Shelf Life for First Order Calculator

Formula Used:

\[ T_{10\%} = \frac{0.105}{A_o} \]

T_10% Concentration: time units

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is Shelf Life for First Order Calculator?

Definition: This calculator estimates the time (T_10%) at which a drug's concentration reaches 10% of its initial value following first-order degradation kinetics.

Purpose: It helps pharmaceutical professionals determine the shelf life of drugs and stability of formulations.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ T_{10\%} = \frac{0.105}{A_o} \]

Where:

\( T_{10\%} \) — Time to reach 10% of initial concentration
\( A_o \) — Initial drug concentration (kg/m³)
0.105 — Constant derived from first-order kinetics (ln(0.1)/-k)

Explanation: The formula calculates the time required for a drug to degrade to 10% of its original concentration based on first-order kinetics.

3. Importance of T_10% Calculation

Details: T_10% is crucial for determining drug stability, shelf life, and storage conditions in pharmaceutical development.

4. Using the Calculator

Tips: Enter the initial drug concentration in kg/m³. The value must be > 0. The calculator will output the time to reach 10% concentration.

5. Frequently Asked Questions (FAQ)

Q1: What does T_10% represent?
A: It's the time when the drug concentration reaches 10% of its initial value, often used to estimate shelf life.

Q2: Why is 10% concentration significant?
A: Many drugs are considered ineffective or unsafe below 10% of their labeled concentration.

Q3: What units does T_10% use?
A: The time units depend on the rate constant used in the derivation (typically days or years).

Q4: How do I find the initial concentration?
A: This is typically measured experimentally at the start of stability testing.

Q5: Does this work for all drugs?
A: Only for drugs that follow first-order degradation kinetics.