Test your peptides at BTLabs
2,893 tests published across 30 peptides from 335 vendors
first test 22 Jul 2025 · latest 24 Sep 2026
All partner labs →Pass rate on the most recent 200 tests under Finnrick’s Purity Focus methodology
Pass rate on the most recent 200 tests under Finnrick’s Purity Focus methodology
Add Endotoxins and other options with our Standard testing.
About BTLabs
- Tests published
- 2,893
- Latest test
- 24 Sep 2026
- Location
- West Palm Beach, FL
- Instrumentation
- HPLC-FTIR
BTLabs is an analytical laboratory in West Palm Beach, Florida, with a pharmaceutical-testing heritage spanning more than 25 years. Finnrick partners with the lab for independent peptide testing — every sample is analyzed on calibrated, professionally operated equipment and returned as a formal Certificate of Analysis (COA) documenting exactly what was found.
See how BTLabs answered our methodology questionnaire and how it compares to other partner labs.
Methodology Questionnaire
Responded 8 Jan 2026
A) Quantification Basis
1. Is reported quantity based on absolute calibration against a reference standard, or relative/normalized signal?
Our quantification is typically performed using a known reference standard. This involves creating a calibration curve in which the detector response (peak area) is plotted against known concentrations to confirm linearity. The signal itself is “normalized” by the software, as it calculates the peak area for each signal and reports it as an overall percentage. However, to be clear, we do not manually normalize the HPLC trace beyond this software-based processing.
2. Do you average replicate injections or preparations before reporting a single value?
In research, it is common practice to average the values from repeated measurements of the same sample to obtain statistical information, such as percent error or standard deviation. However, we do not do this for every sample, as it would significantly increase both testing time and cost. Instead, we perform a weekly analysis of a well-characterized material (caffeine), acquiring multiple measurements that provide statistical information about the instrument’s performance. This approach allows evaluation of the method, as well as key components such as the lamp and the column, and is standard practice in many analytical laboratories.
B) Sample Preparation
3. Do you assume full recovery of peptide upon reconstitution, or do you measure recovery implicitly?
We generally assume full recovery upon reconstitution of the lyophilized peptide unless there is clear evidence of poor solubility or degradation (for example, abnormal peak shape or shoulders in the chromatogram). However, recovery is implicitly verified by assessing the total chromatographic area and confirming the expected retention behavior.
4. Do you correct for adsorption, losses, or degradation, or are these reflected in the final number?
No artificial corrections are applied for adsorption or degradation. Any losses during handling, vial adsorption, or solution instability are directly reflected in the final measured value and in the peak shape (by UV or FTIR). In other words, the reported value represents what is actually present and recoverable, rather than an idealized theoretical amount. We try our best to ensure those losses are close to zero.
C) Detection & Calculation
5. Which detector(s) are used for quantification (UV, MS, both), and which signal is authoritative for quantity?
Quantification is primarily performed by UV absorbance (HPLC-UV) because it provides direct, linear response proportional to peptide bond content. Mass spectrometry (MS) is used as a confirmatory tool to verify identity and look for impurities or degradation products, but not as the main signal for quantitative yield due to matrix and ionization variability.
6. How is purity incorporated into quantity (e.g., normalization vs independent measurement)?
Purity is determined separately, by HPLC peak area or by MS profile integration, and used to refine the total quantity. For instance, a sample showing 98% main peak purity means that 98% of the measured UV-derived mass corresponds to the desired peptide. But the final “mg per vial” is calculated as the Mass of vial contents × HPLC purity fraction (reason why we weight the contents of each vial shipped to us).
D) Precision & Uncertainty
7. What is your stated margin of error for this peptide, and does it include preparation + calibration uncertainty?
Typical analytical uncertainty for peptide quantification is ±2–3% when using calibrated HPLC-UV detection under controlled conditions (validated linear range, stable baseline, and a pure reference standard). This includes injection repeatability, calibration curve fitting, and weigh-in precision. Everything in research has a level of error attached to it, not only from the human factor involved, but also the instrumentation. Nothing is 100% accurate.
