Study on Microwave Power and Temperature Synergistic Control Technology to Improve the Efficiency of Solid-Phase Peptide Synthesis
Study on Microwave Power and Temperature Synergistic Control Technology to Improve the Efficiency of Solid-Phase Peptide Synthesis
Peptides are important raw materials in the fields of biomedicine, cosmetics, and functional foods, and solid-phase synthesis is their mainstream preparation method. Traditional heating methods have problems such as long reaction times, large temperature fluctuations, and low purity of difficult sequences. Commonly used pulsed microwave equipment, due to intermittent heating, struggles to consistently utilize microwaves to promote synthetic reactions. Addressing these issues, a research team at Nanjing University of Technology conducted studies on solid-phase peptide synthesis under microwave power and temperature synergistic regulation, providing a new engineering-feasible method for efficient and stable peptide synthesis.
The research team independently built a continuous microwave heating and cooling circulation system. By using an external transparent fluorinated liquid for circulation cooling, combined with real-time temperature measurement via optical fiber, precise and stable control of microwave power and reaction temperature was achieved. This system can maintain continuous microwave output throughout the entire process, avoiding the temperature fluctuations and low energy utilization caused by intermittent pulsed microwave operation, while also reducing dependence on imported temperature control modules, thus offering advantages in equipment cost and supply chain risk.
In terms of process optimization, the researchers replaced piperidine, which has a carcinogenic risk, with pyrrolidine as a deprotection reagent. Through experiments, they determined the optimal reaction conditions: Fmoc protecting group deprotection was carried out using a two-step method of 2.5 min + 2.5 min, and the peptide chain coupling time was 3.5 min. Compared with traditional processes, the reaction time for key steps was significantly shortened.
To verify the technical effect, the team selected the hydrophobic and difficult-to-synthesize nonapeptide GILTVSVAV as a model sequence and compared three heating methods—continuous microwave, pulsed microwave, and traditional water bath—at the same temperature. The results showed that under continuous microwave conditions, the product purity was the highest, reaching 50.23% and 66.76% at 60 ℃ and 75 ℃, respectively, higher than the pulsed microwave group and 10%–20% higher than the traditional water bath. Within the same short time, the purity with water bath heating dropped significantly, whereas continuous microwave still maintained high purity, indicating the non-thermal effects of microwave can enhance reaction activity and inhibit side reactions.
From the perspective of synthesis efficiency, the traditional method required about 62 minutes to complete one amino acid cycle, with a total synthesis time of 581 minutes; continuous microwave reduced a single cycle to 17.5 minutes, with a total duration of only 162.5 minutes, shortening the time by about 70% and resulting in fewer product impurities.
This study demonstrates that the continuous microwave synthesis technology, with synergistic regulation of microwave power and temperature, can obtain higher-purity peptides in a shorter time, making it particularly suitable for the efficient synthesis of difficult sequences. This technology shows outstanding performance in enhancing reaction rates, reducing side reactions, and improving energy efficiency, while using green reagents, resulting in better safety and environmental friendliness. The relevant results can provide technical references for the industrial synthesis of complex peptides and support the mechanistic research and localization of microwave equipment in the field of peptide synthesis.
Reference：Li F, Yang X, Su XB. Microwave Power-Temperature Synergistic Control in Solid-Phase Peptide Synthesis[J]. Journal of Chemical Engineering of Chinese Universities, 2026, 40(1): 71-81.
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