To avoid cross-contamination in qPCR, key practices include: separating pre- and post-amplification areas with dedicated equipment, using a unidirectional workflow, including a “no template control” in each run, properly cleaning work […]
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Reduce the risk of cross-contamination from the amplicon/template and previous reactions for a qPCR
Use a unidirectional workflow during experiment setup. Separating pre- and post-amplification areas is key to preventing contamination. Prepare your PCR master mix in a template-free room (see next bullet) using reagents that never […]
Difference between dye-based vs probe-based qPCR
Dye-based qPCR is less expensive than probe-based qPCR, but probe-based qPCR is more specific and accurate. The choice between the two depends on the research goals and the type of […]
OmpA Signal for Protein Expression
The OmpA signal peptide is a 21-amino acid sequence that targets fused proteins to the Sec secretion pathway in E. coli. It can be used to increase protein yield and simplify purification […]
Isopycnic Centrifugation
In isopycnic separation, also called buoyant or equilibrium separation, particles are separated solely on the basis of their density. Particle size only affects the rate at which particles move until […]
High-cell-density cultivation (HCDC)
High-cell-density cultivation (HCDC) is a process that improves the formation of microbial biomass and products. It can be used for microorganisms such as bacteria, archaea, and yeasts. HCDC can make the fermentation process […]
Is Kozak sequence essential for transgene expression in lentivirus?
Yes, a Kozak sequence is essential for efficient translation and transgene expression in lentiviruses: In addition to the Kozak sequence, a woodchuck post-transcriptional regulatory element (WPRE) can also be added […]
Primers and probes used for rAAV quantitative analysis
Applicability Target Sequences UniversalAll rAAV samples ITR2 primers: 5′-ggaacccctagtgatggagtt-3′ and5′-cggcctcagtgagcga-3′;probe: R-5′-cactccctctctgcgcgctcg-3′-Q. Semi-universalGroup of rAAV samples CMV promoter primers: 5′-ttcctacttggcagtacatctacg-3′ and5′-gtcaatggggtggagacttgg-3′;probe: R-5′-tgagtcaaaccgctatccacgccca-3′-Q;and other sequences. CAG promoter primers: 5′-ctgaccgcgttaatcccaca-3′ and5′-acaagccgtgattaaaccaaga-3′. CBA promoter […]
Quantification for residual host cell DNA contamination in the rAAV prep via qPCR or ddPCR analysis targeting highly repetitive genome sequences
DNA Impurity Target Sequences Plasmid KanR primers: 5′-gggcgcccggttctttttgtc-3′ and5′-gccagtcccttcccgcttcagtg-3′. AmpR primers: 5′-cgcgccacatagcagaactt-3′ and5′-cgccccgaagaacgttt-3′;probe: R-5′-aaaagtgctcatcattg-3′-Q;and other sequences. Adenovirus E2A primers: 5′-ttgctgaaacccaccatttg-3′ and5′-tcgtggacagcgaggaaga-3′;probe: R-5′-cgccacatcttctct-3′-Q. Adenovirus E4 primers: 5′-tcggcgcactccgtaca-3′ and5′-cgcgggtctctgtctcaaaa-3′;probe: R-5′-tagggatcgcctacctc-3′-Q. HSV UL23 […]