Peptides are short chains of amino acids that play crucial roles in various biological processes. In research and therapeutic applications, accurate dosage is paramount. This calculator helps determine the correct amount of peptide to administer based on purity, concentration, and desired dosage.
How it Works:
The calculation involves several steps to ensure accuracy:
Calculate Actual Peptide Content: Since lyophilized peptides often contain excipients (like mannitol) and have a stated purity, the actual amount of active peptide is less than the total weight. This is calculated by multiplying the peptide weight by its purity.
Formula: Actual Peptide (mg) = Peptide Weight (mg) * (Peptide Purity / 100)
Determine Total Daily Peptide Required: Based on the desired dosage per kilogram of body weight and the individual's weight, the total daily amount of active peptide needed is calculated.
Formula: Total Daily Peptide (mg) = Desired Dose (mg/kg/day) * Body Weight (kg)
Calculate Concentration in Reconstituted Vial: After reconstituting the peptide powder with a specific volume of diluent (e.g., bacteriostatic water), the concentration of the active peptide in the solution is determined.
Formula: Concentration (mg/ml) = Actual Peptide (mg) / Reconstitution Volume (ml)
Calculate Volume to Inject: Finally, the volume of the reconstituted solution to inject to achieve the desired daily dose is calculated.
Formula: Volume to Inject (ml) = Total Daily Peptide (mg) / Concentration (mg/ml)
Example Calculation:
Let's say you have:
Peptide Purity: 98%
Peptide Weight: 10 mg
Desired Dose: 0.1 mg/kg/day
Body Weight: 70 kg
Reconstitution Volume: 5 ml
Step 1: Actual Peptide Content 10 mg * (98 / 100) = 9.8 mg actual peptide
Step 2: Total Daily Peptide Required 0.1 mg/kg/day * 70 kg = 7 mg/day
Step 3: Concentration in Reconstituted Vial 9.8 mg / 5 ml = 1.96 mg/ml
Step 4: Volume to Inject 7 mg / 1.96 mg/ml = 3.57 ml
In this example, you would need to inject approximately 3.57 ml of the reconstituted solution daily.
Important Considerations:
Purity: Always use the stated purity of the peptide. Higher purity means more active peptide per milligram.
Reconstitution: Use sterile diluents like bacteriostatic water or sterile water. The choice of volume affects concentration.
Units: Ensure all units are consistent (mg, kg, ml).
Disclaimer: This calculator is for informational and educational purposes only. It is not a substitute for professional medical advice. Always consult with a qualified healthcare provider or a peptide specialist for personalized dosage recommendations.
function calculatePeptideDosage() {
var peptidePurity = parseFloat(document.getElementById("peptidePurity").value);
var peptideWeightMg = parseFloat(document.getElementById("peptideWeightMg").value);
var desiredDoseMg = parseFloat(document.getElementById("desiredDoseMg").value);
var bodyWeightKg = parseFloat(document.getElementById("bodyWeightKg").value);
var reconstitutionVolumeMl = parseFloat(document.getElementById("reconstitutionVolumeMl").value);
var resultDiv = document.getElementById("result");
resultDiv.innerHTML = "; // Clear previous result
if (isNaN(peptidePurity) || isNaN(peptideWeightMg) || isNaN(desiredDoseMg) || isNaN(bodyWeightKg) || isNaN(reconstitutionVolumeMl)) {
resultDiv.innerHTML = "Please enter valid numbers for all fields.";
return;
}
if (peptidePurity <= 0 || peptideWeightMg <= 0 || desiredDoseMg <= 0 || bodyWeightKg <= 0 || reconstitutionVolumeMl 100) {
resultDiv.innerHTML = "Peptide purity cannot exceed 100%.";
return;
}
// Step 1: Calculate Actual Peptide Content
var actualPeptideContentMg = peptideWeightMg * (peptidePurity / 100);
// Step 2: Determine Total Daily Peptide Required
var totalDailyPeptideRequiredMg = desiredDoseMg * bodyWeightKg;
// Step 3: Calculate Concentration in Reconstituted Vial
var concentrationMgPerMl = actualPeptideContentMg / reconstitutionVolumeMl;
// Step 4: Calculate Volume to Inject
var volumeToInjectMl = totalDailyPeptideRequiredMg / concentrationMgPerMl;
// Display the result
if (volumeToInjectMl < 0) {
resultDiv.innerHTML = "Calculation resulted in a negative volume. Please check inputs.";
} else {
resultDiv.innerHTML = "Volume to Inject: " + volumeToInjectMl.toFixed(2) + " ml";
}
}