8. Are reported values rounded, truncated, or raw calculated outputs?
Reported values are rounded to one or two significant digits based on the method’s precision and the instrument sensitivity. A high resolution instrument might be able to provide 3–4 significant figures. For example, a result calculated as 0.987 mg per vial might be reported as 0.99 mg/vial. Raw data are preserved in records but not shown in formatted reports unless requested. Since reporting more significant figures than we can will be a lie.
E) Interpretation
9. Does your reported “mg per vial” represent recovered mass, inferred mass, or label-equivalent mass?
Our “mg per vial” value represents the recovered, quantifiable peptide mass as determined by comparison to a reference standard and corrected for purity. It is not a dry-weight label claim or theoretical yield; it reflects the actual peptide that can be dissolved and detected under the analytical conditions used.
10. Under what conditions would you expect two vials from the same batch to differ by <1%?
For properly filled, homogeneous lots, variation between vials is typically expected to be below 1%, but there are several practical limitations to achieving this ideal level of consistency. These include balance tolerance, lyophilization uniformity, solubility, excipient formulation, and human error, among others. Greater differences can also arise from moisture uptake, static effects, incomplete reconstitution, or sample degradation. To better understand and monitor instrument-related variability, we routinely run our caffeine/uracil OQ to assess performance over time.
What you’ll learn
BTLabs runs your samples through HPLC analysis, and sends back a certificate of analysis, detailing test results. Computed through your choice of Finnrick safety standards, this sample is then declared as “passing” or “failing”, depending on the answers to three critical questions:
Identity
Is this actually what the label claims, or something else entirely?
Purity
Are there other peptides, proteins, or contaminants mixed in with your compound?
Quantity
Did you receive the amount of active ingredient you paid for, or are you dosing based on wishful thinking?
HPLC is the standard analytical method for peptide characterization, used across research institutions and commercial labs worldwide.
Tests BTLabs can run
Identity, Purity & Quantity
Required BasicConfirms it’s the right compound, at full strength, and only this compound — by HPLC.
Custom orders start at $79 per sample, including Basic and any product surcharge. Prices vary by product and lab.
Endotoxins Testing
From +$110Bacterial toxins can trigger fever or adverse reactions in the body.
Custom orders including this test start at $189 per sample, including Basic and any product surcharge. Prices vary by product and lab.
Heavy Metals Panel
UnavailableTraces of arsenic, cadmium, mercury and lead can build up in the body over time.
Learn about this test; online ordering is currently unavailable.
Residual Solvents
UnavailableLeftover solvents from synthesis can be toxic if they weren’t fully purged.
Learn about this test; online ordering is currently unavailable.
Sterility Testing
UnavailableChecks the vial is free of bacterial and fungal contamination.
Learn about this test; online ordering is currently unavailable.
Peptides BTLabs can test
How Finnrick publishes results
Finnrick publishes results when we can establish sample provenance and have enough evidence that the sample represents the product sold by the named vendor. Published results include vendor and product details, helping customers evaluate the available evidence and encouraging better supply-chain decisions.
Results that do not meet these requirements are shared with the requester and kept outside the public record. Read how Finnrick decides which results to publish →
Don’t want to share sample details?
The Confidential option costs an additional $99 per sample in Custom, on top of Basic testing, any product surcharge and selected tests. Standard already includes Confidential. Results are shared with you and not published publicly.
Frequently asked questions
Can I test my peptides at BTLabs?
Choose BTLabs in Custom when it is available for your product and selected tests. The current options are shown below. The Confidential option is a paid Custom add-on and is included in Standard.
What does BTLabs test for?
See the current test options on this page. Availability and total price depend on your product, lab and selected tests; Basic testing is required.
Are BTLabs results independent and trustworthy?
Samples sent through Finnrick are anonymized before they reach the lab. Finnrick reviews lab performance using overlapping results and independently obtained anchor samples. Results are published only when sample provenance meets Finnrick's publication requirements.
How many BTLabs test results has Finnrick published?
2,893 published results to date, across 30 peptides and 335 vendors. However, not all tests Finnrick has commissioned from this lab have been published: more about our publishing policy.
Add Endotoxins and other options with our Standard testing.
Do you distribute peptides?
Finnrick offers professional testing services for vendors who want to verify their supply chain and build trust with customers through independent quality assurance.
Learn about vendor services