
Etrex, by Garmin (1 mentions)
Quickplex sq 120, by MSD (1 mentions)
Diluent 100, by MSD (1 mentions)
Edta microvette, by Sarstedt (1 mentions)
Floqswab, by Copan (1 mentions)
Qiaamp blood midi kit, by Qiagen (1 mentions)
Cobas ampliprep, by Roche (1 mentions)
Biopsy punch, by Integra LifeSciences (1 mentions)
Clot activator, by BD (1 mentions)
69 protocols using 903 protein saver card
1
Quantifying Antiretroviral Pharmacokinetics
2
Dried Blood Spot Protocol for Quantification
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
DBS standards and QCs were prepared by carefully spotting exactly 50 μL of whole blood standards and QCs on each circle of Whatman 903 Protein Saver Cards. DBMS standards and QCs were similarly prepared by spotting 30 μL of breast milk standards and QCs. Spotted cards were left to dry at room temperature overnight and stored with dessicant sachets in ziplock bags at −80 °C.
3
Quantifying TFV-DP in Dried Blood Spots
4
Dried Blood Spot Collection Protocol
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
The day of blood sampling, the participants were allowed to take their usual drug therapies and had no dietary restrictions. Whole blood was collected using finger puncture, while the patient was sitting in a quiet environment, followed by deposit of a drop of blood (20 μL) on a blotting paper (Whatman 903 protein saver cards™) and dried overnight at room temperature to obtain dried blood spot. Then, the blot spots were stored at room temperature and shipped to the Laboratory of Biochemistry of Timone Hospital for analysis.
5
Dried Blood Spot Biomarker Analysis
6
Dried Blood Spot Collection and Storage
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Using 1.8-mm lancets, up to 4 drops of blood were collected from participants and applied to Whatman 903 Protein Saver Cards. The cards were kept on drying racks inside plastic boxes to allow them to dry for at least 4 hours. The cards were subsequently stored in individual, sealed plastic bags with a 5 g silica gel desiccant sachet to protect against humidity and a humidity-monitoring card for up to 2 weeks. Humidity monitoring cards were checked daily. DBS samples were transported to Centers for Disease Control and Prevention (CDC) laboratories in the United States, where they were stored at −20°C until testing.
7
Dried Blood Spot Extraction Protocol
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Dried blood spot extraction was adapted from a previously reported method.16 (link) Dried blood spot was prepared by depositing 10 μL of parasitized whole blood onto Whatman 903 protein saver cards. The spots were allowed to air-dry for a minimum of 4 hours, removed using a 6-mm biopsy punch, and placed in 2-mL microcentrifuge tubes (one spot per tube). Next, 200 μL of phosphate-buffered saline (PBS) with 0.1% Tween-20 (PBST) was added to each tube. The tubes were vortexed at 3,200 rpm for 10 minutes and then placed in a mini-centrifuge for 30–60 seconds. The supernatant was removed and saved for analysis.
8
Breast Milk Protein Saver Card Spotting
9
Dried Blood Spot Collection and Analysis
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Dried blood spots will be collected using a single heel/finger prick at the enrollment and week 4 follow-up visits (Table 5 ). Less than 0.5 mL of blood will be collected from all enrolled children for a dried blood spot on Whatman® 903 protein saver cards, which will be used for eventual descriptive seroepidemiology of preexisting immunity against Shigella and description of immune responses to infection [47 ]. Cards will be fully dried at room temperature for a minimum of 2 hours, then placed in a plastic bag and refrigerated at 4°C for long-term storage.
10
Malaria Surveillance in Northern Brazil
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Samples and survey data were collected continuously from March 2016 to September 2018 in Boa Vista and Pacaraima. In Rorainópolis samples were collected in a single survey in 2018. Patients were approached for their willingness to participate in the study as they exited the malaria testing post after they had a routine malaria diagnosis by microscopy. The participants were recruited if they were coming from the health post where they had come to seek a malaria diagnosis and if they consented to participate in the study. All malaria positive patients were treated with antimalarial drugs, according to the Brazilian national therapeutic guidelines for malaria. Written informed consent was obtained from all participants. Consented individuals were asked to complete a questionnaire which was used to collect demographic data and travel history. Information about the patient’s country of residence, occupation, where the patient had lived in the last 15 days, whether they had travelled out of Brazil in the last 30 days and their travel destination. A 10 ml venous blood sample was obtained from each participating individual from which thin and thick blood smears and dried blood spots (DBS; Whatman 903 Protein Saver Cards) were prepared.
About PubCompare
Our mission is to provide scientists with the largest repository of trustworthy protocols and intelligent analytical tools, thereby offering them extensive information to design robust protocols aimed at minimizing the risk of failures.
We believe that the most crucial aspect is to grant scientists access to a wide range of reliable sources and new useful tools that surpass human capabilities.
However, we trust in allowing scientists to determine how to construct their own protocols based on this information, as they are the experts in their field.
Ready to get started?
Sign up for free.
Registration takes 20 seconds.
Available from any computer
No download required
Revolutionizing how scientists
search and build protocols!