## 1 Introduction  
Corticosteroids are known to be extremely efficient drugs and are broadly employed for the treatment of inflammatory skin diseases like eczema, dermatoses, and psoriasis [1, 2, 3] to tentatively alleviate their symptoms [4, 5].  
Dexamethasone and hydrocortisone, as types of corticosteroids, are mostly used in the form of ointments, gels, and creams, with varying potentiality and efficiency for topical use [6, 7]. For this reason, certain producers illegally put dexamethasone and hydrocortisone in cosmetics to enhance the effects of their commercially accessible products. The application of cosmetics provides many benefits, including preventing human skin from aging, increasing elasticity, and eliminating wrinkles. In a majority of cases, cosmetics are utilized daily by teenagers, men, and women, and this prolongs the exposure of skin to cosmetics. Prolonged use of cosmetics contaminated by dexamethasone or hydrocortisone can cause many grave adverse effects to arise, such as cutaneous reactivity, skin atrophy, some systematic side effects, diabetes mellitus, and hypertension [7, 8].  
According to EU Cosmetics Regulations, corticosteroids like dexamethasone and hydrocortisone have been prohibited in the creation of cosmetic products [9]. Thus, there is an obligation to research and produce efficient and rapid technology for screening dexamethasone or hydrocortisone in cosmetics. Currently, there are many conventional methods for detecting these hormones in cosmetics, such as ionic liquid micro extraction [10], solid phase extraction (SPE) [11; 12], and liquid phase extraction [13; 14; 15]. Unfortunately, these technologies are often time-consuming, difficult to use, and need great quantities of reagents and solvents. Thus, choosing a suitable sample preparation technique is key for the effective examination of complex samples.  
MIPs are made using molecular imprinting methods and are designed to selectively acknowledge target molecules [16]. MIPs are simple to make and provide better selectivity for substrates compared with conventional separation technologies. However, when MIPs are utilized for the extraction of absorbed target molecules, there is frequently a loss of certain substances. In order to minimize this disadvantage, magnetic molecular imprinted polymers (MMIPs) are seeing a gradual increase in utilization in separation applications and substance treatment [17; 18]. MMIPs are defined by more precise selectivity for guest molecules and unique magnetic response characteristics [19; 20]. [PERSON] et al. tested the ability MMIPs and MNIPs to separate dexamethasone and hydrocortisone from cosmetic products [21]; adsorption proved to be successful for the extraction of the target molecules (hydrocortisone and dexamethasone) from the cosmetics samples due to their great extraction efficiency, versatility, and simple operation (in terms of the characteristics of the adsorbents). Hydrocortisone and dexamethasone adsorption isotherms were used to analyze and understand the adsorption process and to describe the behavior of the adsorption amount and adsorbent affinity. A statistical physics treatment based on analytical models was adopted to theoretically describe the adsorption isotherms, and this reflected a saturated adsorption process at elevated concentrations.  
The aim of this article is to comprehend the adsorption phenomena of hydrocortisone and dexamethasone on magnetic molecularly imprinted polymer (MMIP) and magnetic non-molecularly imprinted polymer (MNIP) adsorbents through the application of statistical physics formalism, and to carry out a corresponding investigation of the physicochemical parameters that present a clear physical correlation with the adsorption phenomena. This work gives advanced theoretical results on the adsorption of cosmetic products using molecularly imprinted polymers.