Home › Learn › Blog

Notes from the bench

Buying, handling and research-design questions answered first, then explained. Every post links to the certificate for any product it mentions.

All posts 70 Compound background 9 Buying 13 Certificates 3 Reference 24 Handling 5 Research design 15 Comparisons 1

Three compounds mapped to two receptors on a pituitary cell, with their sizes and durations

Research design · 11 September 2026

Ipamorelin vs CJC-1295 vs tesamorelin: three growth hormone axis compounds compared

Three research compounds act on the growth hormone axis by two different routes. Ipamorelin is a five-residue secretagogue at the GHS receptor; CJC-1295 and tesamorelin are GHRH analogues at the GHRH receptor, one long-acting through albumin binding and one through an N-terminal modification. Receptor, size, duration and the literature for each, and how the three combine in a design.

Read the post →

A vetting worksheet beside a labelled vial and a certificate of analysis

Buying · 11 September 2026

How to vet a research peptide supplier before you order

Seven checks that separate a supplier who tests every lot from one who copies a certificate: lot-matched COAs, a named lab, LC-MS identity, net peptide content, endotoxin, a real address, and how they talk about use. With a worksheet, an example support exchange, and the FDA's own test for intended use.

Read the post →

A sealed peptide vial in a padded mailer beside an analytical report with a verification code

Buying · 11 September 2026

How to get a peptide independently tested

Any researcher can send a sealed vial to an independent analytical lab and get purity by HPLC, identity by mass spectrometry and the milligrams actually in the vial back within about a week. What it costs, what to send, how to read the result against the supplier's certificate, and what to do when they disagree.

Read the post →

A methods paragraph with each reported field highlighted, beside a certificate and a labelled vial

Reference · 11 September 2026

How to report a research peptide in a methods section

A reviewer should be able to reconstruct exactly what was in the vial and what reached the assay. That takes eleven facts: supplier, product, lot, purity with method, identity with method, net peptide content, salt form, endotoxin, storage, reconstitution and vehicle. What each one is for, a template paragraph, and what NIH expects for key chemical resources.

Read the post →

A close-up of a lyophilized peptide vial label with each field called out

Buying · 11 September 2026

How to read a research peptide vial label

A research peptide label carries seven fields that matter: compound name, net amount, lot number, purity claim, storage instruction, the research-use statement and the supplier. What each one should say, how to check it against the certificate, a worked label-to-certificate comparison, and the three things a label cannot tell you.

Read the post →

A peptide chain growing on a resin bead through repeated deprotection and coupling cycles, ending in cleavage and purification

Reference · 11 September 2026

How research peptides are made: solid-phase synthesis and where the impurities come from

Almost every research peptide is built by solid-phase synthesis, one residue at a time on a resin bead, then cleaved, purified by HPLC and freeze-dried. Each step leaves a characteristic impurity, and each impurity shows up on a specific line of the certificate. The six steps, the yield arithmetic, what a crude chromatogram looks like, and the map between the two.

Read the post →

A cell culture plate beside a certificate with the endotoxin line highlighted and a dilution calculation

Reference · 11 September 2026

What the endotoxin line on a peptide certificate means for cell work

Endotoxin is a bacterial residue that survives filtration and freeze-drying and can trigger immune and inflammatory responses in cultured cells on its own. The certificate reports it in endotoxin units per milligram. How the test works, a dilution table for every catalog vial, which cell types care, and when the number matters.

Read the post →

A reconstitution table beside a vial and a 1 mL insulin syringe marked in units

Reference · 11 September 2026

Concentration and syringe-unit table for every catalog vial

Every vial in the catalog reconstituted at 1, 2 and 3 mL, with the resulting mg/mL, micrograms per insulin-syringe unit, and the draw for a 250 mcg aliquot. Plus the molar concentration from PubChem weights, and the two vials that need a different approach.

Read the post →

Two sequences side by side, one with a Drug Affinity Complex linker attached, beside a certificate mass line

Research design · 11 September 2026

CJC-1295 with DAC vs without DAC: what the name means and how to tell which you have

Two different compounds are sold under the name CJC-1295. One carries a Drug Affinity Complex that binds albumin and acts for days; the other is the bare 29-residue GRF analogue that acts for minutes. What the difference is, how the literature describes each, and how the certificate tells them apart.

Read the post →

A bacteriostatic water vial, a sterile water vial and a culture plate, with a dilution calculation

Research design · 11 September 2026

Bacteriostatic water and benzyl alcohol: when the preservative gets into your cell work

Bacteriostatic water is sterile water with 0.9% benzyl alcohol added to stop microbial growth in a vial drawn from repeatedly. Benzyl alcohol is not inert to cultured cells. What the preservative is for, how much of it reaches a culture at each dilution, when to use sterile water or buffer instead, and how to control for it.

Read the post →

Guides, not just posts

The blog covers buying, handling and research-design questions as they come up. The evergreen material lives in the guides: reading a certificate of analysis, storage and stability, one research guide per compound and the glossary.

New posts publish to the RSS feed. Every post is written for laboratory research use only and links to the lot certificate for any product it mentions.

Notes from the bench

Posts

Guides, not just posts

Subscribe

Restock alerts and new lot reports, by email