Palavras-chave: razão de modulação, cromatografia gasosa bidimensional abrangente, espectrometria de massas quadrupolar, quantificação.Resumo:  Esse artigo apresenta uma discussão sobre as implicações da razão de modulação (MR ) na cromatografia gasosa bidimensional abrangente (GC×GC). Os conceitos foram discutidos em formato tutorial, que é essencialmente uma revisão da literatura. A MR é definida como a razão entre a largura do pico eluído da coluna da primeira dimensão (1 D) e o período de modulação usado na operação do GC×GC em número adimensional. Como demonstrado aqui, existem muito parâmetros de GC×GC que são dependentes ou podem ser interpretados por considerações relativas ao valor da MR . Dentre eles, destacam-se o aumento da amplitude do pico, o número de modulações por pico observada, a detectabilidade de cada um desses picos, o efeito do formato do pico sobre a distribuição dos picos modulados e como o tempo de retenção dos picos monodimensionais pode ser derivada dessa distribuição. Também serão discutidas considerações sobre como as dimensões físicas e a fase de recobrimento da segunda coluna (2 D) usada em GC×GC (isso controla o tempo de retenção total dos picos na coluna 2 D) podem ser interpretadas com base na MR, , e como esse parâmetro pode auxiliar na interpretação da separação de isômeros.

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