---
name: ccs-prediction-model-application
description: Use when you have structural input data (SMILES or molecular geometry files) for N-Me derived unsaturated sterol lipids and need to generate a predicted CCS dataset indexed by lipid identifier and structural isomer class.
license: CC-BY-4.0
metadata:
  edam_operation: http://edamontology.org/operation_3927
  edam_topics:
  - http://edamontology.org/topic_3375
  - http://edamontology.org/topic_0602
  - http://edamontology.org/topic_3071
  tools:
  - Python
  - Jupyter Notebook
  - scikit-learn
  - RDKit
  techniques:
  - LC-MS
  - ion-mobility-MS
derived_from:
- doi: 10.1002/anie.202507483
  title: NA
evidence_spans:
- collection of Python scripts
- All functions are implemented in jupyter notebook
claims: []
provenance:
  collection: https://w3id.org/holobiomicslab/asb-skill/collection/metabolomics/v2
  assembled_by: scripts/collect_metabolomics_collection.py
  sources:
  - build: coll_na_cq
    doi: 10.1002/anie.202507483
    title: NA
  dedup_kept_from: coll_na_cq
schema_version: 0.2.0
attribution:
  generator: AgenticScienceBuilder
  original_doi: 10.1002/anie.202507483
  all_source_dois:
  - 10.1002/anie.202507483
  zenodo_doi: 10.5281/zenodo.20794027
  curators: []
  promoter: Louis-Félix Nothias
  sponsor: CNRS & Université Côte d'Azur
---

# CCS Prediction Model Application

## Summary

Apply a machine-learning CCS prediction model trained on quantum chemistry features to estimate collision cross section values for N-Me derived unsaturated sterol lipids. This skill bridges quantum structural calculations to experimental ion mobility predictions, enabling large-scale isomer-level CCS dataset generation without exhaustive experimental measurement.

## When to use

You have structural input data (SMILES or molecular geometry files) for N-Me derived unsaturated sterol lipids and need to generate a predicted CCS dataset indexed by lipid identifier and structural isomer class. This is appropriate when experimental CCS benchmarks are unavailable or when you need fast predictions across a large dataset of lipid variants prior to LC-IM-MS/MS analysis.

## When NOT to use

- Input lipids do not contain N-Me derived unsaturated sterol moieties; model was trained specifically on this lipid class and transfer to other structural classes is not validated.
- CCS values are already available from experimental measurement; prediction adds no value.
- Quantum chemistry features have not been pre-computed; this skill assumes conformational and electronic structure data is already prepared as input.

## Inputs

- Structural input data for N-Me derived unsaturated sterol lipids (SMILES strings or molecular geometry files)
- Quantum chemistry-derived 3D conformational and electronic structure data (per lipid variant)
- Pre-trained SVR model with LASSO-selected features and tuned hyperparameters
- Optional: experimental CCS reference standards or benchmarks for validation

## Outputs

- Predicted CCS values tabular dataset (indexed by lipid identifier and structural isomer class)
- CCS prediction model performance metrics (e.g., cross-validation scores, prediction accuracy vs. benchmarks)
- Model feature importance or coefficients (from LASSO selection)

## How to apply

First, prepare 3D conformational and electronic structure data for each lipid variant using quantum chemistry calculations on the structural input. Extract quantum chemistry features from the conformational ensemble and feed them to a scikit-learn SVR (Support Vector Regressor) model pre-trained with LASSO feature selection and hyperparameter tuning via cross-validation. Generate CCS predictions for the full lipid dataset and compile predicted values into a tabular dataset indexed by lipid identifier and structural isomer class. Validate predicted CCS against reference standards or experimental benchmarks where available to assess prediction accuracy before downstream use in 4D sterolomics data processing.

## Related tools

- **scikit-learn** (Machine learning framework for training SVR model with LASSO feature selection and cross-validation hyperparameter tuning)
- **RDKit** (Molecular structure parsing and feature extraction from SMILES and molecular geometry inputs)
- **Python** (Primary programming language for model implementation and CCS prediction workflow execution)
- **Jupyter Notebook** (Interactive notebook environment for implementing and executing the CCS prediction workflow)

## Evaluation signals

- Predicted CCS values fall within the expected physical range for the lipid class (e.g., monotonic increase with molecular size or expected isomeric differences).
- Cross-validation error metrics (e.g., mean absolute error, R² score) on held-out folds are within acceptable bounds (as reported in the paper or validated against reference standards).
- Predicted CCS dataset is non-empty, fully indexed by lipid identifier and structural isomer class, with no missing or NaN values for valid input structures.
- Validation against experimental benchmarks (where available) shows prediction accuracy compatible with downstream LC-IM-MS/MS based 4D sterolomics data processing.
- Feature importance ranking from LASSO selection is consistent with expected quantum chemistry predictors of collisional cross section (e.g., molecular size, shape, dipole moment).

## Limitations

- Model is trained and validated specifically for N-Me derived unsaturated sterol lipids; applicability to other lipid classes or structural variants is not established.
- Quantum chemistry feature extraction is computationally expensive; scaling to very large datasets (>10,000 variants) may require optimization or parallelization.
- Prediction accuracy depends on the quality and diversity of the training set; lipid variants far outside the training chemical space may have inflated uncertainty.
- SVR hyperparameter tuning via cross-validation requires careful selection of the regularization parameter (C) and kernel parameters; poor tuning can lead to overfitting or systematic bias.

## Evidence

- [intro] Apply machine-learning CCS prediction model trained on quantum chemistry features to estimate CCS values for the full lipid dataset.: "Apply machine-learning CCS prediction model trained on quantum chemistry features to estimate CCS values for the full lipid dataset."
- [readme] The CCS prediction process in the paper is implemented using the scikit-learn API. It employs LASSO for feature selection and uses cross-validation to select the best hyperparameters for the SVR model.: "The CCS prediction process in the paper is implemented using the scikit-learn API. It employs LASSO for feature selection and uses cross-validation to select the best hyperparameters for the SVR"
- [intro] Compile predicted CCS values into a tabular dataset indexed by lipid identifier and structural isomer class.: "Compile predicted CCS values into a tabular dataset indexed by lipid identifier and structural isomer class."
- [intro] Validate predicted CCS against reference standards or experimental benchmarks where available.: "Validate predicted CCS against reference standards or experimental benchmarks where available."
- [readme] QCC-Assited dataset CCS prediction workflow of N-Me derived unsaturated sterol lipids: "QCC-Assited dataset CCS prediction workflow of N-Me derived unsaturated sterol lipids"