PulseGrowth

Growth kinetics and metabolic rate estimation for mammalian cell culture

→ Open the live app

---

What is PulseGrowth?

PulseGrowth is a browser-based kinetics calculator for mammalian cell culture. It converts routine two-point sampling data into the growth and metabolic metrics needed for passaging decisions, clone comparisons, and feeding corrections.

The app is organized into three modules: growth kinetics (μ, doubling time, IVCD), specific metabolite consumption rates (qGlc, qGln), and a simple feed correction estimator. All three are designed for quick bench-side use during culture operations.

No installation. No server. Runs entirely in the browser.

---

Why it matters

Routine culture monitoring generates two data points at every sampling: a cell count and a set of metabolite concentrations. Extracting actionable metrics from those points — growth rate, doubling time, specific consumption rates — requires several non-trivial calculations that are error-prone to do by hand. Without a dedicated tool:

• μ and doubling time must be derived manually from a logarithmic expression
• Specific rates require IVCD normalization, which is rarely computed at the bench
• Unit conversions (g/L → mM) are applied inconsistently, making q values incomparable across runs
• Feed correction volumes must be calculated separately from a different formula

PulseGrowth covers all three steps in one interface, with consistent unit handling throughout.

---

How it works

Module 1 — Bio-Kinetics

Enter X₀, X₁, and Δt (in hours or days). PulseGrowth returns:

• Specific growth rate (μ)
• Doubling time (t_d)
• Expansion factor (X₁ / X₀)
• IVCD (exponential approximation, for downstream q calculations)

Module 2 — Metabolics (q)

Enter glucose and/or glutamine concentrations as C₀ → C₁, selecting g/L or mM. The app converts g/L to mM internally using fixed molecular weights (Glc = 180.156 g/mol, Gln = 146.145 g/mol), then normalizes the concentration change by IVCD:

• qGlc — specific glucose consumption (pmol/cell/day)
• qGln — specific glutamine consumption (pmol/cell/day)

A positive q means net consumption (C₀ > C₁). Entering values in g/L or mM produces equivalent results because units are normalized before computing.

Module 3 — Feed Control

Enter culture volume, stock concentration, current concentration, and target concentration. PulseGrowth returns the feed volume required to restore the target level in a single addition. Intended as a quick operational estimate, not a full dynamic feeding model.

---

Methods

Exponential growth model

$$\mu = \frac{\ln(X_1 / X_0)}{\Delta t} \qquad t_d = \frac{\ln 2}{\mu} \qquad \text{Expansion} = \frac{X_1}{X_0}$$

IVCD (exponential approximation between two points)

$$IVCD = \left(\frac{X_1 - X_0}{\ln(X_1/X_0)}\right) \Delta t$$

Specific metabolite consumption rate

$$q = \frac{\Delta C}{IVCD} \times 24$$

where ΔC = C₀ − C₁ in mM, IVCD in 10⁶ cells·h/mL, and the factor 24 converts from per-hour to per-day.

Feed correction (single addition)

$$V_{feed} = \frac{(C_{target} - C_{current}) \times V_{culture}}{C_{stock} - C_{target}}$$

---

Features

Growth kinetics	Computes μ, doubling time, expansion factor, and IVCD from two sampling points
IVCD-normalized q	qGlc and qGln estimated using exponential IVCD for consistent inter-run comparison
Unit-aware metabolite inputs	Accepts g/L or mM; converts internally before computing q
Feed correction estimator	Single-addition feed volume for glucose and glutamine correction
Flexible time input	Manual Δt or start/end datetime
Offline-first PWA	Service Worker caches all assets; works without internet after first load
Bilingual UI	Full Spanish / English interface
No installation	Opens instantly in any modern browser; installable on Android, iOS, and desktop

---

Tech stack

Frontend

Deployment

Fully static — no backend, no framework, no build step.

---

Project structure

PulseGrowth/
├── index.html              ← markup only
├── manifest.json           ← PWA manifest
├── sw.js                   ← Service Worker (cache-first, offline support)
├── icon-192.png
├── icon-512.png
├── icon-maskable-192.png
├── icon-maskable-512.png
└── src/
    ├── css/
    │   └── app.css         ← all styles
    └── js/
        ├── i18n.js         ← translation strings (ES / EN)
        └── app.js          ← all application logic

---

Author

Emiliano Balderas Ramírez Bioengineer · PhD Candidate in Biochemical Sciences Instituto de Biotecnología (IBt), UNAM

---

Related

CellSplit — Neubauer cell counting and passage planning for CHO cultures.

Kinetic Drive — interactive kinetic analysis for mammalian cell culture data.

Clonalyzer 2 — fed-batch kinetics analysis with clone comparisons and publication-ready plots.

CellBlock — shared biosafety cabinet scheduling for cell culture research groups.

---

PulseGrowth — two sampling points, full kinetic picture.