## 3 Results and Discussion
### Adsorption Kinetics  
#### 3.4.1 Adsorption Isotherms  
Adsorption isotherms may be used to describe how much material is adsorbed as a function of initial concentration at constant temperature, which in this case was ambient temperature. The linear versions of the Langmuir and Freundlich isotherms were used to assess the adsorption data (Table 3). Based on the observed R\({}^{2}\), the Freundlich isotherm appears to be the best descriptor of the adsorption isotherm. The Freundlich isotherm, characterized by its non-linear nature, suggests a heterogeneity in the binding sites' adsorption capacity of the polymer. The preference for the Freundlich isotherm over the Langmuir indicates that the adsorption process for both MIP and NIP surfaces is not limited to a single monolayer. Instead, it suggests the formation of multilayers of adsorbate molecules on the polymer surface. Moreover, the affinity of both these polymer materials implies potential application, including but not limited to separation purification processes. The values of 1/n for each drug provide insights into the surface characteristics, adsorption intensity, and non-linearity in the adsorption process. These values help us understand the adsorption behavior of each drug and its interaction with the adsorbent surface. Two groups of drug compounds can be discerned based on similarities in their 1/n values. Emtricitabine (1.1968) and ibuprofen (16.359) both exhibit heterogeneous surfaces, suggesting diverse adsorption sites. However, emtricitabine demonstrates a moderate adsorption intensity, implying a balanced adsorption process across different concentrations. Conversely, the drug ibuprofen displays a low adsorption intensity, indicating less favorable adsorption conditions. Moreover, while emtricitabine shows moderate non-linearity in adsorption, ibuprofen demonstrates high non-linearity, indicating a steep increase in adsorption capacity with decreasing concentration.  
Similarly, tenofovir (0.302) and diclofenac (0.7003) present highly heterogeneous surfaces conducive to strong adsorption at low concentrations. Despite this similarity, both drugs exhibit a moderate adsorption intensity, suggesting favorable adsorption conditions. Moreover, their non-linearity in adsorption is high, with a steep rise in adsorption capacity observed as concentration decreases.  
Individually, naproxen (2.487) showcases considerable surface heterogeneity, potentially with varying adsorption sites. Its relatively high adsorption intensity suggests weaker adsorption at low concentrations, while moderate non-linearity in adsorption implies a moderate increase in adsorption capacity with decreasing concentration. In contrast, efavirenz (1.5028) demonstrates a relatively homogeneous surface with consistent adsorption sites. The moderate adsorption intensity observed suggests a balanced adsorption process, while moderate non-linearity in adsorption indicates a gradual increase in adsorption capacity with decreasing concentration. The \(K_{f}\) values indicate the adsorption behavior of the adsorbent material. For \(K_{f}\) = 0.6943 and \(K_{f}\) = 0.8050, moderate adsorption capacities are observed, suitable for efficient adsorption processes in wastewater treatment or purification applications. Conversely, for \(K_{f}\) = 5.3002 and \(K_{f}\) = 4.3672, significantly higher adsorption capacities are evident, which is ideal for the thorough removal of solutes or pollutants from solutions, such as in environmental remediation or industrial processes. Lastly, for \(K_{f}\) = 0.0389 and \(K_{f}\) = 0.0535, low adsorption capacities are observed, which may find utility in applications requiring selective adsorption or trace contaminant removal.