In this expert interview, Dr. Nimesh Khadka shares insights into how Raman spectroscopy is revolutionizing bioprocess monitoring. As a process analytical technology (PAT) tool, Raman offers unmatched specificity and real-time data, setting it apart from traditional methods like UV-Vis spectroscopy.
What is Raman Spectroscopy and How Does It Work?
Raman spectroscopy studies how light interacts with vibrating molecules. Most of the light is scattered unchanged (Rayleigh scattering), but a small portion shifts in energy due to molecular vibrations — known as Raman scattering. Though faint, this scattered light carries unique molecular fingerprints that allow precise identification and quantification of compounds.
Why is Raman Ideal for Bioprocess Monitoring?
Raman spectroscopy is particularly suited for real-time, non-invasive monitoring due to:
READ MORE: Gut Microbiome Pattern Found to Predict Future Heart Attack Risk in Heart Disease Patients
- Molecular specificity for identifying substances
- Compatibility with aqueous solutions, as water produces a weak Raman signal
- Non-destructive analysis, preserving sample integrity
- Simultaneous detection of multiple metabolites
- Ability to detect protein structural features (e.g., amide I, II, III, aromatic residues, disulfide bonds)
This makes Raman spectroscopy valuable for capturing dynamic process changes, ensuring product consistency, and minimizing time and cost.
Comparison with UV-Vis Spectroscopy
UV-Vis limitations:
- Susceptible to interference (e.g., from tryptophan)
- Less accurate in complex mixtures
Raman advantages:
- Unaffected by interfering compounds
- Can quantify proteins and excipients (e.g., sucrose, histidine) simultaneously
- Provides accurate, multi-parameter data in one scan
Example Case Study:
In an ultrafiltration/diafiltration (UF/DF) process for monoclonal antibody production:
- UV-Vis overestimated protein concentrations by over 70%
- Raman accuracy was within 5–10%, unaffected by tryptophan interference
Modes of Integration in Bioprocesses
Raman spectroscopy can be deployed:
- In-line – probes inserted directly into the process stream for continuous monitoring
- At-line – samples taken and analyzed nearby
- On-line – samples routed to an external analyzer
In-line Raman is preferred for automated control and uninterrupted data acquisition.
To address data quality challenges (e.g., baseline shifts, overlapping spectra), techniques such as:
- Savitzky-Golay filtering
- Water band normalization
- Partial Least Squares (PLS) regression
are applied to improve prediction accuracy and model robustness.
Advanced Applications in Quality Control
Beyond basic monitoring, Raman supports:
- Real-time protein structure analysis
- Aggregation profiling
- Excipient isolation
- Beta-sheet content quantification
These applications allow deeper insights into process stability and product quality, critical for biopharmaceutical development and manufacturing.
The Strategic Value of Raman in Bioprocessing
Dr. Khadka emphasizes that process Raman spectroscopy delivers unmatched benefits:
- Real-time and specific
- Applicable in upstream and downstream stages
- Non-destructive and scalable
- Improves process understanding, efficiency, and consistency
About Dr. Nimesh Khadka
Dr. Khadka holds a PhD in Biochemistry with a specialization in bioanalytical techniques. At Thermo Fisher Scientific, he serves as a Senior Product Application Specialist, driving the adoption of Raman spectroscopy in PAT applications. His work bridges scientific innovation with real-world bioprocessing solutions.
“Raman spectroscopy is an essential PAT tool that empowers real-time control, enhances product quality, and accelerates decision-making across the biopharmaceutical industry.”
– Dr. Nimesh Khadka
Sponsored Content Disclaimer:
This article was sponsored by Thermo Fisher Scientific. News-Medical.net maintains editorial integrity by only publishing commercial content that aligns with its mission to inform and educate readers in science and healthcare.
