K4 Elite
K4 Elite
The research resource hub for K4 Elite: the cited Research Trials literature index, the laboratory calculators, and the storage and primary-source reference material — all in one place. Everything here is reference material or a measurement aid; nothing on this page or the pages it links to is a protocol or a dosing recommendation.
A cited index of what has actually been studied for each compound listed on this site: the populations published trials enrolled, the regimens those studies administered to their own participants or animal models, the adverse effects that were reported, and the interactions and trial contraindications recorded in the literature.
Every entry is written as historical record of how a study was conducted — not as a protocol, not as instructions, and not as guidance for human or veterinary use. Findings are reported without interpretation, and each trial, adverse effect and interaction is shown with the primary source it came from; rows without a citation are not published.
One or more randomised controlled trials in humans have been published. Includes compounds with an approved product label.
Human data exist but are limited to small, uncontrolled, open-label or observational studies.
Published work is confined to animal models and in-vitro systems. No controlled human trial of the compound has been published.
A multi-component preparation. No controlled study of the combination has been published; the literature covers the individual components only.
Pick or type the vial size and diluent volume, set the amount to measure, and the tool returns the concentration and the exact draw — in mL (= cc) and in syringe units for the syringe you're using. 1 cc = 1 mL; they are the same volume.
Instant two-way conversions for the units that come up constantly at the bench. Type in either box of a pair and the other updates live.
A cubic centimetre and a millilitre are the same volume — "cc" is just the older name still printed on some syringes. Nothing to convert: 1 cc = 1 mL, always.
1 milligram = 1,000 micrograms. (mcg and µg are the same unit.)
On any U-100 syringe (1.0, 0.5 or 0.3 mL), 1 unit = 0.01 mL, so mL × 100 = units.
Mass-to-units depends on how the vial was reconstituted. Set the solution concentration, then convert either way.
The milligram figure printed on a lyophilised vial is usually a gross weight. Synthetic peptides are typically isolated as salts — most often trifluoroacetate (TFA) from reverse-phase HPLC purification, sometimes acetate or hydrochloride — and the bound counterions plus residual water are weighed along with the peptide. A certificate of analysis normally reports two separate numbers: net peptide content — the actual peptide mass in the vial, in milligrams (often noticeably less than the labelled weight, and usually determined by amino-acid analysis or nitrogen content) — and HPLC purity (the percentage of that peptide material which is the target sequence rather than deletion or truncation products). Enter the net content in mg exactly as the COA states it; purity then trims it to the true mass of target peptide.
Skipping this correction is one of the most common sources of silent error in peptide work: two vials with identical labels but different salt forms can differ by 20 % or more in actual peptide mass, which propagates straight into every downstream concentration. Anchoring calculations to the COA figures rather than the label is what makes results reproducible between lots and between laboratories.
In-vitro work is specified in molar terms, not mass terms — receptor occupancy, EC50 and IC50 values in the literature are all molar. Converting a weighed mass to a molarity requires the molecular weight of the compound; molecular weights for catalogue items are listed in the molecular-data table on each product page and in the Peptide Research Library. Where a peptide is supplied as a salt, use the free-base molecular weight together with the net-peptide-corrected mass from the calculator above.
General laboratory handling practice for lyophilised research peptides. Compound-specific guidance on the certificate of analysis or product page always takes precedence — stability varies substantially with sequence, and peptides containing Cys, Met, Trp or N-terminal Gln are more prone to oxidation, deamidation or cyclisation than the table's general case suggests.
| State | Condition | Working window | Notes |
|---|---|---|---|
| Lyophilised powder | −20 °C or below; −80 °C for archival material | Long term | Keep sealed and desiccated, protected from light and moisture. The dry solid is the most stable form — leave material lyophilised until it is actually needed. |
| Reconstituted solution | 2–8 °C, refrigerated, protected from light | Short working window | Hydrolysis, oxidation and adsorption to container surfaces all begin once the peptide is in solution. Bacteriostatic water limits microbial growth but does not stop chemical degradation. |
| Frozen aliquots | −20 °C to −80 °C in single-use volumes | Extended, if undisturbed | Aliquot immediately after reconstitution so that each experiment thaws a fresh tube. Low-binding tubes reduce loss for dilute or hydrophobic sequences. |
| Freeze–thaw | Minimise cycles | — | Each cycle concentrates solutes at the ice interface and drives aggregation and loss of activity. Aliquoting is the direct way to avoid repeat cycles; never refreeze a tube that has been through several. |
| Before opening | Let the vial reach room temperature first | — | Opening a cold vial draws in humid air that condenses on the powder. Introduced moisture accelerates hydrolysis and skews any subsequent gravimetric measurement. |
Primary sources, not aggregators. Each of these is a public, authoritative database maintained by a research institution or established curator — use them to verify compound identity and to read the underlying literature directly.
NIH open chemistry database. Confirm compound identity, CID, molecular formula, exact molecular weight, canonical SMILES and InChIKey before you record a compound in a notebook.
NLM index of biomedical literature. The primary place to check what has actually been published on a sequence, and to separate peer-reviewed findings from secondary summaries.
Registry of interventional and observational studies. Shows which compounds have entered registered human trials, at what phase, with what endpoints, and whether results were posted.
Curated protein sequence and function knowledgebase. Use it to resolve the parent protein of a peptide fragment, verify residue numbering, and pull cross-references to other databases.
Experimentally determined and computed 3D structures. Useful for inspecting receptor–ligand binding modes and for structural context behind a mechanism described in a paper.
Computes physicochemical properties directly from a sequence: theoretical molecular weight, pI, extinction coefficient, instability index and GRAVY. The fastest way to sanity-check a molecular weight before a molarity calculation.
Drug, target and pathway knowledgebase. Helpful for identifying the molecular targets and mechanism of action associated with a compound and for locating the supporting citations.
The cited literature index: published trial populations, the regimens those studies used, reported adverse effects and documented interactions.
Reference profiles with mechanisms, study findings, molecular data and citations for each peptide.
Longer-form write-ups of the published literature, with sources linked throughout.
Third-party HPLC and mass-spectrometry documentation — the source of the net content and purity figures used above.
Available research compounds, sizes and pricing, with molecular data on every product page.