Practice question

Detergents classify based on head group charge: ionic anionic like sodium dodecyl sulfate SDS and sodium deoxycholate, cationic like hexadecyltrimethylammonium bromide and quaternary ammonium compounds, and non-ionic bearing uncharged polar head like polyoxyethylene ethers. Triton X-100 octyl phenol ethoxylate contains hydrophilic polyethylene oxide chain and hydrophobic tert-octylphenyl group without ionizable group, thus non-ionic and relatively mild preserving native protein interactions. SDS possesses negatively charged sulfate, strongly denatures proteins by binding hydrophobic regions and imparting uniform negative charge; sodium deoxycholate is bile salt anionic with carboxylate, harsher than zwitterionic CHAPS. Quaternary ammonium compounds like benzalkonium chloride are cationic disinfectants. Non-ionic detergents are favored for solubilizing membrane proteins while retaining activity because they do not disrupt electrostatic interactions and cause limited unfolding, though they can still delipidate. Triton X-100 critical micelle concentration around 0.2 mM reflects balance of hydrophobic tail and ethoxylate head group size determining micelle formation. Such detailed mechanistic insight is frequently examined in competitive tests including NEET, CUET, CSIR-NET and GATE where transporter classification, energetics and disease linkage are integrated into problem-solving questions.