An epitope-imprinted piezoelectric diagnostic tool for Neisseria meningitidis detection

Neisseria meningitidis, a human-specific bacterial pathogen causes bacterial meningitis by invading the meninges (outer lining) of central nervous system. It is the polysaccharide present on the bacterial capsid that distinguishes various serogroups of N. meningitidis and can be utilized as antigens to elicit immune response. A computational approach identified candidate T-cell epitopes from outer membrane proteins Por B of N. meningitidis (MC58): (²⁷³ KGLVDDADI²⁸² in loop VII and ¹⁷⁰ GRHNSESYH¹⁷⁹ in loop IV) present on the exposed surface of immunogenic loops of class 3 outer membrane proteins allele of N. meningitidis. One of them, KGLVDDADI is used here for designing a diagnostic tool via molecularly imprinted piezoelectric sensor (molecularly imprinted polymer-quartz crystal microbalance) for N. meningitidis strain MC58. Methacrylic acid, ethylene glycol dimethacrylate and azoisobutyronitrile were used as functional monomer, cross-linker and initiator, respectively. The epitope can be simultaneously bound to methacrylic acid and fitted into the shape-selective cavities. On extraction of epitope sequence from thus grafted polymeric film, shape-selective and sensitive sites were generated on electrochemical quartz crystal microbalance crystal, ie, known as epitope imprinted polymers. Imprinting was characterized by atomic force microscopy images. The epitope-imprinted sensor was able to selectively bind N. meningitidis proteins present in blood serum of patients suffering from brain fever. Thus, fabricated sensor can be used as a diagnostic tool for meningitis disease.