FAQs

STRUCTURAL/BINDING ANALYSIS 

Q1. What is the difference between DSF and DSC? 

DSF uses a hydrophobic fluorescent protein dye to monitor the unfolding as a function of temperature while DSC compare the heat required to change the temperature between sample and reference. DSF uses 100 µg of sample and can be performed in a high throughput manner (48 samples at a time) while DSC uses 1 mg of sample and 1 samples can be performed at a time. 


Q2. What is the variability of the Baculovirus particles (BVP) ELISA? How can we confidently know our samples fall below the cutoff? 

Aliquots from the same batch of BVP are expected to provide consistent results. We have established an assay acceptance criterion to QC each of our BVP preps as batch-to-batch variation is known to affect BVP assays. 

 

Q3. Does freezing/thawing of the baculovirus particles (BVP) affect the assay performance? 

Freezing/thawing can affect the assay performed but our BVP prep is kept stored frozen in small aliquots to avoid multiple freeze/thaw cycles. The small aliquots from the same batch have been shown to provide consistent results even after storage at -80C for up to a year. 

 

Q4. Does LakePharma offer SEC-MALS, MALDI (MS), circular dichroism (CD)?  

LakePharma does not offer SEC-MALS, MALDI, or circular dichroism at this time. 


MASS SPEC ANALYSIS 

Q1. What conditions does LakePharma perform for intact mass?  

LakePharama can include non-reduced or reduced (by DTT) and/or deglycosylation (by PNGase F). 


Q2. Does LakePharma offer protein sequencing?  

LakePharma provides De Novo antibody sequencing, and sequence confirmation by single/double enzyme digestion. 


Q3. Can LakePharma perform multiple enzymes (protease digestions) for sequence confirmation/peptide mapping/PTM analysis?  

LakePharma can include multiple enzymes for sequence confirmation and peptide mapping. Our standard only includes trypsin and/or chymotrypsin. Any other enzymes to be included will need to be provided or purchased as passthrough. 


Q4. Is LakePharma able to perform assays to verify the site of disulfide bond linkages?  

Yes, LakePharma can perform cysteine analysis of disulfide bond sites and linkages by disulfide mapping analysis. 


Q5. Is LakePharma able to perform O-glycan analysis?  

No, due to the variability and lack of specific motif of O-glycans, LakePharma does not perform any O-glycan analysis. 


Q6. Can you tell me what the implications are of pyroglutamate formation on the N-termini of IgGs?  

Pyroglutamate is a very common post-translational modification in mammalian expression when the N-terminal starts with a Q. It typically does not affect the bioactivity of the antibody. 


MATERIALS REQUIREMENTS 

Q1. What is the minimum amount and concentration required for these analyses: CE-SDS, cIEF, SE-UPLC, etc?  

  • CE-SDS (non-reducing & reducing): 100µg of purified protein at ≥ 1mg/mL 
  • cIEF: 100µL of purified protein at ≥ 2mg/mL 
  • SE-UPLC: 100 µL of purified protein at ≥ 1mg/mL 
  • DSC: 1 mL of purified protein at ≥ 1mg/mL; 10mL blank buffer formulation 
  • DSF: 100 µL of purified protein at ≥ 1mg/mL; (Optional) 10mL blank buffer formulation 
  • N-Glycan Analysis by CE: 100µg of purified protein at 1.5mg/mL to 7.5mg/mL 
  • N-glycan Analysis by LC-MS: ≥ 100µg of purified protein at ≥ 1mg/mL 
  • Polyspecificity Analysis: 200 µg per purified sample at ≥ 1 mg/mL 
  • Octet: 100 µg of antigens per plate performed (assuming MW ~100 kDa). We typically do not perform Octet if antigen size is <15 kDa due to low sensitivity. 


Q2. Is there a buffer requirement or restriction? 

Yes, LakePharma does have a buffer requirement and restriction specific to each of our analytical assays. In general, we would avoid samples that contain detergents and organic solvents.  


TIMELINE 

Q1. How much is it to expedite the bioanalytical assay?  

Expediting bioanalytical projects will provide guaranteed timeline shortened timeline compared to standard. There will be an extra fee based on the total project cost to expedite the project. Please inquire to discuss further.