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Glycan and Lectin Assays on the P4SPR
Put the sugar on the sensor to catch what binds it, or put sugar-binding proteins on the sensor to read the sugars. Both work label-free on the P4SPR.
The need
Glycans cover cells, viruses and bacteria, and they change with disease. They are hard to measure: there is no way to amplify them, their binding partners are often weak and promiscuous, and adding a label can change the very structure being studied. Label-free binding in real time needs no amplification and no label, and shows each interaction as it happens.
Two ways to set up the sensor
Glycan on the sensor. A synthetic glycan is attached to the surface, and the sample flows over it. Anything that binds the glycan, such as antibodies in serum or a lectin, gives a signal. Lectin on the sensor. Lectins, proteins that recognize particular sugars, are attached instead, and the glycan-carrying molecule is the sample. Because each lectin recognizes several sugars, a panel of lectins gives a pattern rather than a single yes or no (Figure 1).
What the studies showed
| Result | |
|---|---|
| Tumour glycan (Tn antigen) on the sensor | Anti-Tn antibodies detected down to 0.3 nM in diluted human serum; serum from prostate cancer patients told apart from cancer-free donors (proof of concept) |
| Reuse | The glycan sensor was regenerated and reused at least 60 times with no significant loss in sensitivity |
| Lectin panel on AffiCoat | LPS from E. coli (two serotypes), K. pneumoniae, P. aeruginosa and S. enterica classified from their lectin patterns |
| How many lectins | Four lectins identified the LPS about as well as all seven (Figure 2) |
Full methods and data: Lamarre et al., Analyst 2021, and Lamarre and Boudreau, ACS Omega 2025 (references below).
Why the P4SPR fits glycan work
| What glycan assays need | What the P4SPR brings |
|---|---|
| No labels on the sugars | Label-free binding, in real time |
| A pattern, not one number | Four channels, read in turn: one lectin per channel, or sample and reference |
| Low background in serum | AffiCoat low-fouling surface |
| Many samples on one surface | Glycan and lectin surfaces can be regenerated and reused |
| A setup any lab can run | Benchtop and portable; syringe injection |
Beyond these two studies
The same two setups cover most glycan questions: glycosylation of a therapeutic protein from batch to batch, antibodies against glycan antigens in vaccine or cancer research, lectin specificity, and glycan-binding pathogens and toxins.
What you need
| Item | Source |
|---|---|
| P4SPR | Affinité Instruments |
| Glycan Sensor (SAMGLY-01) for biotinylated glycans, or AffiCoat Sensor (SAMAC-01) with the Amine Coupling Kit (AMIN-KIT) for lectins and glycoproteins | Affinité Instruments |
| Glycan Analysis Kit (GLY-KIT): blocking solution, lectin-compatible running buffer, regeneration scouting | Affinité Instruments |
| Glycans or lectins (here: synthetic Tn antigen; seven plant lectins) | Commercial or synthesized |
References
- M. Lamarre, T. Tremblay, M.-A. Bansept, K. Robitaille, V. Fradet, D. Giguère, D. Boudreau, "A glycan-based plasmonic sensor for prostate cancer diagnosis," Analyst, 2021. doi:10.1039/d1an00789k.
- M. Lamarre, D. Boudreau, "Lipopolysaccharide detection with glycan-specific lectins — a nonspecific binding approach applied to surface plasmon resonance," ACS Omega, 2025. doi:10.1021/acsomega.5c00867 (open access).
Illustrations by Affinité Instruments. Figure 2 shows the accuracies reported in reference 2.