Recently, the deep learning (DL) dimension of artificial
intelligence
has received much attention from biochemical researchers and thus
has gradually become the key approach adopted in the area of biosensing
applications. Studies have shown that the use of DL techniques for
sensing can not only shorten the time of data analysis but also significantly
increase the accuracy of data analysis and prediction, resulting in
the performance improvement of biosensing systems in comparison to
conventional methods. However, obtaining reliable equilibrium and
rate constants of biomolecular interactions during the detection process
remains difficult and time-consuming to date. In this study, we propose
a transformed model based on the deep transfer learning and sequence-to-sequence
autoencoder that can successfully transfer the SPR sensorgram to the
protein-binding constants, that is, the association rate constant
(k
a) and dissociation rate constant (k
d), which provide crucial information to understand
the mechanisms of drug action and the functional structures of biomolecules.
Experimentally, we first trained and tested the pre-trained model
using the Langmuir model which generated ideal SPR sensorgrams and
then we fine-tuned the pre-trained model through the augmented SPR
sensorgrams which were synthesized by using the synthesized minority
oversampling technique (SMOTE) through the moderate-scale experiment.
Next, the fine-tuned model was inputted with a short experimental
SPR sensorgram that only needs 110 s, and the sensorgram was directly
transformed into a reconstructed ideal sensorgram. Finally, the binding
kinetic constants, that is, k
a and k
d, as outputs, were obtained through fitting
the reconstructed ideal sensorgram. The results showed that the prediction
errors of k
a and k
d obtained by our model were less than 12 and 24%, respectively.
Based on the convenience, accuracy, and reliability of the proposed
DL approach, we believe our strategy significantly boosts the feasibility
to monitor the binding affinity of antibodies online during production.