Arginine Hydrochloride

Size exclusion chromatography (SEC) is widely used to characterize molecular size variants of antibody drugs. However, SEC analysis is hindered by secondary interactions (or nonspecific interactions) between proteins and stationary phase packing, which result in poor column efficiency. Previous studies have reported that chaotropic salt can inhibit these interactions, but the corresponding applications of this aspect are relatively rare. Therefore, this study introduces a novel approach using sodium iodide (NaI) as a mobile-phase component in SEC and investigates the influence of the mobile-phase composition on secondary interactions.

SEC analysis was performed on one antibody-drug conjugate and four monoclonal antibodies (mAbs) using three different mobile-phase systems (i.e., sodium chloride/L-arginine hydrochloride/NaI mobile phases system) to compare the column efficiency. Subsequently, mAb-1 was used as a model to investigate the effects of these factors on secondary interactions by adjusting the ionic strength (salt concentration) and pH of the NaI mobile-phase system.

NaI exhibits superior column efficiency performance in the SEC analysis of most products. The ionic strength will affect nonideal electrostatic and hydrophobic interaction. An appropriate ionic strength can inhibit electrostatic interactions, while an excessive ionic strength increases hydrophobic interactions. pH primarily influences electrostatic interactions. Determining the appropriate pH necessitates consideration of the isoelectric point of the protein and the pH tolerance of the column.

In SEC analysis, using NaI as the salt component in the mobile phase reduces secondary interactions and improves column efficiency. This approach is advantageous for samples with intense secondary interactions and is a suitable alternative.

Aim: To determine the effect of the developed complex treatment of patients with peritonitis on the dynamics of humoral factors of nonspecific reactivity in the course of the disease. Materials and Methods: The study included 124 patients with toxic and terminal stages of peritonitis, who were divided into 3 groups. Group I (main) included 39 patients whose complex treatment included cytochrome C. Group II (main) included 41 patients whose complex treatment included cytochrome C and a solution containing levocarnitine and arginine hydrochloride. The comparison group comprised 44 patients who did not receive the specified drugs. The patients underwent determination of the levels of fibronectin, ceruloplasmin, and procalcitonin in the serum during the course of the disease. Results: In patients of the I and II main groups, the use of the proposed treatment contributed to the optimization of the production of acute phase proteins: a decrease in procalcitonin production during the study, optimization of ceruloplasmin and fibronectin production, especially in the II main group. In patients of the comparison group, decompensation in the production of humoral inflammatory factors was determined, associated with a significant increase in fibronectin production, a decrease in ceruloplasmin content, and an increase in procalcitonin throughout the entire period. Conclusions: The use of cytochrome C and a solution containing levocarnitine and arginine hydrochloride in the complex treatment of patients with disseminated peritonitis helps to optimize the production of acute phase proteins, which leads to a decrease in inflammation and the preservation of factors of nonspecific humoral activity at a subcompensated level.